The Terrific Skink bite force suggests insularity as a likely driver to exceptional resource use.

Natural history museum collections hold extremely rare, extinct species often described from a single known specimen. On occasions, rediscoveries open new opportunities to understand selective forces acting on phenotypic traits. Recent rediscovery of few individuals of Bocourt´s Terrific Skink Phoboscincus bocourti, from a small and remote islet in New Caledonia allowed to genetically identify a species of land crab in its diet. To explore this further, we CT- and MRI-scanned the head of the holotype, the only preserved specimen dated to about 1870, segmented the adductor muscles of the jaw and bones, and estimated bite force through biomechanical models. These data were compared with those gathered for 332 specimens belonging to 44 other skink species. Thereafter we recorded the maximum force needed to generate mechanical failure of the exoskeleton of a crab specimen. The bite force is greater than the prey hardness, suggesting that predation on hard-shelled crabs may be an important driver of performance. The high bite force seems crucial to overcome low or seasonal variations in resource availability in these extreme insular environments. Phoboscincus bocourti appears to be an apex predator in a remote and harsh environment and the only skink known to predate on hard-shelled land crabs.

A new species of Erythrolamprus from the oceanic island of Tobago (Squamata, Dipsadidae).

Tobago is a small island on the southeast edge of the Caribbean Plate with a continental flora and fauna. Using DNA sequences from Genbank, new sequences, and morphological data from the snakes Erythrolamprusepinephalus, E.melanotus, E.reginae, and E.zweifeli, the species status of specimens of a Tobago snake previously considered to be Erythrolamprusreginae was assessed. Erythrolampruszweifeli, long considered a subspecies of E.reginae, was found to be a northern Venezuela-Trinidad endemic and the sister to E.reginae. The trans-Andean species E.epinephalus is shown to be non-monophyletic while the Costa Rican lineage of E.epinephalus is weakly supported as the sister to the Tobago population. The Tobago Erythrolamprus is described as a distinct taxon based upon five specimens from four localities in lower montane rainforest. Much of the new species range includes the Main Ridge Forest Reserve of Tobago, the oldest protected forest in the Western Hemisphere. All known locations fall within a 400-ha area, and its total geographic distribution is likely to be less than 4,566 ha. The restricted distribution of this new snake makes it a likely candidate for threatened status. The new species also becomes another biogeographic link between northern Venezuela and Tobago.

Peptidomic analysis of the host-defense peptides in skin secretions of the Trinidadian leaf frog Phyllomedusa trinitatis (Phyllomedusidae).

Peptidomic analysis (reversed-phase HPLC combined with MALDI-TOF mass spectrometry and automated Edman degradation) of norepinephrine-stimulated skin secretions from the Trinidadian leaf frog Phyllomedusa trinitatis Mertens 1926 led to the identification and structural characterization of 26 host-defense peptides. On the basis of amino acid sequence similarity, the peptides may be divided into the followings groups: dermaseptins with the conserved N-terminal region GLWSKIK (6 peptides), dermaseptins with the N-terminal region ALWKXXLK (5 peptides), dermaseptins with the conserved N-terminal region GLFKTLIKGAGKMLGHVAK (4 peptides), C-terminally α-amidated and non-amidated forms of the phylloseptins (9 peptides), phyllocaerulein, a peptide (GLVSGLLNSVTGLLGNLAGGGL) with structural similarity to the plasticins, and a putative antioxidant peptide (LTWKIPTRFCGVT). The primary structures of the peptides support the claim based upon morphological criteria that P. trinitatis and Phyllomedusa tarsius are very closely related phylogenetically but are probably not conspecific. Among the phylloseptins, phylloseptin-1.1TR (FLSLIPKIAGGIASLVKNL.NH2) displayed the most potent antimicrobial activity.