A review of the genus Garra Hamilton 1822 of Bhutan, including the descriptions of two new species and three additional records (Cypriniformes: Cyprinidae).

Seven species of Garra are herein accounted for in Bhutan. Three new records of known species, G. arupi, G. birostris, and G. lissorhynchus, and two new species, G. bimaculacauda sp. nov. and G. parastenorhynchus sp. nov., are reported from central and southern Bhutan. Garra bimaculacauda sp. nov. is most notably different from its congeners by the presence of two dark spots on the lobes of the caudal fin, having one spot on each lobe. Meristic and morphometric differences from northeastern Indian congeners exist as well. Garra parastenorhynchus sp. nov. is differentiated from its congeners by the presence of a prominent, overhanging, club-shaped proboscis, and a suite of meristic and morphometric characters. Notes on the taxonomy are provided for some species. Notes are provided on the biology and ecology for most species, which have been inferred from field observations. Ranges are expanded for two recently described taxa from Northeast India G. arupi, and G. birostris. A key is provided to the currently known species of Garra within Bhutan.

A new species of gravel-dwelling loach (Ostariophysi: Nemacheilidae) from the Nepalese Himalayan foothills.

Turcinoemacheilus himalaya, new species, is described from the Koshi and Gandaki River basins of Nepal. The new species is distinguished from its hypothesised congener, Turcinoemacheilus kosswigi, from the Euphrates, Tigris and Karoun basins of the Middle East, by the presence of small scales on the posterior half of its body (v. absence of all scales), its shorter caudal peduncle (caudal peduncle length 12-15% standard length, L(S) v. 16-23), its shorter snout (snout length 28-36% head length, L(H) v. 40-49) and by features of its colour pattern, including the presence of small irregularly shaped dark grey markings over the lateral body surface. Turcinoemacheilus himalaya is known to date only from Nepal.

Balitora eddsi, a new species of hillstream loach (Ostariophysi: Balitoridae) from Nepal.

A new species of hillstream loach Balitora eddsi is described from the Karnali River drainage in south-western Nepal. The new species is distinguished from all its congeners by possessing the following combination of characters: six to seven unbranched pectoral-fin rays, pelvic-fin length 12-14% standard length (L(S)), dorsal surface without circular or irregular shaped dark blotches, snout pointed, median lobe between anterior rostral barbels pointed posteriorly, dorsal-fin origin posterior to pelvic-fin origin, lateral line scales 66-67, caudal peduncle length 22-23.2% L(S), caudal peduncle depth 4.1-4.2 times its length.

Gill-filament ossifications: a possible morphological synapomorphy uniting the families Balitoridae and Cobitidae (Ostariophysi: Cypriniformes).

Ossifications associated with the gill filaments of members of the Balitoridae and Cobitidae are described for the first time. Although gill-filament ossifications are common in teleosts, similar ossifications were not observed in other members of the order Cypriniformes. Their presence is interpreted as a shared and derived character uniting the families Balitoridae and Cobitidae as a monophyletic group.

Molecular phylogeny of the Cobitoidea (Teleostei: Cypriniformes) revisited: position of enigmatic loach Ellopostoma resolved with six nuclear genes.

Molecular variation in six nuclear genes provides substantive phylogenetic evidence for the recognition of a new cypriniform family, the Ellopostomatidae, to include the enigmatic Southern Asia loach genus Ellopostoma. The current six loach families form a monophyletic group, with the Nemacheilidae as the sister group to Ellopostomatidae; Vaillantellidae forms the sister group to all families exclusive of Botiidae. While the superfamily Cobitoidea includes eight families, the monophyly of this large clade within the Cypriniformes remains a vexing problem despite extensive molecular analyses and is in need of further investigation.

Mitogenomic evolution and interrelationships of the Cypriniformes (Actinopterygii: Ostariophysi): the first evidence toward resolution of higher-level relationships of the world's largest freshwater fish clade based on 59 whole mitogenome sequences.

Fishes of the order Cypriniformes are almost completely restricted to freshwater bodies and number > 3400 species placed in 5 families, each with poorly defined subfamilies and/or tribes. The present study represents the first attempt toward resolution of the higher-level relationships of the world's largest freshwater-fish clade based on whole mitochondrial (mt) genome sequences from 53 cypriniforms (including 46 newly determined sequences) plus 6 outgroups. Unambiguously aligned, concatenated mt genome sequences (14,563 bp) were divided into 5 partitions (first, second, and third codon positions of the protein-coding genes, rRNA genes, and tRNA genes), and partitioned Bayesian analyses were conducted, with protein-coding genes being treated in 3 different manners (all positions included; third codon positions converted into purine [R] and pyrimidine [Y] [RY-coding]; third codon positions excluded). The resultant phylogenies strongly supported monophyly of the Cypriniformes as well as that of the families Cyprinidae, Catostomidae, and a clade comprising Balitoridae + Cobitidae, with the 2 latter loach families being reciprocally paraphyletic. Although all of the data sets yielded nearly identical tree topologies with regard to the shallower relationships, deeper relationships among the 4 major clades (the above 3 major clades plus Gyrinocheilidae, represented by a single species Gyrinocheilus aymonieri in this study), were incongruent depending on the data sets. Treatment of the rapidly saturated third codon-position transitions appeared to be a source of such incongruities, and we advocate that RY-coding, which takes only transversions into account, effectively removes this likely "noise" from the data set and avoids the apparent lack of signal by retaining all available positions in the data set.

Intraspecific phylogeography of Percina evides (Percidae: Etheostomatinae): an additional test of the Central Highlands pre-Pleistocene vicariance hypothesis.

North America exhibits the most diverse freshwater fish fauna among temperate regions of the world. Species diversity is concentrated in the Central Highlands, drained by the Mississippi, Gulf Slope and Atlantic Slope river systems. Previous investigations of Central Highlands biogeography have led to conflicting hypotheses involving dispersal and vicariance to explain the diversity and distribution of the freshwater fish fauna. In this investigation predictions of the Central Highlands pre-Pleistocene vicariance hypothesis are tested with a phylogeographic analysis of the percid species Percina evides, which is widely distributed in several disjunct areas of the Central Highlands. Phylogenetic analysis of complete gene sequences of mitochondrially encoded cytochrome b recover three phylogroups, with very low levels of sequence polymorphism within groups. The two western phylogroups are monophyletic with respect to the eastern phylogroup. The recovery of two monophyletic lineages with an eastern and western distribution in the disjunct highland areas is a pattern expected from vicariance, but is not predicted by the Central Highlands pre-Pleistocene vicariance hypothesis. The recovery of very limited mitochondrial DNA polymorphism and lack of phylogeographic structuring across the entire range of the eastern clade, very shallow polymorphism between the disjunct Missouri River and upper Mississippi River populations, and lack of sequence polymorphism in the upper Mississippi River populations, support a hypothesis of dispersal during or following the Pleistocene. The present distribution of P. evides is best explained by both vicariant and dispersal events.

Phylogenetic relationships of major clades of Catostomidae (Teleostei: Cypriniformes) as inferred from mitochondrial SSU and LSU rDNA sequences.

Suckers (Family Catostomidae) are holarctic in distribution and include 76 recent species in 14 genera, with 13 genera and 75 species occurring in North and Central America and Siberia. Although this group constitutes a significant component of many aquatic ecosystems, most historic systematic effort has been either alpha- or limited beta-level studies focusing on the two largest tribes within the family, the Catostomini and the Moxostomatini. A recent phylogenetic study based on morphological, biochemical, and early life history characters has advanced current understanding of relationships among catostomid fishes. To further examine phylogenetic relationships among basal lineages of catostomids, we sequenced the entire mitochondrial (mt) SSU and LSU rRNA genes from genera representing all subfamilies and tribes within Catostomidae. Phylogenetic analysis of gene sequences yielded monophyletic Catostomidae, Ictiobinae, and Catostominae and para- or polyphyletic Cycleptinae, with Myxocyprinus as the basal-most taxon and Cycleptus as either the next most-basal taxon or the taxon basal to the Catostominae. Relationships within the Catostominae were generally consistent with those proposed in the above-noted recent phylogenetic study although Thoburnia and Hypentelium were either a clade sister to or a grade group relative to Moxostoma and Scartomyzon. In all trees, Scartomyzon was paraphyletic and embedded within Moxostoma. Phylogenetic affinities of Erimyzon and Minytrema varied depending on data set and character weighting scheme employed. To better reflect phylogenetic relationships resolved in this extensive analysis, we propose the following changes to the classification of catostomids: formation of the new subfamily Myxocyprininae, containing Myxocyprinus from China; restriction of the Cycleptinae to the two species of Cycleptus from North America; restriction of the tribe Moxostomatini to Moxostoma and Scartomyzon; Erimyzon and Minytrema are incertae sedis within Catostominae; and resurrection of the tribe Thoburniini, containing Thoburnia and expanded to include Hypentelium.

Consilience and a hierarchy of species concepts: advances toward closure on the species puzzle.

Numerous concepts exist for biological species. This diversity of ideas derives from a number of sources ranging from investigative study of particular taxa and character sets to philosophical aptitude and world view to operationalism and nomenclatorial rules. While usually viewed as counterproductive, in reality these varied concepts can greatly enhance our efforts to discover and understand biological diversity. Moreover, this continued "turf war" and dilemma over species can be resolved if the various concepts are viewed in a hierarchical system and each evaluated for its inherent level of consilience. Under this paradigm a theoretically appropriate, highly consilient concept of species capable of colligating the abundant types of species diversity offers the best guidance for developing and employing secondary operational concepts for identifying diversity. Of all the concepts currently recognized, only the non-operational Evolutionary Species Concept corresponds to the requisite parameters and, therefore, should serve as the theoretical concept appropriate for the category Species. As operational concepts, the remaining ideas have been incompatible with one another in their ability to encompass species diversity because each has restrictive criteria as to what qualifies as a species. However, the operational concepts can complement one another and do serve a vital role under the Evolutionary Species Concept as fundamental tools necessary for discovering diversity compatible with the primary theoretical concept. Thus, the proposed hierarchical system of primary and secondary concepts promises both the most productive framework for mutual respect for varied concepts and the most efficient and effective means for revealing species diversity.

Phylogenetic relationships of the western North American phoxinins (Actinopterygii: Cyprinidae) as inferred from mitochondrial 12S and 16S ribosomal RNA sequences.

Parsimony analysis of the mitochondrial 12S and 16S rRNA sequences of North American phoxinin taxa indicated the existence of three major clades, the Western Clade, the Creek Chub Clade, and the Open Posterior Myodome Clade. The monophyletic Western Clade identified in this paper contained fewer taxa than that identified by previous authors. This clade contained species restricted to drainages west of the Continental Divide, such as Gila, Acrocheilus, Relictus, Eremichthys, Siphateles, Ptychocheilus, Lavinia, and Orthodon, and the wide-ranging genus Phoxinus found in eastern North America and Eurasia. Within this Western Clade Phoxinus was the basal sister group. Gila was recognized as a monophyletic group exclusive of Siphateles and Snyderichthys, clades traditionally recognized as subgenera of Gila. The genus Gila was most closely related to the genus Acrocheilus and together these formed the sister group to the genus Relictus. These relationships were supported independent of weighting schemes used in analyses. Identification of Phoxinus as the basal sister taxon of the Western clade implies that other major clades of North American Phoxinins likely have Asian or European relatives.

Phylogeny and biodiversity: Conserving our evolutionary legacy.

Historical ecological studies provide information about the origins of species in an area and the origins of traits characterizing the interactions between those species and their environment. Incorporating this evolutionary information into conservation policies will broaden the base of options for making effective decisions about the preservation of biodiversity.