Fishes of the genus Botia in the Indian Region - part 2

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Botia Gray, 1831 – type species Botia almorhae Gray, 1831

Synonyms:

Hymenphysa MClelland, 1839 (and its unjustified emendation Hymenophysa Bleeker, 1858 (see Part 2).

Diacantha Swainson, 1839

See Kottelat (2004: 12) for the characteristics of the genus.

Menon (1993) erected two complexes for the Botia species: the B. almorhae complex, and the B. striata complex (his B. berdmorei complex is not relevant here as that species belongs in Syncrossus Blyth, 1860 – see Grant (2001), and Kottelat (2004)). He did not define the complexes, but based on his comments on pages 12, 13 and 24, he appears to have grouped them together based on a combination of pattern and distribution. He considered that B. almorhae, B. birdi, B. histrionica and B. dario belonged to the B. almorhae complex, and B. striata to its namesake complex. I too consider that species complexes do exist within Botia, but differ slightly on their members. Without further study and specimens the description of the complex is only loosely based, and is like Menon, mainly based on body and head shape, size, and colour/pattern. Future DNA studies will be able to define them specifically and may of course produce different results. I know that this is not scientific but to the trained eye it is easy to see which species are closer to one than to perhaps others.

Botia almorhae complex

Members: B. almorhae; B. birdi; B. lohachata; sp. Teesta; sp. Kosi; (possibly B. blythi).

Diagnosis: Pattern consisting of black, grey, or brown Y and i bars (usually 3 Y’s and approximately 4-5 i’s) in young, which usually disintegrate and/or anastomose to varying degrees in ontogeny. Base colour whitish, yellow, golden, or very light green. Size up to approx. 16cm SL.

Botia dario complex

Members: B. dario; B. striata.

Diagnosis: Pattern consisting of usually 7-9 blue, green, grey or black body bars that usually contain thinner lighter bars within them, the bars can anastomose. Base colour usually yellowish to golden. Size up to approx. 12cm SL.

I have chosen B. dario as the namebearer of the complex (rather than B. striata as in Menon) as I have a hunch that B. dario will probably be the basal member of the complex.

Botia rostrata complex

Members: B. rostrata; sp. ‘Upper Brahmaputra’; sp. Ladder; (possibly B. blythi).

Diagnosis: Pattern consisting of 8-10 black to dark brown body bars that exhibit paler and numerous spots in juveniles, and in adults the bars can anastomose, sometimes completely obscuring the vertical bars on the anterior of the fish. Base colour whitish, or yellowish to gold, sometimes with greenish or bluish tinges. Size up to approx. 12cm SL.

Botia histrionica complex

Members: B. histrionica (all forms); B. kubotai; B. udomritthiruji.

Diagnosis: Pattern consisting of 5 black bars (1st across nape and opercle) in juveniles that have either no pale disintegration or (usually) 2-3 pale spots in small specimens. In adults some of the 5 bars can split into two, or can anastomose, disintegrate, and/or fragment to varying degrees. Base colour golden, yellow, light brown or whitish (sometimes with a hint of green). Size up to approx. 13 cm SL.

Botia dario (Hamilton, 1822)

Junior synonyms:

Cobitis geto Hamilton, 1822

Canthophrys (Diacantha) zebra Swainson, 1839

Botia macrolineata Teugels, De Vos & Snoeks, 1986

Preserved specimens used: BMNH 1855.12.26.691, Ganges River, India, presented by McClelland, 1 spec., c. 77mm SL; BMNH 1867.2.14.74-75, Cachar, India, presented by Colonel Playfair, 2 spec. c. 61mm SL – 67mm SL; BMNH 1870.11.30.47, North East Bengal, presented by T. Jerdon, 9 spec., c. 45 mm SL – 81 mm SL; MNHN 1984-0344, (paratypes of Botia macrolineata), “+/- 100 km from Bombay, India”, presented by M. Vanderweyer, 2 spec., 40.1 – 42.9 mm SL; CAS 94008, Ganges River, Patna, Bihar State, India, presented by Tyson Roberts, 3 spec. 60.9 mm SL – 63.1 mm SL; ANSP 85779, “Bombay”, presented by Bombay Natural History Society, 1 spec., 67.0 mm SL; AMS B.7534, “Sone River, Bengal”, presented by F. Day, 1 spec., 57mm SL.

Distribution: The type locality described by Hamilton was “northern rivers of Bengal”. This is not specific, but historic Bengal relates to the region which is now current day West Bengal and small parts of current day Bihar, Orissa, and Tripura (all states of India), and Bangladesh. Hora (1935) states that Hamilton’s original notes and what he knew of his journeys show that the specimen was from “Dumdumma”, which I believe may equate to Dum Dum in West Bengal, which is near Kolkata, and if correct would mean that the specimen probably came from the Hooghly River. It is definitely found in the states of Assam (Sen, 1985; Banarescu & Nalbant, 1968; Menon, 1993; and specimens above), Uttar Pradesh (Hora, 1922; Srivastava, 2004), Bihar (Srivastava, 2004; and specimens listed above), Arunachal Pradesh (Nath & Dey, 2000), and West Bengal (Shaw & Shebbeare, 1937, - Singhimari stream, and Chel River, Western Duars – Northern Bengal; Menon, 1993). Petr (1999) lists it as occurring in Gaylegphug River, southern Bhutan. Sen (1995) reports on specimens caught in Meghalaya (Khasi Hills, Jaintia Hills, and Garo Hills, which are connected to either the Brahmaputra River, or the Barak River, which connects to the Meghna River). Barak basin, Manipur (Vishwanath, 2002). Ataur Rahman (2005) reports it as being abundant in streams of Mymensingh, Sylhet, Dinajpur, Rangpur and Chittagong Hill-Tracts, all in Bangladesh. See under ‘Specimens’ for instances in the Ganges. It is therefore predominantly found in the middle to lower Brahmaputra River System (notably including the Meghna River and Barak River), and Ganges River System. Sen (1985 & 1995) lists it as occurring in Punjab but this is doubtful. It is not found in the waters of the Bombay [Mumbai] area (see under discussion of Botia macrolineata).

Meristics: Dii-iii 8-12; Pi 11-15; Vi 6-7; Ai-iii 5-6; C 19.

Colour and pattern: Base colour yellow (dusky or light), yellowish gold, or greenish gold. Snout dusky. A wide, dark bar across the top of the head, extends through and below the eye; sometimes the bar is not separate from the dusky area on the snout and therefore most of the head is dark. After the eye bar there is a bar that usually starts just above the lateral line, and the ventral half of the fish, covering edge of the operculum and the area on the body posterior to the insertion of the pectoral fin. The body then almost always has seven bars, which connect over the ridge of the back. The first bar starts around the nape area and almost always is angled diagonally backwards as it travels towards the ventral part of the body. The next bar along has a similar angle. The next bar anterior edge is almost always placed prior to the insertion of the dorsal fin spine. This bar also usually extends at a backward angle as it travels down towards the vent. The next bars anterior edge starts around the fourth or fifth branched dorsal ray insertion, its posterior edge starting around the insertion of the last dorsal fin rays; it is more vertical than the preceding bars. The next bar is also more vertical than the angled ones; its posterior edge is near the insertion of the anal fin. The next bar is almost vertical and its edges usually lie within the confines of the base of anal fin. The final bar is across the caudal peduncle, and sometimes extends onto the base of the caudal fin rays. Sometimes the bars have a thin line of the base colour within them (usually increasing in ontogeny). Sometimes the bars end in the ventral half, or join the next bar ventrally and/or dorsally, which can give the appearance of ‘u’, ‘n’, ‘v’, ‘Y’, ‘H’ or ‘o’ shapes (see Sane & Chhapgar, 1985, for 24 diagrams of the variations they found in specimens from Silchar, Assam (probably from Barak River?)). The bars can be slate grey, dark green, or almost black (darker the smaller the specimen). Across the base of the dorsal fin, the colouration of the two body bars usually extends on to the base of the rays and spine. Across the middle to slightly upper half of the dorsal fin, the spine and rays usually have a dark stripe. The first few rays of the pectoral fin are sometimes dusky; sometimes basal portions of the rays are dark, and sometimes there is a dark band on the rays along the middle of the fin. The ventral fins sometimes have a dark blotch at the base of some of the rays, which can sometimes cover the whole of the fin, apart from the distal portion. The anal fin sometimes has a diagonal band across the lower half. The caudal fin can have two (or three in specimens over 5cm SL) vertical bars, but they are sometimes angled diagonally. In some small (circa. under 3cm SL) specimens the first bar is in fact a blotch or spot, and the second bar is sometimes missing or very faint.

Discussion:

Cobitis geto, Hamilton, 1822 - Prior to Menon, 1993 (who classed C. geto as a junior synonym of B. dario) there had been much debate about the validity of C. geto. Günther (1868) appears to have been the first to consider C. geto as the young of B. dario and chose B. dario as the valid name, therefore establishing B. dario as the senior synonym. He did not give any justification for this. Day (1872) questionably listed it as a junior synonym of B. dario. Various other authors have listed it as valid, but without any or much explanation. In 1922 Hora classed C. geto as valid, based on some poorly preserved specimens from Gorakhpur (Uttar Pradesh, India). He said the “colouration is, however very distinct and seems to be characteristic of the species”. However, in 1932, Hora said that on further examination of the material he was of the opinion that C. geto is in reality a young form of B. dario; the slight differences in the colouration of the two forms being due to the age of the specimens.

I have considered whether C. geto is in fact Botia sp. ‘Upper Brahmaputra’. However, I do not consider that C. geto is synonymous with that species or with the similar B. rostrata (see under Botia sp. ‘Upper Brahmaputra’ for a discussion). Hamilton described C. geto and C. dario in the same publication. I have already discussed where Hamilton’s specimen of B. dario came from, and C. geto was described from the ponds in the north-eastern parts of Bengal. Hora (1935) states that the C. geto specimen was from Goalpara in Assam, which would mean the specimen probably was caught in the Brahmaputra. Rao (personal communication) has fished in the vicinity of Goalpara and did not catch any Botia, but as you can see under distribution, B. dario is found in the Brahmaputra. The specimens used are not preserved in any institution. When one looks at the drawings that he published of both species, a person unfamiliar with live Botia species may be excused for classing them as different. Hamilton obviously saw these fish (or the drawings of them) and considered them different because of the apparent differences one may see in the pattern, but also because of alleged morphological and meristic differences.

The drawing of B. dario is immediately recognisable as the fish we accept as B. dario today. The pattern is either of a semi-adult, but probably of an adult specimen as it has the paler lines distinctly formed within the dark bars, and the caudal fin has the 3 vertical/diagonal bars that have usually formed in specimens of 5cm SL+ (and Hamilton states that it grows to 2 or 3 inches in length). The drawing and text description of the colour and pattern shows that there was no pattern in any of the fins except the caudal. This can easily be explained by the fact that the fish was stressed (or dead!) at the time the notes and drawings were made, and that in some 5cm+ specimens the markings on those fins can be pale.

The colour and pattern of geto was described as “yellow colour, with transverse black bars running obliquely backward on the sides. One of the bars passes through the eye, which is black, with a gold-coloured ring round the pupil. The fins are yellow, with two black spots on the tail.” No size is given for the species, and the drawing is small. Although this does not definitely mean the specimen used was small, I consider that it was, based on how Hamilton’s drawings represented the fishes he described, and based on him stating it had no lateral line. If one looks at small B. dario specimens, some do exhibit a yellow base colour, darker bars than adults, and some have only two marks on the caudal fin (or with two more very pale indistinct marks at the extremities of the lobes). Sane & Chaapgar (1985) show one such small specimen, whose pattern is almost exactly like that of the drawing of C. geto. What is very noticeable is that in the drawing of C. geto, the dark area around the snout is shown, the band through the eye, and then seven bars on the body, the first few being more oblique than the others, and the gradually becoming vertical, and the last one being a wider band and covering the caudal peduncle. The pattern on the caudal, the colour, the number of body bars, and the placement of them represent a small B. dario.

In the text of the descriptions he also lists some other differences between the two species he described:

• He stated that B. dario had 6 pairs of barbels, whereas C. geto had 8. All Botia species have 8 barbels and Syncrossus 6, so we can rule out C. geto being a small Syncrossus (Yasuhikotakia have 6 also but it is doubtful that any occur in this area). We know that B. dario does have 8 barbels, so this must be a mistake in the text and the drawing.
• He stated that B. dario had a lateral line, and C. geto did not. As far as I can ascertain, all Botia species have a lateral line. If this is the case, I can only assume that this is a mistake by Hamilton, possibly caused by the small size of the specimen.
• He gave the following fin meristics: D11 P13 V8 A7 C18 in B. dario, D12 P13 V9 A7 C no count in C. geto. All these counts (some include branched and unbranched rays) are within the range for B. dario, with the exception of the ventral fin count. 9 ventral rays is not the norm for Botia, except one found in the Khasi Hills of Meghalaya (see further on); although sometimes the last branched ventral ray is split to the base and is sometimes counted as one ray, or two. Some Syncrossus species have 9 and the drawing of C. geto does seem to show a long pointed snout, but as stated earlier Hamilton clearly states that 8 barbels are present in C. geto, thus ruling out a young Syncrossus. I therefore consider that again, this count is a mistake, possibly due to the specimen being small.

Based on all the above information, I consider that C. geto was a young B. dario, and as Günther chose B. dario to have priority, C. geto is its junior synonym. However, this species has a wide distribution and there are meristic differences in fin ray count ranges. Having said this, the species appears to have a similar pattern and appearance across its range, but perhaps with some differences in the base colour and darkness of the body bars. DNA analysis may later show that certain populations are distinct from each other and the possibility of different subspecies being in existence shouldn’t be ruled out. If this happened, C. geto is an available name if the Assamese population turns out to be different to the population in the lower Ganges’ distributaries.

Botia macrolineata Teugels, De Vos & Snoeks, 1986 – This species was described from “+/- 100 km from Bombay, India”. It was based on 3 specimens. They were imported by a Belgian tropical fish company, and that is where the locality information will have originated. They had been kept alive in an aquarium for just over 2 years, before being preserved. This species first came to my attention, when Menon (1993) published a drawing as an addendum, and stated that it differed from B. dario by it having 11 branched dorsal rays, whereas B. dario was only known to have up to 10. The drawing used does look like a B. dario, but also seems to be slightly different. Upon obtaining the original description I was surprised that the drawing in Menon was not the drawing used in the description. The drawing used in the description is that of a B. dario. Having seen the paratypes of the species, these two represent a B. dario in all aspects.

The difference given by Teugels, De Vos & Snoeks is that B. dario has a smaller eye (2.1 – 2.3 times in snout length v 3.0 times in B. dario). In the specimens available to me I have found great variation in eye in snout length measurement. Even specimens of a similar size have different proportions. The range of 2.1-2.3 (based on 3 specimens) for B. macrolineata falls within the range I have found in 16 specimens (2.2 – 3.1).

The difference of 11 branched dorsal rays in B. macrolineata highlighted by Menon, is given as 11-12 by Teugels, De Vos & Snoeks. Two of lot BMNH 1870.11.30.47 have 11, and one has 12 branched rays (the last ray is not always branched). The AMS specimen has 11. Sen (1995) reports on some of his specimens having 11, and I have seen the images of live B. dario specimens which also have 11.

Teugels et al also give a caudal fin ray count of 26-28, but this count includes the procurrent and outermost principal rays.