Thermal niche evolution and geographical range expansion in a species complex of western Mediterranean diving beetles

[Background] Species thermal requirements are one of the principal determinants of their ecology and biogeography, although our understanding of the interplay between these factors is limited by the paucity of integrative empirical studies. Here we use empirically collected thermal tolerance data in combination with molecular phylogenetics/phylogeography and ecological niche modelling to study the evolution of a clade of three western Mediterranean diving beetles, the Agabus brunneus complex.[Results] The preferred mitochondrial DNA topology recovered A. ramblae (North Africa, east Iberia and Balearic islands) as paraphyletic, with A. brunneus (widespread in the southwestern Mediterranean) and A. rufulus (Corsica and Sardinia) nested within it, with an estimated origin between 0.60-0.25 Ma. All three species were, however, recovered as monophyletic using nuclear DNA markers. A Bayesian skyline plot suggested demographic expansion in the clade at the onset of the last glacial cycle. The species thermal tolerances differ significantly, with A. brunneus able to tolerate lower temperatures than the other taxa. The climatic niche of the three species also differs, with A. ramblae occupying more arid and seasonal areas, with a higher minimum temperature in the coldest month. The estimated potential distribution for both A. brunneus and A. ramblae was most restricted in the last interglacial, becoming increasingly wider through the last glacial and the Holocene.[Conclusions] The A. brunneus complex diversified in the late Pleistocene, most likely in south Iberia after colonization from Morocco. Insular forms did not differentiate substantially in morphology or ecology, but A. brunneus evolved a wider tolerance to cold, which appeared to have facilitated its geographic expansion. Both A. brunneus and A. ramblae expanded their ranges during the last glacial, although they have not occupied areas beyond their LGM potential distribution except for isolated populations of A. brunneus in France and England. On the islands and possibly Tunisia secondary contact between A. brunneus and A. ramblae or A. rufulus has resulted in introgression. Our work highlights the complex dynamics of speciation and range expansions within southern areas during the last glacial cycle, and points to the often neglected role of North Africa as a source of European biodiversity.This work was supported by an FPI grant to AH-G and projects CGL2007-61665 and CGL2010-15755 from the Spanish government to IR. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe

Geographic variation in the zone of contact between two subspecies of gopher snakes Pituophis melanoleucus

Abstract not availabl

A new species of Riama from Ecuador previously referred to as Riama hyposticta (Boulenger, 1902) (Squamata, Gymnophthalmidae). (American Museum novitates, no. 3719)

16 p. : ill. (chiefly col.), map. "June 3, 2011."We describe Riama crypta, new species, from the western slopes of the Cordillera Occidental, Ecuador. This taxon was formerly referred to as Riama hyposticta, a rare species described on the basis of an adult male from northern Ecuador and here recorded from southwestern Colombia. The new species differs principally from Riama hyposticta by an incomplete superciliary series, formed just by the anteriormost superciliary scale (superciliary series complete in R. hyposticta, formed by five or six scales), no nasoloreal suture (= loreal absent) (complete (= loreal present) in R. hyposticta), distinct dorsolateral stripes at least anteriorly (scattered brown spots dorsally without dorsolateral stripes in R. hyposticta), and ventral coloration composed of small cream or brown spots or longitudinal stripes (dark brown with conspicuous transverse white bars and spots). Additionally, we document the presence of distal filiform appendages on the hemipenial lobes of both species

A New Species of Riama from Ecuador Previously Referred to as Riama hyposticta (Boulenger, 1902) (Squamata: Gymnophthalmidae)

We describe Riama crypta, new species, from the western slopes of the Cordillera Occidental, Ecuador. This taxon was formerly referred to as Riama hyposticta, a rare species described on the basis of an adult male from northern Ecuador and here recorded from southwestern Colombia. The new species differs principally from Riama hyposticta by an incomplete superciliary series, formed just by the anteriormost superciliary scale (superciliary series complete in R. hyposticta, formed by five or six scales), no nasoloreal suture [= loreal absent] (complete (= loreal present] in R. hyposticta), distinct dorsolateral stripes at least anteriorly (scattered brown spots dorsally without dorsolateral stripes in R. hyposticta), and ventral coloration composed of small cream or brown spots or longitudinal stripes (dark brown with conspicuous transverse white bars and spots). Additionally, we document the presence of distal filiform appendages on the hemipenial lobes of both species.American Museum of Natural HistoryCoordenadoria de Aperfeicoamento de Pessoal de Ensino Superior (CAPES)Programa de Becas para la Iniciativa de Especies Amenazadas IEA[520]Fundacao de Amparo a Pesquisa do Estado de sao Paulo (FAPESP)[2007/00811-8

Hebius paraphyly.

7 pages : 1 illustration ; 26 cm.We investigate the phylogenetic relationships of two poorly known Natricinae, Parahelicops and Pararhabdophis, for which we obtained nucleotide sequence data from one mitochondrial gene (cytochrome b) and three nuclear genes (CMOS, NT3, and RAG1). Maximum parsimony, maximum likelihood, and combined and partitioned Bayesian analyses suggest that both Parahelicops and Pararhabdophis are embedded within the genus Hebius. To align classification with phylogeny, we synonymize Parahelicops and Pararhabdophis with Hebius

FIGURE 2 in A new Petracola and re-description of P. ventrimaculatus (Squamata: Gymnophthalmidae)

FIGURE 2. Dorsal (A), lateral (B), and ventral (C) views of the head of the holotype of Petracola waka sp. nov.. Line equals 1 mm

Parahelicops, Pararhabdophis, paraphyly : phylogenetic relationships among certain Southeast Asian natricine snakes (Hebius)

no. 390