One-quarter of freshwater fauna threatened with extinction.

Freshwater ecosystems are highly biodiverse and important for livelihoods and economic development, but are under substantial stress. To date, comprehensive global assessments of extinction risk have not included any speciose groups primarily living in freshwaters. Consequently, data from predominantly terrestrial tetrapods are used to guide environmental policy and conservation prioritization, whereas recent proposals for target setting in freshwaters use abiotic factors.

Silurichthys exortivus, a new catfish (Teleostei: Siluridae) from eastern Borneo, Indonesia.

Silurichthys exortivus, a new species of silurid catfish, is described from the Mahakam River drainage in eastern Borneo. The new species can be distinguished from congeners in lacking a dorsal fin, having 4 (vs. 67) principal rays on the upper caudal-fin lobe and a combination of: body depth at anus 14.

Pseudobagarius eustictus, a new species of catfish from northern Laos (Siluriformes: Akysidae).

Pseudobagarius eustictus, new species, is described from the Nam Heung drainage (a tributary of the Mekong River) in northern Laos. It is distinguished from congeners in having a unique combination of the following characters: a weakly-produced snout in which the upper jaw extends only slightly beyond the margin of the lower jaw when viewed ventrally, 3 tubercles on the posterior margin of the pectoral spine, eye diameter 8% HL, head width 24.1% SL, dark yellow dorsal and lateral surfaces of the head, pectoral spine lacking elongate extensions, pectoral fin reaching the pelvic-fin base when adpressed against the body, dorsolateral surfaces of body without longitudinal series of prominent tubercles, body depth at anus 13.

Description of Bagarius vegrandis, a new species of sisorid catfish from Indochina (Actinopterygii: Siluriformes), with notes on the identity of Bagarius bagarius.

Bagarius vegrandis, new species, is described from the Chao Phraya and Mekong river drainages. It differs from congeners in having a small maximum body size (to 220 mm SL vs. 520-1400 mm SL) and the adipose-fin origin markedly posterior to (vs.

A new, uniquely patterned spiny eel (Teleostei: Mastacembelidae) from southern Borneo, Kalimantan Tengah, Indonesia.

A new species of Macrognathus of the M. aculeatus species group is described from the Kahayan River drainage in southern Borneo, Kalimantan Tengah, Indonesia. Macrognathus kris, new species, is distinguished from all Asian congeners in having the following unique combination of characters: rim of anterior nostril with two fimbriae and two fimbrules; 43-45 rostral tooth plates; 24-25 dorsal spines; 46-55 dorsal-fin rays; 51-59 anal-fin rays; 20-23 principal caudal-fin rays; 76-78 total vertebrae; body depth at anus 11.

Leiocassis rudicula (Teleostei: Siluriformes: Bagridae), a new catfish from eastern Borneo.

A new species of bagrid catfish in the genus Leiocassis is described from the Mahakam River drainage in eastern Borneo. Leiocassis rudicula, new species, can be distinguished from congeners in having a unique combination of: distinct concavity at level of orbit in dorsolateral profile of head; tip of supraoccipital spine not reaching anterior nuchal plate element; smooth posterior margin of dorsal spine; presence of an irregular pale band on sides of body between dorsal and adipose fins; anal fin with narrow brown band across middle third of fin; narrow caudal-fin lobes with nearly straight posterior margins; snout length 36-40% HL; eye diameter 14-20% HL; head depth 17.6-20.

Pterocryptis subrisa, a new silurid catfish (Teleostei: Siluridae) from northeastern India.

Pterocryptis subrisa, a new species of silurid catfish from the Kaladan River drainage in northeastern India, is described in this study. It can be distinguished from congeners by the unique combination of the following characters: supralabial fold extending posteriorly beyond vertical through posterior orbital margin; nearly circular eye; head length 17.6-19.

Exostoma ericinum, a new glyptosternine catfish from southwestern China (Teleostei: Siluriformes: Sisoridae).

A new species of glyptosternine catfish in the genus Exostoma is described in this study. The new species, E. ericinum, is known from the upper Dayingjiang (=Taping River) drainage in southwestern China and is distinguished from congeners in having an unique combination of the following characters: 42-44 vertebrae; parallel striae on anterolateral surfaces of lips and lower surface of maxillary barbel; interorbital distance 26-31% HL; preanal length 67.

The of the Bolaven Plateau, Laos (Teleostei: Sisoridae): new and endangered.

Glyptothorax forabilis, new species, and G. porrectus, new species, are described from the Bolaven Plateau in southern Laos. Both species closely resemble G.

The of Sundaland: a revisionary study (Teleostei: Sisoridae).

The species of Glyptothorax of Sundaic Southeast Asia (Malay Peninsula, Sumatra, Borneo and Java) are revised in this study. A total of 17 species are recognized, of which six (G. amnestus, G.

A new species of anguilliform catfish (Actinopterygii: Siluriformes: Bagridae) from Bangladesh and northeastern India.

We describe Olyra praestigiosa, a new anguilliform bagrid catfish, from the Brahmaputra River drainage in Bangladesh and northeastern India. The new species differs from congeners in having the following unique combination of characters: interorbital distance 30-37% HL; body depth at anus 6-9% SL; length of adipose-fin base 99-16% SL; adipose fin separate from upper principal caudal-fin rays; post-adipose distance 15-18% SL; 17-22 anal-fin rays; caudal peduncle length 14-19% SL; and caudal peduncle depth 6-8% SL.

A new diminutive sisorid catfish (Actinopterygii: Siluriformes) from northeastern India.

This study describes a new diminutive sisorid catfish from the upper reaches of the Karnaphuli River drainage in northeastern India. The new species can be distinguished from congeners in having a combination of: length of dorsal-fin spine 18.0-21.

Clarias serniosus, a new walking catfish (Teleostei: Clariidae) from Laos.

Clarias serniosus, a new Southeast Asian walking-catfish species, is described from the Bolavens Plateau in southern Laos. The new species is a member of the C. batrachus species complex, and can be distinguished from congeners in the complex in having a combination of: occipital process length 15-17 % HL, head length 28.

A review of the glyptosternine catfish genus Exostoma Blyth 1860 from Thailand, with descriptions of two new species (Teleostei: Siluriformes).

We review members of the sisorid catfish genus Exostoma known from Thailand. Three species are recognized, of which two from the headwaters of the Chao Phraya River drainage in northwestern Thailand, are described here as new: E. effrenum and E.

Olyra saginata, a new species of bagrid catfish (Actinopterygii: Siluriformes) from northeastern India.

Olyra saginata, new species, is described from the Kaladan [=Kolodyne] River system in Mizoram, northeast India. It differs from congeners in having the following unique combination of characters: interorbital distance 27.9-35.

On Psilorhynchus sucatio and P. nudithoracicus, with the description of a new species of Psilorhynchus from northeastern India (Ostariophysi: Psilorhynchidae).

Psilorhynchus sucatio (Hamilton) is redescribed based on the examination of 462 specimens, 13-67 mm standard length (SL). Psilorhynchus nudithoracicus Tilak & Husain is redescribed based on the examination of 97 specimens, 10-68 mm SL. Psilorhynchus gracilis Rainboth is placed in the synonymy of P nudithoracicus.

Ompok karunkodu, a new catfish (Teleostei: Siluridae) from southern India.

Ompok karunkodu, a new species of silurid catfish is described from the Amaravathi River, a right-hand tributary of the Kaveri [=Cauvery] River in Tamil Nadu, southern India. Ompok karunkodu can be distinguished from all congeners in the Indian subcontinent in having a markedly convex predorsal profile (vs. with a slight or distinct concavity in the supraethmoidal or supraoccipital region), and a unique combination of the following characters: prognathous lower jaw causing anterior profile of head to appear rounded when viewed laterally, maxillary barbel reaching to base of pectoral-fin spine, eye diameter 13.

Pseudolaguvia nubila, a new sisorid catfish (Teleostei: Sisoridae) from northeastern India.

This study describes Pseudolaguvia nubila, a new miniature sisorid catfish from the Kaladan River drainage in northeastern India. Pseudolaguvia nubila can be distinguished from congeners in having a combination of a mottled brown body with yellowish bands, a weakly projecting snout in which the premaxillary teeth are barely exposed when the mouth is closed, head width 19.7-21.

After eighty years of misidentification, a name for the glass catfish (Teleostei: Siluridae).

We resolve the identity of the glass catfish, a species of Asian freshwater fish commonly encountered as an ornamental fish and an experimental subject that has long been misidentified as either Kryptopterus bicirrhis or K. minor. Our study indicates that the glass catfish is an unnamed species distinct from either, which we describe here as Kryptopterus vitreolus.

Glyptothorax radiolus, a new species of sisorid catfish (Osteichthyes: Siluriformes) from northeastern India, with a redescription of G. striatus McClelland 1842.

Glyptothorax radiolus, new species, is described from the Brahmaputra River drainage in West Bengal, northeast India. It differs from most congeners in the Indian subcontinent in possessing plicae on the ventral surfaces of the pectoral spine and first pelvic-fin ray. The following combination of characters serve to distinguish it from congeners in the Indian subcontinent with plicate ventral surfaces of the pectoral spine and first pelvic-fin ray: eye diameter 6.

Glyptothorax igniculus, a new species of sisorid catfish (Teleostei: Siluriformes) from Myanmar.

Glyptothorax igniculus, new species, is described from the Chindwin River system (part of the Irrawaddy River drainage) in northwestern Myanmar. It differs from other species of Glyptothorax in the Irrawaddy drainage except G. burmanicus in having a thoracic adhesive apparatus with a lanceolate central depression that is nearly enclosed posteriorly by skin ridges, vs.

Monophyly and phylogenetic relationships of the catfish genus Glyptothorax (Teleostei: Sisoridae) inferred from nuclear and mitochondrial gene sequences.

Glyptothorax Blyth (1860) is the most species-diverse and widely-distributed genus in the Sisoridae, but few studies have examined monophyly of the genus and phylogenetic relations within it. We used the nuclear RAG2 gene and mitochondrial COI and Cyt b genes from 50 of the approximately 70 species to examine monophyly of Glyptothorax and phylogenetic relationships within the genus. Molecular phylogenetic trees were constructed using maximum parsimony, maximum likelihood and Bayesian inference methods.