Hybanthopsis, a new genus of Violaceae from Eastern Brazil

Abstract

A new genus of Violaceae is described from Brazil.Hybanthopsis Paula-Souza, with a single species (H. bahiensis Paula-Souza), is endemic to caatingas of Bahia, Brazil, and is morphologically most similar toHybanthus, from which it differs by the fruit morphology and especially its peculiar seeds.
Um novo gênero brasileiro de Violaceae é descrito.Hybanthopsis Paula-Souza, com uma única espécie (H. bahiensis Paula-Souza), é endêmico de caatingas do Estado da Bahia, e é morfologicamente mais similar aHybanthus, do qual difere pela morfologia do fruto e especialmente por suas sementes peculiares.

Full text

Brittonia, 55(3), 2003, pp. 209–213. ISSUED: 17 July 2003
q
2003, by The New York Botanical Garden Press, Bronx, NY 10458-5126 U.S.A.
Hybanthopsis, a new genus of Violaceae from
Eastern Brazil
J
ULIANA DE
P
AULA
-S
OUZA AND
V
INICIUS
C
ASTRO
S
OUZA
Paula-Souza, J. & V. C. Souza. (Herbarium ESA, Universidade de Sa˜o Paulo/
ESALQ, Av. Pa´dua Dias 11, C.P. 09, Piracicaba, Sa˜o Paulo, 13418-900, Brazil;
email: jupsouza@esalq.usp.br). Hybanthopsis, a new genus of Violaceae from
Eastern Brazil. Brittonia 55: 209–213. 2003.—A new genus of Violaceae is de-
scribed from Brazil. Hybanthopsis Paula-Souza, with a single species (H. bah-
iensis Paula-Souza), is endemic to caatingas of Bahia, Brazil, and is morpholog-
ically most similar to Hybanthus, from which it differs by the fruit morphology
and especially its peculiar seeds.
Key words: Bahia, Brazil, Caatinga, Hybanthus,Hybanthopsis, systematics,
Violaceae.
Paula-Souza, J. & V. C. Souza. (Herbarium ESA, Universidade de Sa˜o Paulo/
ESALQ, Av. Pa´dua Dias 11, C.P. 09, Piracicaba, Sa˜o Paulo, 13418-900, Brasil;
email: jupsouza@esalq.usp.br). Hybanthopsis, a new genus of Violaceae from
Eastern Brazil. Brittonia 55: 209–213. 2003.—Um novo geˆnero brasileiro de Vio-
laceae e´ descrito. Hybanthopsis Paula-Souza, com uma u´nica espe´cie (H. ba-
hiensis Paula-Souza), e´ endeˆmico de caatingas do Estado da Bahia, e e´ morfo-
logicamente mais similar a Hybanthus, do qual difere pela morfologia do fruto e
especialmente por suas sementes peculiares.
Introduction
The family Violaceae is cosmopolitan
and comprises ca. 25 genera and 850 spe-
cies; approximately 70 of the species are
found in Brazil. The largest genus, Viola,is
widely distributed in temperate zones but
also occurs in higher altitudes in warmer
regions. In the tropics and subtropics, the
most representative genera of the family are
the mainly woody Rinorea and Hybanthus;
and these genera show great diversity, es-
pecially in the Neotropics. Saint-Hilaire
(1824) produced the first major treatment of
the Brazilian Violaceae. Although the au-
thor focused only on the extra-Amazonian
region, he described several Hybanthus spe-
cies and four species of Brazilian Viola.
The only complete taxonomic study of the
Brazilian plants was produced by Eichler
(1871) in Flora Brasiliensis, in which 48
species were treated. Brazilian species were
treated by Schulze’s (1936) study of neotro-
pical species of Hybanthus and Hekking’s
(1988) monograph of Rinorea and Rinoreo-
carpus for Flora Neotropica Monographs.
Recent taxonomic studies have been re-
stricted to local areas or floras and many of
the genera are usually overlooked and given
little attention, and thus this family is still
very poorly known for Brazil.
According to Hekking’s (1988) recent
classification of the family, which was
based mainly on the symmetry of the flow-
ers, aestivation of petals and petal and an-
ther morphology, most genera belong to the
Rinoreeae and Violeae. Recent studies
based on rbcL sequences, indicate, howev-
er, that these tribes are not monophyletic
(Judd et al., 1999).
In the course of preparing an account of
the Brazilian species of Hybanthus (Souza,
2002), some interesting specimens from
Bahia that showed the same floral structure
as Hybanthus, but different seed morphol-

210 [VOL. 55
BRITTONIA
ogy, were thought to be a new twining spe-
cies of the genus. The seeds of Hybanthus
are always ovoidal-ellipsoidal, but those of
the twining specimens from Bahia are com-
pletely different (Figs. 2A–D), unique in
shape among the Neotropical Violaceae.
The fruits of the plants from Bahia are thin
walled and chartaceous, very distinct from
the coriaceous capsule in Hybanthus. These
plants are described here as a new genus,
Hybanthopsis.
Although most species of Hybanthus are
herbs, (sub-) shrubs, or less frequently tree-
lets, Hybanthus volubilis E. M. Bennett, of
western Australia (Bennett, 1972) is the
only species with a twining habit. The
widespread extra-Amazonian Anchietea and
the Amazonian Corynostylis are Neotropi-
cal lianescent Violaceae, but their floral
morphology is distinct: their flowers have
the anterior petal long-spurred with the nec-
tariferous appendages being the same
length and included in the spur of the petal.
Like Hybanthus and Hybanthopsis, the
South Pacific lianescent genus Agatea has
a saccate flower and might be closely allied
to the new genus. The chartaceous capsule
and semi-obsolete ridge on the seeds of
Hybanthopsis suggest a closer relationship
with Anchietea despite the absence of a
well-developed spur.
Material and Methods
This study is based on field observations
of living specimens and material from the
following herbaria: ALCB, ASE, BHCB,
BM, BR, CEN, CEPEC, CESJ, CPAP,
CVRD, EAC, EAN, ESA, FCAB, FUEL,
G, GFJP, GUA, HB, HBR, HEPH, HRB,
HRCB, HUCS, HUEFS, HUFU, HURG,
IAC, IAN, IBGE, IPA, JPB, K, LINN, M,
MAC, MBM, MBML, MG, P, PACA, PEL,
R, RB, SJRP, SMDB, SP, SPF, SPSF, UB,
UEC, UFG, UFP, UPCB, and VIC.
SEM images were made using material
removed from herbaria specimens. Seeds
were coated with a thin layer of gold and
then examined in a LEO 435 VP scanning
electron microscope, at the Nu´cleo de
Apoio a` Pesquisa/Microscopia Eletroˆnica
Aplicada a` Pesquisa Agropecua´ria (NAP/
MEPA—ESALQ/USP).
Taxonomy
Hybanthopsis Paula-Souza, gen. nov.
T
YPE
:H. bahiensis Paula-Souza.
Structura florali Hybanthus Jacq. affinis, sed habitu
volubili et seminibus aspectu dorsali obovatis, ad ba-
sem expansionibus duabus lateralilbus multo differt.
Twining herbs. Leaves serrate, the teeth
glandular, stipules 2. Flowers solitary, ax-
illary, sepals 5, free; corolla strongly zy-
gomorphic, petals 5, free, the anterior petal
clawed, concave or saccate at base; stamens
5, membranous connective appendages at
apex of anthers; carpels 3. Capsule thin-
walled, chartaceous, opening by a single
longitudinal slit; seeds obovate in dorsal
view with two lateral expansions at the
base.
Hybanthopsis bahiensis Paula-Souza, sp.
nov. Figs. 1 & 2
T
YPE
:B
RAZIL
: Bahia. Itatim, Morro das
Tocas, 310–430 m, 12
8
43
9
S, 39
8
42
9
W, 27
Jan 1996 (fl, fr), F. Franc¸a et al. 1507 (
HO
-
LOTYPE
: ESA,
ISOTYPE
: HUEFS).
Rami pubescentes, tomentosi vel hirsuti, juniores
saepe vinosi. Folia alterna, petiolata, membranacea,
ovata vel lanceolata, apice acuto vel acuminato, base
cordata, pubescenti, tomentosa vel hirsuta. Flores li-
lacini vel purpurascentes; bracteolae nullae; antherae
appendicibus connectivi aurantiaco-brunneis; appen-
dices nectariferae filamentorum duorum anticorum no-
duliformes vel conicae; ovarium glabrum. Semina pu-
bescentia, pagina dorsali foveolata.
Twining herb; stems terete, pubescent,
tomentose or hirsute, frequently vinaceous
when young. Leaves alternate, membra-
nous, internodes 1.6–4.5(–8) cm long;
stipules 3.5–5
3
1 mm, lanceolate, entire,
reddish to vinaceous; petiole 5.5–11 mm
long; lamina 3.8–6.1
3
1.6–4.2 cm, ovate
or lanceolate, apex acute to acuminate,
margin serrate, base cordate, pubescent, to-
mentose, or hirsute, hairs simple. Flowers
lilac or purplish, sometimes with darker
linear markings, solitary, axillary, pedicel
(0.6–)2–3 cm long, articulate, tomentose to
hirsute; bracteoles absent. Sepals equal,
3.5–4.5
3
ca. 1 mm, lanceolate, apex acu-
minate, entire, base truncate, pubescent to
tomentose. Upper petals 3–4
3
1.5 mm,

2003] 211
SOUZA & SOUZA: VIOLACEAE
F
IG
.1. Hybanthopsis bahiensis.A. Habit; B–E. Seed: B. Dorsal view, C. Lateral view, D. Ventral view, E.
Frontal view; F. Gynoecium, androecium and floral pedicel; G. Calyx; H. Posterior stamen; I. Anterior stamen;
J. Gynoecium; K. Corolla. (From Franc¸a et al. 1507, Holotype ESA.)
oblong to elliptic, apex obtuse to rounded;
lateral petals 5.5–7.5
3
2–3.5 mm, oblong
to spatulate, falcate, apex obtuse to round-
ed; anterior petal 11–16 mm long, the lam-
ina suborbicular to flabelliform. Staminal
filaments ca. 0.5–1 mm long; anthers ca.
1.5 mm long, the connective appendages
orange-brown, acute, sometimes asymmet-
ric, about as long as the anthers, both an-
terior staminal filaments with noduliform
or (sub-)conical nectary appendages,
sometimes one or both of the anterior sta-

212 [VOL. 55
BRITTONIA
F
IG
. 2. Scanning electron micrographs. A–E.Hybanthopsis bahiensis.A–D. Seed: A. Dorsal view; B. Lateral
view; C. Ventral view; D. Detail of testa. E. Glandular tooth of leaf. (From Noblick 3615, ESA.) F.Hybanthus
calceolaria (L.) Oken. Seed. (From Oliveira 20, HUEFS.)
mens fused with the adjacent posterior sta-
mens by their filaments. Ovary 1.5–2 mm
long, glabrous, style 2 mm long, straight
or slightly curved. Capsule 1.7–2.1 cm
long, 0.8–1.4 cm diam., ellipsoid, charta-
ceous; seeds 4.5–5 mm long, 3 mm wide,
pubescent, the dorsal surface foveolate.
Distribution and ecology. Hybanthopsis
bahiensis is endemic to arid, deciduous for-
ests (caatingas) of central-eastern Bahia (ca.
12
8
–14
8
S) and is commonly found in dis-
turbed areas such as forest borders and
roadsides.
According to Hekking’s (1988) classifi-
cation, the floral characteristics of Hybant-
hopsis place it in the Violeae of the Vio-
loideae.
The genera most similar to Hybanthopsis
in the Violeae can be distinguished by the
following key:
Key to some related Neotropical genera
of Violeae
1. Anterior petal saccate or slighty dilated; an-
terior stamens with short spurred, gib-
bose or noduliform nectariferous append-
ages.
2. Erect herbs, (sub-) shrubs, or treelets;
capsules thick-walled, coriaceus,
opening by 3 longitudinal slits; seeds
glabrous, ovoid-ellipsoid with no ex-
pansions at the base (widespread).
--------------------------------------------------------
Hybanthus
2. Twining herbs; capsule thin-walled,
chartaceous, opening by a single
longitudinal slit; seeds pubescent, in
dorsal view obovate with two lateral
expansions at the base (Bahia, Bra-
zil).
------------------------------------------
Hybanthopsis
1. Anterior petal long-spurred; anterior sta-
mens with long nectariferous appendages
that are included in the petal spur.
3. Fruit a membranous swollen capsule

2003] 213
SOUZA & SOUZA: VIOLACEAE
(extra-Amazonian South America).
---------------------------------------------------------
Anchietea
3. Fruit a coriaceus capsule (Amazonia
and Mesoamerica).
------------------
Corynostylis
The name Hybanthopsis refers to the ge-
nus’ resemblance to the genus Hybanthus.
Additional specimens examined: BRAZIL: Bahia:
Cravolaˆndia, 31 Jan 1991 (fl), Melo & Franc¸a 461
(CEN); Feira de Santana, Serra de Sa˜o Jose´, 08 Jul
1982 (fl), Arouck et al. 176 (HRB, RB); Mata de Sa˜o
Jose´, 08 Jul 1982 (fl), Guedes 528 (ALCB); 12
8
15
9
S,
38
8
58
9
W, 08 Jul 1982 (fl), Brito 01 (ALCB, ESA,
HUEFS); Iac¸u, Morro da Garrafa, 250 m, 12
8
45
9
18
0
S,
39
8
51
9
W, 23 Feb 1997 (fl, fr), Melo 2113 (ESA,
HUEFS); road between Iac¸u and Milagres, Fazenda
Santo Antoˆnio, 12
8
48
9
S, 40
8
05
9
W, 300 m, 20 Jul 2001
(fl), J. P. Souza et al 3586 (ESA); Fazenda Suibra (Boa
Sorte), 18 km E from Iac¸u following the railway,
12
8
43
9
S, 40
8
7
9
W, 13 Mar 1985 (fl, fr), Noblick 3615
(CEPEC, ESA, HUEFS); Itaberaba, BR 242, 25 km E
from the city, 12
8
31
9
S, 40
8
17
9
W, 22 Apr 1984 (fl, fr),
Noblick et al. 3138 (CEPEC, ESA, HUEFS); Itatim,
road to Lajedo Alto, ca. 1 km from BR 116,
12
8
45
9
47,1
0
S, 39
8
49
9
06,3
0
W, 29 Jul 2001 (buds, fr), J.
P. Souza et al. 3589 (ESA, ALCB, BHCB, CEPEC,
G, HUEFS, K, M, MBM, NY, P, RB, SP, SPF); Jequie´,
May 1954 (fl), Vidal IV-1011 & IV-1027 (R); Santa
Teresinha, 6 km NE from Santa Teresinha, on the road
between Santa Teresinha and Monte Cruzeiro, 400 m,
12
8
48
9
56
0
S, 39
8
32
9
05
0
W, 27 May 1987 (fl, fr), Queiroz
et al. 1553 (ALCB, CEPEC, ESA, HUEFS, RB, HRB).
Acknowledgments
The authors are grateful to the Fundac¸a˜o
de Amparo a` Pesquisa do Estado de Sa˜o
Paulo (FAPESP) for financial support (Pro-
cess 99/07101-8) and to the curators of the
herbaria who sent specimens for study. We
also want to thank Roge´rio Lupo for pre-
paring the illustration and Elliot Watanabe
Kitajima and Maria das Grac¸as Ongarelli
from the Nu´cleo de Apoio a` Pesquisa/Mi-
croscopia Eletroˆnica Aplicada a` Pesquisa
Agropecua´ria (NAP/MEPA—ESALQ/USP)
for making the equipment available and for
help in taking the SEM images.
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