Revision of zigzag geckos (Diplodactylidae: Amalosia) in eastern Australia, with description of five new species

Geckos of the genus Amalosia Wells & Wellington, 1984 occur across eastern and northern Australia. Only five species are described but additional diversity has been recognised for some time. Here we assess species diversity in eastern Australia, using morphological and genetic (ND4 mtDNA) data. We describe five new species, all morphologically distinct and highly genetically distinct (>25% divergence). Amalosia hinesi sp. nov. is found in woodlands on the western side of the Great Dividing Range in south-east Queensland and north-east New South Wales. Amalosia saxicola sp. nov. is a large species found on rocks in the MackayTownsville areas of mid-east Queensland, including on many offshore islands. Amalosia nebula sp. nov. is restricted to rocky areas in upland sclerophyll forest of the Wet Tropics region of north-east Queensland. Amalosia capensis sp. nov. is a small species found in the northern half of Cape York Peninsula. Amalosia queenslandia sp. nov. is a small species that is widespread through woodlands over much of eastern and central Queensland. These species are diagnosed from other Amalosia species in eastern Australia, including A. cf. rhombifer which occurs in north-western Queensland. Amalosia cf. rhombifer is part of the clades comprising the remainder of the A. rhombifer complex across the Northern Territory and Western Australia, which will be dealt with separately. Herein, we also we also synonymise the monotypic genus Nebulifera with Amalosia. This revision brings the number of Amalosia species to ten.

Reappraising the evolutionary history of the largest known gecko, the presumably extinct Hoplodactylus delcourti, via high-throughput sequencing of archival DNA

Hoplodactylus delcourti is a presumably extinct species of diplodactylid gecko known only from a single specimen of unknown provenance. It is by far the largest known gekkotan, approximately 50% longer than the next largest-known species. It has been considered a member of the New Zealand endemic genus Hoplodactylus based on external morphological features including shared toe pad structure. We obtained DNA from a bone sample of the only known specimen to generate high-throughput sequence data suitable for phylogenetic analysis of its evolutionary history. Complementary sequence data were obtained from a broad sample of diplodactylid geckos. Our results indicate that the species is not most closely related to extant Hoplodactylus or any other New Zealand gecko. Instead, it is a member of a clade whose living species are endemic to New Caledonia. Phylogenetic comparative analyses indicate that the New Caledonian diplodactylid clade has evolved significantly more disparate body sizes than either the Australian or New Zealand clades. Toe pad structure has changed repeatedly across diplodactylids, including multiple times in the New Caledonia clade, partially explaining the convergence in form between H. delcourti and New Zealand Hoplodactylus. Based on the phylogenetic results, we place H. delcourti in a new genus.

A new gecko from the earliest Eocene of Dormaal, Belgium: a thermophilic element of the 'greenhouse world'

We here describe a new gekkotan lizard from the earliest Eocene (MP 7) of the Dormaal locality in Belgium, from the time of the warmest global climates of the past 66 million years (Myr). This new taxon, with an age of 56 Myr, together with indeterminate gekkotan material reported from Silveirinha (Portugal, MP 7) represent the oldest Cenozoic gekkotans known from Europe. Today gekkotan lizards are distributed worldwide in mainly warm temperate to tropical areas and the new gecko from Dormaal represents a thermophilic faunal element. Given the Palaeocene-Eocene thermal maximum at that time, the distribution of this group in such northern latitudes (above 50° North - the latitude of southern England) is not surprising. Although this new gekkotan is represented only by a frontal (further, dentaries and a mandibular fragment are described here as Gekkota indet. 1 and 2-at least two gekkotan species occurred in Dormaal), it provides a new record for squamate diversity from the earliest Eocene 'greenhouse world'. Together with the Baltic amber gekkotan Yantarogekko balticus, they document the northern distribution of gekkotans in Europe during the Eocene. The increase in temperature during the early Eocene led to a rise in sea level, and many areas of Eurasia were submerged. Thus, the importance of this period is magnified by understanding future global climate change.

Altitude impacts body size but not age in a gecko

Animals' age and size-related life-history traits are influenced by a variety of factors. In connection with climate, the effect of altitude on demographic parameters may differ among different populations of the same species. In the present study, it was analyzed that how body size and longevity of the Asia Minor thin-toed gecko, Mediodactylus heterocercus (Blanford, 1874), vary along with an elevational gradient in Turkey. For this purpose, a total of 138 (52 males, 75 females, and 11 young) M. heterocercus specimens from 11 different populations were analyzed. Populations at inter-mediate altitude had shorter lifespans than in both low and high elevations (marginal environments). Furthermore, the adult life expectancy (ESP), which indicates the expected lifespan of individuals having sexual maturity, was higher in high altitude populations (ESP: 6.59 years) than in intermediate populations (ESP: 5.40 years) and low altitude populations (ESP: 6.01 years). The results of the study suggest that Asia Minor thin-toed geckos' body size increases with altitude, but their age does not.

Determining the Effects of Serial Injections of Pregnant Mare Serum Gonadotropin on Plasma Testosterone Concentrations, Testicular Dynamics, and Semen Production in Leopard Geckos (Eublepharis macularius)

Reptiles are highly susceptible to anthropogenic activities as a result of their narrow geographical ranges and habitat specialization, making them a conservation concern. Geckos represent one of the mega-diverse reptile lineages under pressure; however, limited assisted reproductive technologies currently exist for these animals. Exogenous pregnant mare serum gonadotropin (PMSG) has been found to exhibit follicle stimulating hormone-like action and has been routinely used to alter reproductive hormones of vertebrates in assisted reproductive protocols. The purpose of this study was to determine the effects of serial injections of 20 IU and 50 IU PMSG on circulating testosterone concentrations, testicular dynamics, and semen production in a model species of gecko. Twenty-four captive-bred, adult, male leopard geckos (Eublepharis macularius) were divided into three treatment groups and administered a once-weekly injection of either PMSG or saline for a total of nine weeks. Ultrasonographic testicular measurements, electrostimulation for semen collection, and venipuncture were performed on days 0, 21, 42, and 63. Right unilateral orchidectomies and epididymectomies were performed in all animals on day 63; tissues were submitted for histopathology. PMSG treated geckos had significantly higher testicular volumes and weights, spermatozoa motility, and spermatozoa concentrations compared with controls. However, there were no significant differences in testosterone concentrations by treatment or time. Under the conditions outlined, PMSG is effective at stimulating spermatogenesis and increasing testicular size, but not effective at increasing testosterone concentrations in the leopard gecko between October-December in the Northern hemisphere.

A new species of leaf-toed gecko (Phyllodactylidae, Phyllodactylus) from María Cleofas Island, Nayarit, Mexico

We describe a new species of leaf-toed gecko of the genus Phyllodactylus from María Cleofas Island, the smallest island of Tres Marías Archipelago, Nayarit, México. Genomic, phylogenomic, and morphological evidence support that the new species presents a unique combination of diagnostic characters. Morphologically, the new species has a high number of tubercles, head to tail (mean 47), longitudinal ventral scales (mean 61), and third labial-snout scales (mean 26). Gene flow tests revealed the genetic isolation of insular populations from mainland counterparts. In addition, we confirmed the non-monophyly of P. homolepidurus and P. nolascoensis, and we show that the taxon P. t. saxatilis is a complex; therefore, we propose taxonomic changes within the saxatilis clade. The discovery of this new insular endemic species highlights the urgency of continued exploration of the biological diversity of island faunas of Mexico.