A review of the catfish genus Pterocryptis (Siluridae) in Vietnam, with the description of two new species

Of the silurid catfish genus Pterocryptis in Vietnam, a total of four species are recognized as valid, of which Pterocryptis crenula and P. verecunda are described here as new. The type locality of P. cochinchinensis is restricted to central Vietnam, and the species is redescribed from topotypic material. Pterocryptis crenula (from northeastern Vietnam) can be differentiated from its congeners in having visibly confluent anal and caudal fins while P. verecunda (from Cat Ba Island in northeastern Vietnam) can be differentiated from its congeners in having the genital papilla concealed behind the anus. Notes on the identity of other nominal Pterocryptis species are also provided.     

A revision of the South-east Asian catfish genus Silurichthys

The taxonomy of the catfish genus Silurichthys is revised, and eight species are now recognized. A neotype is designated for S. hasseltii . Two new species are described: S. gibbiceps from the Barito basin in southern Borneo and S. marmoratus from north-western Borneo. Silurichthys leucopodus Fowler, 1939, is considered a subjective junior synonym of S. schneideri Volz, 1904. The extent of the gape and the relative positions of the dorsal and pelvic fins show considerable infraspecific variation and are of little taxonomic value. The number of anal-fin rays is useful if used with other meristic data such as the number of vertebrae. Colour varies infraspecifically as individuals become paler and less mottled at night, but can still be used as a secondary character in separating some species. The head and caudal fin shapes are useful discriminating characters. Mature males are smaller than females and have prominent posterior serrae on the pectoral spine and articulated segments of the first pectoral-fin element. The shape and number of these serrae are also diagnostic for some species.     

A review of the Ompok hypophthalmus group of silurid catfishes with the description of a new species from South-East Asia

The identities of the nominal species in the Ompok hypophthalmus group of silurid catfishes, namely Ompok hypophthalmus , O. macronema and O. urbaini are verified in this study. Ompok macronema is hypothesized to be a junior synonym of O. hypophthalmus , and O. urbaini (previously considered a junior synonym of O. hypophthalmus ) is hypothesized to be valid, distinct species. Ompok hypophthalmus is restricted to Java and the Barito River drainage in southern Borneo, and the material previously identified as O. hypophthalmus from Sumatra, the Malay Peninsula and Borneo represents O. rhadinurus , a new species.     

Fossil record of a silurid catfish from the Middle Miocene Sanuki Group of Ohkawa, Kagawa Prefecture, Japan

A fossil specimen identified as a silurid catfish (92.5 mm SL) was collected from the Middle Miocene Sanuki Group (15.8±0.9 Ma) of Ohkawa, Kagawa Prefecture, Japan. This is the oldest certain record of a silurid catfish. Morphological characteristics of the specimen are as follows: 52 or 53 vertebrae, 61 or 62 anal fin rays, a stout, short spine (11%SL) and 10 or more soft rays of the pectoral fin, 8 or more pelvic fin rays, 8 or more branchiostegal rays, head length of ca. 24%SL, and most probably not forked caudal fin. The fossil specimen is clearly distinct from three extant silurids in Japan, and probably belongs to an undescribed form considering its geological age.     

广西鲇属一新种及其性状讨论(鲇形目,鲇科)

根据采自广西都安县的16尾鲇类标本鉴定描记了鲇属鱼类1新种,即都安鲇Silurus duanensis sp.nov..新种具有下颌突出于上颌,背鳍条i-3,臀鳍条数较少;颌须长;犁骨齿带分成两片;胸鳍硬刺前缘有颗粒状突起,后缘有明显的锯齿;后鼻孔呈短管状,且呈圆形张开等综合特征.上述性状可区别于属内其他已知种类.     

Monophyly of the catfish family Siluridae (Teleostei: Siluriformes), with a critique of previous hypotheses of the family's relationships

Monophyly of the Eurasian catfish family Siluridae is established according to five synapomorphies unique to the family: (1) palatine reduced to a small nodule; (2) lateral ethmoid and sphenotic contact by narrow extensions lateral to the frontal; (3) ossified transscapular ligament anteroposteriorly compressed; (4) distal radials of dorsal-fin pterygiophores absent; (5) articulations of anal-fin rays with pterygiophores posterodorsally shifted. Previous hypotheses of silurid non-monophyly or a close relationship of the Siluridae to the Malapteruridae, Plotosidae or Amblycipitidae are shown to be poorly supported by available evidence. Silurids share with other subgroups of the Siluroidea character states that are derived within the Siluroidea; these are described in an appendix. Additional character state evidence is needed before a hypothesis of sister-group relationshipi between the Siluridae and another siluroid subgroup can be proposed.     

Pterocryptis buccata, a new species of catfish from western Thailand (Teleostei: Siluridae) with epigean and hypogean populations

Pterocryptis buccata sp. nov. is described from the vicinity of Sai Yok, Kanchanaburi Province, western Thailand. It can be distinguished from all other congeners by its prominent mandibular muscles causing the cheeks to appear inflated and the following unique combination of characters: 54–61 anal-fin rays, 7 pelvic-fin rays, 50–52 vertebrae, 4 mandibular barbels and vomerine teeth present in 2 separate patches. An achromatic population inhabits the Sai Yok Noi cave. This is the first report of a cavedwelling catfish from Southeast Asia.