New Australian Taxa

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Phylogenetic relationships of north-eastern Australian earless dragons (Agamidae: Tympanocryptis spp.), with description of three new species.

Kirilee Chaplin (1,2), Steve K. Wilson (3), Joanna Sumner (1), & Jane Melville (1*)

(1) Department of Sciences, Museums Victoria, Melbourne, Australia.
(2) University of Melbourne
(3) Queensland Museum

*jmelv@museums.vic.gov.au

Abstract

Earless dragons (Tympanocryptis spp.) are found in most environments across the Australian continent, with the 21 currently described species inhabiting a variety of ecological niches, from stony desert to tropical woodland or cracking clay savannahs. Recent work has indicated a revision of the taxonomy of north-eastern Australian earless dragons is required. Focussing on this geographic region, we use the mitochondrial ND2 gene (987bp) to investigate the phylogenetic relationships among currently described earless dragons and newly delimited putative species, with an assessment of broad biogeographic divisions. We found significant structure across the north-eastern Australian lineages, with deep divergence between lineages occurring in the inland Great Artesian Basin region and more coastal Great Dividing Range. Regional diversification is estimated to have occurred in the late Miocene with subsequent Plio-Pleistocene speciation. The diversity of the north-eastern Australian earless dragon group is consistent with that seen in other areas of historic aridification with habitat expansions and contractions, including the Western Australian Tympanocryptis species group. Based on these data, we describe three new species of Tympanocryptis from the cracking clay grasslands of the Darling Riverine Basin and Queensland Central Highlands regions, and the stony open eucalypt woodlands on the Einasleigh Uplands. The revision of these north-eastern Australian earless dragon species provides further taxonomic clarity within the Tympanocryptis genus.

Publication date and citation

Earless dragons (Tympanocryptis spp.) are small, terrestrial agamid lizards endemic to Australia (Melville and Wilson 2019), with 21 species currently described. Although the genus is found in a range of habitats throughout the continent, each species is restricted to a certain ecological niche, including the stony regions of Western Australia, the arid interior, the Nullabor Plain, and tropical and temperate grasslands and woodlands (Shoo et al. 2008, Stevens et al. 2010, Melville et al. 2014, Doughty et al. 2015; Melville et al. 2019a; Melville et al. 2019b).

 

Earless dragons have diversified and adapted to region-specific arid conditions throughout Australia since the late Miocene, with broad scale radiations across the continent and subsequent geographically localised divergence of lineages in specific habitats or ecological niches (Shoo et al. 2008). Habitat corridors were a significant factor in the speciation of many arid interior and desert-based taxa during the late Miocene and Pliocene (Chapple and Keogh 2004, Byrne 2008, Mossop et al. 2015, Jobson et al. 2017), including several of the Western Australian Tympanocryptisspecies (Pianka 1972, Shoo et al. 2008, Doughty et al. 2015). Similarly, climatic oscillations during the Plio-Pleistocene drove expansions of the inland arid grasslands and contractions of the coastal humid rainforests in north-eastern Australia (Stocker and Unwin 1989, Kershaw 1994, Travouillon et al. 2009). Dated fossil evidence of Tympanocryptisspp. has been found as far east as the Mount Etna caves near Rockhampton (Hocknull 2005), suggesting that arid habitat corridors or grassland expansions had reached near-coastal areas prior to the late Pleistocene.

 

Several studies have focussed on species delimitation in earless dragon (Smith et al. 1999, Shoo et al. 2008, Melville et al. 2014, Doughty et al. 2015, Melville et al., 2019a; Melville et al. 2019b; Chaplin et al. 2019). However, a revision of the taxonomy of north-eastern Australian Tympanocryptisspecies is still required. There are currently five earless dragon species described in this region; T. intimadistributed throughout the inland arid stony desert areas, T. tetraporophora in stony shrubland and clay grassland areas, and T. wilsoni, T. condaminensis and T. pentalineata on cracking clay grasslands near Roma, the Darling Downs and Normanton, respectively.

 

Recent work (Chaplin et al. 2019), incorporating genomics & morphological assessments using geometric morphometrics, provided strong evidence there are three undescribed lineages (A, B and C) occurring in the Darling Riverine Basin, Queensland Central Highlands and Einasleigh Uplands, respectively (Fig. 1). However, this genomic work does not provide insight into the evolutionary relationships of these putative species within the context of the whole Tympanocryptis genus. Thus, we undertook an assessment of the phylogenetic relationships among all Tympanocryptis species, using mtDNA (987bp), including these new lineages, with detailed focus on north-eastern Australia. Finally, we provide a comprehensive taxonomic treatment of these three putative species, including morphological quantification.

Materials & Methods

Sampling

The three putative Tympanocryptis species (A, B and C) were sampled throughout their known ranges (Fig. 1). To determine the phylogenetic relationships within the genus we also incorporated samples from all other Tympanocryptis species groups, through additional samples from Museums Victoria, Queensland Museum and Western Australia Museum, or GenBank data from previously sequenced samples. Amphibolurus muricatus, Rankinia diemensis and Pogona vitticeps were used as outgroups. Locality data, museum registration numbers and GenBank accession numbers of all samples utilised in this study are listed in Supplementary Table 1.

 

Laboratory Protocols

Genomic DNA was extracted from either tail tissue or liver samples using the Qiagen Blood & Tissue Kit (Qiagen, Hilden, Germany) as per manufacturer guidelines. The mitochondrial gene ND2 (987bp) was amplified using the primers (Metf.1 and COIr.aga) and protocols described in Shoo et al. (2008) in a Bio-Rad MyCycler Thermal Cycler (Bio-Rad, California, USA). Negative controls were used in each PCR run. Amplification products were visualised on a 1.2% agarose gel with Sybr SAFE (Invitrogen, California, USA), then purified using ExoSAP-IT (Thermo-Fisher, California, USA) as per manufacturer guidelines, and sent to Macrogen (Seoul, South Korea) for sequencing. Sequence chromatograms were edited and aligned in Geneious 6.1.8 (Biomatters, Auckland, New Zealand).

 

Phylogenetic Analysis

Pairwise uncorrected genetic distances for the ND2 alignment were calculated in Mega7 (Kumar et al. 2016), with the codon frame set as the 3rd nucleotide position. Where more than one sample was present for a species, the clade was collapsed into a group prior to analysis. A Bayesian phylogeny of ND2 was produced using MrBayes (Huelsenbeck and Ronquist 2001) on the CIPRES Science Gateway (Miller et al. 2010), with two runs of four independent MCMC chains (each 50,000,000 generations long, sampled every 1,000 generations), under a GTR+I+G model with flat priors and no partitioning scheme (determined by the corrected Akaike Information Criterion (AICc) on PartitionFinder2 (Lanfear et al. 2017) on the CIPRES Science Gateway). Tracer v1.6 (Rambaut et al. 2014) was used to check for stationarity and convergence of the chain outputs. The trees were subject to a 25% burn-in in MrBayes, summarised and posterior probabilities obtained.

 

External Morphology

Seventeen meristic and metric characters previously used in Tympanocryptistaxonomy (Melville et al., 2014) and thought to be potentially diagnostic were recorded the three putative species. Electronic callipers were used for all morphological measures to the nearest 0.1mm and all bilateral counts and measurements were recorded on the left side (where possible) and analyses were run in SYSTAT v.13.2. A linear regression was performed on snout-vent length against all other measurements to standardise for size, and the residuals used in further analyses. A Discriminant functional analysis (DFA) was conducted to determine which morphological variables best discriminate between the three putative species.

 

Taxonomy

All available specimens for the putative species (A, B and C) were examined. Seventeen meristic and metric characters previously used in Tympanocryptis taxonomy (Melville et al. 2014, Doughty et al. 2015) and thought to be potentially diagnostic were recorded (Table 3). Electronic callipers were used for all morphological measures to the nearest 0.1 mm and all bilateral counts and measurements were recorded on the left side only.

Results

Phylogenetic Relationships

Previously published phylogenomic data, based on >8000 SNPs (Chaplin et al., 2019), provides strong evidence of the evolutionary independence of the putative species (A, B and C), however this published work did not provide the overall phylogenetic placement of these putative species within Tympanocryptis. Our phylogenetic analysis of all Tympanocryptis lineages and the three putative species (A, B and C) indicate all taxa are highly supported as monophyletic (Fig. 2), with uncorrected sequence divergence between taxa ranging from 3.4% to 15.5% (Supplementary Table 2). Genetic clades corresponded with previously published phylogenetic relationships (Fig. 2): the “Macra” group (T. macra); the Pebble dragons (T. centralis, T. intima, T. cephalus, T. fortescuensis, T. diabolicus, T. gigas and T. pseudopsephos); and the “Lineata” group (T. lineata, T. houstoni, T. pinguicolla, T. mccartneyi, and T. osbornei). A fourth lineage (the “Tetraporophora” group), which occurs in central and north-eastern Australia, is that covered in the current study.

 

Our analyses recovered two clades within the “Tetraporophora” group: one associated with the inland Great Artesian Basin (T. tetraporophora, Species A, T. condaminensis, T. wilsoni and T. pentalineata) and a second with the coastal Great Dividing Range (Species B and C). Mean uncorrected pairwise sequence divergence between the Great Artesian Basin (GAB) and Great Diving Range (GDR) clades was 10.6%, with deep divergences between putative species within each clade. The GDR clade is moderately supported as monophyletic (Bayesian posterior probability of 0.95; Fig. 2), with 13.5% sequence divergence between taxa B and C (Table 2). Conversely, the phylogenetic relationships between lineages within the GAB clade are not fully resolved (low Bayesian posterior probabilities, Fig. 2), although each putative species is strongly supported as monophyletic (Bayesian posterior probability of 1.00).

The GAB species group has relatively low sequence divergence between lineages compared with the GDR clade. T. condaminensis is the most basal taxon of this group with the lowest pairwise divergences of approximately 4% , while T. pentalineata has the highest levels of divergence, including 7.0% from the most closely related sister lineage to this species: T. wilsoni (Table 2, Fig. 2). Each of these species has similar intra-specific lineage divergence, observed in the length of the collapsed species clades, except for T. tetraporophora, which exhibits substantial intra-specific clade divergence (Fig. 2).

 

External Morphology

Significant differences in cranial skull shape has already been documented (Chaplin et al., 2019) in the putative species (A, B, and C), with Species A have a more spherical orbital and temporal region, while Species B and C have flatter medial regions. Additionally, Species C has a blunter snout that Species B, which has a flatter more elongated head. As well as these differences in cranial skull shape, visual inspection of external morphology of putative species (A, B and C) revealed clear differences in dorsal scalation. There are differences in number and shape of enlarged spinous scales and also whether or not scales are imbricate (further detailed in taxonomic section of this paper). In addition, ventral scales on the torso differ between the putative species with Species C having strongly keeled scales, while the other two have weakly keeled or smooth scales. There is also differentiation based on femoral pores, with Species A having two femoral pores (one on each side), which are absent in the other two species. Finally body patterning differed between putative species, with differences in the presence/absence and nature of the dorsolateral, vertebral and lateral stripes and also the width of the dark crossbands on the body (detailed fully in the taxonomic section).

 

We also undertook multivariate analyses of external morphological measures to discriminate between putative species. A Discriminant Function Analysis (DFA) of the three putative species (A, B and C) significantly distinguished groups based on external morphology (Wilks' λ8, 2, 56 = 0.071, F16,98 = 16.860, p<0.001). The DFA correctly classified 97% of animals (2/59 specimens) into the assumed a priori species classes, with only two Species A animals being incorrectly classified, one as Species B and one as Species C (figure 6). Canonical factor 1 (93.1% of variance), when corrected for within group variance, was associated with head width, neck width and hindlimb length, where Species C had wide heads, narrow necks and short hindlimbs, while Species B had narrow heads, wide necks and long hindlimbs. On Canonical factor 1, Species A was intermediate between Species B and C. Canonical factor 2 (6.9% of variance), which did not separate species significantly, was associated with tail length and neck width, where high scores had long tails and narrow necks.

 

Taxonomic Decisions

Our data, which incorporates a mtDNA phylogeny of Tympanocryptis and external morphological analysis of putative species, combined with previously published evidence, including multilocus phylogeography, phylogenomics (SNPs), geometric morphometric analysis of cranial shape using micro x-ray CT scans and external morphological assessment of other Queensland species (Melville et al., 2014; Chaplin et al., 2019; Melville et al., 2019b), shows that the putative species (A, B, and C) are paraphyletic and the current taxonomy does not recognise these lineages. Using an Integrative Taxonomic assessment criteria (ITAX), previously used in Tympanocryptis (Melville et al., 2014), we identify the four existing named taxa and three additional unnamed species (figure 8). We used the criteria for assessment outlined in Melville et al. (2014), incorporating not-necessarily sympatric sister species, where at least two lines of independent evidence were required to delimit taxa. For all lineages covered in our ITAX assessment we provide at least four lines of evidence (mtDNA, SNPs, external morphology and geometric morphometric analysis of cranial shape). Based on this assessment, we recognise three new species of earless dragons: Tympanocryptis darlingensis sp. nov. (Species A), Tympanocryptis hobsoni sp. nov. (Species B) and Tympanocryptis einasleighensis sp. nov. (Species C).

Discussion

Divergence times between these earless dragon species of north-eastern Australia are probably similar to other Tympanocryptis (Melville et al. 2007, Hugall et al. 2008, Shoo et al. 2008, Doughty et al. 2015). Using a rough estimate of 2% divergence per million years (Brown et al. 1982, Wilson et al. 1985), regional divergence times likely occurred during the late Miocene and between lineages during the Plio-Pleistocene (Fig. 2), which corresponds to previous estimates within the genus (Shoo et al. 2008, Melville et al. 2014, Doughty et al. 2015). During the Plio-Pleistocene, climatic fluctuations in north-eastern Australia would have shaped diversification and speciation of Tympanocrpytis within this region (Price 2012). The aridification and expansion of grasslands from inland to coastal areas resulted in the restriction of rainforest-specialist taxa to refugia, and vice-versa as the environmental oscillations continued (Martin 1982, Joseph et al. 1995, James and Moritz 2000). The extinction of many species occurred during this period of instability, although the diversification of more suitably adapted species (especially arid and semi-arid taxa) replaced these losses in the community (Hocknull et al. 2007). These shifts in community composition and species turnover have been well-documented throughout north-eastern Australia, including through dated fossil studies of faunal assemblages (Hutchinson and Mackness 2002, Hocknull 2005, Price et al. 2011). Fossil evidence of Tympanocryptis spp. near Rockhampton on the eastern coast indicate that previous earless dragon species or populations were widely distributed (Hocknull 2005), and the ranges of the extant Tympanocryptisspecies in north-eastern Australia are likely to be a relic of these Plio-Pleistocene climate oscillations.

 

The two GDR species form one of the most highly diverged clades within Tympanocryptis, with particularly long branches in the mitochondrial phylogeny indicating a deep divergence. These two species are the only north-eastern Australian species to be found on the eastern side of significant upland areas of the GDR (Fig. 3). While T. condaminensis is found on the Toowoomba plateau of the GDR at higher elevations (up to 500m above sea level) than either Species B or C, the Darling Downs plains slope steadily westwards to the lowlands of the Darling Riverine Plains and Mulga Lands, encompassing the distributions of T. wilsoni, Species A and T. tetraporophora, with no abrupt elevational variations throughout these areas. The lowlands on the western side of the GDR also extend north through the Mitchell Grass Downs to the Gulf Plains, including the distribution of T. pentalineata. Thus, it is probable that divergence within and between the GAB and GDR lineages is highly correlated with geology and topography of the region. Although there have been countless studies of geographic barriers of GDR taxa along latitudinal gradients (James and Moritz 2000, Chapple et al. 2011, Pepper et al. 2014), there is surprisingly little literature published on longitudinal phylogeographic patterns of GDR taxa with sister lineages in the western plains or GAB regions.

 

There is deep divergence and geographic isolation within the GDR clade. Species B exists on the Central Highlands of Queensland, with rugged escarpments and notable areas of high elevation (including the Drummond Range to the west, Carnarvon Range to the south, and Expedition Range to the east) encircling the species’ distribution. In contrast, Species C is distributed across the Einasleigh Uplands region of northern Queensland. The Einasleigh Uplands is a rugged plateau with several escarpments and varied elevation, extending from the Atherton Tablelands in the east to the Gulf Plains in the west (White 1965, Whitehead 2010). The deep molecular divergence and disjunct distributions of Species B and C are consistent with biogeographic breaks in north-eastern Australia, such as the Burdekin Gap and St Lawrence Gap, known to be associated with phylogeographic structure of a range of other herpetofauna (James and Moritz 2000, Chapple et al. 2011, Edwards and Melville 2011, Smissen et al. 2013). Although the paleoenvironmental fluctuations between arid and rainforest conditions in this region are likely to have contributed to the geographic isolation and molecular divergence of the two GDR species, it is possible that the deep branch lengths of these taxa are indicative of intermediate population extinctions, with only remnant lineages still extant, consistent with similar documented Plio-Pleistocene community composition shifts and species turnover (Hocknull 2005).

Figure 1. Distributions of north-eastern Australian Tympanocryptis species, including inset maps of locality of specimens included in current study for three putative species (A, Band C).

Acknowledgments

Taxonomy

BULUNGU CAMPBELLI Travouillon et al. 2013

Holotype— SAM P13853 (cast UCMP 126558), right dentary with m1-4, associated right maxilla with M3, broken M4, and broken M2.

Type locality— Ngapakaldi Quarry, site code V 5858, Lake Ngapakaldi, Etadunna Formation, Ngapakaldi LF, Zone C.

Remarks—Travouillon et al. (2013) described the type of this taxon. The holotype had been previously described in a PhD thesis (Campbell, 1976), in addition to a partial M2, and a left dentary with alveoli for c1, p1-3, talonid of m1, intact m2-3 and fragment of m4, which were no longer present when Travouillon et al. (2013) described the taxon. A cast of the holotype, UCMP 126558, has since been found, and preserves the morphology of the M2, which is described below. The left dentary was found in the collection of the UCMP, and is described below.

The M2 is missing the entire metastylar shelf. StA is present and connects to the preparacrista. StB is oval, with a crest running posteriorly. StC is absent. The precise point of termination of the postparacrista is difficult to assess because the metastylar shelf is missing, but it clearly terminates posterior to StB. The protocone is posterolingual to the paracone. The preprotocrista is straight and ends at the buccal flank of the paracone. The postprotocrista is curved and ends at the tip of the small metaconule, at the buccal base of the metacone (a V-shaped break indicates the approximate position of the the metacone).

The dentary is broken just anterior to the canine, through the alveoli for two incisors, suggesting that the incisors were directly anterior to the canine with no diastema present. The canine alveolus is large, and would have housed a relatively large canine. A short diastema is present between the canine and the p1, shorter than the anterior root of p1. The p1 alveoli suggest that the p1 was long and narrow. No diastema separate the alveoli for p1 and p2. A mental foramen is present on the buccal side of the dentary below the p1 and p2 junction. The alveoli of p2 suggest that the p2 was longer and wider than the p1. No diastema separates the p2 and p3. The alveoli of p3 suggest that the p3 was shorter but wider that the p2. A second mental foramen is present below the posterior root of p3. The morphology of the m2 and m3 are as described by Travouillon et al. 2013.

BULUNGU MUIRHEADAE Travouillon et al. 2013

New material—UCR 21816, right P1; UCR 21814, right P3; UCR 21808, left M1; UCR 21809, left M2; 648-662, left M2 broken and digested; UCR 21875, left m3; UCR 21804, left p3; UCR 22012, right m2; UCR 21810, right m3; UCR 21813, left m3; UCR 21811, left m1; UCR 21815, right m3 talonid; UCR 21812, right m3.

 

Age and Stratigraphy—All new specimens (except UCR 21875 and UCR 21804) are from the type locality, Tedford Locality (Site 2), site code RV 7230, Lake Palankarinna, Etadunna Formation, Ditjimanka LF, Zone B. UCR 21875 and UCR 21804 are from Steve’s Site, RV-8447, Lake Palankarinna, Etadunna Formation, Ditjimanka LF, Zone B.

The majority of the new specimens represent parts that were already described by Travouillon et al. 2013, except for the p3, P1 and P3, the morphology of which was previously unknown and which is described here.

 

Lower Dentition— In lateral view, the p3 is ovoid in occlusal view, longer than it is wide, and crescent-shaped. The main cuspid is tall and anteriorly positioned, above the anterior root. The main cuspid is slightly curved lingually at its tip. A small anterior cuspid is present just anterior to the main cuspid. These two cuspids at not connected by any crests. Posterior to the main cuspid, a short posterior cuspid is present above the posterior root. A well defined crest connects the main cuspid to the posterior cuspid.

 

Upper Dentition— The P1 is a simple tooth with a single cusp on the centre of the crown. In occlusal view, it is ovoid, longer than it is wide. No crests are present on the crown. The roots are long and wide, and extend the length and width of the tooth below the crown. The P3 is much larger than the P1, and has three distinct cusps on its crown. The anteriormost cusp is small and rounded,with a thin bladed shelf associated with it, bordering the lingual and buccal sides of the crown, and level with the anterior half of the anterior root. The main cusp is tall and wide, centrally positioned on the crown. A crest connects the main cusp to the posterior cusp, descending the steep posterior slope of the main cusp. The posterior cusp is much smaller than the main cusp but larger than the anterior cusp. A thin bladed shelf is also associated with the posterior cusp, and surrounds the posterior half of the crown both lingually and buccally.

Figure 3. Bulungu muirheadae, UCR 21804, left p3 (A, buccal view; B, lingual view; C, occlusal view); UCR 21816, right P1 (D, buccal view; E, lingual view; F, occlusal view); UCR 21814, right P3 (G, lingual view; H, buccal view; I, occlusal view). Scale bar equals 2mm.

BULUNGU MINKINAENSIS sp. nov.

Holotype—UCR22304, left dentary with p3, m2-4.

Paratypes— JAC 00122, left M2; UCR22341, right m1.

Type Locality—The holotype and paratype JAC 00122 are from Young Bucks Quarry, RV-9002, Lake Palankarinna, South Australia. Paratype UCR22341 is from Croc-pot, RV-8502.

Age and Stratigraphy—Young Bucks Quarry and Croc-pot occur within the Etadunna Formation, Faunal Zone A or Minkina Local Fauna.

Species DiagnosisBulungu minkinaensis sp. nov. differs from B. muirheadae as follows: stylar cusp B and D are connected on M2; a small shelf is present between the metacone and metaconule on M2; stylar cusp C is absent on M2; hypoflexid shelf absent on m1; cristid obliqua terminates lingual to the protoconid at about the midpoint of the total tooth width on m2; posthypocristid is oblique to the tooth row on m3; paraconid-metaconid distance is longer than the metaconid-protoconid distance on m4; cristid obliqua terminates lingual to the midpoint of the tooth width on m4; posthypocristid on m4 is perpendicular to the tooth row; hypoconulid absent on m4. Bulungu minkinaensis sp. nov. differs from B. campbelli as follows: preparacrista terminates at base of stylar cusp B on M2; a small shelf is present between the metacone and metaconule on M2; hypoflexid shelf absent on m1; posthypocristid is oblique to the tooth row on m3; paraconid-metaconid distance is longer than the metaconid-protoconid distance on m4; posthypocristid on m4 is perpendicular to the tooth row; hypoconulid absent on m4. Bulungu minkinaensis sp. nov. differs from B. palara as follows: preparacrista terminates at base of stylar cusp B on M2; stylar cusp C is absent on M2; hypoflexid shelf absent on m1; posthypocristid is oblique to the tooth row on m3; paraconid-metaconid distance is longer than the metaconid-protoconid distance on m4; postentocristid is present on m4; cristid obliqua terminates lingual to the midpoint of the tooth width on m4. Bulungu minkinaensis sp. nov. differs from B. westermani as follows: smaller in size. Bulungu minkinaensis sp. nov. differs from B. pinpaensis as follows: preentocristid on m4 is anteroposteriorly directed; posthypocristid on m4 is perpendicular to the tooth row; entoconid on m4 is large; hypoconulid absent on m4.

Etymology—The species name minkinaensis is after the Minkina Local Fauna in which the specimens are found.

Dentary— The dentary is broken anteriorly at the posterior alveolus of p1, and posteriorly, posterior to m4. In lateral view, the dentary is curved ventrally, and relatively straight dorsally. It is deepest below m3, and widest below m4. Two mental foramina are present on the dentary, one below the posterior root of p1 (only the posterior wall of the foramen is visible on the specimen), and one below the anterior root of m1. A very short diastema (shorter than the anterior root of p2) separates the posterior root of p1 from the anterior root of p2. No diastemata are present between the teeth posterior to p2.

Lower Dentition—The p3 is a bladed tooth, with a large main cuspid, anteriorly positioned above the anterior root, and two smaller cuspids at the anteriormost and posteriormost corners of the crown. In occlusal view, the tooth is ovoid, longer than wide, and the tip of the main cusp is slightly tilted lingually. In lateral view, the tooth is crescent-shaped, with a strong crest connecting the main cuspid to the posterior cuspid. The anterior cuspid is small and rounded. The posterior cuspid is larger than the anterior cuspid, but much smaller than the main cuspid.

The m1 is much longer than it is wide. The protoconid is the tallest cuspid on the crown, followed in order of decreasing height by the metaconid, hypoconid, entoconid, paraconid and hypoconulid. The paraconid is well anterior to the metaconid, with the paracristid longer than the metacristid. The paracristid and metacristid are both oblique to the tooth row. A well-developed anterior cingulid is present anterior and parallel to the paracristid. The talonid is much wider than the trigonid, with the hypoconid more buccally positioned than the protoconid. The cristid obliqua is straight and oblique, terminating just buccal to the tip of the protoconid on its posterior flank. The posthypocristid is straight and oblique and terminates at the hypoconulid. The hypoconulid is positioned slightly posterobuccal to the entoconid and lies low on the crown. The entoconid is oval in shape, with a preentocristid descending its anterior flank and partly ascending the posterior flank of the metaconid. There is no hypoflexid shelf on the m1.

The m2 is similar in morphology to the m1 except as follows. The anterior cingulid is longer and wider. All cuspids are taller and larger in occlusal area. The paraconid is more posteriorly positioned, resulting in a shorter distance between the paraconid and metaconid and decreasing the angle at the protoconid between the paracristid and metacristid; however, the paracristid is still longer than the metacristid. The protoconid is more buccally positioned, resulting in a wider trigonid. The hypoconid is also more buccally positioned, resulting in a wider talonid. The cristid obliqua ends directly posterior to the protoconid. The posthypocristid is straight along most of its length, but curves posterolingually to join to the larger hypoconulid. The entoconid is much wider than on the m1, and the preentocristid is better developed. The hypoflexid shelf is present as a thin ridge.

The m3 is similar in morphology to the m2 except as follows. The anterior cingulid is wider. The protoconid is more buccally positioned, resulting in a longer paracristid and metacristid. The entoconid is shorter but wider.

The m4 is similar in morphology to the m3 except as follows. The anterobuccal corner of the anterior cingulid is less well-developed. The metaconid is more posteriorly positioned, and so is more distant from the paraconid. The protoconid is more lingually positioned, resulting in a shorter metacristid and paracristid. The talonid is greatly reduced, with the hypoconid reduced to a small cuspid that is positioned posterior to the midpoint of the metacristid. The cristid obliqua is straight and oblique, and terminates at the posterior flank of the metaconid. The posthypocristid is anterolingually directed and ends at the buccal flank of the entoconid. The entoconid is taller than the hypoconid and oval in shape, with the preentocristid terminating at its anterior flank and the postentocristid terminating at its posterior flank. The hypoconulid is absent. The hypoflexid is a large shelf, from the posterior flank of the protoconid to the buccal flank of the hypoconid.

Upper Dentition— The M2 is very slightly longer than it is wide (Table 1). StD is the tallest cusp on the crown, followed in order of decreasing height by StB, metacone, StD1, StE, metastyle, StA, paracone, protocone and metaconule. StA is a rounded cusp at the anterobuccal most corner of the crown, with no crest associated with it. StB is directly posterior to StA, much larger and oval in shape, and with a crest running posteriorly and ending in the ectoflexus valley. StC is not identifiable as a distinct cusp. Anterolingual to StB, a small anterior cingulum is present and extends from the posterior flank of StA to just anterior to the paracone. The paracone is directly lingual to StB. The preparacrista is well-developed and contacts StB at its lingual flank. The postparacrista connects to the premetacrista to form a complete centrocrista, its apex in line with the ectoflexus. The metacone is posterolingual to the paracone. The postmetacrista is the longest crest and contacts the metastyle posterobuccally. StD is buccal to the metacone, tear-shaped, with a single blade running posteriorly through a small rounded StE, and ending at the metastyle. StD1 is present as a small bladed crest anterior to StD. The protocone is lingual to the paracone. The preprotocrista is oblique, and ends just anterior to the lingual flank of the paracone. The postprotocrista is straight and ends at the metaconule. The metaconule is small but distinct, and positioned anterolingual to the metacone. The postmetaconulecrista descends posteriorly from the metaconule and ends at the base of the lingual flank of the metacone.

Figure 2. Bulungu minkinaensis sp. nov., holotype, UCR 22304, right dentary with p3, m2-4 (A, occlusal view; B, buccal view; C, lingual view); paratype, UCR 22341, right m1 (D, occlusal view; E, buccal view); paratype, JAC00122, left M2 (F, occlusal view; G, lingual view). Scale bars equals 2mm.

Aname pulchella Harvey & Rix, sp. nov.

ZooBank LSID: http://zoobank.org/EditNomenclaturalAct/#####

 

Holotype: AUSTRALIA: Western Australia: Madura Caravan Park, 31°54’02"S, 127°01’14"E, 12 September 2017, J.M. Waldock, M.J. Hillyer, M.S. Harvey (WAM T144388).

 

Paratype: Australia: Western Australia: 1 male, Madura Caravan Park, 31°54’02"S, 127°01’14"E, 10 September 2017, M.J. Hillyer (WAM T144353).

Big & hairy. Spines. 8 eyes. All that good stuff.

Other material: Australia: Western Australia: 1 male, Dundas Nature Reserve, Mt Andrew Track, 32°30’57"S, 122°51’45”E, dry pitfall trap, mallee, 24 October 2009, S. Comer (WAM T101551); 1 male, Dundas Nature Reserve, Mt Andrew Track, 32°30`56"S, 122°51`43"E, October 2009, dry pitfall, S. Comer (WAM T101556).

SEQUENCE DATA

Intraspecific genetic divergence for this species was low, reaching only 0.?% at COI.

 

ETYMOLOGY

The species epithet refers to the beauty of this species (pulchellus, Latin, diminutive of pulchra, beautiful, pretty, fine, lovely) (Brown 1956).

Figure 1. Aname pulchella Harvey & Rix, sp. nov., holotype male (WAM T144388).

Figure 2. Aname pulchella Harvey & Rix, sp. nov., holotype male (WAM T144388): A, cephalothorax, dorsal; B, abdomen, dorsal; C, eyes, dorsal; D, fovea, dorsal; E, sternum, ventral; F, cephalothorax, ventral; G, abdomen, ventral; H–L, left pedipalp: H, prolateral view; I, retrolateral view; J, tibia and tarsus, prolateral view; K, tibia and tarsus, ventral view; L, tibia and tarsus, retrolateral view; M–P, left leg I: M, prolateral view; N, tibia I, prolateral view; O, tibia I, retrolateral view; P, metatarsus I, prolateral view. Scale lines = 2 mm.

Tympanocryptis einasleighensis sp. nov.

Einasleigh earless dragon

Holotype. QM J96318, male, Richmond Rd, north of Esmeralda, Queensland, Australia (-18.5672, 145.5626).

 

Paratypes. (7 specimens) NMV D77187, male, Richmond Rd, north of Esmeralda, Queensland, Australia (-18.5649, 142.5646); QM J96320, male, Richmond Rd, north of Esmeralda, Queensland, Australia (-18.5645, 142.5651); QM J96322, male, Richmond Rd, north of Esmeralda, Queensland, Australia (-18.5616, 142.5682); NMV D74081, female, Richmond Rd, north of Esmeralda, Queensland, Australia (-18.5619, 142.5678); QM J96319, female, Richmond Rd, north of Esmeralda, Queensland, Australia (-18.5675, 142.5625); QM J96321, female, Richmond Rd, north of Esmeralda, Queensland, Australia (-18.5645, 142.5651); NMV D77265, female, Thornborough Rd, south of Thornborough, Queensland, Australia (-16.9991, 145.0312).

Description of holotype. SVL 54 mm. A medium-sized Tympanocryptis, with a stocky shape; short limbs, a round body, long head and blunt snout. Dorsal scales heterogeneous, with scattered enlarged scales; weakly imbricate. Enlarged scales are weakly imbricate, strongly keeled with keel terminating in weak spine; posterior edge of scale very narrowly raised. Small dorsal scales weakly imbricate, weakly to strongly keeled without terminating spine. Ventral scales weakly keeled. Indistinct, broken dorsolateral stripes running from the shoulders to pelvis. Vertebral stripe absent. Indistinct, diffuse crossbands between neck and base of tail, narrower than background colour. Approximately 12 dark bands on tail, narrower than intervening pale bands. Flanks with scattered cream flecks on darker background; lacking distinct lateral stripe. Dorsal head patterning weak and indistinct; lacks pale supra-orbital bar. Ventral patterning present; fine grey speckling under chin, extending posteriorly onto throat; lacks speckling on torso. Pre-anal pores 2, femoral pores absent; gular fold present.

Variation. Table 1 (as Species C). Vertebral, dorsolateral and lateral stripes usually absent. Broken, indistinct dorsolateral stripes in some individuals from the neck up to 1/3 of the way down the tail. If dorsal patterning present, consists of 5-6 dark narrow crossbands, poorly defined a much narrower than intervening pale background colour. Dorsal surface of head weakly or not patterned, sometimes with faint pale supra-ocular bar. Dorsal colour variable, ranging from red to light brown; spines on dorsal keeled scales varies from a light red-brown to a very dark brown-black. Males generally have stronger dorsal patterning than females. Flanks usually dark, sometimes with contrasting pale flecking or mottling. Ventral surface variable, from plain to mottling on head and gular region and in a few individuals the lateral portions of torso.

 

Comparison to other species. This distribution of T. einasleighensis sp. nov. appears not to overlap with any other Tympanocryptis species. It occupies the Einasleigh Uplands region of northern Queensland, with the closest sister taxa found over 180km away, to the south and west of Normanton (T. pentalineata, T. tetraporophora and T. intima). It can be distinguished from these species by the lack of five distinct longitudinal stripes (observed in T. pentalineata), lack of femoral pores (a key characteristic of T. tetraporophora) and scattered mucronate dorsal scales (normally in longitudinal rows in T. intima).

 

Habitat. Open eucalypt woodland on stony red rudosols or podosols, in rugged or undulating terrain.

 

Distribution. Currently known from several locations on the Einasleigh Uplands; along Richmond Rd and Inorunie Rd east of Croydon, Elizabeth Creek near Talaroo, the north-western area of Undara National Park and near Thornborough.

 

Etymology. Named for the bioregion this species occupies.

Tympanocryptis hobsoni sp. nov.

Hobson’s earless dragon

Holotype. QM J96313, male, Retro, Capella North, Queensland, Australia (-22.8606, 147.8763).

 

Paratypes. (8 specimens) QM J96314, male, Retro, Capella North, Queensland, Australia (-22.8604, 147.8761); QM J96315, male, Homelea Downs, north of Clermont, Queensland, Australia (-22.6918, 147.6768); NMV D77134, male, Homelea Downs, north of Clermont, Queensland, Australia (-22.6936, 147.6762); NMV D77135, female, Homelea Downs, north of Clermont, Queensland, Australia (-22.6948, 147.6776); QM J96317, male, Glendariwell, Gemfields, Queensland, Australia (-23.6034, 147.8247); NMV D77164, female, Glendariwell, Gemfields, Queensland, Australia (-23.6154, 147.8293); NMV D77136, male, Orana Downs, Orion, Queensland, Australia (-24.2579, 148.3510); QM J96316, female, Orana Downs, Orion, Queensland, Australia (-24.2597, 148.3468).

Description of holotype. SVL 51 mm. A medium-sized Tympanocryptis, with long limbs, a slender body, and somewhat dorsoventrally flattened skull with a blunt snout. Dorsal scales heterogeneous, with scattered enlarged scales; not imbricate. These enlarged scales are not imbricate, strongly keeled with keel terminating in spine and posterior edge of scales not raised. Small dorsal scales not imbricate, weakly keeled without terminating spine. Ventral scales are unkeeled on the head and neck, and weakly keeled on the torso. Narrow light grey dorsolateral stripes running from behind the eye to approximately a third of the way down the tail, gradually fading into background colour. Dorsolateral stripes approximately twice as wide as the vertebral stripe on the neck, narrowing to the same width as vertebral stripe on the back and tail. Continuous vertebral stripe running from neck to pelvis. Six dark brown-black dorsal crossbands between neck and base of tail, slightly narrower than pale background, disjunct across dorsal stripe. Approximately 12 dark bands on tail, approximately the same width as the intervening pale bands. Flanks with scattered cream flecks on dark background with a narrow pale lateral stripe. Dorsal surface of head strongly patterned with three dark transverse bars from supra-ocular region to snout; dark bars narrower than background colour; prominent white stripe from under eye to tympanum region. Ventral patterning absent. Pre-anal pores 2, femoral pores absent; gular fold present.

Variation. Table 1 (as Species B). Dorsolateral stripes variable, from narrow to wide and grey or cream; dorsolateral stripes often twice as wide and more prominent than vertebral stripe; dorsolateral stripes usually wider on neck becoming more narrow on back, often continuing anteriorly along neck onto head and culminating in ‘C’-shaped arc (bounded dorsally by black) to the dorso-posterior portion of the orbit. Length of dorsolateral stripes variable, terminating on first third of tail or sometimes continuing halfway down tail, while vertebral stripe terminates at pelvis. Lateral stripe usually narrow from axial to groin; although sometimes indistinct. Dorsal patterning consists of 5-6 dark crossbands usually similar width to pale crossbands but sometimes slightly narrower, usually disjunct across dorsal stripe. Dorsal head patterning usually strong although somewhat variable with some individuals having a diffuse dark transverse bars from supra-ocular region to snout and somewhat indistinct pale stripe from under eye to tympanum region. Ventral surface usually has mottling on head and gular region and in a few individuals the lateral portions of torso; some individuals lack ventral patterning. Males have longer tails and pre-anal pores can be difficult to distinguish in females.

 

Comparison to other species. The distribution of T. hobsoni sp. nov. is isolated from other Tympanocryptis taxa, with T. tetraporophora being the closest species (approximately 200 km to the west of the known range of T. hobsoni sp. nov.). However, T. hobsoni sp. nov. can easily be distinguished by the lack of femoral pores, compared with 2 femoral pores in T. tetraporophora. Additionally, T. hobsoni sp. nov. has an unusually long second toe on the hindlimbs (Table 1), compared with other Tympanocryptis species.

 

Habitat. Native grasslands or cropping fields (including wheat, sorghum and chickpea) on black vertosols.

 

Distribution. Currently known to exist in populations on cropping lands adjacent to the Dawson, Gregory, Capricorn and Peak Downs Highways on the Queensland Central Highlands, bordered by Orion in the south, Clermont in the north and Anakie in the west (Fig. 5).

 

Etymology. Named in recognition of the outstanding contributions of Rod Hobson to the conservation of Tympanocryptis species and Queensland herpetology, and his direct input into the collection and ecological understanding of this new species on the Central Highlands.

Tympanocryptis darlingensis sp. nov.

Darling earless dragon

Holotype. QM J96308 (formerly NMV D77151), male, Balonne Plains, south of St George, Queensland, Australia (-28.2638, 148.6748).

 

Paratypes. (9 specimens) NMV D77117, male, Stock route off Bollon Rd, Mitchell, Queensland, Australia (-26.4996, 147.9373); QM J96309, female, Stock route off Bollon Rd, Mitchell, Queensland, Australia (-26.4996, 147.9374); NMV D77147, male, Hortonvale, north of Cunnamulla, Queensland, Australia (-27.9525, 145.7368); QM J96311, male, Hortonvale, north of Cunnamulla, Queensland, Australia (-27.9482, 145.7405); QM J96310, female, Hortonvale, north of Cunnamulla, Queensland, Australia (-27.9463, 145.7376); NMV D77143, female, Hortonvale, north of Cunnamulla, Queensland, Australia (-27.9471, 145.7375); QM J96312, female, Balonne Plains, south of St George, Queensland, Australia (-28.2654, 148.6860); NMV D77153, female, Balonne Plains, south of St George, Queensland, Australia (-28.2654, 148.6838); NMV D77156, male, Myall Plains, Nindigully, Queensland, Australia (-28.3770, 148.6474).

Description of holotype. SVL 54 mm. A medium-sized Tympanocryptis, with a slender body and neck, moderately long limbs and tapered snout. Dorsal scales imbricate and heterogeneous, with scattered enlarged scales. These enlarged scales are strongly imbricate, strongly keeled with keel terminating in spine and posterior edge of scale very narrowly raised. Small dorsal scales weakly imbricate, weakly keeled without terminating spine. Ventral scales smooth to weakly keeled. Prominent light grey dorsolateral stripes running from the neck to approximately half way down tail, gradually fading into background colour, approximately same width as vertebral stripe. Continuous vertebral stripe running from neck to pelvis. Five dark brown-black dorsal crossbands between neck and base of tail, slightly narrow than intervening pale crossbands. Approximately 17 dark bands on tail, slightly wider than intervening pale bands. Flanks with scattered cream flecks on dark background with a narrow pale lateral stripe. Dorsal head patterning present with narrow pale supra-orbital bar. Ventral patterning present, with coarse grey mottling on the head tending for form linear white patches adjacent to jaw, faint grey mottling on upper chest and lateral areas of torso. Pre-anal pores: 2, femoral pores: 2; gular fold present.

Variation. Table 1 (as Species A). Dorsolateral stripes variable, from narrow to wide and grey or cream, often discontinuous where only visible on dark cross bands, approximately same width as vertebral stripe, which is often discontinuous or poorly defined. Length of dorsolateral stripes variable, terminating on first third of tail or sometimes continuing halfway down tail, while vertebral stripe terminates at pelvis. Usually a well-defined lateral stripe from axial to groin; although sometimes very narrow. Dorsal patterning consists of 5 dark crossbands usually wider than pale crossbands, often disjunct across dorsal stripe. Flanks from side of neck to base of tail has mottling often with dark dorsal crossbands terminating at pale lateral stripe. Dorsal head patterning present, usually with pale supra-ocular bar but sometimes very faint. Ventral surface usually has strong contrasting mottling on head and gular region and often the lateral portions of torso. Mottling on ventral surface of head is coarse and tends to form linear patches of white, towards gular region and adjacent to jaw. Some individuals have strong contrasting mottling extending onto the upper chest. Species has two femoral pores (one on each side), however, they are often difficult to find in females and sub-adults.

 

Comparison to other species. T. darlingensissp. nov., T. wilsoni and T.tetraporophora are morphologically very similar. Distribution and colour patterns are the key characters to distinguish T. darlingensis sp. nov. from the other two species. T. darlingensis sp. nov. is allopatric to T. wilsoni, which occurs east of Amby, QLD. The distribution of T. darlingensis sp. nov. is approximately~30km to the west, on the western side of the Maranoa River in Mitchell. These two species are very similar in appearance but can be somewhat distinguished based on colour and patterning,

T. darlingensissp. nov. is probably sympatric with T. tetraporophora, however samples of T. tetraporophora from the Darling Basin region may have been misidentified and may actually be T. darlingensis sp. nov. Body colour of T. darlingensis sp. nov. is generally slightly greyer or browner than the red-brown colour of T. tetraporophora from sympatric regions.

 

Habitat. Native grasslands or cropping fields (including wheat, sorghum and chickpea) on grey, brown or red-brown vertosols in Queensland. It is assumed to occupy similar habitat in New South Wales.

 

Distribution. The distribution of T. darlingensis sp. nov. is not yet fully understood but known to occur in the Mulga Lands and Darling Riverine Basin bioregions. Known locations from samples confirmed by molecular data include near Mitchell, Cunnamulla, St George and Nindigully in Queensland, and Lightning Ridge, Tilpa and White Cliffs in New South Wales (Fig. 4).

 

Etymology. Named for the Darling Riverine Plains and Darling Basin this species inhabits.

Hibbertia arenaria K.R.Thiele sp. nov.

Type: Western Australia [locality withheld for conservation reasons], 23 September 2001, J.W. Horn 4116 (holo: PERTH 06232922; iso: CANB, MEL).

Spreading to straggling shrubs to 0.5 m high; young branchlets comprising densely packed, thickened, pubescent, persistent leaf bases. Leaves erect at first then spreading, scattered, crowded at stem apices, oblong, 4–8 mm long, 1.4–2 mm wide, the margins strongly recurved to the thickened, prominent midrib, obscuring the abaxial lamina; adaxial surface not tuberculate, sparsely hairy to glabrous except for dense, curled-woolly hairs at base; abaxial surface {indumentum}; apex obtuse and pungently apiculate. Flowers sessile, terminal, closely subtended by crowded leaves; flower-subtending bracts 6–7, reddish-brown, scarious, narrowly triangular, acute, the primary bract 2.5–3.5 mm long. Sepals 5, ovate, 5–5.5 mm long, moderately to densely appressed-pubescent; midribs prominent; outer sepals pungently acuminate to shortly mucronate; inner sepals similar to the outer but less acuminate and broader. Petals 5, yellow, obovate, 5.5–8 mm long, deeply emarginate. Stamens 10, all on one side of the gynoecium, their filaments ±fused; anthers rectangular, c. 2 mm long, dehiscing by introrse, longitudinal slits. Staminodes absent. Carpels 2; ovaries compressed-globular, densely pubescent; styles curving excentrically from the carpel apex, 1.2–1.8 mm long. Ovules 4 per carpel. Fruiting carpels and seeds not seen.

Other specimens examined. WESTERN AUSTRALIA: [localities withheld for conservation reasons] 30 June 2005, G.F. Craig 6681 (PERTH 7313691); 23 Sep. 2001, J.W. Horn 4113 (PERTH 6232914); 24 Sep. 2001, J.W. Horn 4122 (PERTH 6232949); 8 Aug. 1978, D. Monk 326 (PERTH 3094065).

Diagnostic features. May be discriminated from all other species of Hibbertia in Western Australia by the combination of ericoid leaves, sessile flowers, silky sepals {check}, ten stamens and four ovules per carpel.

 

Phenology. Flowering specimens have been collected in June, August and September.

 

Distribution and habitat. Collected from scattered localities from west of Holt Rock eastwards towards 90 Mile Tank. Occurs on undulating plains on sandy, loamy or somewhat clayey soils over laterite, in proteaceous-myrtaceous kwongan heath dominated by species of Allocasuarina, Hakea, Melaleuca, Micromyrtus, Beaufortia, Banksia, Leptospermum, Isopogon, Petrophile and Callitris.

Conservation status. Hibbertia arenaria is known from only four localities, none of which is in a conservation reserve. A listing of Priority One under the Conservation Codes for Western Australian Flora (Smith and Jones, 2018) is recommended.

 

Etymology. From the Latin arenarius(a sandy place), in reference to the habitat in contradistinction to the rocky upland occupied by H. axillibarba.

 

Affinities. Hibbertia arenaria and H. axillibarba are superficially similar. They are very readily separated by their leaf shape: in H. arenaria the leaf margins are recurved to and closely abut the broad, prominent midrib, while in H. axillibarba the margins are recurved to each other (at least when dried) so that the midrib is hidden.

However, they are unlikely to be closely related. Ovule number appears to be conservative in natural groupings of Hibbertia; the two ovules of H. axillibarba and four in H. arenaria suggests that they are not close. Horn (2005) included H. arenaria in a molecular phylogeny of Hibbertia, where it grouped with H. ancistrotricha, a species that also has four ovules but a very different sepal indumentum (of hooked hairs), leaves that are obtuse and very shortly mucronate, and shortly pedicellate flowers. However, sampling of species in the Horn phylogeny was incomplete, and our knowledge of phylogenetic relationships in Hibbertiaremains preliminary.

Figure 1. Distribution of Hibbertia arenaria sp. nov. (circles) and H. axillibarba (star) in south-west Western Australia

References