Empirical and philosophical problems with the subspecies rank.

Species-level taxonomy derives from empirical sources (data and techniques) that assess the existence of spatiotemporal evolutionary lineages via various species "concepts." These concepts determine if observed lineages are independent given a particular methodology and ontology, which relates the metaphysical species concept to what "kind" of thing a species is in reality. Often, species concepts fail to link epistemology back to ontology.

Candidate-species delimitation in salamanders reveals gene flow across lineage boundaries, confounding phylogenetic estimation and clarifying hybrid zones.

Dusky Salamanders (genus ) currently comprise only 22 described, extant species. However, recent mitochondrial and nuclear estimates indicate the presence of up to 49 candidate species based on ecogeographic sampling. Previous studies also suggest a complex history of hybridization between these lineages.

Allometric escape from acoustic constraints is rare for frog calls.

Allometric constraint is a product of natural selection and physical laws, particularly with respect to body size and traits constrained by properties thereof, such as metabolism, longevity, and vocal frequency. Allometric relationships are often conserved across lineages, indicating that physical constraints dictate scaling patterns in deep time, despite substantial genetic and ecological divergence among organisms. In particular, acoustic allometry (sound frequency ~ body size) is conserved across frogs, in defiance of massive variation in both body size and frequency.

Further notes on the Sri Lankan uropeltid snakes Rhinophis saffragamus (Kelaart, 1853) and Uropeltis ruhunae Deraniyagala, 1954.

A recent paper dealing with the systematics of Uropeltidae (Pyron et al. 2016) made several taxonomic changes affecting Sri Lankan species in the genera Platyplectrurus Günther, 1868; Pseudotyphlops Schlegel, 1839; Rhinophis Hemprich, 1820; and Uropeltis Cuvier, 1829. Space precluded a full discussion of those changes, for which there was a wealth of additional photographs, data, and references.

Species sorting and mass effect along forest succession: Evidence from taxonomic, functional, and phylogenetic diversity of amphibian communities.

Species recovery after forest disturbance is a highly studied topic in the tropics, but considerable debate remains on the role of secondary forests as biodiversity repositories, especially regarding the functional and phylogenetic dimensions of biodiversity. Also, studies generally overlook how alpha and beta diversities interact to produce gamma diversity along successional gradients.We used a metacommunity approach to assess how species sorting (i.

A new ancient lineage of frog (Anura: Nyctibatrachidae: Astrobatrachinae subfam. nov.) endemic to the Western Ghats of Peninsular India.

The Western Ghats (WG) is an escarpment on the west coast of Peninsular India, housing one of the richest assemblages of frogs in the world, with three endemic families. Here, we report the discovery of a new ancient lineage from a high-elevation massif in the Wayanad Plateau of the southern WG. Phylogenetic analysis reveals that the lineage belongs to Natatanura and clusters with Nyctibatrachidae, a family endemic to the WG/Sri Lanka biodiversity hotspot.

Genomic timetree and historical biogeography of Caribbean island ameiva lizards (: Teiidae).

The phylogenetic relationships and biogeographic history of Caribbean island ameivas () are not well-known because of incomplete sampling, conflicting datasets, and poor support for many clades. Here, we use phylogenomic and mitochondrial DNA datasets to reconstruct a well-supported phylogeny and assess historical colonization patterns in the group. We obtained sequence data from 316 nuclear loci and one mitochondrial marker for 16 of 19 extant species of the Caribbean endemic genus .

Fossil-based comparative analyses reveal ancient marine ancestry erased by extinction in ray-finned fishes.

The marine-freshwater boundary is a major biodiversity gradient and few groups have colonised both systems successfully. Fishes have transitioned between habitats repeatedly, diversifying in rivers, lakes and oceans over evolutionary time. However, their history of habitat colonisation and diversification is unclear based on available fossil and phylogenetic data.

Systematics of the blindsnakes (Serpentes: Scolecophidia: Typhlopoidea) based on molecular and morphological evidence.

The blindsnake superfamily Typhlopoidea (Gerrhopilidae, Typhlopidae, and Xenotyphlopidae) is a diverse, widespread part of the global snake fauna. A recent systematic revision based on molecular phylogenetic analyses and some morphological evidence presented a preliminary solution to the non-monophyly of many previously recognized genera, but additional clarification is needed regarding the recognition of some species and genera. We rectify these problems here with a new molecular phylogenetic analysis including 95 of the 275 currently recognized, extant typhlopoids, incorporating both nuclear and mitochondrial loci.

Phylogenetic analyses reveal unexpected patterns in the evolution of reproductive modes in frogs.

Understanding phenotypic diversity requires not only identification of selective factors that favor origins of derived states, but also factors that favor retention of primitive states. Anurans (frogs and toads) exhibit a remarkable diversity of reproductive modes that is unique among terrestrial vertebrates. Here, we analyze the evolution of these modes, using comparative methods on a phylogeny and matched life-history database of 720 species, including most families and modes.