Petraliellidae Harmer, 1957 (Bryozoa: Cheilostomata) from Queensland, Australia

Abstract

Several species of the family Petraliellidae were first described from the coast of Queensland, including the type species of Sinupetraliella, S.
litoralis. These species are redescribed from type, or topotype specimens, and include Petraliella
concinna, which has not been certainly found since its introduction in 1891; lectotype material is designated for P.
buski and P.
magna. Six other species are described from Queensland, P.
crassocirca, P.
dentilabris, P.
dorsiporosa, Mucropetraliella
bennetti,
M.
serrata and M.
tuberosa. The species Mucropetraliella
tuberosa is a new addition to the Queensland fauna and is described and illustrated here for the first time since its introduction in 1884. The characters of the family Petraliellidae are briefly discussed and the genera to which the Queensland species are assigned is reviewed. A taxonomic key to the ten Queensland petraliellid species described is also provided.

Full text

Systematics and Biodiversity 2(3): 319–339 Issued 31 January 2005
DOI: 10.1017/S1477200004001525 Printed in the United Kingdom C
The Natural History Museum
Kevin J. Tilbrook1,2*&
PatriciaL.Cook
3
1Earth and Oceanic Sciences
Research Institute, Auckland
University of Technology,
Private Bag 92006,
Auckland 1020, NZ
2Scientific Associate,
Department of Zoology, The
Natural History Museum,
Cromwell Road, London,
SW7 5BD, UK
3School of Ecology and
Environment, Deakin University,
Melbourne Campus,
Burwood Highway, Burwood,
Victoria 3125, Australia
submitted November 2003
accepted June 2004
Petraliellidae Harmer, 1957 (Bryozoa:
Cheilostomata) from Queensland,
Australia
Abstract Several species of the family Petraliellidae were first described from the
coast of Queensland, including the type species of Sinupetraliella,S.litoralis.These
species are redescribed from type, or topotype specimens, and include Petraliella
concinna, which has not been certainly found since its introduction in 1891; lectotype
material is designated for P. buski and P. magna. Six other species are described
from Queensland, P. crassocirca,P. dentilabris,P. dorsiporosa,Mucropetraliella
bennetti, M. serrata and M. tuberosa. The species Mucropetraliella tuberosa is a new
addition to the Queensland fauna and is described and illustrated here for the first
time since its introduction in 1884. The characters of the family Petraliellidae are
briefly discussed and the genera to which the Queensland species are assigned is
reviewed. A taxonomic key to the ten Queensland petraliellid species described is
also provided.
Key words Bryozoa, Cheilostomata, taxonomy, Petraliellidae, Petraliella,Mucropet-
raliella,Sinupetraliella, Queensland, Australia, Great Barrier Reef, new record
Introduction
The family Petraliellidae Harmer, 1957 has a pan-tropical to
pan-temperate distribution, but the majority of species occur in
the Indo-West Pacific region. Australasia has a diverse fauna,
the greater part of which was first described from New South
Wales and Victoria. However, some well-known species, to-
gether with some rarely reported forms, were originally de-
scribed from Queensland. The northeastern coast of Australia
has a particularly diverse bryozoan fauna, the Great Barrier
Reef containing over 500 species. Therefore the illustration of
species from this area using their type material will not only
aid biogeographic and ecological studies in the future but also
perhaps bring bryozoans themselves more into the mainstream
of ecological research within coral reef ecosystems.
Although the families Petraliidae Levinsen, 1909 and
Petraliellidae Harmer, 1957 are well defined, generic distinc-
tions are notoriously difficult to maintain. It is important that all
species are revised from examination of type material before
existing genera are redefined, and species assigned to them.
The investigations reported here are confined to species re-
corded from Queensland, which are described and illustrated,
using scanning electron micrographs, often for the first time.
Detailed morphology of the orifices, the frontal shields, the
avicularia and ovicells, together with that of the basal radicu-
lar chambers, is illustrated for each species discussed by direct
reference to type material.
*Corresponding author. Email: Kevin.Tilbrook@aut.ac.nz
The taxonomic history of the family Petraliellidae has
been complicated by the various usages of terms purporting
to describe morphological features used in the assignment of
species to genera. Neither the homology nor function of these
features has been fully investigated; the terms and their usage
here are as follows.
Condyles – paired lateral processes on the inner surface
of the orificial margin, inferred to be attached to, and function
in the articulation of the operculum (e.g. Figs 1C, 4B and
6A). The term is usually, but not invariably, considered to
be a synonym of cardelles, and sometimes of hinge-teeth.
Condyles occur in species of the genus Petraliella but have
not been observed in Sinupetraliella.InMucropetraliella the
operculum articulates about the proximal edge of a ledge of
calcification on the inner edge of the anter (e.g. Figs 10A, 11E)
or occlusor-laminae (Fig. 1E).
Lateral denticles – paired tooth-like processes on the
outer surface of the lateral margin of the orifice, i.e. outside
the operculum (e.g. Figs 9A, 11A). The term is usually, but
not invariably considered to be a synonym of extra-opercular
teeth and sometimes of hinge-teeth. Lateral denticles occur
in species of Petraliella,Mucropetraliella and Sinupetraliella
(e.g. Figs 1E, 3A, 12A).
Median denticle – the equivalent of a lyrula, in most cases
this structure appears on the proximal border of the orifice,
outside the operculum. This character is seen in species of the
genera Petraliella and Mucropetraliella (e.g. Figs 2A, 8A).
Lateral sinuses – these are rounded spaces between the
median and lateral denticles. If additional proximal denticles
319

320 K. J. Tilbrook & P. L. Cook
are present (e.g. Fig. 5B), the outermost pair (usually slightly
larger than the remainder) are the lateral denticles and sinuses.
These are only seen in species of the genera Petraliella and
Mucropetraliella (e.g. Fig. 8A).
Radicular chamber – all petraliellids possess septular
pores in the basal exterior walls, which are usually exposed.
Sometimes these are small and have only one pore, although
there may be many of them (e.g. Petraliella magna:Fig.7E).
In nearly all other species, the basal septular pores are grouped
in multiporous clusters, often with a raised rim of calcified
wall surrounding each cluster (e.g. Figs 2D, 5C). They have
been termed basal pore-chambers, and they resemble many
pore-chambers in structure in that a septular pore leads into a
small coelomic space bounded by exterior cuticle. The radicu-
lar chambers are capable of producing rhizoids (Fig. 10D),
and although these are common, they are not always
developed.
Systematics
Family Petraliellidae Harmer, 1957
Petraliellidae Harmer, 1957: 692.
TYPE GENUS: Petraliella Canu & Bassler, 1927.
Diagnosis
Colonies encrusting, unilaminar to semi-erect or tubular, oc-
casionally lunulitiform. Zooids large, frontal shield uniformly
perforate with distinct marginal areolar pores. Orifices large,
some with lateral indentations and condyles, some with lateral
and proximal denticles, others with lateral denticles and prox-
imal sinus; sometimes thickened suborally to produce a mucro,
which is usually part of the subrostral chamber of an avicu-
larium. Oral spines only present in some species. Ovicells,
closed by the operculum, frontal usually globular, prominent,
finely porous and tuberculate, ectooecium cuticular; formed
by extensions of the walls of maternal and distal zooids. Ad-
ventitious avicularia only present; lateral-oral, proximal and
associated with the suboral mucro, or lateral and sutural, all
arising from the marginal areolar pores. Mandibles often ro-
bust, hooked and serrated, hinged on a complete crossbar.
Basal walls either with numerous septular pores, or radicular
chambers, sometimes in groups, or single, often very large,
occupying much of the basal wall. Radicular chambers giving
rise to cuticular rhizoids or a cuticular lamina, which covers
the basal surface of some erect portions of a colony.
Remarks
The basal rhizoids of the Petraliellidae enable the colonies to
strengthen and support or anchor erect portions of the colony,
and more importantly, to overgrow unstable substrata, such as
loose accretions of shell debris, coral fragments etc., masses
of hydroid rhizoids and algal stems, and sponges. The ability
to overgrow sponges is an important one, as these are usually
successful spatial competitors with encrusting bryozoans (e.g.
Nandakumar et al., 1993). The brightly coloured tentacles and
coelomic pigments in the Petraliellidae were first noted by
Maplestone (1882) and have been described by Bock (1982)
in Mucropetraliella.
In spite of the abundance of material of some species,
which may constitute a significant part of strand-line debris,
no morphometric or any other kind of analysis has ever been
made in order to establish the variation in character states of
any nominal species. There is little consensus on the morpho-
logical limits of species, and forms that are ‘rare’ may thus
be rigidly defined, whereas those that are widely distributed
are regarded as ‘common’ and have considerable latitude in
character states accepted in the literature. The apparent sim-
ilarities in ovicells, frontal shields and avicularia has resulted
in generic characters relying almost exclusively on those of
orifice calcification. Some of the difficulties in assessing these
were briefly discussed by Cook & Chimonides (1981).
Material examined
The majority of the cited material examined for this study
is deposited in the Bryozoa Collection of the Department
of Zoology, The Natural History Museum, London (prefixed
by BMNH). Material from the Australian Museum, Sydney,
Australia (prefixed by AM) and the Museum National
d’Histoire Naturelle, Paris, France (prefixed by MNHM) was
also examined. All species are illustrated with scanning elec-
tron micrographs of uncoated specimens, imaged using back-
scattered electrons.
Key to the Petraliellidae from Queensland
1a. Autozooids with rounded orifices; suboral avicularium,
with associated mucro or lacking; with lateral and/or
median denticles (with accompanying sinuses) ....... 2
1b. Autozooid with subrectangular orifices; suboral avicu-
larium and mucro lacking; with lateral and median
denticles (and accompanying sinuses) or smooth (i.e. no
denticles or sinuses) proximally; condyles present. ......
........................................Petraliella 4
2a. Oral spines present; symmetrical lateral and median
denticles present; suboral mucro with avicularium usu-
ally present; large lateral oral avicularia present or
lacking ...........................Mucropetraliella 3
2b. Oral spines absent; proximal denticles paired, unequal,
forming a sinus, obscured by a suboral avicularium; a
reduced suboral mucro .........Sinupetraliella litoralis
3a. Oral spines 8–9; suboral mucro small; very large
lateral avicularia common, directed proximo-laterally
........................................M.bennetti
3b. Oral spines 6–8 (usually 6); suboral mucro large; large
lateral avicularia on some autozooids ....... M.serrata
3c. Oral spines 4; suboral mucro very small, associated avicu-
larium large; no lateral oral avicularia .....M. tuberosa
4a. Autozooid orifices subrectangular and smooth (i.e. no
denticles or sinuses) ............................... 5
4b. Autozooid orifices with two or more proximal denticles
(with associated sinuses) ...........................6
5a. Autozooids large (length >1.00 mm); orifice as wide as
long, conspicuous condyles; avicularia lateral oral, single
or paired, acute, directed distally; ovicell prominent; basal
radicular chambers often single, small....P. crassocirca

Petraliellid bryozoans from Queensland 321
Figure 1 A, B, Petraliella bisinuata (Smitt, 1873), BMNH 1932.3.7.63, Off Havana, Cuba. A, two autozooids, note the size and relative position
of the median and lateral denticles (cf. P. buski). B, group of autozooids, note the shape of the proximolateral, distally directed
single, or paired, avicularia (cf. P. buski). C, D, Petraliella marginata (Canu and Bassler, 1928), BMNH 1961.11.2.37, south pass of
Mississippi River, Gulf of Mexico. C, group of autozooids, note the obvious articulatory condyles present in each primary orifice.
D, group of autozooids, note the proximolaterally directed lateral oral avicularia, and the distolaterally directed frontal avicularia.
E, F, Mucropetraliella loculifera Harmer, 1957, Paratype BMNH 1963.9.8.85, Badjo Bay, W. Flores. E, primary orifice, note the
occlusor-laminae, particularly obvious on the right, the proximally hooked lateral denticles, and the wide distolaterally pointed
median denticles. F, group of autozooids, note the complete ovicell (top, slightly right of centre) next to an enlarged proximally
directed frontal avicularium, suboral mucros, and numerous supernumerary frontal avicularia. A, E, scale bar 100 µm; B–D, scale bar
500 µm; F, scale bar 200 µm.

322 K. J. Tilbrook & P. L. Cook
5b. Autozooids large (length >1.00 mm); orifice longer than
wide, with minute condyles; avicularia lateral oral, single,
small, rounded, directed laterally or absent; ovicell, with
flat frontal calcification, immersed in frontal shield of
distal autozooid; basal pores small and numerous cover-
ing entire basal surface ......................P.magna
5c. Autozooids smaller (length <1.00 mm); orifice wider
than long, with robust condyles; avicularia lateral oral,
single or paired, small, oval, directed laterally; ovicell
prominent; basal radicular chambers often single, very
large.................................P.dorsiporosa
6a. Proximal sinus single, symmetrical, medial with a pair of
lateral denticles; condyles not visible; lateral oral avicu-
laria paired, small ....................... P.concinna
6b. Proximal sinuses paired, a median denticle and a pair of
lateral denticles; condyles minute, triangular; avicularia
triangular, single or paired, distal oral, directed proximo-
laterally or proximal oral, directed disto-laterally .......
............................................P. b u s k i
6c. Proximal sinuses multiple (average 5) with corresponding
denticles; condyles not visible; avicularia single or paired,
lateral oral, curved, directed distally or absent from large
areas ..................................P.dentilabris
Genus Petraliella Canu and Bassler, 1927
Petraliella Canu and Bassler, 1927: 5; 1929: 49,255.
Petraliella: Harmer, 1957: 692.
Hippopetraliella Stach, 1936: 369.
Hippopetraliella: Harmer, 1957: 700.
TYPE SPECIES: Escharella bisinuata Smitt, 1873.
Diagnosis
Orifices subrectangular proximally, rounded or subrectangular
distally, with lateral indentations. Proximal border smooth or
with symmetrical lateral and proximal denticles and single
median, paired lateral or multiple proximal sinuses. Condyles
present, minute triangular or large and robust. Lateral oral
avicularia only. No proximal mucro or suboral avicularium
complex. Spines absent.
Remarks
Petraliella bisinuata (Figs 1A,B) has been fairly thoroughly
described from the coast of Florida and the Gulf of Mexico
(Canu & Bassler, 1928). The nominal species has been reported
from the East Indies and northern Australia. This bipartite
distribution, together with correlated differences in character
states, suggests that the enormously wide distribution given by
Harmer (1957) should be modified, following Stach (1936),
see below.
Petraliella as diagnosed herein includes all species
formerly assigned to the genus Hippopetraliella Stach, 1936,
which is therefore a junior synonym of Petraliella.Exam-
ination of material assigned to Lepralia dorsiporosa Busk,
1884 (the type species of Hippopetraliella) including the type
material, shows that in some autozooids the proximal border
possesses a wide median denticle with paired lateral denticles
and shallow lateral sinuses. The usual condition is a smooth
proximal orificial border. However, examination of the prox-
imal border from inside shows that rudimentary lateral sinuses
are present in some autozooids which show no evidence of
these structures from the outside, i.e. frontally. In extreme
cases the proximal border of Busk’s species with denticles and
sinuses is similar to Mucropetraliella valdemunita Harmer,
1957. Harmer’s species is here designated a junior synonym
of Petraliella dorsiporosa (Busk). The presence of supernu-
merary avicularia on the frontal shield of Harmer’s species can
also be seen in older parts of colonies of P. dorsiporosa.The
number and character of the radicular chambers in specimens
assigned to the two species is identical. Harmer (1957) also
described, in both M.valdemunita and P. dorsiporosa, the pres-
ence of ‘two lobes’ of frontal wall calcification that surround
the primary orifice, but do not meet distal to it, leaving a small
proximal pocketing of the distal zooidal wall that touches the
distal border of the primary orifice (Fig. 6A). This feature of
lateral lobes of frontal shield surrounding the primary orifice is
also seen in other species of Petraliella but in no other species
is the pocketing so pronounced (except perhaps P. crassocirca:
Fig. 4B), rather the lobes generally run almost seamlessly into
the distal border of the orifice (e.g. P. concinna:Fig.3A;or
P. dentilabris: Fig. 5A), or join distal to the orifice (P. magna:
Fig. 7A).
The presence of articulatory condyles has not been noted
previously in the genus Petraliella due primarily, it would
seem, to their minute size in species such as P. bisinuata and P.
buski Stach, 1936. However, they have always been described
in species formerly belonging to Hippopetraliella due to their
greater size and robust appearance. Condyles have not been
observed in P. dentilabris (Ortmann, 1892) and P.concinna
(Hincks, 1891).
Hippopetraliella tahitiensis Leca & d’Hondt, 1993 from
French Polynesia, which was later described as Hippopodina
viriosa Tilbrook, 1999 should now be referred to as Hippo-
podina tahitiensis (Leca & d’Hondt, 1993). Leca & d’Hondt
(1993) illustrated a number of autozooidal mandibles from the
collections of the Natural History Museum, London.
Petraliella buski Stach, 1936
Figs 2A–D
Mucronella bisinuata Busk, 1884 (not Smitt, 1873): 157,
pl. 19, fig. 5.
Mucronella bisinuata (not Smitt): Kirkpatrick, 1890: 612
Petraliella bisinuata (not Smitt): Livingstone, 1927: 66;
Harmer, 1957 (in part): 696, pl. 44, figs 6, 7.
Petraliella buski Stach, 1936: 368.
Petraliella arafurensis Stach, 1936: 368, fig. 10.
Material examined
LECTOTYPE (here chosen): BMNH 1887.12.9.624 (Type of
Mucronella bisinuata Smitt sensu Busk, 1884) ‘Challenger’
Stn 190, S. of New Guinea, 8◦56S, 136◦5E, 49 fathoms
(90 m).
PARALECTOTYPES (here chosen): BMNH 1887.12.9.625,
626, (Paratypes of Mucronella bisinuata Smitt sensu Busk,

Petraliellid bryozoans from Queensland 323
Figure 2 A–D, Petraliella buski Stach, 1936. A, C, D, Paralectotype BMNH 1944.1.8.299, ‘Challenger’ Stn 190, Arafura Sea. B, AM U.510,
Thursday Island, Torres Strait. A, primary orifice, note the size and relative position of the median and lateral denticles (cf. P.
bisinuata), and the orientation of the distal oral avicularium. B, group of autozooids, including three ovicellate zooids. C, group of
autozooids from close to growing edge, note the proximolaterally directed distal oral avicularia. D, basal surface of several zooids
showing distally positioned radicular chambers. A, scale bar 100 µm; B, C, scale bar 200 µm; D, scale bar 400 µm.
1884), (locality data as above); BMNH 1899.7.1.4960, BMNH
1944.1.8.299, (Syntypes of Mucronella bisinuata Smitt sensu
Busk, 1884), (locality data as above).
OTHER MATERIAL EXAMINED: AM U510 (Holotype and
paratypes of Petraliella arafurensis Stach, 1936), Thursday
Island, Torres Strait; BMNH 1882.2.23.497–506, Arafura
Sea, 32–36 fathoms (58–66 m), Voyage ‘Alert’; BMNH
1890.3.24.34, Albany Passage, Stn 8, Torres Strait, Haddon
Coll.; BMNH 1999.3.9.3, Torres Strait, Haddon Coll.; BMNH
1963.9.8.46, ‘Siboga’ Stn 163, Seget, N. end of New Guinea,
29 m; BMNH 1999.11.8.11, ‘Siboga’ Stn 162, off Loslos
Island, N. end of New Guinea, 18 m; BMNH 1963.9.8.45,
‘Siboga’ Stn 274, off Jedan, Aru Islands, 57 m; BMNH
1892.1.28.65, Baleine Bank, NW Australia, 10–15 fathoms
(18–27 m), P.W. Bassett-Smith Coll.; BMNH 1892.1.28.69,
Holothuria Bank, NW Australia, 15 fathoms (27.5 m), P.W.
Bassett-Smith Coll.; BMNH 1944.1.8.300, Kobe, Japan, 8–50
fathoms (15–91 m), ‘Challenger’ Coll..
Description
Colony semi-encrusting, sometimes erect and tubular. Auto-
zooids polygonal, separated by a shallow groove (c.0.85×
0.50 mm), frontal shield uniformly perforate with large pores;
marginal pores indistinct, lateral walls distinct. Primary orifice
constricted laterally, with paired lateral denticles and paired
proximal sinuses flanking an anvil-shaped median denticle ap-
proximately half the width of the proximal border; minute
triangular condyles present. Oral avicularia, often numerous;
usually single or paired distal to the orifice, orientated prox-
imolaterally; others lateral and proximolateral to orifice, dir-
ected randomly. Rostra elongate triangular, serrated distally;
mandibles triangular, with central sclerite; hooked termin-
ally; crossbar complete. Other avicularia, similar in shape and
size to oral avicularia, produced on the frontal shield later in
ontogeny, randomly orientated. Ovicells prominent, uniformly
perforate with numerous small pores, secondary calcification
producing a border around the aperture and an imperfor-
ate patch frontally. Basal radicular chambers may be very

324 K. J. Tilbrook & P. L. Cook
large or smaller and supplemented by uniporous septular
pores.
Remarks
Petraliella buski is characterised by its pair of lateral denticles,
pair of lateral sinuses and anvil-shaped median denticle, as well
as its randomly oriented elongate triangular avicularia with a
serrated rostrum. It differs from P. dentilabris, which has mul-
tiple median denticles and sinuses and oral avicularia that are
often slightly curved but always distally directed. P.buski also
produces numerous randomly oriented avicularia, a feature not
observed in P. dentilabris. It differs from P. concinna,which
has a single median sinus, a pair of lateral denticles and oral
avicularia that are oval and directed laterally. P. b u s k i differs
from P. dorsiporosa,P. magna and P. crassocirca in having a
median and lateral denticles and lateral sinuses, whereas the
latter three species have entire proximal orificial margins.
Stach (1936) introduced the name Petraliella buski
for Busk’s (1884) ‘Challenger’ specimens of Mucronella
bisinuata (not Smitt, 1873) from the Arafura Sea, without,
however, examining any of the ‘Challenger’ material. He also,
somewhat confusingly, introduced the name P.arafurensis
for specimens of a closely similar species, housed in the Aus-
tralian Museum, from Thursday Island, Torres Strait, off north-
ern Queensland (AM U510). Included in his concept of P.
arafurensis was the material listed, but not described, by Kirk-
patrick (1890), also from the Torres Straits, which may also be
regarded as potential paralectotype material, although, again,
Stach did not actually examine the specimens. Stach’s (1936)
introductions were therefore somewhat unorthodox; but type
material for both of his species exists in museum collections
and is therefore available for revision. Having examined ma-
terial from both the Torres Strait and Arafura Sea and finding
them to be identical, they are all here assigned to Petraliella
buski. It appears Harmer (1957) was correct in regarding the
differences in avicularian characters between P. b u s k i and P.
arafurensis as being due to ontogenetic state only.
Although Harmer (1957) did not accept Stach’s subdivi-
sion of “Petraliella bisinuata”, there are sufficient differences
between the completely isolated western Atlantic and western
Pacific populations to maintain their taxonomic separation.
The numerous circumoral avicularia in P. bu s k i are present
quite early in ontogeny (cf. Harmer, 1957). The distal pair with
proximal orientation are present frequently enough to distin-
guish P.buski (see Fig. 2C) from P.bisinuata, where the oral
avicularia originate proximolaterally and are always distally
directed. P. bisinuata from the Gulf of Mexico also has more
prominent lateral denticles and a far narrower median denticle
(see Fig. 1B). The basal septular pores of P.bisinuata often
include one distal chamber with paired secondary chambers
(see Canu & Bassler, 1928: pl. 16, fig. 2). The radicular cham-
bers in P.buski are very large, sometimes occupying almost
the entire basal wall area (see Harmer, 1957: pl. 44, fig. 6).
It may be noteworthy that neither Canu & Bassler (1929)
(Philippines region) nor Waters (1909, 1913) (western Indian
Ocean) described a species similar to Petraliella buski des-
pite its presence from northwest to northeast Australia, and
Indonesia to Japan. The northwest Australian material differs
slightly in colour when dried from that found in Queensland
and the Arafura Sea: it is a dark orange as opposed to a beige
brown colour.
Petraliella concinna (Hincks, 1891)
Figs 3A–D
?Lepralia (Schizoporella) sp.? Haswell, 1881: 39.
Schizoporella concinna Hincks, 1891: 289 (154), pl. 6,
fig. 2; 1893: 146 (212).
Hippopetraliella concinna: Harmer, 1957: 701.
Material examined
HOLOTYPE: BMNH 1899.5.1.1019, Port Denison,
Queensland.
OTHER MATERIAL EXAMINED: BMNH 2001.7.25.1,
Holborn Island, Port Denison, Queensland, E. C. Jelly; BMNH
2001.7.25.2, Holborn Island, Port Denison, Queensland,
W. A. Haswell Coll.; BMNH 1866.6.22.10, East Australian
coast, 77 m.
Description
Colony semi-encrusting to erect, unilaminar. Autozooids rect-
angular or polygonal (c.1.0×0.5 mm); frontal shield uni-
formly perforated by large pores; marginal pores and lateral
walls distinct. Primary orifice subrectangular, thickened prox-
imally with a rounded, median sinus, flanked by two very
small lateral denticles. Avicularia lateral oral, often paired,
small, oval, with small rounded mandibles, laterally directed,
the distal ends of the rostra are minutely denticulate; crossbar
complete. Other small sutural avicularia occasionally present,
similar to oral avicularia, directed perpendicular to the lat-
eral wall, prevalent in the proximity of ovicells. Ovicell wide,
prominent, uniformly perforate with minute pores, with finely
tuberculate frontal and distinct, raised marginal rim. Basal ra-
dicular chambers, small, distal and deeply immersed.
Remarks
Petraliella concinna is characterised by its subrectangular ori-
fice, single, median sinus and small oval, often paired, lateral
oral avicularia that are laterally directed. It differs from both
P. b u s k i and P. dentilabris which have two or several proximal
sinuses respectively and far longer avicularia, which are large,
triangular and distolaterally or randomly oriented in P. b u s k i ,
but large, curved and distally oriented in P. dentilabris.P.con-
cinna differs from P. dorsiporosa,P. magna and P.crassocirca
in having a median sinus, whereas these three species have an
entire proximal orificial border.
Specimens of Petraliella concinna have rarely been re-
ported. Stach (1936) did not record it among collections of Pet-
raliellidae from Queensland, nor did Hastings (1932) among
specimens from the Great Barrier Reef, although it has since
been recorded from Heron Island (Tilbrook, unpublished data).
If it is the species mentioned by Haswell (1881) then the lack of
records seems odd as he describes it as ‘a species ...common
on the Australian coast’. Hincks’ (1891) colonies had no

Petraliellid bryozoans from Queensland 325
Figure 3 A–D, Petraliella concinna (Hincks, 1891). A, C, Holotype BMNH 1899.5.1.1019, Port Denison, Queensland. B, D, BMNH 1866.6.22.10,
East Australian coast. A, primary orifice, note the single medial sinus and paired lateral denticles, and the laterally directed lateral oral
avicularia. B, group of ovicellate zooids, note numerous supernumerary frontal avicularia. C, group of autozooids. D, basal surface of
several zooids showing distally positioned radicular chambers. A, scale bar 100 µm; B, D, scale bar 400 µm; C, scale bar 500 µm.
ovicells, but ovicells are present in the material from the East
Australian coast.
Specimen BMNH 2001.7.25.1 is dried and has no rhiz-
oids present. The radicular chambers are deeply immersed
and lack the raised rim found in Petraliella dorsiporosa and
Mucropetraliella serrata.
This species is only known from the Great Barrier Reef.
Petraliella crassocirca Canu & Bassler, 1929
Figs 4A–C
Lepralia crassa Thornely, 1912: 150, pl. 8, figs 9, 9a.
(Preoccupied Reuss, 1874.)
Petraliella crassocirca Canu & Bassler, 1929: 257, pl. 23,
figs 4–9; text-figs 105, A–E, 106, W.
Hippopetraliella crassocirca: Harmer, 1957: 703, pl. 45,
figs 4,7–9; text-fig. 61.
Cheiloporina campanula Hayward & Ryland, 1995: 555,
figs 10E, F.
Material examined
HOLOTYPE: USNM 8001, ‘Albatross’ Stn D.5579, Sibutu
Island, Darvel Bay, Borneo, 4◦5415N, 119◦0952E,
175 fathoms (320 m).
PARATYPE: BMNH 1931.12.30.79 (locality data as above).
OTHER MATERIAL EXAMINED: BMNH 1997.10.6.21,22,
Carter Reef, Great Barrier Reef, 50 feet; BMNH 1963.9.8.69,
BMNH 1999.7.20.6,7, ‘Siboga’ Stn 315, Paternoster Is-
lands, N. of Sumbawa, 0–36 m; BMNH 1963.9.8.64,66,
BMNH 1999.7.20.7, ‘Siboga’ Stn 144, S. of Halmahera,
Djilolo, 0–45 m; BMNH 1963.9.8.63,67,68, ‘Siboga’ Stn 81,
Borneo Bank, 40–50 m; BMNH 1936.12.30.194, Cargados, 30
fathoms (55 m), Thornely Coll..
Description
Colony encrusting. Autozooids generally rectangular or
polygonal (c.1.10×0.70 mm); frontal shield flat, uniformly
perforate with medium pores; marginal pores and lateral walls

326 K. J. Tilbrook & P. L. Cook
Figure 4 A–C, Petraliella crassocirca Canu & Bassler, 1929. A, C,
Holotype USNM 8001, Darvel Bay, Borneo. B, BMNH
1997.10.6.21,22, Carter Reef, Great Barrier Reef. A, group
of autozooids, note the distally directed lateral oral
setiform avicularia. B, group, including two ovicellate
zooids. C, basal surface showing several radicular
chambers. A, C, scale bar 500 µm; B, scale bar 250 µm.
distinct. Primary orifice subrectangular, as wide as long,
constricted laterally one-third the distance from the straight
proximal border; condyles conspicuous. Avicularia variable
in size, but generally large, single or paired, lateral to orifice,
distally directed; mandible acute, setiform, curved basally at
distal end; crossbar complete. No sutural avicularia observed.
Ovicells prominent, lightly calcified, recumbent on frontal
wall of distal autozooid, minutely porous with a distinct,
raised marginal rim. A single small radicular chamber placed
distally.
Remarks
The setiform, distally directed, lateral oral avicularia char-
acterise Petraliella crassocirca and distinguish it from all
other species of Petraliella described here. Harmer (1957) de-
scribed sutural avicularia in Thornely’s (1912) material from
Cargados (NNE of Mauritius). One of Thornely’s specimens
(1936.12.30.194) has a large number of frontal avicularia,
which although not strictly sutural, occur especially in areas of
secondary calcification and close to ovicells. These have not
been observed in the Queensland material. The lateral oral avi-
cularia in Thornely’s material are also more distally positioned,
directed distomedially around an orifice with a narrower distal
border. The size of the avicularia varies greatly both within
and between colonies throughout the range of this species.
Hayward & Ryland (1995) described a new species
within the genus Cheiloporina (Canu & Bassler, 1923) from
non-ovicellate material, which is here recognised as Petraliella
crassocirca.
Petraliella crassocirca appears to be present along the
length of the Great Barrier Reef, extending through Indo-
Malaysia, as far west as Cargados in the western Indian
Ocean.
Petraliella dentilabris (Ortmann, 1892)
Figs 5A–C
Lepralia dentilabris Ortmann, 1892: 670, text fig. [no
number]
Petraliella dentilabris: Harmer, 1957: 705.
Petralia chuakensis Waters, 1913: 518, pl. 70, figs 10–14.
Petralia chuakensis: Livingstone, 1926: 99; Hastings, 1932:
436.
Hippopetraliella (Serripetraliella)chuakensis hastingsae
Stach, 1936: 371, figs 6A, 12A, B.
Petraliella chuakensis: Harmer, 1957: 698, pl. 44, figs 11,
13; Ryland, 1974: 342; Winston & Heimberg, 1986: 16,
figs 31, 32.
Material examined
BMNH 1915.10.20.9, Chuaka, Zanzibar, Crossland Coll.
(Syntype of Petralia chuakensis Waters, 1913); BMNH
1932.4.20.56,123, Low Island, off Port Douglas, Queensland,
Hastings; BMNH 2000.4.11.15,30, Green Island, Queensland,
02.07.72; BMNH 2000.4.11.16,29, Cairncross Island, Great
Barrier Reef, 15.06.72; BMNH 2000.4.11.17,28, Suva Barrier
Reef (east), Fiji, 29.03.79; BMNH 1963.9.8.51,52, ‘Siboga’
Stn 89, Kanuingen, Ketjil, East Borneo, 0–11 m; BMNH
1999.3.9.4, ‘Siboga’ Stn 89, Kanuingen, Ketjil, East Borneo,
0–11 m; BMNH 2000.4.11.22,23, Papua New Guinea; BMNH
2000.4.11.24, Palau.

Petraliellid bryozoans from Queensland 327
Figure 5 A–C, Petraliella dentilabris (Ortmann, 1892), BMNH
1915.10.20.9, Chuaka, Zanzibar. A, primary orifice, with
associated distally directed lateral oral avicularium. B,
group of ovicellate zooids, note the strongly curved
avicularian rostra and abundant proximal denticles in the
primary orifices. C, basal surface showing large radicular
chambers. A, scale bar 100 µm; B, C, scale bar 500 µm.
Description
Colonies encrusting to semi-encrusting. Autozooids in longit-
udinal rows, rectangular or polygonal, separated by a shallow
groove (c.0.90×0.70 mm); frontal shield uniformly perforate
with large pores; marginal pores and lateral walls becoming
indistinct with ontogeny. Primary orifice as wide as long, with
5–6 proximal denticles, separated by small sinuses, along the
otherwise almost straight proximal border. Condyles not ob-
served. Frontally pointing lappets may form either side of the
orifice accompanied by slight lateral indentations. Oral avicu-
laria single or paired, lateral, elongated, distally directed, the
distal end of the curved rostrum raised from the frontal shield;
mandibles strongly curved, almost S-shaped; complete, delic-
ate crossbar. No frontal or sutural avicularia observed. Ovi-
cells prominent, uniformly perforate, with numerous small
pores, and finely tuberculate, an imperforate border around
the aperture and distinct, raised marginal rim. Basal radicular
chambers, median and distal, may be very large.
Remarks
Petraliella dentilabris is characterised by the denticulate prox-
imal border to its primary orifice and by the elongate, curved
lateral oral avicularia. It differs from P.buski in having mul-
tiple proximal denticles (Fig. 5A), rather than two lateral
denticles and an anvil-shaped median denticle. The lateral
oral avicularia are distally directed and curved, not proximo-
laterally directed and straight as are the distal oral avicularia
common in P. b u s k i .Petraliella dentilabris differs from P. con-
cinna which only has a single median proximal oral sinus and
small, oval avicularia that are laterally directed. P.dentilabris
differs from P. dorsiporosa,P. magna and P. crassocirca in
having a denticulate proximal orificial margin, the latter three
species have a smooth margin.
Ortmann (1892) introduced Lepralia dentilabris for a
species found off Dar es Salaam, Tanzania. Apart from
Harmer’s (1957) brief mention of the species it appears to have
been forgotten until this day. Ortmann’s material is unavailable
for examination but his description and figure, although crude,
is easily identifiable as the species later described by Waters
(1913) as Petralia chuakensis from Zanzibar, the large island
off the coast of Tanzania and opposite Dar es Salaam. We feel
justified in regarding Petraliella dentilabris (Ortmann, 1892)
as the senior synonym of Petraliella chuakensis (Waters, 1913)
as the two species appear identical from their descriptions and
illustrations and the two type localities are very close.
Stach (1936) introduced the subgenus Serripetraliella for
Petraliella chuakensis, and regarded Hastings’ (1932) undes-
cribed material from the Great Barrier Reef as a variety, on
the basis of differences in its lateral and basal septular pores.
Stach’s figure 12A also appears to show an avicularium with far
less curvature than that depicted by other authors. The avicu-
laria appear to increase in length and curvature with astogeny.
The Low Island material has smaller radicular chambers than
the East African material, often supplemented by several very
small chambers. One specimen (BMNH 1932.4.20.56) also
lacks the characteristic lateral oral avicularia; however, the
primary orifice is identical to Water’s (1913) species, includ-
ing the presence of lateral oral lappets. Harmer (1957) did
not regard Stach’s Serripetraliella chuakensis hastingsae as
either generically different from Petraliella or separable from
P. chuakensis (i.e. P. dentilabris).

328 K. J. Tilbrook & P. L. Cook
Stach’s (1936) concept of Serripetraliella included a
somewhat heterogeneous group of species. Harmer (1957)
noted that Hippopetraliella marginata (Canu & Bassler, 1928)
(see Figs 1C,D), from the Gulf of Mexico, which was included
by Stach (1936) in Serripetraliella, had large articulatory
condyles, and that the proximal orificial serrations were not al-
ways present (Cheetham & Sandberg, 1964). Canu & Bassler’s
species is here included in the genus Petraliella.
The measurements given by Winston & Heimberg (1986)
for Petraliella dentilabris (as P. chuakensis) in their figs. 31
and 32 are not consistent with the scale provided, or with those
of other specimens.
Petraliella dentilabris has an extensive distribution, from
the East African coast, through the East Indies to northern
Queensland and Fiji.
Petraliella dorsiporosa (Busk, 1884)
Figs 6A–C
Lepralia dorsiporosa Busk, 1884: 143, pl. 18, figs. 4, 4b.
Lepralia dorsiporosa: Kirkpatrick, 1890: 612.
Hippopetraliella dorsiporosa: Stach, 1936: 369, fig. 11;
Harmer, 1957: 700, pl. 45, figs 1–3 (cum syn)
Mucropetraliella valdemunita Harmer, 1957: 711, pl. 46,
figs 1, 2.
Material examined
HOLOTYPE: BMNH 1897.12.9.569, ‘Challenger’ Stn 186,
Cape York, 10◦30S, 142◦18E, 15 m.
PARATYPES: BMNH 1897.12.9.568, BMNH 1944.1.8.274
(locality data as above).
OTHER MATERIAL EXAMINED: BMNH 1890.3.24.26,
Albany Passage, Stn 8, Torres Strait (Kirkpatrick); BMNH
1890.7.23.52, Murray Islands, Torres Strait, 15–20 fathoms
(27–36 m), A.C.Haddon; BMNH 1896.3.24.38, Murray Is-
lands, Torres Strait; BMNH 1963.9.8.53,58, Torres Strait,
Haddon Coll.; BMNH 1882.2.23.512–521, Port Darwin, 8–12
fathoms (15–30 m); BMNH 1892.1.28.64, Holothuria Bank,
N.W. Australia, 24–34 fathoms (44–62 m), Bassett-Smith
Coll.; BMNH 1963.9.8.55, ‘Siboga’ Stn 315, Paternoster
Islands, N. of Sumbawa, Flores Sea, 0–36 m; BMNH
1963.9.8.54, ‘Siboga’ Stn 277, Damar Island, Banda Sea, 0–
45 m.
Description
Colonies semi-encrusting, or erect, tubular, often extensive.
Autozooids hexagonal or polygonal (c.0.90×0.70 mm),
frontal shield flat, uniformly perforate with large pores; mar-
ginal pores indistinct, lateral walls distinct. Primary orifice
wider than long, constricted laterally one-third of the distance
from a straight proximal border; condyles large, robust, con-
spicuous. Oral avicularia lateral, single or paired, small, oval,
directed laterally; rostrum minutely serrated distally; mand-
ibles small, rounded; robust complete crossbar. No frontal
or sutural avicularia observed. Ovicells prominent, recumbent
on frontal wall of distal autozooid, minutely porous and
tuberculate, partially obscuring the maternal orifice. Basal
Figure 6 A–C, Petraliella dorsiporosa (Busk, 1884). A, Paratype
BMNH 1944.1.8.274, ‘Challenger’ Stn 186, Cape York. B, C,
Holotype BMNH 1897.12.9.569, ‘Challenger’ Stn 186, Cape
York. A, primary orifice showing articulatory condyles and
lateral oral avicularium. B, group of autozooids, frontal
membrane and opercula intact. C, basal surface with
radicular chambers of varying sizes. A, scale bar 50 µm; B,
C, scale bar 500 µm.
radicular chambers, placed distally, often single, very
large, although several very small chambers may accompany
them.

Petraliellid bryozoans from Queensland 329
Remarks
Petraliella dorsiporosa is distinguished from P.magna by its
subrectangular orifice with an entire proximal border, promin-
ent, well-developed condyles, and large radicular chambers. It
is distinguished from P. crassocirca by its small, oval, laterally
directed avicularia. Petraliella crassocirca has acute distally
directed avicularia. Petraliella dorsiporosa is also character-
ised by the distal wall of each autozooid which meets the distal
border of the orifice with a U-shaped proximal fold. Petraliella
buski,P. dentilabris and P. concinna are distinguishable from
this species as they all have lateral and or median denticles and
associated sinuses.
Petraliella dorsiporosa was first described from Cape
York, Queensland and was subsequently recorded from Albany
Passage, Darnley Island and Murray Island, all from neigh-
bouring localities in the Torres Strait. Specimens from Holo-
thuria Bank and northwestern Australia are here assigned to P.
dorsiporosa, as are those from the East Indies that had been re-
ferred to P.dorsiporosa by Stach (1936) and by Harmer (1957).
Two of Harmer’s (1957) specimens from Eastern Indonesia,
BMNH 1963.9.8.54 (Damar Island, Banda Sea) and BMNH
1963.9.8.55 (Paternoster Island, Flores Sea) differ subtly from
the normal form of P.dorsiporosa in having a small pair
of lateral sinuses and denticles as well as obvious condyles.
Leca & d’Hondt (1993: Fig. 2a) figured an operculum of the
former specimen. These specimens also possess sutural avicu-
laria and have smaller radicular chambers, attributes of Mucro-
petraliella valdemunita Harmer, 1957 from Waigeo Island,
also in Eastern Indonesia. M. valdemunita is here regarded as
a junior synonym of P. dorsiporosa (see generic remarks for
Petraliella above).
Petraliella dorsiporosa is found from northeastern to
northwestern Australia and Eastern Indonesia.
Petraliella magna (d’Orbigny, 1852)
Figs 7A–F
Semieschara magna d’Orbigny, 1852: 367 (in part).
Hippopetraliella magna: Harmer, 1957: 701, pl. 45,
figs 5,6 (cum syn); Cook & Chimonides, 1981: 121, text
figs 7C,D; Hall, 1984: 62, pl. 3, fig. D; Cook and Bock,
2002: 1611, figs 15–17.
Lepralia japonica Busk, 1884: 143, pl. 17, figs 5, 5a.
Lepralia japonica: Waters, 1909: 149, pl. 13, figs 10–12.
Petralia japonica: Levinsen, 1909: 352, pl. 18, figs 5a,b;
Canu & Bassler, 1929: 254, pl. 23, figs 1–3; text figs
104A–G, 105G; Waters, 1913: 518; Livingstone, 1924:
197.
Petralia gigas Hincks, 1885: 255, pl. 9, fig. 8.
Material examined
LECTOTYPE (here chosen): MNHM 13629 (part), D´
etroit
de Malacca [Strait of Maluku, Eastern Indonesia], unmarked
glass vial.
OTHER MATERIAL EXAMINED: BMNH 1899.7.1.1433
(Holotype of Lepralia japonica Busk, 1884), Kobe, Japan,
8–50 fathoms (15–92 m), ‘Challenger’ Coll.; BMNH
1899.7.1.1432, BMNH 1887.12.9.565, BMNH 1934.2.16.19,
BMNH 1944.1.8.273, BMNH 1999.3.9.5 (Syntypes of Lep-
ralia japonica Busk, 1884), Kobe, Japan, 8–50 fathoms
(15–92 m), ‘Challenger’ Coll.; BMNH 1899.5.1.810 (Holo-
type of Lepralia gigas Hincks, 1885), Trincomalee, Sri
Lanka; BMNH 1899.7.1.169,270,1422,1424–1426, (Syntypes
of Lepralia gigas Hincks, 1885), Trincomalee, Sri Lanka;
BMNH 1986.7.30.2, Townsville, Queensland, 10–20 m;
BMNH 2000.4.11.2,3, Townsville, Queensland, strandline,
July, 1972; BMNH 2000.4.11.9,18, Caloundra, Queensland,
strandline, 17.07.72; BMNH 2000.4.11.1,4–6, Cleveland
Bay, Great Barrier Reef; BMNH 1999.7.19.1, Torres Strait;
BMNH 1882.2.23.557–46, Thursday Island, Torres Strait, 3–5
fathoms (5.5–9 m), HMS ‘Alert’; BMNH 1882.2.23.411–420,
Torres Strait, 10 fathoms (18 m); BMNH 1986.7.30.2, off
Townsville, Queensland, 10–15 m; BMNH 1896.2.28.1, N.W.
Australia, Saville Kent Coll.; BMNH 1930.9.22.4, Cape
Boilesu, N.W. Australia; BMNH 1963.9.8.59,60, Labuan
Pandam, Lombok; BMNH 1893.8.11.35, Macclesfield Bank,
China Sea; BMNH 1931.12.30.78, ‘Albatross’ Stn 5311,
off Pratas Island, China Sea, 88 fathoms (161 m); BMNH
1962.2.20.10, 23◦32N, 119◦35E, Formosa Strait; BMNH
1963.2.12.251, 23◦20N, 118◦30E, Formosa Strait, 17
fathoms (31 m) [Described by Levinsen, 1909]; BMNH
1878.1.10.15, South of Japan; BMNH 1899.7.1.1423, no
locality (Sri Lanka?); BMNH 1999.7.19.2, Sri Lanka,
Thornely Coll.; BMNH 1936.12.30.39, Sri Lanka, Thornely
Coll.; BMNH 1890.6.28.7, Pamban, Madras, India, shallow
water; BMNH 1963.9.8.62, Pamban, Madras, India, shallow
water; BMNH 1890.1.31.32, Madras, India; BMNH
1883.4.25.30–31, Karachi, Pakistan; BMNH 1959.11.4.6,
Karachi, Pakistan; BMNH 1888.1.25.32, Mauritius, 70
fathoms (128 m); BMNH 1963.9.8.61, Ghardaqa, Red Sea;
BMNH 1884.7.25.10, Aden; BMNH 1892.1.11.1, Muscat,
Persian Gulf; BMNH 1970.1.4.13, beach South of Thio,
Ethiopia/Eritrea?; BMNH 2000.4.11.19, Tanzania; BMNH
1899.7.1.130–132, Port Natal, South Africa.
Description
Colonies very large, semi-encrusting to erect, with bilaminar,
often tubular, expansions that branch and anastomose; dark vi-
olet in colour with red growing edges when alive. Autozooids
generally rectangular (c.1.10×0.60 mm), rounded distally,
frontal shield flat, with small tubercles, uniformly perforate
with medium pores; marginal pores and lateral walls distinct.
Primary orifice bell-shaped, longer than wide, with a roun-
ded anter and straight proximal border, constricted laterally,
minute condyles. Oral avicularia lateral, wanting or single, oc-
casionally paired, small, rounded laterally directed; mandible
semi-circular; crossbar complete. Ovicells unlike all others in
Petraliellidae; frontal finely tubercular, uniformly porous, flat,
depressed; brood cavity encroaching on frontal side of distal
autozooid, frequently remaining uncalcified late in ontogeny
of surrounding zooids. Embryos deep red in colour when alive.
Basal radicular chambers absent; replaced by numerous uni-
porous septular pores.

330 K. J. Tilbrook & P. L. Cook
Figure 7 A–F, Petraliella magna (d’Orbigny, 1852). A, B, BMNH 2000.4.11.1, Cleveland Bay, Great Barrier Reef. C–E, Lectotype MNHM 13629
(part), D´etroit de Malacca (Indonesia). F, BMNH 1963.9.8.60, Labuan Pandam, Lombok. A, autozooids and ovicellate zooid, note the
ovicell immersed in the frontal wall of the distal zooid. B, group of zooids. C, group of autozooids from close to the growing edge. D,
group of zooids from an older part of a colony, note the concavities left by broken ovicells (top, centre and right). E, basal surface of
several zooids showing numerous uniporous septular pores. F, inner surface of lateral walls, note several multiporous septular
pores. A, F, scale bar 200 µm; B–E, scale bar 500 µm.

Petraliellid bryozoans from Queensland 331
Remarks
Petraliella magna is characterised by its bell-shaped orifice,
those of both P. crassocirca and P. dorsiporosa being squarer
in outline. It is also distinguished by its unique ovicell, which
appears flattened, immersed in the frontal shield of the distal
autozooid, and the lack of radicular chambers which are re-
placed by numerous uniporous septular pores, for all intents
and purposes the whole basal wall is one large radicular cham-
ber. P. b u s k i ,P. dentilabris and P. concinna are distinguishable
from P. magna as they all have lateral and or median denticles
and associated sinuses.
D’Orbigny’s type material of Semieschara magna com-
prises two glass vials, each containing a separate species. The
vial marked with d’Orbigny’s number (MNHM 13629) con-
tains material of Petraliella dorsiporosa. The other unmarked
vial contains P. magna and is here chosen as the lectotype for
a number of reasons: the material in the two vials may have
been switched around over time; d’Orbigny (1852) described
his new species as the largest he knew and the zooidal dimen-
sions of the material in the unmarked vial are larger than that in
the marked vial; Waters (1913) recognised the conspecificity
of Busk’s (1884) Lepralia japonica with d’Orbigny’s species,
obviously referring to the material now in the unmarked vial
(Waters does mention that in one case [vial?] the material has
attributes similar to P. dorsiporosa).
Stach (1936: 364) mentioned Petraliella magna only in
passing and did not assign it to any of his new generic group-
ings.
The distribution of the nominal records of Petraliella
magna is extensive and examination of material from the
various populations reveals slight differences. These are not
considered great enough to warrant the designation of new
species from within its range of variation. The lateral oral
avicularia can look relatively large and raised in some colon-
ies, particularly at the colony edge; however these become
immersed with ontogeny. Some material from Sri Lanka and
Karachi (Pakistan) has a slightly greater orificial constriction
than material from other areas. These specimens also have im-
mersed ovicells whose frontal surface is slightly raised above
the level of the frontal shield of the distal zooid in which it
is imbedded. However, this may be due to the development
of ovicells on areas of encrusting autozooids rather than erect
areas of the colony. Other variations occur in the colony form:
differences in the diameters of the tubular expansions of the
colony can be seen, as can differences in the colour and thick-
ness of the frontal cuticle, even from a single location, e.g.
northwestern Australia, although the individual autozooids re-
main identical in morphology. These may all be ecophenotypic
variations.
Apparent delay in the completion of the ovicell dur-
ing ontogeny is frequent in the Petraliellidae (Bock, 1982;
Cook & Bock, 2002), but is particularly noticeable in Petrali-
ella magna. Canu & Bassler (1929) described the ovicells as
‘broken’, and Harmer (1957) as ‘due to a defective condition
in the ovary’. The early stages of ovicell development are seen
as large, rounded depressions in the frontal shield of the distal
zooid. This is later covered by a lamina emanating from one
of the proximal septular pores. The entire structure is covered
frontally by a thick cuticle, and even when calcified beneath
the cuticle, is never prominent, as are the ovicells of all other
species. The release of larvae, settlement and early astogeny
has been described by Cook & Bock (2002), and the ances-
trula resembles that of Mucropetraliella ellerii (MacGillivray,
1869) in having uncalcified prolongations which raise it above
the substratum, to which it is only intermittently attached. Like
the development of rhizoids originating from the zooid basal
walls, this appears to be an adaptation allowing the colonisa-
tion of unstable substrata.
Hall (1984) noted that Petraliella magna was ‘widely dis-
tributed in Cleveland Bay’ (north-east of Townsville), ‘where
it is a common component of benthic dredge samples’. Cook
& Bock (2002) also noted the large size of colonies found
as strand-line debris from near Townsville. However, the av-
erage zooidal dimensions of these colonies were consistently
at the lower end of the range of variation, even though some
autozooids exceeded 1.0 mm in length.
Petraliella magna has been recorded from the East In-
dies (Marcus, 1923), the Red Sea and East Africa (Waters,
1909, 1913), India and Sri Lanka (Hincks, 1885a, b; Thornely,
1905), Japan (Busk, 1884; Ortmann, 1889), the Philippine re-
gion (Canu & Bassler, 1929), and Queensland, Australia (Liv-
ingstone, 1924; Hall, 1984). Osburn’s (1952) recorded this
species from the Gulf of Mexico, describing material which
had no ovicells, condyles are not described, and its avicularia
differ from those of other specimens; it is not included in P.
magna here.
Genus Mucropetraliella Stach, 1936
Mucropetraliella Stach, 1936: 372.
Mucropetraliella: Harmer, 1957: 709.
TYPE SPECIES: Lepralia ellerii MacGillivray, 1869.
Diagnosis
Orifice with a median proximal denticle and paired lateral
denticles. Narrow, shelf-like condyles present. Suboral mucro,
with associated avicularium or avicularia usually present,
sometimes branched and complex. Oral spines present or ab-
sent.
Remarks
Mucropetraliella ellerii was originally described from Port
Phillip Bay, Victoria by MacGillivray (1869), who did not
figure his specimens until 1879. Stach (1936) illustrated the
interior morphology of zooids, but the only modern illustra-
tions are those of Bock (1982) and Gordon & Parker (1991).
M.ellerii is bright red in colour when alive and has very
small median and lateral denticles, a small proximal mucro
and avicularian complex, and no oral spines, although blunt
processes may develop lateral to the orifice. M. ellerii also
has large frontal avicularia, proximal to the mucro, which are
elongate oval in shape and proximally directed. The ovicell
is prominent, slightly crescentic in shape with an imperforate
proximo-frontal area.

332 K. J. Tilbrook & P. L. Cook
The presence of articulatory condyles has not been noted
previously in this genus. Most species, such as Mucropet-
raliella bennetti (Livingstone, 1926), M. serrata (Livingstone,
1926) and M.tuberosa (Busk, 1884), possess narrow shelf-like
ledges of calcification within the lateral edges of the primary
orifice. It is believed that these shelf-like structures, which ter-
minate distal to the lateral denticles, act as the resting place
for the operculum when closed, but that their proximal end
also acts as the fulcrum about which the operculum is able
to rotate on opening, i.e. the functional equivalent of artic-
ulatory condyles. These shelf-like structures may have been
ignored previously as they do not look similar to the condyles
seen in other genera of the family, e.g. Petraliella,andso
their function may have been overlooked. The only notable
exception to this is M. loculifera Harmer, 1957 (Figs 1E, F),
which possesses two obvious occlusor-laminae which house
the musculature that closes the operculum (Fig. 1E). It may
be that these occlusor-laminae are a more derived form of the
condyles described here for the first time.
Mucropetraliella bennetti (Livingstone, 1926)
Figs 8A, B
Petralia vultur var. bennetti Livingstone, 1926: 96, pl. 6,
figs 3–6.
Petralia vultur var. bennetti: Harmer, 1957: 720.
Mucropetraliella bennetti: Stach, 1936: 372.
Material examined
HOLOTYPE: AM U.2294, Ellison’s Reef, Great Barrier Reef,
8 fathoms (15 m).
PARATYPE: BMNH 1931.10.12.5, Ellison’s Reef, Great Bar-
rier Reef, 15 m, Paradise Coll. [Presented by the Australian
Museum; part of Livingstone’s material].
OTHER MATERIAL EXAMINED: BMNH 2000.4.11.25,
Tideaway Reef, Great Barrier Reef, 10m, 22.07.73; BMNH
2000.4.11.27, Carter Reef, Great Barrier Reef, 16 m, 25.06.73.
Description
Colony encrusting. Autozooids polygonal (c.1.20×
0.80 mm); frontal shields flat, uniformly perforate; marginal
pores indistinct, lateral walls distinct. Primary orifice longer
than wide; short, narrow shelf-like condyles laterally; small,
paired lateral denticles and a moderately wide median denticle
(approximately one-third width of orifice); seven to nine oral
spines (most commonly eight). Suboral mucro small, as-
sociated avicularium small, oval; rostrum minutely serrated
distally, mandible semicircular. Very long lateral avicularium,
with raised, serrated, parallel-sided rostrum, directed laterally
and proximally; mandible long, parallel-sided, curving bas-
ally; complete crossbar with a columella. Ovicells prominent,
minutely perforate, smooth. Single, small radicular chamber
distally, often accompanied by one or more minute chambers.
Remarks
The very long lateral avicularia, and the minute suboral mucro
distinguish Mucropetraliella bennetti from M.serrata and M.
Figure 8 A, B, Mucropetraliella bennetti (Livingstone, 1926),
Holotype AM U.2294, Ellison’s Reef, Great Barrier Reef. A,
primary orifice with suboral mucro and suboral
avicularium, note the median denticle, associated lateral
sinuses, and lateral denticles. B, two autozooids, note the
large proximolaterally directed frontal avicularia. A, scale
bar 100 µm; B, scale bar 200 µm.
tuberosa. These characters, in conjunction with the large num-
ber of oral spines, distinguish this species from all other species
of Mucropetraliella.M. vultur (Hincks, 1882) and M. serrata
have six spines, M.magnifica (Busk, 1884), M. neozelanica
(Livingstone, 1929), M. capricornensis (Tilbrook et al., 2001)
and M. tuberosa have four spines, and M. loculifera has two
to four spines. In other species of Mucropetraliella spines are
absent.
Mucropetraliella bennetti is known only from the Great
Barrier Reef.
Mucropetraliella serrata (Livingstone, 1926)
Figs 9A–D
Petralia vultur var. serrata Livingstone, 1926: 95, pl. 6,
figs 7–10.
Petralia vultur var. serrata: Hastings, 1932 (in part): 436,
text figs 14A–D.

Petraliellid bryozoans from Queensland 333
Figure 9 A–D, Mucropetraliella serrata (Livingstone, 1926). A, B, AM U.2297, Surprise Shoal, Great Barrier Reef. C, D, BMNH 1932.4.20.58, W.
of Low Island, Great Barrier Reef. A, primary orifice with suboral mucro and enlarged suboral avicularium, note the small
proximolaterally directed lateral oral avicularium, median denticle, lateral sinuses and lateral denticles. B, group of autozooids, note
the large proximolaterally directed frontal avicularia. C, group of zooids including several ovicellate zooids, note the small
supernumerary frontal avicularia. D, basal surface or several zooids showing circular radicular chambers. A, scale bar 100 µm; B, C,
scale bar 500 µm; D, scale bar 400 µm.
Mucropetraliella serrata: Stach, 1936: 372; Harmer, 1957
(in part): 718, pl. 46, fig. 8, Fig. 66 (cum syn).
Material examined
HOLOTYPE: AM U.2297, Surprise Shoal, between Cairns
and Townsville, Great Barrier Reef, 28 fathoms (51 m).
OTHER MATERIAL EXAMINED: BMNH 1931.10.12.6,
Peak Point, North Island, Queensland, 5.5–11 m; BMNH
1932.4.20.58, W. of Low Island, Great Barrier Reef, 11 m;
BMNH 1890.3.24.38, Murray Island, Torres Strait; BMNH
1963.9.16.2–5, Torres Strait, Haddon Coll.; BMNH
1986.7.30.3, off Townsville, Queensland, 10–20 m, mud and
shell bottom; BMNH 2000.4.11.26, Cleveland Bay, Great Bar-
rier Reef.
Description
Colony semi-encrusting, with erect laminar expansions. Auto-
zooids polygonal (c.1.00×0.70 mm); frontal shields flat,
uniformly perforate; marginal pores indistinct, lateral walls
distinct. Primary orifice longer than wide, very narrow shelf-
like ledge around anter, terminating midway along the lateral
border, small paired lateral denticles and a moderately wide
median denticle (less than one-third width of orifice); six oral
spines. Suboral complex prominent, including a large, blunt
mucro with an associated, elongate oval, ascending avicu-
larium; with a rostrum raised from the mucro, crossbar com-
plete with a small columella, mandible rounded terminally.
Numerous frontal and sutural avicularia produced later in on-
togeny, smaller than the mucronal avicularium, oval, randomly
directed. Large lateral avicularium, rostrum elongated, widen-
ing distally and curving basally, orientated proximo-laterally;
crossbar complete with a small columella. Ovicells promin-
ent, minutely perforate, smooth but often bearing groups of
protuberances of secondary calcification. A single radicular
chamber distally, often accompanied by one or more small
basal pores. Colonies are brilliant red when alive.

334 K. J. Tilbrook & P. L. Cook
Remarks
Mucropetraliella serrata is distinguishable from M. bennetti
by its larger suboral mucro, shorter and wider, large lateral
avicularia, and less numerous oral spines. Mucropetraliella
serrata does, however, have more oral spines than M. tuberosa
which only bears four; the latter species has no lateral avicu-
laria, only a large suboral avicularium.
Canu & Bassler (1929) described Petraliella falcifera
and P. philippinensis from the Philippines, both of which have
large, lateral avicularia, similar to Mucropetraliella serrata.
No details of oral spines were given in the original description,
or have been seen in the ‘co-type’ material deposited in the
Natural History Museum, London collections. Harmer (1957)
thought P. falcifera and P. philippinensis to be the same spe-
cies, an idea with which we must concur having examined
‘co-type’ material of both, P. philippinensis taking precedence.
M. serrata resembles M. loculifera in having supernumerary
avicularia and large, lateral avicularia. However, M. serrata
has six oral spines whereas M. loculifera has a maximum of
four. M. serrata has a narrower median denticle and also lacks
the occlusor laminae diagnostic of M. loculifera.
Both Hastings (1932) and Harmer (1957) assigned spe-
cimens from a wide area to M. serrata, and these varied con-
siderably in character from the Queensland material. Much
of their material has been re-examined, and is considered to
differ (most often with regard to attributes of the large frontal
avicularia) too much to be referable to M. serrata sensu stricto.
However, there are differences in character states even within
the Queensland material of M. serrata. For example, the speci-
men from Townsville (BMNH 1986.7.30.3) has a taller, more
erect mucro, with larger mucronal avicularia, than Hastings’s
specimen from Peak Point (BMNH 1931.10.12.6). There are
also slight differences in the width of the median denticle
within the material examined, but no more marked than the
width variations seen within certain colonies.
M. serrata sensu stricto appears to be confined to the
Queensland coast.
Mucropetraliella tuberosa (Busk, 1884)
Figs 10A–D
Lepralia tuberosa Busk, 1884: 143, pl. 17, fig. 7.
Lepralia tuberosa: Levinsen, 1909: 350, 351.
Material examined
HOLOTYPE: BMNH 1887.12.9.566, Port Jackson, New
South Wales, Australia, 35 fathoms (64 m), ‘Challenger’
Collection.
OTHER MATERIAL EXAMINED: BMNH 2001.4.11.1 (ex.
BMNH 1866.6.22.10 part), East Australian coast, 77 m.
Description
Colony encrusting. Autozooids polygonal (c.0.9×0.45 mm);
frontal shields convex, uniformly perforate; marginal pores and
lateral walls distinct. Primary orifice longer than wide, the anter
with a shelf-like ledge of calcification which acts as condyles
proximally, terminating distal to a small pair of lateral denticles
and a narrow, triangular median denticle. Four oral spines.
Mucro small, dominated by the large associated avicularium;
cystid inflated, occupying almost half of the frontal shield;
rostrum elongate, rounded, narrowed centrally, minutely ser-
rated distally; mandible almost spatulate; crossbar complete,
with a large columella. Smaller, single or paired lateral oral
avicularia often present; oval, laterally directed, but may be
replaced by a large avicularium similar to that of the suboral
mucro. Ovicell not observed. Large, vaulted, distal radicular
chamber with uniporous septular pores, remainder of basal
wall perforated by large uniporous septular pores.
Remarks
Mucropetraliella tuberosa is characterised by its narrow, tri-
angular median denticle and its four oral spines, but more
particularly by its very large suboral avicularium with a very
large columella. It has a distinct pattern of basal pores (cf. Pet -
raliella magna), the entire basal surface being covered with
uniporous septular pores, those distal most recessed and pro-
ducing rhizoids (Fig. 10D). The suboral avicularium differs
in size from one autozooid to another but all are still far lar-
ger than those seen in both M. bennetti and M. serrata. With
the exception of M. vultur from South Australia (which has
six oral spines), these avicularia are the largest seen in any
species of Mucropetraliella without a large suboral mucro.
Species such as M. neozelanica and M. thenardii (Audouin,
1826) (Figs 11A, B) have larger suboral avicularia but these
are associated with a large suboral mucro. M. thenardii pro-
duces an extremely elaborate suboral mucro which, as well as
an extremely large associated avicularium, produces further
spinous processes that often bear small avicularia themselves
(Fig. 11B).
Mucropetraliella tuberosa does not have any other avicu-
laria on the frontal shield, unlike both M. bennetti and M.
serrata. It does however, have four oral spines like M. mag-
nifica, M. neozelanica,M.capricornensis and M. loculifera.
M. loculifera can easily be distinguished from the rest of these
species by the presence of occlusor-laminae within the primary
orifice. As previously mentioned, M. neozelanica (Figs 11C,
D) has a large suboral mucro with an associated avicularium
that is often large. One character, however, which distinguishes
M. neozelanica from the other species of Mucropetraliella
which bear four oral spines, is the presence of very elong-
ate lateral oral avicularia, which, either single or paired, are
always directed distally (Fig. 11D). Mucropetraliella magni-
fica (Figs 11E, F) on the other hand has little in the way of
a suboral mucro with a small associated avicularium. It does
have larger elongate avicularia; either lateral-oral and directed
disto-laterally, or frontally and directed perpendicularly to the
marginal walls (Fig. 11F). The recently described M. capri-
cornensis has a small mucro and associated avicularium. The
peri-oral and frontal avicularia are similar in size to the suboral
avicularia. The most characteristic feature of M. capricornen-
sis is the positioning of the oral spines; they are positioned in
closely associated pairs, with each of the two pairs at one of the
two disto-lateral ‘corners’ of the rather subrectangular primary
orifice.

Petraliellid bryozoans from Queensland 335
Figure 10 A–D, Mucropetraliella tuberosa (Busk, 1884). A, C, BMNH 2001.4.11.1, East Australian coast. B, D, Holotype BMNH 1887.12.9.566,
Port Jackson, New South Wales. A, primary orifice, note the shelf-like ledge around the inner edge of the anter, which terminates
distal to the lateral denticles. B, group of zooids, note the ovicellate zooid (centre) and the suboral mucros and enlarged suboral
avicularia of the surrounding autozooids. C, cleaned basal surface of several zooids, note the numerous uniporous septular pores
and vaulted, distal radicular chamber of uniporous septular pores. D, uncleaned basal surface, note the thin membranous covering,
and rhizoids emerging from the position of the radicular chambers. A, scale bar 100 µm; B, scale bar 400 µm; C, D, scale bar 500 µm.
Harmer (1957: 693) proposed the taxon Poripetraliella,
a new subgenus of Mucropetraliella, with Busk’s (1884) Lep-
ralia tuberosa as the type species. Nowhere does Harmer
(1957) qualify this erection or differentiate Poripetrali-
ella from Mucropetraliella (Mucropetraliella) [by inference]
sensu stricto. Therefore Poripetraliella as a valid taxon is
rejected.
The East Australian specimen described here as Mucro-
petraliella tuberosa originally had the same registration num-
ber as that of a specimen of Petraliella concinna (BMNH
1866.6.22.10), however, this specimen has remained unidenti-
fied until now. F. M. Raymer Esq., formerly of H.M.S. Herald,
presented the specimens as part of a collection of ‘Zoophytes’
to the Natural History Museum, London.
Mucropetraliella tuberosa has only been recorded once
previously, from New South Wales, and its occurrence off the
Queensland coast extends the known range of this distinctive
species.
Genus Sinupetraliella Stach, 1936
Sinupetraliella Stach, 1936: 378.
Sinupetraliella: Harmer, 1957: 705.
TYPE SPECIES: Petralia litoralis Hastings, 1932.
Diagnosis
Orifice with lateral denticles forming an asymmetric sinus
in the proximal margin. Proximal mucro (which may look
flattened) with an associated suboral avicularium always
present. Spines absent.
Remarks
The asymmetry of the proximal sinus varies considerably
from species to species, and some, such as Mucropetraliella
asymmetrica Hayward & Cook (1983), from South Africa,
could perhaps be equally well accommodated in Sinupetrali-
ella. Harmer (1957) regarded the lateral denticles as condyles,

336 K. J. Tilbrook & P. L. Cook
Figure 11 A, B, Mucropetraliella thenardii (Audouin, 1826), BMNH 1963.9.8.93, Sri Lanka. A, primary orifice of uncleaned specimen, note the
small median denticle, lateral sinuses and denticles above the in situ operculum. B, group of zooids, note the globular ovicells and
the extremely elaborate suboral mucro of some zooids. C, D, Mucropetraliella neozelanica (Livingstone, 1929), BMNH 1964.8.12.16H,
Three Kings Islands, New Zealand. C, primary orifice, note the anvil-shaped median denticle, triangular lateral denticles, and
shelf-like ledge around the inner edge of the anter. D, group of autozooids, note the inflated suboral mucros of some zooids and
distally directed, lateral oral avicularia of others. E, F, Mucropetraliella magnifica (Busk, 1884), BMNH 1944.1.8.308, Honolulu,
Hawai’i. E, primary orifice, note the small median denticle and lateral denticles, suboral avicularium, and shelf-like ledge around the
inner edge of the anter. F, group of zooids, including two ovicellate zooids, note the variable size of the distolaterally directed,
lateral oral avicularia. A, E, scale bar 100 µm; B, D, scale bar 400 µm; C, scale bar 50 µm; F, scale bar 500 µm.

Petraliellid bryozoans from Queensland 337
although they have no articulatory function (see Introduction
above).
Sinupetraliella litoralis (Hastings, 1932)
Figs 12A–C
Petralia litoralis Hastings, 1932: 438, pl. 1, fig. A;
text fig. 15.
Petraliella litoralis: Ryland, 1974: 342.
Sinupetraliella litoralis: Stach, 1936: 378; Harmer, 1957
(in part): 706; Ryland & Hayward, 1992: 276, fig. 25a;
Tilbrook, Hayward & Gordon, 2001: 86, fig. 19A.
Material examined
HOLOTYPE: BMNH 1932.4.20.61, Low Island, off Port
Douglas, Queensland, between tidemarks.
PARATYPES: BMNH 1932.4.20.60,62; AM U.2729, (locality
as above).
OTHER MATERIAL EXAMINED: BMNH 1993.7.26.63–
67, Heron Island, Great Barrier Reef, 13.04.72; BMNH
1996.2.23.5,99,124, Heron Island, Great Barrier Reef; BMNH
1999.4.11.1,8, Green Island, Great Barrier Reef; BMNH
2000.4.11.7,10,11, Green Island, Great Barrier Reef, 08.07.72;
BMNH 2000.4.11.12, Heron Island, Great Barrier Reef;
BMNH 1998.8.4.26, Port Vila Harbour, Efate, Vanuatu.
Description
Colonies brown in life, loosely encrusting. Autozooids poly-
gonal (c.0.95×0.80 mm); frontal shield uniformly perfor-
ated by large pores; marginal pores and lateral walls distinct.
Primary orifice orbicular, with a deep proximal sinus asym-
metrically placed, flanked by two lateral denticles. Suborally a
small median mucro bears a small, rounded avicularium, facing
over the orificial sinus; mandible rounded and hooked termin-
ally. Other small, elongate triangular, sutural avicularia occur;
rostrum raised from the frontal shield, variously orientated;
mandibles acute. Ovicells prominent, finely tuberculate, with
finger-like bars of marginal secondary calcification forming a
radial pattern. Basal radicular chambers distal, very small.
Remarks
Sinupetraliella litoralis is characterised by its asymmetrical
sinus, small mucronal avicularium, triangular sutural avicu-
laria and ovicell surrounded by finger-like bars of secondary
calcification.
The paratype fragments of S. litoralis, although dried,
show traces of several rhizoids, 5–6mm long, emanating from
the very small radicular chambers. Harmer (1957) figured
(pl. 45, figs 11–13) very large lateral oral avicularia in his speci-
mens from South Celebes. Their absence from the Queensland
material suggests that his East Indian material is not S.litoralis
sensu stricto, but belongs to a distinct species.
Sinupetraliella litoralis sensu stricto has only been re-
corded from the Great Barrier Reef and Vanuatu but it is likely
to be found elsewhere in the Coral Sea.
Figure 12 A–C, Sinupetraliella litoralis (Hastings, 1932), Holotype
BMNH 1932.4.20.61, Low Island, Queensland. A, primary
orifice, note the asymmetrically positioned proximal
sinus, the triangular lateral denticles, and the suboral
avicularium with its serrated mandible. B, groups of
autozooids. C, groups of ovicellate zooids showing the
characteristic calcification finger-like bars of marginal
secondary calcification over the ovicell. A, scale bar
100 µm; B, scale bar 1000 µm; C, scale bar
500 µm.

338 K. J. Tilbrook & P. L. Cook
Discussion
Ten species of petraliellids, belonging to three genera, are de-
scribed from Queensland. Two species, Petraliella buski and
P. magna, are stabilised by the nomination of lectotype spe-
cimens. P. magna is also described to avoid further confu-
sion about its identity. It appears that the Indo-Pacific, and
the regions around Australia in particular, contain the highest
diversity of petraliellids. Only eight Recent petraliellid spe-
cies have been described from Atlantic and Caribbean waters.
A preliminary study shows that whilst the species assigned
to Petraliella appear quite widespread in their distribution
(P. concinna being a possible exception), the more speciose
genera of Mucropetraliella and Sinupetraliella appear to be
more geographically limited. In particular, many species of
Sinupetraliella occur in the region of Indonesia, Malaysia
and the Philippines whereas many species of Mucropetrali-
ella occur around Victoria and southern Australia in general.
A comprehensive description of each genus would require the
comparison of type material with specimens from all known
populations to give the correct distribution of the species in-
volved.
Acknowledgements
The authors would like to thank: the Department of Zoology,
The Natural History Museum, London, for access to their col-
lections and for the provision of bench space to KJT; Dr Penny
Berents (Australian Museum, Sydney Australia) and Prof.
Agn´
es Rage (Museum National d’Histoire Naturelle, Paris,
France) for the loan of type material; Ms Mary Spencer Jones
for her help and patience; and Dr Phil Bock for comments on
previous drafts of this manuscript.
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