Family AKYSIDAE Gill 1861 (Stream Catfishes)

Revised 31 July 2024
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Stream Catfishes
Subfamily AKYSINAE Gill 1861

Akysis Bleeker 1858 a– (Gr. ἀ), negative prefix, e.g., without; kýstis (Gr. κύστις), bladder, referring to absence of a swim bladder

Akysis bilustris Ng 2011 Latin for “that lasts two lustra,” i.e., 10 years, referring to fact that specimens in type series were collected in two expeditions exactly 10 years apart

Akysis brachybarbatus Chen 1981 brachýs (Gr. βραχύς), short; barbatus (L.), bearded, referring to shorter nasal barbels compared with the similar A. maculipinnis

Akysis clavulus Ng & Freyhof 2003 diminutive of clavus (L.), a nail, referring to conical tubercles on head and body

Akysis clinatus Ng & Rainboth 2005 Latin for bent or sunk (authors say slanting), referring to its steeply sloping dorsal profile

Akysis ephippifer Ng & Kottelat 1998 ephippium (L.), saddle; –ifer, from fero (L.), to have or bear, referring to saddle-shaped markings on body

Akysis fontaneus Ng 2009 Latin for of or from a spring, referring to type locality, a spring-fed stream

Akysis fuliginatus Ng & Rainboth 2005 Latin for sooty, referring to its dark coloration

Akysis galeatus Page, Rachmatika & Robins 2007 Latin for helmeted, referring to bony ridges on head

Akysis hendricksoni Alfred 1966 in honor marine biologist John R. Hendrickson (1921–2002), Vice-Chancellor of the East-West Center, University of Hawaii, who was Alfred’s first teacher in ichthyology; he also helped collect holotype

Akysis heterurus Ng 1996 héteros (Gr. ἕτερος), different; urus, from ourá (Gr. οὐρά), tail, referring to its truncate (vs. forked) caudal fin, “distinctly different” from its congeners

Akysis longifilis Ng 2006 longus (L.), long; filis (scientific Neo-Latin), thread-like or filiform thread, referring to its long barbels

Akysis maculipinnis Fowler 1934 macula (L.), spot; pinnis, Neo-Latin adjective of pinna (L.), fin, i.e., finned, referring to speckled fins

Akysis manipurensis (Arunkumar 2000)ensis, Latin suffix denoting place: Manipur, India, the only known member of the genus known from Manipur

Akysis microps Ng & Tan 1999 micro-, from mikrós (Gr. μικρός), small; ṓps (Gr. ὦψ), eye, referring to relatively small eye, smaller than that of the similar A. heterurus

Akysis patrator Ng, Pawangkhanant & Suwannapoom 2022 Latin for achiever or accomplisher, referring to how the discovery of this species closed a “significant gap” in the geographic distribution of the genus

Akysis pictus Günther 1883 Latin for painted or colored, referring to black coloration on anterior portion of body, which contracts into an irregular black band that runs along middle of posterior portion of body (which can be said to have a “painted on” effect or quality)

Akysis portellus Ng 2009 diminutive of porta (L.), gate or door, referring to its relatively small mouth

Akysis prashadi Hora 1936 in honor of Indian zoologist Baini Prashad (1894–1969), Assistant Superintendent (later Director), Zoological Survey of India, who studied this species in 1929

Akysis pulvinatus Ng 2007 Latin for elevated, referring to long base of adipose fin

Akysis recavus Ng & Kottelat 1998 Latin for curved inwards, referring to concave lateral margins of head

Akysis scorteus Page, Hadiaty & López 2007 Latin for leathern, referring to its leathery skin

Akysis variegatus (Bleeker 1846) Latin for “of different sorts,” particularly colors, described as having an orange body with four broad, transverse, irregular dark bands, the first band (surrounding head) marbled or reticulated with orange, and orange fins and barbels, “variegated with dark” (translation)

Akysis varius Ng & Kottelat 1998 Latin for variable, referring to highly variable number of serrae on posterior edge of pectoral spine

Akysis vespa Ng & Kottelat 2004 Latin for wasp, referring to its yellow-orange and brown striped pattern and to the painful sting its spines may inflict

Akysis vespertinus Ng 2008 Latin for of the evening (i.e., sunset and, hence, western), referring to its distribution in western Myanmar and being one of the westernmost species in the genus

Pseudobagarius Ferraris 2007 tautonymous with Akysis pseudobagarius Roberts 1989, proposed for members of the “pseudobagarius group” of Akysis

Pseudobagarius alfredi (Ng & Kottelat 1998) in honor of ichthyologist Eric R. Alfred (1931–2019), former director of the National Museum of Singapore, for his “pioneering” work on the freshwater fishes of Peninsular Malaysia

Pseudobagarius baramensis (Fowler 1905) ensis, Latin suffix denoting place: Baram River basin, Borneo, where it is endemic

Pseudobagarius eustictus Ng & Kottelat 2021 eústiktos (Gr. ἐὔστικτος), variegated, referring to its mottled head (in contrast with nearly uniform-colored heads of congeners from the Mekong River drainage)

Pseudobagarius filifer (Ng & Rainboth 2005) filum (L.), thread or filament; –fer, from fero (L.), to have or bear, referring to filamentous extensions of first pectoral-fin ray

Pseudobagarius fuscus (Ng & Kottelat 1996) Latin for dusky, referring to its mainly dusky brown dorsum

Pseudobagarius hardmani (Ng & Sabaj Pérez 2005) in honor of British ichthyologist Michael Hardman (b. 1978), then at the Natural History Museum (London), for his “pioneering” work on the molecular systematics of catfishes

Pseudobagarius inermis (Ng & Kottelat 2000) Latin for unarmed, referring to lack of serrations on pectoral spine

Pseudobagarius leucorhynchus (Fowler 1934) white-snouted, from leukós, (Gr. λευκός), white, and rhýnchos (Gr. ῥύγχος), snout, referring to white end of muzzle

Pseudobagarius macronema (Bleeker 1860) macro-, from makrós (Gr. μακρός), long or large; nḗma (Gr. νῆμα), thread or yarn, referring to longer maxillary barbels compared with Akysis variegatus, its presumed congener at the time [sometimes misspelled as macronemus]

Pseudobagarius meridionalis (Ng & Siebert 2004) Latin for southern, referring to distribution in Barito River drainage of southern Borneo

Pseudobagarius nitidus (Ng & Rainboth 2005) Latin for elegant, referring to its distinctive color pattern (chocolate-brown head and sides and yellow belly, with saddle-shaped yellow spots)

Pseudobagarius pseudobagarius (Roberts 1989) pseudo-, from pseúdēs (Gr. ψεύδης), false, referring to “striking superficial (but phylogenetically false) resemblance” to the sisorid genus Bagarius

Pseudobagarius similis (Ng & Kottelat 1998) Latin for like or similar, referring to its close resemblance to P. pseudobagarius

Pseudobagarius sinensis (He 1981) ensis, Latin suffix denoting place: Sinica (China); described in the genus Akysis, then believed to be the first of two species (the other being A. brachybarbatus) known from that country

Pseudobagarius subtilis (Ng & Kottelat 1998) Latin for very fine or delicate, referring to its relatively long and slender body


Warty Catfishes
Subfamily PARAKYSINAE Roberts 1989

Acrochordonichthys Bleeker 1857 akrochordón (Gr. ἀκροχορδών), wart or skin tag, referring to tuberculate skin of A. rugosus; ichthýs (Gr. ἰχθύς), fish

Acrochordonichthys chamaeleon (Vaillant 1902) referring to rugose skin with tubercles arranged in longitudinal rows along sides of body, similar to that of members of the lizard family Chamaeleonidae

Acrochordonichthys falcifer Ng & Ng 2001 falcis, genitive of falx (L.), sickle or scythe; –fer, from fero (L.), to have or bear, referring to smooth, recurved pectoral spine

Acrochordonichthys guttatus Ng & Ng 2001 Latin for speckled, referring to small brown spots on dorsal surface of head and body

Acrochordonichthys gyrinus Vidthayanon & Ng 2003 from gýros, (Gr. κύρτος), rounded or curved, referring to concave posterior margin of pectoral fin

Acrochordonichthys ischnosoma Bleeker 1858 ischnós (Gr. ισχνός), thin or lean; sṓma (Gr. σῶμα), body, presumably referring to its elongate body

Acrochordonichthys mahakamensis Ng & Ng 2001ensis, suffix denoting place: Mahakam River, eastern Borneo, type locality

Acrochordonichthys pachyderma Vaillant 1902 pachýs (Gr. παχύς), thick; dérma (Gr. δέρμα), skin, referring to rough on covering head and body

Acrochordonichthys rugosus (Bleeker 1846) Latin for wrinkled or shrivelled, referring to “glandular-verrucose” skin (translation), with warts (tubercles) on head, snout, cheeks, back, flanks and belly

Acrochordonichthys septentrionalis Ng & Ng 2001 Latin for northern, being the most northern member of the A. ischnosoma species group

Acrochordonichthys strigosus Ng & Ng 2001 Latin for lean, lank, thin or meager, referring to relatively slender body compared with other members of the A. ischnosoma species group

Breitensteinia Steindachner 1881ia, belonging to: Heinrich Breitenstein (1848–1930), German physician who served with the Dutch East Indies army; he collected fishes and reptiles in Borneo for Steindachner, including presumably type of B. insignis

Breitensteinia cessator Ng & Siebert 1998 Latin for an idle fellow, referring to its sluggish nature (congeners are described as being lethargic in aquaria)

Breitensteinia hypselurus Ng & Siebert 1998 hypsēlós (Gr. ὑψηλός), high; urus, from ourá (Gr. οὐρά), tail, referring to relatively tall neural spines of caudal vertebrae

Breitensteinia insignis Steindachner 1881 Latin for distinguished by marks, probably referring to “intense” brownish-purple spots on sides, and/or yellowish-white dorsal, pectoral and anal fins that are “more or less mottled with dark purple” (translations)

Parakysis Herre 1940 pará (Gr. παρά), near, i.e., similar to Akysis but lacking an adipose fin

Parakysis anomalopteryx Roberts 1989 anomalum (L.), anomalous (i.e., deviating from the general rule); ptéryx (πτέρυξ), fin, referring to different fin-ray counts compared with P. verrucosus, its only known congener at the time

Parakysis grandis Ng & Lim 1995 Latin for large, at up to 62 mm SL, largest member of genus known to date

Parakysis hystriculus Ng 2009 Latin for hairy or bearded, referring to its long accessory mandibular barbels

Parakysis longirostris Ng & Lim 1995 longus (L.), long; rostris, Neo-Latin scientific adjective of rostrum (L.), snout, referring to its relatively long snout

Parakysis notialis Ng & Kottelat 2003 Latin for southern, referring to its distribution in the Barito River drainage of southern Borneo

Parakysis verrucosus Herre 1940 Latin for warty, the skin “covered everywhere with very small granules or tubercles” [originally spelled verrucosa because Herre believed the genus was feminine]