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Neighbor-joining tree of fossil species (in red) and extant species. Bootstrapping values are shown on the node. The tree was rooted using Franklandia, Eidothea, Faurea, and Protea as outgroup.
Source publication
New Caledonia and New Zealand belong to the now largely-submerged continent, Zealandia. Their high levels of endemism and species richness are usually considered the result of transoceanic dispersal events followed by diversification after they re-emerged from the Pacific Ocean in the mid-Cenozoic. Here, we explore the origin and evolutionary histo...
Contexts in source publication
Context 1
... more widely (Table 1) Our phenetic analysis of 11 pollen characters for eight extant Beauprea species and four fossil species with Beauprea-type pollen showed close relationships among all Beauprea, Beaupreaidites, and Peninsulapollis species, but not with other extant genera in the same subfamily such as Protea, Faurea, Franklandia, and Eidothea (Fig. 3). Beaupreaidites is clearly embedded among Beauprea, whereas Peninsulapollis is also well within Beauprea. Maximum likelihood analysis indicated that B. orbiculatus and Beauprea montisfontium have very similar pollen, followed by Beauprea balansae, as Dettermann and Jarzen (33) suggested (Fig. 3). The eight extant Beauprea species and ...
Context 2
... such as Protea, Faurea, Franklandia, and Eidothea (Fig. 3). Beaupreaidites is clearly embedded among Beauprea, whereas Peninsulapollis is also well within Beauprea. Maximum likelihood analysis indicated that B. orbiculatus and Beauprea montisfontium have very similar pollen, followed by Beauprea balansae, as Dettermann and Jarzen (33) suggested (Fig. 3). The eight extant Beauprea species and four Beauprea-type fossil species were clustered into two groups. All four fossil species and five extant species formed a group, whereas Beauprea asplenioides and another two extant species formed another group (Fig. 3). Cranwellipollis pollen was grouped with Franklandia (both having almost ...
Context 3
... similar pollen, followed by Beauprea balansae, as Dettermann and Jarzen (33) suggested (Fig. 3). The eight extant Beauprea species and four Beauprea-type fossil species were clustered into two groups. All four fossil species and five extant species formed a group, whereas Beauprea asplenioides and another two extant species formed another group (Fig. 3). Cranwellipollis pollen was grouped with Franklandia (both having almost identical ...
Context 4
... were grouped with the lineage containing B. montisfontium and B. spathulifolia, which have a pollen structure similar to that of B. orbiculatus and B. elegansiformis, respectively. Beaupreaidites diversiformis and P. gillii were positioned at 80.6 Ma, and the two species share a similar pollen structure, as revealed by the neighbor-joining tree (Fig. 3). Because the actual age of B. orbiculatus (83.5 Ma) exceeded the median crown age, as estimated from MCMC (82.5 Ma), the age of the lineage was pulled back to 83.5 Ma, which was still within the 95% HPD of the MCMC age estimate of the lineage (Fig. 4). In the supertree incorporating known fossil and extant species of Beauprea (Fig. 4), ...
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Fire stimulates germination of most seeds in fire-prone vegetation. Fruits of Leucadendron (Proteaceae) are winged achenes or nutlets that correlate with their requirements for smoke and/or heat in promoting germination. We describe five possible smoke–heat dormancy-release/germination syndromes among plants, of which Leucadendron displays three (n...
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Citations
... That work was expanded here to cover the entire family. The areocladogram results of Sauquet et al. (2009) for the Proteaceae have been shown to produce inapplicable migratory pathways (He, Lamont and Fogliani, 2016;Lamont et al., 2023). Together with the limited success in linking palynomorphs to particular Proteaceae clades in the past (Sauquet et al., 2009;Lamont et al., 2023), the areocladogram approach was not adopted here. ...
... On this point, there may be significance in their record of Tricolpites sp in the Albian?-Cenomanian (112-93.6 Ma) (Vallati, 2006) that has the diagnostic features of Peninsulapollis gillii (earlier classified as Tricolpites gillii) which they recorded later at the same site (Vallati et al., 2016). If our identification is confirmed it means that the origin of Beauprea would need to be changed from Antarctica to S South America and its age increased by at least 5 My to 94 Ma (He, Lamont and Fogliani, 2016). This then becomes another example of a (Proteaceae) clade arising in South America and proceeding south rather than the reverse, as previously thought for Beauprea. ...
... An exhaustive search for fossil records of the Proteaceae in Africa was undertaken and the dates and location of the records were made and information on the postulated climate, fireproneness (charcoal) and vegetation and other environmental factors at those times was noted. A Proteaceae affinity of the palynomorphs was based on assignments made by palynologists (Boltenhagen, 1978;Scholtz, 1985;Dettmann and Jarzen, 1996;Sauquet and Cantrill, 2007;Sauquet et al., 2009;Cantrill et al., 2013;He et al., 2016;Warny et al., 2019), the advice of a Proteaceae fossil-pollen expert (Lynne Milne) and occasional comparisons of our own (see Supplementary Data Table S3 and Appendix for details on our assessments of some key assignments). Fossil age ranges were calculated from their associated sedimentary strata as in He et al. (2016) and the dates recorded for the oldest record of a given fossil type, including a new record for Triorites africaensis at 107-94 million years ago (Ma), were used for calibrating the chronogram. ...
... A Proteaceae affinity of the palynomorphs was based on assignments made by palynologists (Boltenhagen, 1978;Scholtz, 1985;Dettmann and Jarzen, 1996;Sauquet and Cantrill, 2007;Sauquet et al., 2009;Cantrill et al., 2013;He et al., 2016;Warny et al., 2019), the advice of a Proteaceae fossil-pollen expert (Lynne Milne) and occasional comparisons of our own (see Supplementary Data Table S3 and Appendix for details on our assessments of some key assignments). Fossil age ranges were calculated from their associated sedimentary strata as in He et al. (2016) and the dates recorded for the oldest record of a given fossil type, including a new record for Triorites africaensis at 107-94 million years ago (Ma), were used for calibrating the chronogram. Note that we accept the convention in palaeontology to give the older date in a range first followed by the younger. ...
... We therefore set the crown age of the Proteaceae family at 101 Ma [mean of 107-94 Ma, and a standard deviation of 10 million years (My)]. As no other fossils could be precisely identified to have affiliations with any sampled genera, a secondary calibration point was extracted from He et al. (2016) with the crown age of the common ancestor of Franklandia at 81.4 Ma with a standard deviation of 8.1 My. The crown age of the most-recent common ancestor of Proteales was set at 125 Ma with a standard deviation of 12.5 My (Magallón et al., 1999;Mast et al., 2012). ...
Background and aims:
The prevailing view from the areocladogenesis of molecular phylogenies is that the iconic South African Cape Proteaceae (subfamily Proteoideae) arrived from Australia across the Indian Ocean in the Upper Cretaceous (100‒65 million years ago, Ma). Since fossil pollen indicates that the family probably arose in North-West Africa during the early Cretaceous, an alternative view is that it migrated to the Cape from North-Central Africa. The plan therefore was to collate fossil pollen records throughout Africa to determine if they are consistent with an African (para-autochthonous) origin for the Cape Proteaceae, and to seek further support from other paleo-disciplines.
Methods:
Palynology (identity, date and location of records), molecular phylogeny and chronogram preparation, biogeography of plate tectonics, and paleo-atmospheric and ocean circulation models.
Key results:
Our collation of the rich assemblage of Proteaceae palynomorphs stretching back to 107 Ma (Triorites africaensis) in North-West Africa showed its progressive overland migration to the Cape by 75‒65 Ma. No key palynomorphs recorded in Australia-Antarctica have morphological affinities with African fossils but specific clade assignment of the preMiocene records is not currently possible. The Cape Proteaceae encompass three molecular-based clades (tribes) whose most-recent apparent ancestors are sisters to those in Australia. However, our chronogram shows that the major Adenanthos/Leucadendron-related clade, originating 54‒34 Ma, would have 'arrived' too late as species with Proteaceae affinities were already present ~20 My earlier. The Franklandia/Protea-related clade arose 118‒81 Ma so its distinctive pollen should have been the foundation for the scores of palynomorphs recorded at 100‒80 Ma but it was not. Also, the prevailing winds and ocean currents trended away from South Africa rather than towards, as the 'out-of-Australia' hypothesis requires. Based on the evidence assembled here, we list three points favouring an Australian origin and nine against; four points favouring an Antarctic origin and seven against; and nine points favouring a North-Central African origin and three against.
Conclusions:
We conclude that a gradual migration of the Proteaceae from North-Central Africa southeast→south→southwest to the Cape and surrounds occurred via adaptation and speciation during the period 90‒70 Ma. We caution that incorrect conclusions may be drawn from literal interpretations of molecular phylogenies that neglect the fossil record and do not recognize the possible confounding effects of selection under matched environments leading to parallel evolution and extinction of bona fide sister clades.
... In particular, there is no guarantee that this is the time it separated from its sister lineage and it is sure to have been earlier, sometimes much earlier. Further, correct identification of pollen to genus level is difficult (partly because they are rarely located with the parent plant) and even numerical taxonomic analyses can come up with different answers (e.g., see Sauquet et al. 2009 andHe et al. 2016 for differences over the correct identity of Beaupreaidites orbiculatus, a key palynomorph in the origin of Beauprea). Bell et al. (2010) set the split of Dipterocarpoid Dipterocarpaceae from its sister, Sarcolaenaceae, at 38 Ma. ...
... We incorporated fossil evidence of its historical presence on a given plate without paying particular attention to its age as areogram techniques only have a spatial, not temporal, component. This approach mirrors that adopted by He et al. (2016) who demonstrated an autochthonous origin for Beauprea in New Caledonia. Thus, we asked: did the Dipterocarpaceae sl and its daughter clades originate in Gondwana before the tectonic plates that they currently occupy begin to separate? ...
... Seeds have a prominent, lychee-like aril attractive to vertebrate disperserscurrently lemurs and birds (Horn 2004). There is a distribution mismatch between frugivorous birds that consume seeds adapted for endozoochory in forests and omnivorous seabirds on the coast that might rarely be caught up by hurricanes to spread seeds to other lands (He et al. 2016). Thus, we can dismiss birds/ pterosaurs as possible transoceanic dispersal agents. ...
There is disparity between the estimated time of origin
of the ‘superclade’ Dipterocarpaceae sensu lato, that
includes Sarcolaenaceae, Cistaceae, Pakaraimaea, Bixaceae,
Cochlospermaceae and Sphaerosepalaceae, as determined by
recent molecular phylogenies (100−85 million years ago, Ma) and
its strongly tropical, South American-African-Madagascan-SE Asian
distribution that indicates an older Gondwanan origin (>110 Ma).
We used several paleobiogeographic approaches, including
recently reported fossil records, to explore the hypothesis that
Dipterocarpaceae sl has a Gondwanan/early-Cretaceous origin.
We created molecular phylogenies for this group, assigned
each genus/family to the tectonic plate on which it is extant, and
subjected the cladogram to areogram analysis. We also assessed
ecological, mycotrophic and morphological traits, and global
circulation patterns, as these might affect this group’s distribution.
The initial analysis (omitting fossil evidence) showed that the
crown of Dipterocarpaceae sl occurred concurrently on the South
American and Madagascan plates. Including fossils from Africa and
India changed this to a South American-African origin. Collectively,
these origins represent NorthWest Gondwana with South America,
Africa and Madagascar remaining conjoined until ≥105–115 Ma,
setting the minimum age for this superclade with some evidence
that it may be much older. We also show that the immediate
ancestors of the three daughter lineages [Dipterocarpaceae-
Sarcolaenaceae (in Africa/Madagascar, ≥115 Ma), Cistaceae-
Pakaraimaea (South America/Africa/Eurasia, ≥105 Ma) and
Bixaceae-Cochlospermum-Sphaerosepalaceae (South America/
Africa, ≥105 Ma)] also arose in NorthWest Gondwana.
The immediate ancestors or basal species in Sarcolaenaceae,
Sphaerosepalaceae, Dipterocarpaceae (both its subfamilies) and
Bixaceae migrated from (South America)/Africa to Madagascar
and we propose that the Dipterocarpoideae proceeded from
Africa to India while still linked to Madagascar. In addition, much
subsequent diversification of this superclade has occurred on the
Eurasian, Indian, SE Asian (Sunda) and North American plates
post-Gondwanan breakup.
This long vicariant history is supported by fossil, ecological,
mycotrophic and morphological traits, and global circulation
patterns that show negligible propensity for transoceanic dispersal
to explain this clade’s wide intercontinental distribution.
We conclude that all these areocladogram/plate-breakup/
ecomorphological/circulation features are consistent with
a Gondwanan/early-Cretaceous (>115 Ma) origin for the
Dipterocarpaceae-Cistaceae-Bixaceae superclade plus its three
daughter clades. Future analyses at the species level, exploring
alternative diversification dates from both fossils and platetectonic
dynamics, are needed to refine these findings.
... The shrubland floras with highly seasonal climates (maroon pathways) are of Mediterranean type with strongly fire-adapted seeds and appeared as early as 95 Ma. Collated from Lamont and He (2012), Lamont et al. (2013), He et al. (2016a, b), Lamont et al. (2017a, b), and Pausas and Lamont (2018), with some dates revised by Tianhua He (personal communication) Proteoid Proteaceae (fireprone South Africa in particular) Figure 8 provides a dated phylogeny of part of the proteoid Proteaceae clade highlighting diversification in section Proteae in relation to climate, vegetation, fire regime, and the two-seed dormancy types, smokeand heat-released. The association of ancestral rainforest-type climates with the absence of fire and seed dormancy is clear. ...
The interaction effects between climate and fire regime in controlling the type of vegetation and species composition is well established among the Earth’s biomes. Climate and the associated fire regime are never stable for long, and annual temperatures, atmospheric carbon dioxide and oxygen levels and burn probability have varied radically over the last 350 million years. At the scale of thousands of years, floras have oscillated between spreading and retracting as climate and the dependent fire regime have fluctuated. At the scale of millions of years, distinct traits have evolved along three lines: fire resistance, fire-stimulated dormancy release and rapid postfire growth, all limited by the type of fire (as controlled by climate) and postfire weather. Eight pairings of fire and postfire-related traits resulting from the interplay between fire and climate are noted here. Smoke-released seed dormancy is beneficial on two counts: it increases the chance of recruitment under the present fireprone climate and increases the chances of survival should the wet season shift to another time of year where temperatures are higher or lower. Four pathways can be recognized with respect to the fire regimes induced by climate changes: 1) from non-fireprone to fireprone habitats (gains fire-adapted trait, 13 studies covering the last 115 million years (My) described here); 2) from a surface-fire to a crown-fire-type habitat (gains a different fire-adapted trait, 13 studies); 3) from a crown-fire-type to surface-fire-type habitat (loss of fire-adapted trait, 12 studies); and 4) from moderately burnt (crown-fire) to non-fireprone habitat, such as desert, rainforest or alpine habitats (loss of fire-adapted trait, 6 studies). Four case studies, at decreasing taxonomic rank, are used to illustrate the intimate relationship between climate change with its associated vegetation and fire-regime change as they promote adaptive trait evolution: gain then loss of heat-released seed dormancy in Dipterocarpaceae-Cistaceae-Bixaceae over 90 My, gain then loss of serotiny in Callitroid Cupressaceae over the last 65 My, gain then loss of smoke-released seed dormancy in Proteoid Proteaceae over the last 120 My, and gain then loss of resprouting and serotiny among Hakea species (Grevilleoid Proteaceae) over the last 20 My. Examples of within-species rates of migration and trait change, including a model describing increasing degree of serotiny with intensifying drought, are given. The relevance of this historical approach to current climate change and associated fire-regime alteration is discussed. Despite major threats expected to species conservation status at both the macro-(biome) and micro-(population) scales, insufficient time or opportunities remain for operation of the migration and adaptive processes described here.
... There is evidence for marine flooding of New Caledonia in the Late Cretaceous (65 Mya) to late Eocene (∼45 Mya) (Heads, 2018;Pelletier, 2007), which would favour later dispersal (e.g. by resting eggs) as the explanation for the occurrence of Lynceus at these remote islands. On the contrary, flora composition suggest that some parts of New Caledonia have remained exposed (He et al., 2016), thereby serving as a terrestrial refugium. Discordances on the complete Eocene drowning of New Caledonia are not negligible (Giribet & Baker, 2019), and vicariance could explain the disjunct distribution of the Australian/New Caledonian Lynceus clade. ...
Laevicaudatan branchiopods, also called 'smooth clam shrimps' or 'pea shrimps', are rare crustaceans found exclusively in temporary, small freshwater bodies, which stay dry most of the year. Only 42 laevicaudatan species have been described so far, 90% of which belong to the genus Lynceus. The first multilocus phylogeny of the group is provided here, based on 15 Lynceus species from North and South America, Europe, Africa, Asia, Australia and New Caledonia and using nine molecular markers (two mitochondrial and seven nuclear genes, including newly designed primers). Genetic data suggest populations of Lynceus brachyurus from Europe and North America to represent a complex of cryptic species and sister group to all other laevi-caudatans. Species from Thailand, Japan, Mongolia and China formed a distinct East Asian clade. A Southern Hemisphere (Gondwanaland) clade, composed of Chilean, Australian and New Caledonian taxa, was found weakly clustering with an African Lynceus species. Relaxed molecular clock analyses indicate a Pangean origin of Laevicaudata, with further diversification due to vicariance and the continued splitting of continents. Rostrum characters, which are particularly relevant for laevicau-datan systematics, were re-evaluated and provide morphological evidence supporting molecular clades. Our worldwide overview of Laevicaudata evolution highlights that
... In contrast to the grevilleoids, few proteoid species occur in rainforest vegetation, but Cenarrhenes occurs at the edge of rainforests in Tasmania. Pollen records show that Beauprea has a long geological history (He et al. 2016) and some extant species (Virot 1968) occur in wet forest in New Caledonia, while Eidothea grows in rainforest in north Queensland, so proteoids may have been more speciose in rainforest-type vegetation in the past than they are now. While these two genera do not have explosive pollen release the rainforest edge species Cenarrhenes nitida does, so ancestor taxa with explosive pollen release may have been more abundant in wet forests of the late Cretaceous than they are at present. ...
Pollen dispersal is the step in higher plant mating systems over which the parent plant has the least control as it is dependent on the vagaries of weather conditions (anemophily) or animal behaviour (animal pollinator activity). While many families have passive release from the anther the Proteaceae has a diversity of pollen dispersal methods. Flowers from a range of species in the Proteaceae, covering the majority of genera from each of the four main subfamilies, were examined to determine how pollen is dispersed and to gain an overall view of how male function varies within the family. This provides a basis for predicting the degree of the six likely fates of pollen released in this family. Only one group (subfamily Persoonioideae) and four genera in one other subfamily (Proteoideae) dispense pollen directly from the anthers onto a flower visitor. Five genera in the Proteoideae have explosive pollen release, while Symphionema may require vibration to release the pollen. All the remaining Proteoideae genera, the single species of Bellendenoideae, and all genera of the Grevilleoideae (except Sphalmium) have a pollen presenter where pollen is dispersed from the style of the flower. Ancestral Proteaceae were likely to have been insect pollinated and had relatively small flowers. Taxa with explosive pollen release may have evolved early in the family and may have been more abundant early in the fossil record. However, the taxa with pollen presenters became much more abundant throughout the Tertiary when many developed robust gynoecia that can accommodate larger vertebrate pollinators.
... Estimating the timing and ancestral areas of lineages remains a major frontier for biology and can be especially informative as to how faunas are assembled in geographically isolated regions with high endemism like New Zealand (e.g. [1,2]). The highly productive oceans of the Southwest Pacific today attract seabirds from across the world [3]. ...
... Diagnosis. Referred to Eudyptes based on (1) strong sigmoid curvature of jugal bar, (2) presence of shelf of bone bounding the salt gland fossa, (3) greatly deepened temporal fossae, (4) strongly shortened tarsometatarsus (ratio of length to proximal width less than 2.0) and (5) moderately deep sulcus between metatarsals II and III. Characters 1, 2 and 4 also occur within Pygoscelis, which differs from Eudyptes in exhibiting very weakly developed temporal fossae, partial or complete fusion of the ilia to the synsacrum, and a shallow sulcus between metatarsals II and III. ...
New Zealand is a globally significant hotspot for seabird diversity, but the sparse fossil record for most seabird lineages has impeded our understanding of how and when this hotspot developed. Here, we describe multiple exceptionally well-preserved specimens of a new species of penguin from tightly dated (3.36-3.06 Ma) Pliocene deposits in New Zealand. Bayesian and parsimony analyses place Eudyptes atatu sp. nov. as the sister species to all extant and recently extinct members of the crested penguin genus Eudyptes. The new species has a markedly more slender upper beak and mandible compared with other Eudyptes penguins. Our combined evidence approach reveals that deep bills evolved in both crested and stiff-tailed penguins (Pygoscelis) during the Pliocene. That deep bills arose so late in the greater than 60 million year evolutionary history of penguins suggests that dietary shifts may have occurred as wind-driven Pliocene upwelling radically restructured southern ocean ecosystems. Ancestral area reconstructions using BioGeoBEARS identify New Zealand as the most likely ancestral area for total-group penguins, crown penguins and crested penguins. Our analyses provide a timeframe for recruitment of crown penguins into the New Zealand avifauna, indicating this process began in the late Neogene and was completed via multiple waves of colonizing lineages.
... Most publications dealing with paleobiogeography of Grande Terre -New Caledonia are based on the assumption that the archipelago separated from Australia (Gondwana) at around 84 Ma during Late Cretaceous time, when the Tasman Sea opened, and was totally submerged (entirely submarine and devoid of any land) from Palaeocene to Late Eocene time (55 to 37 Ma), before being uplifted and emergent again since Oligocene time (Andújar et al. 2016;Grandcolas et al. 2016;Grandcolas et al. 2008;He et al. 2016;Murienne et al. 2005b;Nattier et al. 2017b;Pillon 2012). However, our current assessment of the geological record in this chapter suggests that such a scheme, based on Paris (1981), is no longer tenable. ...
New Caledonia is known as a global biodiversity hotspot. Like most Pacific islands, its modern biota is characterized by high levels of endemism and is notably lacking in some functional groups of biota. This is the result of its distinctive palaeobiogeographical history, which can be described in terms of three major episodes relating to Gondwana, Zealandia and New Caledonia. The geological record, the fossil record and the modern biota of the archipelago are all reviewed here. The geological record shows that the main island, Grande Terre, was submerged between 75 and 60 Ma. There is a 9 myr interval without any geological record between 34 and 25 Ma, immediately after the obduction of the Peridotite Nappe. Grande Terre may or may not have been submerged during this 9 myr interval. The ages given by molecular biology, independent of any geological calibration points, form a continuous spectrum from 60 Ma up to the present day. The derived lineage ages from molecular phylogenies all post-date 60 Ma, supporting the idea of the continuous availability of terrestrial environments since 60 Ma. Of the three common scenarios for the origin of the New Caledonia biota, long-distance dispersal is the most plausible, rather than vicariance or dispersal over short distances.
... However, the regular occurrence of pollen of the family Proteaceae, including Beauprea-type pollen (for example, Peninsulapollis gilii, Beaupreaidites), which are absent from the Tupuangi Formation, suggest that the ASE core is slightly younger than 89 Myr old. Recent molecular phylogenetic reconstructions indicate an early Antarctic-Southeastern Australian origin of Beauprea (~88 Ma), whereas the oldest palynological record of these angiosperm fossils on Antarctica and Australia date back to 81.4 Ma and 83.8 Ma, respectively 29 . ...
The mid-Cretaceous period was one of the warmest intervals of the past 140 million years1–5, driven by atmospheric carbon dioxide levels of around 1,000 parts per million by volume6. In the near absence of proximal geological records from south of the Antarctic Circle, it is disputed whether polar ice could exist under such environmental conditions. Here we use a sedimentary sequence recovered from the West Antarctic shelf—the southernmost Cretaceous record reported so far—and show that a temperate lowland rainforest environment existed at a palaeolatitude of about 82° S during the Turonian–Santonian age (92 to 83 million years ago). This record contains an intact 3-metre-long network of in situ fossil roots embedded in a mudstone matrix containing diverse pollen and spores. A climate model simulation shows that the reconstructed temperate climate at this high latitude requires a combination of both atmospheric carbon dioxide concentrations of 1,120–1,680 parts per million by volume and a vegetated land surface without major Antarctic glaciation, highlighting the important cooling effect exerted by ice albedo under high levels of atmospheric carbon dioxide. Multi-proxy core data and model simulations support the presence of temperate rainforests near the South Pole during mid-Cretaceous warmth, indicating very high CO2 levels and the absence of Antarctic ice.
... The presence of Cyclaxyra as a relict may help to explain why certain beetle lineages, especially fungus-associated groups, survived in New Zealand. While lineage survivorship or stasis may be facilitated by extrinsic factors such as minimal tectonic activity, isolation and relatively constant climate [49,50], these may not necessarily be factors that promoted relictualism in New Zealand because of its extreme geological, topographic and climatic history [40]. Diet or habitat specialization may explain the remarkable shifts in diversification rates [51] over the long geological history of insects [52]. ...
New Zealand is an island continent that completed its split from the Gondwanan continent at 52 Ma, harbouring an iconic biota of tuatara, kiwi and weta. The sooty mould community is a distinctive trophic element of New Zealand forest ecosystems that is driven by plant-feeding sternorrhynchan Hemiptera. These produce honeydew, which supports fungal growth, which in turn supports numerous endemic invertebrates, including endemic New Zealand beetle families. Ancient New Zealand insect fossils are rare but a single fossil of a sooty mould cyclaxyrid was recently described from Cretaceous Burmese amber, a family that was previously known from two extant New Zealand species. Well-preserved fossils like this one are recasting Earth history, and, based on a wealth of additional specimens, we re-evaluate the taxonomy of Cretaceous cyclaxyrids and one Eocene species here transferred to Cyclaxyridae. Cyclaxyridae are highly tied to the sooty mould community and have now been discovered to occur in disparate biogeographic realms in deep time. Our discovery indicates that the family, and perhaps the sooty mould community in general, was widespread in Pangaea from at least the Cretaceous and survived as a relict in New Zealand. Persistence of a sooty mould ecosystem in New Zealand and fungal specialization may not necessarily be an evolutionary ‘dead-end’ for cyclaxyrids and other insects.
