Morphological and molecular assessment of Aprasia fusca and A. rostrata (Squamata: Pygopodidae), with a description of a new species from the Lake MacLeod region, Western Australia

Abstract

-The Australian pygopodid genus Aprasia comprises a group of small, morphologically conservative, worm-like fossorial lizards, many of which are distributed along the west coast of the continent. This study re-examines the taxonomic distinctiveness of the two most northerly occurring species in Western Australia: A. fusca and A. rostrata, which are very similar in morphology. A combined morphological and allozyme analysis revealed these two species to be conspecifi c with A. rostrata considered a senior synonym of A. fusca. As a consequence, we have redescribed A. rostrata. The allozyme analysis also revealed a new species, named here as Aprasia litorea sp. nov. This species occurs in the Lake Macleod region, well to the south of its congener, A. rostrata, and the two species are diagnosable using a conservative suite of morphological and meristic characters.

Taxonomic resolution of the Aprasia repens species-group (Squamata: Pygopodidae) from the Geraldton Sandplains: a description of a new species and additional mainland records of A. clairae

“…In general aspects of morphology, including the elongate body and protrusive rostral 'beak', these specimens resemble A. rostrata (sensu Maryan et al 2013b); the most northerly distributed member of the A. repens species-group. However, the southern sandplains population differs from A. rostrata and all other members of the A. repens species-group on both molecular and morphological criteria.…”

“…These tissues were incorporated into an extended allozyme study that also included all previous analysed Aprasia tissues (Maryan et al 2013a(Maryan et al , 2013b as well as some previously uncharacterised samples of the A. repens species-group tissues from the central west coast of Western Australia. The allozyme study also included exemplars of all other species of Aprasia, some of which were not included in previous studies.…”

“…Allozyme electrophoresis of liver homogenates was undertaken as described in Richardson et al (1986) for the same suite of enzymes as previously employed (Maryan et al 2013a(Maryan et al , 2013b. As in our earlier studies, we fi rst used an individual-based analytical procedure (stepwise Principal Coordinates Analysis: PCO), before subsequently undertaking taxon-based assessments of genetic affinities (Neighbour-joining tree).…”

“…Sex of individuals was determined by visual inspection of everted hemipenes and postcloacal spurs in males, presence of eggs in heavily gravid females or internal examination of gonads. Head scale defi nitions follow those used by Storr et al (1990), and methods of scale counting and morphometric measurements follow those used by Maryan et al (2013aMaryan et al ( , 2013b, with two additional measures: body width and body depth.…”

“…The fi rst outcome of this work was the description of A. clairae from single localities on the Houtman Abrolhos islands and the adjacent mainland near Dongara (Maryan et al 2013a). A second outcome was the description of A. litorea from the Lake MacLeod region, and the synonymising of A. fusca with A. rostrata (Maryan et al 2013b). During these studies several other unresolved taxonomic issues were noted within the A. repens species-group, including the identity of morphologically distinctive specimens from localities at the northern edge of the range of A. repens (Maryan et al 2013a).…”