Allen Allison

Ecological Guild Evolution and the Discovery of the World's Smallest Vertebrate

Living vertebrates vary drastically in body size, yet few taxa reach the extremely minute size of some frogs and teleost fish. Here we describe two new species of diminutive terrestrial frogs from the megadiverse hotspot island of New Guinea, one of which represents the smallest known vertebrate species, attaining an average body size of only 7.7 mm. Both new species are members of the recently described genus Paedophryne, the four species of which are all among the ten smallest known frog species, making Paedophryne the most diminutive genus of anurans. This discovery highlights intriguing ecological similarities among the numerous independent origins of diminutive anurans, suggesting that minute frogs are not mere oddities, but represent a previously unrecognized ecological guild.

The global distribution of tetrapods reveals a need for targeted reptile conservation

The distributions of amphibians, birds and mammals have underpinned global and local conservation priorities, and have been fundamental to our understanding of the determinants of global biodiversity. In contrast, the global distributions of reptiles, representing a third of terrestrial vertebrate diversity, have been unavailable. This prevented the incorporation of reptiles into conservation planning and biased our understanding of the underlying processes governing global vertebrate biodiversity. Here, we present and analyse the global distribution of 10,064 reptile species (99% of extant terrestrial species). We show that richness patterns of the other three tetrapod classes are good spatial surrogates for species richness of all reptiles combined and of snakes, but characterize diversity patterns of lizards and turtles poorly. Hotspots of total and endemic lizard richness overlap very little with those of other taxa. Moreover, existing protected areas, sites of biodiversity significance and global conservation schemes represent birds and mammals better than reptiles. We show that additional conservation actions are needed to effectively protect reptiles, particularly lizards and turtles. Adding reptile knowledge to a global complementarity conservation priority scheme identifies many locations that consequently become important. Notably, investing resources in some of the world’s arid, grassland and savannah habitats might be necessary to represent all terrestrial vertebrates efficiently.The global distribution of nearly all extant reptile species reveals richness patterns that differ spatially from that of other taxa. Conservation prioritization should specifically consider reptile distributions, particularly lizards and turtles.

Uncovering cryptic diversity in Aspidomorphus (Serpentes: Elapidae): Evidence from mitochondrial and nuclear markers

The Papuan region, comprising New Guinea and nearby islands, has a complex geological history that has fostered high levels of biodiversity and endemism. Unfortunately, much of this diversity remains undocumented. We examine the evolutionary relationships of the venomous snake genus Aspidomorphus (Elapidae: Hydrophiinae), a Papuan endemic, and document extensive cryptic lineage diversification. Between Aspidomorphus species we find 22.2-27.9% corrected cyt-b sequence divergence. Within species we find 17.7-23.7% maximum sequence divergence. These high levels of genetic divergence may have complicated previous phylogenetic studies, which have had difficulty placing Aspidomorphus within the subfamily Hydrophiinae. Compared to previous studies, we increase sampling within Hydrophiinae to include all currently recognized species of Aspidomorphus and increase species representation for the genera Demansia and Toxicocalamus. We confirm monophyly of Aspidomorphus and resolve placement of the genus utilizing a set of seven molecular markers (12S, 16S, cyt-b, ND4, c-mos, MyHC-2, and RAG-1); we find strong support for a sister-group relationship between Aspidomorphus and a Demansia/Toxicocalamus preussi clade. We also use one mitochondrial (cyt-b) and one nuclear marker (SPTBN1) to document deep genetic divergence within all currently recognized species of Aspidomorphus and discuss the Solomon Island Arc as a potential center of divergence in this species. Lastly, we find high levels of concordance between the mtDNA and nuDNA markers used for inter-species phylogenetic reconstruction.

A Remarkable Ontogenetic Change in Color Pattern in a New Species of Oreophryne (Anura: Microhylidae) from Papua New Guinea

Abstract We describe a new species of scandent/arboreal frog from Sudest Island, Louisiade Archipelago, off the southeastern tip of New Guinea that exhibits a remarkable ontogenetic change in color pattern. Juveniles are shiny black with lemon-yellow spots; adults are uniform peach with bright blue eyes. We detail the ontogenetic changes in color-pattern elements that comprise this transformation. This ontogenetic change, uniform peach adult coloration, and blue iris all appear to be unique features within the genus Oreophryne, most of whose members are tan, brown, or gray. We presume the striking juvenile color pattern to serve an aposematic function, but this conjecture requires testing. The new species is restricted to a relatively small patch of cloud forest perched on the highest peak of Sudest Island. Climate change may pose a threat to the new species if changing rainfall or temperature regimes result in the loss of this forest.

New Species of Platymantis (Anura: Ranidae) from New Ireland

Abstract We describe a new species of Platymantis from the Weitin River Valley on the southern tip of New Ireland in the southwest Pacific, bringing to seven the number of native frogs known from that island. We also briefly report on the ecology of the four species of Platymantis occurring on New Ireland and comment on the biogeography of the frog fauna.

Two New Species of Cophixalus from New Guinea

We describe two new species of Cophixalus from the north coast ranges of Papua New Guin- ea. One of the species has a reduced first finger lacking a disc and is clearly aligned with C. shellyi, C. ateles, and C. pipilans. The other species also has a reduced first finger but retains a disc on that digit. Its relationships within the genus are less clear but are probably also with the clade having a reduced first

A Colorful New Species of Albericus (Anura: Microhylidae) from Southeastern Papua New Guinea

ABSTRACT We describe a new species of Albericus from the northern slope of Mt. Simpson, in the Owen Stanley Range of southeastern Papua New Guinea. The new species differs from all other known species of the genus in having pale blue or pale green dorsal coloration with red punctations (light metallic green and burnt orange in preservative). It is further distinguished from its congeners in its combination of oblique lores, granular skin with a few tubercles, broad head, large distance separating the external nares from the eyes, and in features of its call. We also provide comparative morphological measurements for most other species of Albericus to supplement the paucity of such data in original descriptions and to assist with future diagnoses of other new species.

Evolutionary relationships among 12 species belonging to three genera of the family Microhylidae in Papua New Guinea revealed by allozyme analysis

To elucidate the potential of electrophoretic analysis for understanding relationships among microhylid frogs in Papua New Guinea, an allozyme analysis was conducted. A total of 119 individuals from nine species of Cophixalus, two species of Sphenophryne and one species of Barygenys, all of which belong to the family Microhylidae, were studied. Fourteen enzymes extracted from skeletal muscles and livers were analyzed by starch-gel electrophoresis. These enzymes were encoded by genes at 20 loci. There were 2-15 phenotypes produced by 2-12 alleles at these loci. The mean proportion of heterozygous loci per individual, mean proportion of polymorphic loci per population, and mean number of alleles per locus in 12 species were 6.1%, 17.1% and 1.17a on average, respectively. The NJ and ML trees constructed from Neis genetic distances showed that the genus Sphenophryne can be distinguished biochemically from Cophixalus and Barygenys, and that the species groups of Cophixalus, which are similar in external morphology, can be divided biochemically into several species.

New Species of Albericus (Anura: Microhylidae) from Eastern New Guinea

Abstract We describe a new species of Albericus from Mt. Shungol in the Herzog Mountains at the north end of the Owen Stanley terrane of Papua New Guinea. The new species differs from all other known species of the genus in its rapid peeping call and in having the tympana hidden in males. It can be further distinguished from particular congeners in a variety of morphometric variables. The new species inhabits lowland hill forest, was moderately common where found, and is only known from the slopes of Mt. Shungol.

A New Species of Callulops (Anura: Microhylidae) from Papua New Guinea

We describe a new species of Callulops from the vicinity of Crater Mountain Biological Station in south-central Papua New Guinea. The species may be distinguished from its congeners by its unique dorsal color pattern, moderately expanded digital disks bearing circummarginal grooves, smooth skin, relatively long legs, and relatively short snout. The species is currently known only from the type locality, and its nearest relatives remain obscure.