Brahmaputra River Drainage Research Articles

Glyptothorax heokheei, a new species of catfish (Teleostei: Sisoridae) from the Brahmaputra River drainage, Arunachal Pradesh, Northeast India.

Glyptothorax heokheei, a new species of sisorid catfish is described from the Brahmaputra River drainage in India. It can be distinguished from all congeners, exceptG. dikrongensis,G. indicus,G. rugimentumandG. obliquimaculatus, in having the unculiferous striae of thoracic adhesive apparatus extending anteriorly onto gular region.Glyptothorax heokheeiis distinguished fromG. dikrongensisandG. obliquimaculatusin having a slender body at the anus, more serrations on posterior margin of pectoral-fin spine, greater number of branched anal fin rays, and the extremity of dorsoposterior margin of adipose fin uniformly convex (vs. sharply angular). It differs fromG. rugimentumin having a chevron-shaped (vs. rhomboidal) thoracic adhesive apparatus, more serrations on posterior margin of pectoral-fin spine, and lacking vertical bars on body.Glyptothorax heokheeidiffers fromG. indicusin having a shorter post-adipose distance, smaller interorbital width, more serrations on posterior margin of pectoral-fin spine and nasal barbel not reaching (vs. reaching) anterior margin of eye.Glyptothorax heokheeiis the fifth species ofthe genuspossessing unculiferous ridges of thoracic adhesive apparatus extending anteriorly onto the gular region.

Embryonic development of the threatened freshwater pipefish Microphis deocata (Hamilton, 1822)

The present study provides the first comprehensive embryonic development of the freshwater Syngnathid fish species, Microphis deocata (Hamilton), a Near Threatened pipefish endemic to the Brahmaputra River drainage in Northeast India and Bangladesh. Microphis deocata is a Gastrophori species as the males develop an abdominal brood pouch. Mature individuals were collected and maintained in well-aerated aquaria under controlled conditions to induce natural spawning. The number of eggs within the males' brood pouch ranged from 17 to 22 (for n = 10), measuring 0.7–1.0 mm in diameter. A total of 10 developmental stages could be recognized under four developmental periods namely, early embryogenesis, eye development, snout formation and juvenile. However, sensitivity, and therefore mortality, while handling of this species restricted the study from reporting the exact time intervals for stages following the blastodisc formation ~48 hr post fertilization. A newborn larvae measures ~14 mm and is free-swimming with distinct dorsal fin (with 31–32 rays) and a sector-shaped caudal fin (with 8–9 rays). The study aims to provide baseline information on the embryology of M. deocata in culture condition which will be helpful for future studies on conservation biology, population status and management of this species.

Length-weight relationships of four endemic snakeheads [Channa andrao Britz, 2013, Channa aurantimaculata Musikasinthorn, 2000, Channa bleheri Vierke, 1991, and Channa stewartii (Playfair, 1876)] from the Brahmaputra drainage, northeast India

The paper provides the Length–weight relationships (LWRs) for four endemic snakehead fish species namely Channa andrao Britz, 2013, Channa bleheri Vierke, 1991, Channa aurantimaculata Musikasinthorn, 2000 and Channa stewartii (Playfair, 1876), based on seasonal catches along the Brahmaputra river drainage from October 2016 to May 2018, using cast net (mesh size: 10–20 mm), scoop net (mesh size: 05–10 mm) and bamboo traps. Total lengths (TL) (nearest to 0.1 cm) and body weights (nearest to 0.1 g) were taken respectively. The b values in the LWRs were 3.26 for C. andrao, 2.74 for C. bleheri, 3.04 for C. aurantimaculata, and for 2.78 C. stewartii respectively. For C. aurantimaculata (=36.2 cm), C. bleheri (=14.4 cm) and C. stewartii (=29.7 cm) each, a new maximum total length (TL) was recorded.

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

A new species, Olyra parviocula, is described from the Kameng River, Brahmaputra River drainage in Arunachal Pradesh, northeastern India. The new species differs from congeners in having small eye diameter 5–8% HL; short adipose fin, not confluent with caudal-fin, its base length 9–12% SL; dorsal-fin branched rays 6; anal-fin rays viii–xi, 8–10 and maxillary barbel almost reaching pelvic-fin base. A key to identification of all valid species of Olyra is provided.

Badis pancharatnaensis, a new percoid fish species from Brahmaputra River drainage, Assam, India (Teleostei: Badidae)

Badis pancharatnaensis, a new percomorph, is described from the Brahmaputra River drainage of Assam, India. It is distinguished from its congeners by having the following combination of characters: a conspicuous black blotch on the superficial part of cleithrum; pointed soft dorsal, anal, and pelvic fins, the 2nd soft ray of pelvic-fin reaching slightly beyond the vent; 13 ‒ 14 pectoral-fin rays; circumpeduncular scales 14 ‒ 17; body depth 28.2 ‒ 33.8% of SL; interorbital distance 7.1 ‒ 9.4% of SL; and 28 number of vertebrae.

DNA barcoding of Amblyceps congeners (Siluriformes: Amblycipitidae) from Brahmaputra drainage in northeast India

The genus Amblyceps is recognized with 18 valid species inhabiting in fast flowing rivers mostly in South and Southeast Asia. We generated 10 mtCOI sequences for four species of Amblyceps from Brahmaputra River drainage that along with conspecific database sequences were analysed in MEGA and Mr. Bayes while Automatic Barcode Gap Discover (ABGD) was performed at web interface. Lowest between species K2P ranged from 8.7% to 16.4% compared to highest within species K2P of only 2.2%. Molecular data clearly delineated studied Amblyceps congeners into four distinct species by all the three methods of analysis employed that was congruent with the morphology based identification at species level, except a minor morphological variation observed for A. mangois specimens. Our results agree with the recent resurrection of A. arunchalensis from synonym of A. mangois. We provide three new sequences for A. laticeps and identified a mislabelled sequence of A. apangi in database.

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.

Creteuchiloglanis arunachalensis, a new species of glyptosternine catfish (Teleostei: Sisoridae) from Arunachal Pradesh, northeastern India

A new glyptosternine catfish, Creteuchiloglanis arunachalensis is described on the basis of a single specimen collected from the upper Brahmaputra River drainage, northeastern India. The new species is distinguished from its congeners by the following characters: shorter adipose-fin base (25.9 vs. 26.2–37.3 % standard length; SL) except C. longipectoralis; shorter maxillary barbel (71.2 vs. 75.2–99.8 % head length) except C. macropterus; and longer prepelvic (45.4 vs. 36.4–44.9 % SL) except C. brachypterus. It can be further differentiated by a combination of the following characters: pectoral fin not reaching pelvic-fin origin; pelvic fin not reaching at vertical through adipose-fin origin; pale patches on body except occipital region; absence of milky-white patch on the base of posterior end of maxillary barbel; longer post adipose distance (10.1 % SL); tip of rectal lobe obtusely rounded; caudal-fin lobes equal; posterior margin of caudal fin slightly convex; adipose-fin separate from caudal fin; and caudal fin with broad bean-shaped medial band.

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 6.6-7.4% HL interorbital distance 28.3-28.7% HL, head length 23.7-24.3% SL, wedge-shaped central depression in throracic adhesive apparatus devoid of skin ridges, unculiferous ridges of thoracic adhesive apparatus not extending anteriorly onto gular region, pectoral fin length 21.4-22.8% SL, dorsal-fin spine length 11.6-13.9% SL, dorsal-to-adipose distance 26.6-26.8% SL, body depth at anus 11.2-11.4% SL, pelvic fin length 16.5-18.3% SL, adipose-fin base length 13.1-14.3% SL, anal-fin base length 13.4-14.0% SL, caudal peduncle length 20.9% SL, caudal peduncle depth 7.7% SL (1.4-1.5 times in body depth at anus), absence of distinct pale midlateral stripe on body, and 36 total vertebrae. Glyptothorax striatus, the type species of the genus, is also rediagnosed and redescribed in this study.

Pseudolaguvia viriosa, a new catfish (Teleostei: Sisoridae) from north-eastern India

This study describes Pseudolaguvia viriosa, a new miniature sisorid catfish from the Brahmaputra River drainage in Ar-unachal Pradesh, northeastern India. Pseudolaguvia viriosa can be distinguished from congeners in having a combinationof: eye diameter 10–15% HL, interorbital distance 35–38% HL, head width 21.5–23.5% SL, thoracic adhesive apparatusreaching beyond base of last pectoral-fin ray, pectoral spine length 26.9–32.9% SL, dorsal spine length 23.4–29.0% SL,dorsal spine with anterior edge smooth or with rugose surface only on distal third of spine, body depth at anus 16.9–19.0%SL, length of adipose-fin base 12.5–15.4% SL, caudal peduncle length 14.8–17.7% SL, caudal peduncle depth 7.4–9.8% SL, caudal-fin length 26.5–32.4% SL, 28–29 vertebrae, and one or more distinct pale bands encircling body.

Amblyceps cerinum, a new catfish (Teleostei: Amblycipitidae) from northeastern India

Amblyceps cerinum, a new South Asian amblycipitid catfish species, is described from the Brahmaputra River drainage in northern West Bengal, India. The new species can be distinguished from congeners in having a combination of upper jaw longer than lower, incomplete lateral line terminating beneath posterior insertion of dorsal fin, length of adipose-fin base 32.4–38.3% SL, caudal peduncle length 21.9–24.5% SL, caudal peduncle depth 9.2–11.2% SL, 41–44 postWeberian vertebrae, posterior end of adipose fin separated from dorsal procurrent caudal-fin rays by distinct notch, and truncate caudal fin. The taxonomic status of A. tenuispinis is also discussed and a neotype designated for this species.

Redescription of Batasio merianiensis, a catfish (Teleostei: Bagridae) from northeastern India

The bagrid catfish Batasio merianiensis was described from only the holotype collected in the Brahmaputra River drainage, Assam, northeastern India. This poorly known catfish is rediagnosed and redescribed on the basis of fresh material in this study. Batasio merianiensis is diagnosed from congeners in having a combination of the following characters: length of adipose-fin base 16.9-22.2 % SL, dorsal fin when appressed not reaching anterior origin of adipose fin, body depth at anus 15.2-18.4% SL, caudal peduncle depth 9.7-11.5% SL, eye diameter 18.3-25.9% HL, vertical dark brown bars on head and body, and absence of dark mid-dorsal stripe.

Pseudolaguvia ferula, a new species of sisoroid catfish (Teleostei: Erethistidae) from India

Pseudolaguvia ferula, a new species of erethistid catish, is described from the Brahmaputra River drainage in India. It can be distinguished from congeners in having a terete (vs. depressed) head and body, manifested in the narrower head width (17.1–19.1% SL vs. 19.4–23.4), a smaller anterior fontanel (about one third the length of the frontals vs. at least half the length), and very faint, poorly contrasting cream bands that are sometimes absent on some individuals (vs. sharply contrasting cream bands on a brown body). It can be further distinguished from congeners in having a unique combination of the following characters: dorsal-spine length 17.3–18.7% SL, pectoral-spine length 20.2–24.3% SL, pelvic-fin length 13.0–14.7% SL, length of adipose-fin base 11.5–13.0% SL, caudal peduncle depth 6.9–7.8% SL, body depth at anus 12.1–13.8% SL, eye diameter 8.6–11.7% HL, vertebrae 28–30, and thoracic adhesive apparatus reaching to midway between bases of last pectoral-fin ray and first pelvic-fin ray. with its unculiferous ridges joined at their posterior ends.

The identity of Batasio tengana(Hamilton, 1822), with the description of two new species of Batasio from north‐eastern India (Teleostei: Bagridae)

Batasio tengana is redescribed on the basis of fresh material and a neotype designated. Two new species are described: Batasio fasciolatus n. sp. is described from material previously identified as B. tengana from the Brahmaputra River drainage and can be distinguished from congeners in having a combination of five to six vertical dark brown bars on a light brown body, dorsal‐spine length 13·6–16·8% standard length (LS), pectoral‐spine length 12·7–14·3%LS, and eye diameter 16·5–18·8% head length (LH). Batasio spilurus n. sp. is described from the Brahmaputra River drainage in Assam and can be distinguished from congeners in having a short adipose‐fin base (12·6–12·8 v. 14·5–33·3%LS) and more slender caudal peduncle (5·7–6·2 v. 6·7–11·8%LS).

Two new species of Pseudolaguvia (Teleostei: Erethistidae) from Bangladesh

Two new South Asian catfish species of the family Erethistidae, Pseudolaguvia inornata and Pseudolaguvia muricata, are described from the Brahmaputra and Feni River drainages in Bangladesh. Pseudolaguvia inornata from the Feni River drainage can be distinguished from congeners in having a uniform coloration with a pale mid-dorsal stripe and brown submarginal stripes on each lobe of the caudal fin, while P muricata from the Brahmaputra River drainage can be distinguished from congeners by its elongate dorsal and pectoral-fin spines.

Erethistoides sicula, a new catfish (Teleostei: Erethistidae) from India

A new species of erethistid catfish, Erethistoides sicula, is described from the Brahmaputra River drainage in northeast India. Erethistoides sicula differs from both E. montana and E. pipri in having a longer caudal peduncle (19.6–22.3% SL vs. 14.4–18.4) and shorter pectoral spine (14.6–28.0% SL vs. 30.7–32.1). It further differs from E. montana in having a dorsally projecting bony splint on the opercle immediately posterior to its articular facet with the hyomandibula (vs. splint absent) and from E. pipri in having a more slender head (13.4–15.1% SL vs. 16.4). The diagnostic characters of Erethistoides are discussed and four new synapomorphies are proposed to diagnose the genus.

A new catfish species of the genus Sisor Hamilton (Teleostei: Siluriformes) from Manipur, India

© Zoo Outreach Organisation; www.zoosprint.org Manuscript 1332; Received 15 February 2005; Finally accepted 01 July 2005; Date of publication 21 July 2005 1952 August 2005 | ISSN 0971-6378 ABSTRACT A new catfish of the genus Sisor Hamilton is described from the Barak River, a tributary of Brahmaputra River drainage in Manipur, India. Sisor barakensis sp. nov. differs from its closest congener S. chennuah Ng, in having larger eye (14.616.7% HL vs 9.9-11.4), narrower interorbital distance (16.019.8% HL vs 22.1-22.7), deeper body at anus (6.3-7.2% SL vs 5.6-5.8), longer dorsal spine (10.5-14.3% SL vs 7.9-9.5) and pectoral spine (18.6-20% vs. 16.9-18.2) length, deeper caudal peduncle (2.2-2.3% SL vs 1.4-1.6) and more number of serrations (15-21 vs 10) on posterior the edge of pectoral spine.

A revision of the south Asian sisorid catfish genus Sisor (Teleostei: Siluriformes)

The south Asian sisorid catfish genus Sisor is revised. Three new species are described in this study: S. chennuah from the Brahmaputra River drainage, and S. rheophilus and S. torosus from the Ganges River drainage. The body depth, snout length, eye size, shape of the nuchal plate and the numbers of pectoral spine serrations and lateral line ossicles are found to be diagnostic characters for the species. Sisor rabdophorus is redescribed and a neotype designated.

Phylogeny and biogeography of Morinaceae (Dipsacales) based on nuclear and chloroplast DNA sequences

Abstract The Morinaceae (Dipsacales) contains 13 species placed in Acanthocalyx, Cryptothladia or Morina, and is distributed from the mountains of southeastern Europe through the Himalayas to the Qinghai-Tibetan Plateau, mainly in alpine habitats. Sequence data from two chloroplast regions (the trnK intron and the trnL-F region) and the internal transcribed spacer (ITS) region of nuclear ribosomal DNA were used to infer phylogenetic relationships of Morinaceae and related Dipsacales. Both the nuclear and chloroplast datasets, as well as the combined data, provide strong support for relationships within the Valerina clade, placing Morinaceae as the sister group of a clade containing Valerianaceae and Dipsacaceae plus Triplostegia. The Morinaceae, Acanthocalyx, Cryptothladia, and a clade containing Morina and Cryptothladia, are all supported as monophyletic. However, Morina was found to be paraphyletic in several of our analyses, with Morina longifolia more closely related to Cryptothladia than to other Morina species. There is some evidence that Morina longifolia produces cleistogamous flowers, as do Cryptothladia species. Dispersal-vicariance analyses support the view that Valerina radiated initially within Asia, with subsequent movement into Europe in Morinaceae, Dipsacaceae, and Valerianaceae, and into the New World in Valerianaceae. For Morinaceae, as for a number of plant groups, the Brahmaputra river drainage marks a significant biogeographic divide, although this has been spanned within Acanthocalyx and the Morina- Cryptothladia lineage.