Olyra praestigiosa

Ng, Heok Hee & Ferraris Jr, Carl J., 2016, A new species of anguilliform catfish (Actinopterygii: Siluriformes: Bagridae) from Bangladesh and northeastern India, Zootaxa 4079 (3), pp. 381-387: 382-384

publication ID

http://doi.org/10.11646/zootaxa.4079.3.6

publication LSID

lsid:zoobank.org:pub:724B3E5B-EA3C-4F97-A033-E796F05D381A

persistent identifier

http://treatment.plazi.org/id/D2BD8935-E036-4342-A136-C2EFA3DA6201

taxon LSID

lsid:zoobank.org:act:D2BD8935-E036-4342-A136-C2EFA3DA6201

treatment provided by

Plazi

scientific name

Olyra praestigiosa
status

new species

Olyra praestigiosa  , new species

( Fig. 1View FIGURE 1)

Olyra kempi  (non Chaudhuri)— Ataur Rahman, 2005: 191, Fig. 139; Vishwanath et al., 2007: 144. Olyra longicaudata  (non M’Clelland)— Biswas et al., 2007: 84; Patra, 2011: 1612, Image 3; Arunachalam et al., 2013a: 55, Figs. 5, 6; 2013b: 7.

Olyra horae  (non Prashad & Mukherji)— Pathak et al., 2013: 504, Fig. 1AView FIGURE 1.

Type material. Holotype: UMMZ 250262View Materials, 74.1View Materials mm SL; India: West Bengal, Darjeeling District, Kalimpong Subdivision, Chel River , approximately 1.25 km N of Gorubathan, 26°58’19.6”N 88°41’56.3”E; A. Rao (donated), 21 February 2014GoogleMaps  .

Paratypes: ZRCAbout ZRC 54729View Materials (1), 48.6 mm SL; data as for holotypeGoogleMaps  . UMMZ 243661View Materials (2): 56.3–66.8 mm SL; India: West Bengal, Tista River at Tista Barrage , 26°45’10”N 88°34’11”E; H. H. Ng et al., 15 April 2004GoogleMaps  . UMMZ 243660View Materials (1), 87.7 mm SL; India: West Bengal, Karotowa River at Ambari Barrage , 26°35’40”N 88°29’48”E; H. H. Ng et al., 14 April 2004GoogleMaps  . UMMZ 208790View Materials (3), 59.8–71.1 mm SL; Bangladesh: Sylhet, Piyain Gang River at Sangram Punji, 2.4 km downstream from Indian border, 25°11’N 89°59’E; W. J. Rainboth & A. K. Ataur Rahman, 21 February 1978GoogleMaps  . UMMZ 208635View Materials (9), 60.1–101.7 mm SL; Bangladesh: Sylhet, Piyain Gang River at Sangram Punji, 400 m downstream from Indian border, 25°11’N 92°1’E; W. J. Rainboth & A. K. Ataur Rahman, 19 February 1978GoogleMaps  . UMMZ 208811View Materials (5), 54.0– 117.9 mm SL; data as for UMMZ 208635; W. J. Rainboth & A. K. Ataur Rahman, 21 February 1978GoogleMaps  .

Diagnosis. Olyra praestigiosa  is distinguished 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 9–16% 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.

Description. Morphometric data in Table 1. General appearance as in Fig. 1View FIGURE 1. Body anguilliform, depressed anterior to dorsal fin, becoming more terete posteriorly and more compressed caudally. Dorsal profile from snout margin to base of dorsal-fin spine slightly convex, relatively straight from dorsal-fin base posteriorly to end of adipose-fin base, sloping dorsally from end of adipose-fin base to caudal-fin base. Ventral profile of head slightly convex, nearly straight from posterior margin of branchiostegal membranes to end of anal-fin base, and sloping ventrally along caudal peduncle. Lateral line complete, reaching compound caudal complex. Anus located at one third distance from base of posteriormost pelvic-fin ray to anal-fin origin. Urogenital papilla elongate (in males) and separate from anus, located one sixth of distance between center of anus and anal-fin origin. Vertebrae 21+25=46 (1); 21+26=47 (5); 22+25=47 (3); 23+24=47 (1); 22+26=48 (5); 23+25=48 (4) or 23+28=51* (1).

Head depressed, neurocranial roof covered with thick skin. Snout spatulate, rounded when viewed dorsally; with dorsolateral groove accommodating maxillary barbel immediately posterior to its insertion and extending posteriorly to anterior orbital margin. Upper and lower jaws almost equal, with upper jaw projecting very slightly beyond lower jaw. Lips thickened. Nostrils widely separated. Anterior nares tubular, immediately above margin of upper lip. Posterior nares closer to eye than to snout tip; anterior margin confluent with posterior base of nasal barbel. Branchiostegal membranes free, joined to isthmus only at gular apex and not overlapping medially, with six (2) branchiostegal rays. Gill rakers 1+10 (2). Eye small, subcutaneous, ovoid; closer to snout tip than to opercle margin; skin covering eye thin and translucent. Interorbital area markedly concave. Premaxillary teeth short, conical, arranged in crescentic band. Mandibular teeth small, conical, pointed, arranged in crescentic band interrupted at middle. Four pairs of barbels. Nasal barbel short, reaching midway between posterior margin of eye and base of pectoral-fin spine. Maxillary barbel long, reaching beyond base of last pectoral-fin ray. Outer mandibular barbel just reaching base of last pectoral-fin ray. Inner mandibular barbel short, about two-thirds length of outer mandibular barbel.

Dorsal-fin margin convex, with i,7 (22) rays; first and second dorsal-fin elements unossified. Base of first fin element almost at vertical through pelvic fin insertion. Base of dorsal fin, including basal parts of rays, covered by thick skin. Seven basal radials supporting dorsal fin, first basal radial associated with neural spine of vertebra 11 or 12 and last basal radial above vertebra 16 or 17. Pectoral fin with strong, sharp spine and 4,i (1), 5,i* (2), 6 (11), 6,i (4) or 7 (4) fin rays. Spine short, with 7–12 erect serrae along anterior margin and 8–15 retrorse serrae on posterior margin. Pelvic fin with i,5 (22) rays. Anal fin elongate, with vi,10,i (4), vi,11,i (1), vii,10,i (4), vii,11,i (4), viii,10,i (2), x,8,i (1), viii,11,i (3), ix,10,1 (1), x,10,i* (1) or vii,14,i (1) rays; ventral margin straight. Adipose fin low, with short base; originating at about level of ninth or tenth anal-fin ray. Adipose fin terminating as small oar-like projection, posterior margin separate from dorsal procurrent fin rays of caudal fin. Caudal fin strongly forked, with i,6,6,i (22) rays; upper lobe 1.5–1.7 times as long as lower.

Coloration in alcohol: dorsal and lateral surfaces of head and body brown, fading to cream on ventral surfaces. Three darker brown, moderately broad longitudinal stripes present on flanks, extending from immediately posterior to opercle to base of caudal fin, becoming very indistinct posterior to middle of anal-fin base: dorsal, medial and ventral stripes above, along and below lateral myoseptum, respectively. Longitudinal stripes, adipose fin, and fin rays and membranes of median fins darker brown. Paired fins dark brown dorsally, cream ventrally. Nasal and maxillary barbels brown dorsally, cream ventrally. Mandibular barbels cream. Live coloration similar, but considerably darker ( Fig. 2View FIGURE 2).

Etymology. The specific name comes from the Latin adjective meaning “full of deceitful tricks”, in allusion to the confusion surrounding the identity of this species (see Chresonymy and Discussion).

Habitat. Olyra praestigiosa  was collected from a small river with a substrate of sand, mud and rocks ( UMMZAbout UMMZ 243660). The current was moderate and the water was turbid. Other fish species collected at this habitat were: Barilius bendelisis (Hamilton 1807)  ( Cyprinidae  ), Danio dangila (Hamilton 1822)  ( Cyprinidae  ), Devario devario (Hamilton 1822) ( Cyprinidae  ), Pethia conchonius (Hamilton 1822)  ( Cyprinidae  ), Salmostoma phulo (Hamilton 1822)  ( Cyprinidae  ), Botia almorhae Gray 1831 ( Botiidae  ), Canthophrys gongota (Hamilton 1822)  ( Cobitidae  ), Lepidocephalichthys guntea (Hamilton 1822)  ( Cobitidae  ), Paracanthocobitis botia (Hamilton 1822)  ( Nemacheilidae  ), Psilorhynchus balitora (Hamilton 1822)  ( Psilorhynchidae  ), Mystus vittatus (Bloch 1794)  ( Bagridae  ), Parambassis baculis (Hamilton 1822)  ( Ambassidae  ), P. ranga (Hamilton 1822)  ( Ambassidae  ), Badis kanabos Kullander and Britz 2002  ( Badidae  ), Channa punctata (Bloch 1793)  ( Channidae  ), Glossogobius giuris (Hamilton 1822)  ( Gobiidae  ) and Macrognathus pancalus Hamilton 1822  ( Mastacembelidae  ).

Distribution. Known from the Brahmaputra River drainage in Bangladesh and northeastern India ( Fig. 3View FIGURE 3).

ZRC

Zoological Reference Collection, National University of Singapore

UMMZ

University of Michigan, Museum of Zoology

Kingdom

Animalia

Phylum

Chordata

Class

Actinopterygii

Order

Siluriformes

Family

Bagridae

Genus

Olyra

Loc

Olyra praestigiosa

Ng, Heok Hee & Ferraris Jr, Carl J. 2016

2016
Loc

Olyra horae

Pathak 2013: 504

2013
Loc

Olyra kempi

Arunachalam 2013: 55
Patra 2011: 1612
Vishwanath 2007: 144
Biswas 2007: 84
Ataur 2005: 191

2005