Species of Garra (Cyprinidae: Labeoninae) in the Salween River basin with description of an enigmatic new species from the Ataran River drainage of Thailand and Myanmar.

Garra panitvongi, new species, is described from the Ataran River drainage, Salween River basin, of southeastern Myanmar and western Thailand. It is the sixth species of Garra known from the Salween River basin and is readily distinguished from all congeners by the red-orange color of the body and caudal fin, and a pointed proboscis with a blue stripe on each side from the anterior margin of the orbit to the tip of the proboscis and with the stripes forming a V-shape. Garra panitvongi is known in the aquarium trade as the Redtail Garra. Descriptive information is provided on poorly known species of Garra in the Salween River basin, and Garra nujiangensis is transferred to Ageneiogarra.

Review of the spotted lizard loaches, Pseudohomaloptera (Cypriniformes: Balitoridae) with a re-description of Pseudohomaloptera sexmaculata and description of a new species from Sumatra.

A review of the six recognized species of Pseudohomaloptera is provided. Counts in the original description of Pseudohomaloptera sexmaculata Fowler (1934) were incorrect and led to confusion in identifying populations of Pseudohomaloptera in mainland Southeast Asia, and the species is re-described. The validity of Homaloptera septemmaculata Fowler (1934) is investigated and confirmed as a junior synonym of P. sexmaculata. P. sexmaculata and Pseudohomaloptera leonardi, similar morphologically and often misidentified, are widely distributed in mainland Southeast Asia, with P. sexmaculata in the Chao Phraya, Mae Klong and Pran Buri River basins, and P. leonardi in the Malay Peninsula and the Chao Phraya and Mekong River basins. Pseudohomaloptera yunnanensis and Pseudohomaloptera vulgaris have been reported from the Mekong basin of Thailand and Laos but appear to be restricted to Yunnan Province, China. A new species of Pseudohomaloptera is described from Sumatra. This is the southern-most species and first record for the genus from the Indonesian island. An identification key is provided for all species of the genus.

Genomic Organization of Repetitive DNA Elements and Extensive Karyotype Diversity of Silurid Catfishes (Teleostei: Siluriformes): A Comparative Cytogenetic Approach.

The catfish family Siluridae contains 107 described species distributed in Asia, but with some distributed in Europe. In this study, karyotypes and other chromosomal characteristics of 15 species from eight genera were examined using conventional and molecular cytogenetic protocols. Our results showed the diploid number (2n) to be highly divergent among species, ranging from 2n = 40 to 92, with the modal frequency comprising 56 to 64 chromosomes. Accordingly, the ratio of uni- and bi-armed chromosomes is also highly variable, thus suggesting extensive chromosomal rearrangements. Only one chromosome pair bearing major rDNA sites occurs in most species, except for Wallago micropogon, Ompok siluroides, and Kryptoterus giminus with two; and Silurichthys phaiosoma with five such pairs. In contrast, chromosomes bearing 5S rDNA sites range from one to as high as nine pairs among the species. Comparative genomic hybridization (CGH) experiments evidenced large genomic divergence, even between congeneric species. As a whole, we conclude that karyotype features and chromosomal diversity of the silurid catfishes are unusually extensive, but parallel some other catfish lineages and primary freshwater fish groups, thus making silurids an important model for investigating the evolutionary dynamics of fish chromosomes.