A revision of the akysid catfish genus Acrochordonichthys Bleeker

Pseudolaguvia moinensis, a new benthic miniature Asian catfish (Teleostei: Sisoridae) from Arunachal Pradesh, north-eastern India

“…Measurements were made point to point with digital calipers and data recorded to the nearest 0.1 mm. All measurements and counts were made on the left side of specimens whenever possible, following Ng & Kottelat (2013). Subunits of the head are presented as a percentage of head length (HL), and head length and measurements of body parts as a percentage of standard length (SL).…”

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

“…The shapes of the genital papillae have not been previously used as diagnostic characters in silurids, although they have been used successfully in other siluriform groups such as akysids (Ng & Ng, 2001), auchenipterids (Soares-Porto, 1998), clariids (Ng, 1999b) and sisorids (Ng & Kottelat, 1999). Given the importance of the reproductive structures in maintaining the historical individuality of lineages in the light of their role in breeding, it is surprising that they have not been used more frequently in diagnosing species.…”

“…the akysid catfish Acrochordonichthys, Ng & Ng, 2001), the only solution to which would be to examine large series of specimens. This was not possible so except for the case of P. cochinchinensis, where the observed variation in head width, head depth and pelvic-fin length (Figs 4,5 & 10) still enabled the use of these characters with some confidence as a diagnostic.…”

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

“…Another two diagnostic characters that have been found to be useful in distinguishing the Vietnamese species of Pterocryptis are the shapes of the genital papillae and the degree of fusion of the anal and caudal fins. The shapes of the genital papillae have not been previously used as diagnostic characters in silurids, although they have been used successfully in other siluriform groups such as akysids (Ng & Ng, 2001), auchenipterids (Soares-Porto, 1998), clariids (Ng, 1999b) and sisorids (Ng & Kottelat, 1999). Given the importance of the reproductive structures in maintaining the historical individuality of lineages in the light of their role in breeding, it is surprising that they have not been used more frequently in diagnosing species.…”

“…The difficulty of using morphometric measurements in diagnosing species of Pterocryptis is a problem that is also encountered among certain siluriform groups (e.g. the akysid catfish Acrochordonichthys, Ng & Ng, 2001), the only solution to which would be to examine large series of specimens. This was not possible so except for the case of P. cochinchinensis, where the observed variation in head width, head depth and pelvic-fin length (Figs 4,5 & 10) still enabled the use of these characters with some confidence as a diagnostic.…”