Garra hughi SILAS, 1955

Cardamom Garra

Etymology

Garra: vernacular Gangetic name for a particular species of “sand-digger,” which Francis Buchanan-Hamilton applied as a generic name for bottom-dwelling cyprinids “with no affinity to another genus”.

hughi: named in honour of the author’s brother,  Hugh M. Silas, who collected the type series.

Classification

Order: Cypriniformes Family: Cyprinidae

Distribution

Restricted to the Anamalai, Cardamom, Palani and Ashambu Hills of the Western Ghats mountain range, southern India, where it is known from the Pambar, Periyar, Neyyar, Kallada, and Vamanapuram river systems, plus tributary drainages within the Indira Gandhi Wildlife Sanctuary.

Type locality is ‘Stream in Lower Vauguvarrai Estate, High Range, Travancore, Kerala State, India’.

Habitat

Inhabits swiftly-flowing sections of headwaters and tributaries. The most favourable habitats contain clear, oxygen-saturated water which, allied with the sun, facilitates the development of a rich biofilm carpeting submerged surfaces.

Maximum Standard Length

120 -155 mm.

NotesTop ↑

G. hughi is occasionally available in the ornamental trade and may be labelled ‘chocolate algae eater’.

The original diagnosis of this species by Silas states that it can be identified by the following combination of characters: elongate body form; broad head; broadly rounded snout with no tubercles; absence of a proboscis and lateral lobes on the snout; total absence of scales on the ventral surface as far back as, and including, the area between the pelvic fins; absence of scales on the dorsal surface between the occiput and the origin of the dorsal fin; presence of two pairs of barbels; pharyngeals relatively long with two rows of teeth, the outer of which is enlarged; colour pattern comprising grey pigmentation on flanks and dorsal portion of body, yellowish-white on the ventral portion and abdomen, with a conspicuous dark lateral band extending from the upper angle of the opercle to the base of the caudal-fin along, and usually a dark blotch on the lateral line two scales from the base of the caudal peduncle.

The genus Garra is a particularly enigmatic grouping with new taxa described on a regular basis, while many of the existing ones may represent cases of misidentification or synonyms of other species. Some of the revisions have also been called into question, which has added further confusion. A full generic review would be ideal but is unlikely to materialise given the extensive distribution of its members which range from southern China across much of southeast Asia, India and the Middle East as far as north/central Africa.

Instead a number of less-extensive works published in recent years have resulted in a gradual, but continuing, improvement in knowledge, and it remains possible that the genus will be broken up into smaller taxa since the current assemblage is almost certainly polyphyletic.

Garra species are usually included in the subfamily Labeoninae/Cyprininae or tribe Labeonini (name varies with author) which by recent thinking is further divided into four subtribes; Labeoina, Garraina, Osteochilina, and Semilabeoina (Yang et al., 2012). The putatively monophyletic Garraina comprises a number of genetic lineages including Garra sensu stricto (which also includes Horalabiosa, Phreatichthys and possibly other genera), a small clade comprising Garra cambodgiensis and G. fascicauda (thus rendering Garra polyphyletic), Paracrossocheilus, and Gonorhynchus (which includes Akrokolioplax).

Two Garra species, G. imberba and G. micropulvinus, are placed in the Semilabeoina assemblage, and the generic name Ageneiogarra Garman, 1912 has been suggested for them, although this does not appear to have been widely followed (e.g. Kottelat, 2013). In addition, some genera which were previously considered to be close relatives of Garra species such as Discogobio, Discocheilus and Placocheilus, are now also placed in this subtribe.

All genera currently included in Garraina possess a lower lip modified to form a mental adhesive disc, allowing the fish to cling to surfaces in turbulent conditions. In most species the upper lip is almost entirely reduced and both the upper and lower jaw margins are keratinised, i.e., horny, and used to scrape food items from the substrate.

Garra species are distinguished from other Garraina members by the first two pectoral-fin rays usually being thickened, fleshy and unbranched, possession of 10-11 dorsal-fin rays, and a combination of internal characters. Some species have evolved particular environmental specialisms such as highly reduced eyes in hypogean forms or the ability to survive in thermal springs.

References

1. Silas, E. G., 1955 - Records of the Indian Museum (Calcutta) v. 52: 1-14
   Garra hughi, a new cyprinoid fish from the Western Ghats, Peninsular India, with notes on its bionomics.
2. Abraham, R. K., N. Kelkar and A. Biju Kumar, 2011 - Journal of Threatened Taxa 3(3): 1585-1593
   Freshwater fish fauna of the Ashambu Hills landscape, southern Western Ghats, India, with notes on some range extensions.
3. Arunachalam, M., M. Raja, S. Nandagopal and R. L. Mayden, 2013 - International Journal of Zoology Research 3(1): 62-68
   Garra palaruvica, a new cyprinid fish (Cypriniformes: Cyprinidae) from Kerala, Western Gnats, Peninsular India.
4. Arunachalam, M., S. Nandagopal and R. L. Mayden, 2014 - Species 10(24): 58-78
   Two new species of Garra from Mizoram, India (Cypriniformes: Cyprinidae) and a general comparative analyses of Indian Garra.
5. E. Zhang, 2005 - Zoological Studies 44(1): 130-143
   Phylogenetic relationships of labeonine cyprinids of the disc-bearing group (Pisces: Teleostei).
6. Raju Thomas, K., M. J. George and C. R. Biju, 2002 - Journal of the Bombay Natural History Society 99(1): 47-53
   Freshwater fishes of southern Kerala with notes on the distribution of endemic and endangered species.
7. Stiassny, M. L. J. and A. Getahun, 2007 - Zoological Journal of the Linnean Society 150(1): 41-83
   An overview of labeonin relationships and the phylogenetic placement of the Afro-Asian genus Garra Hamilton, 1922 (Teleostei: Cyprinidae), with the description of five new species of Garra from Ethiopia, and a key to all African species.
8. Yang, L., M. Arunachalam, T. Sado, B. A. Levin, A. S. Golubtsov, J. Freyhof, J. P. Friel, W-J. Chen, M. V. Hirt, R. Manickam, M. K. Agnew, A. M. Simons, K. Saitoh, M. Miya, R. L. Mayden, and S. He, 2012 - Molecular Phylogenetics and Evolution 65(2): 362-379
   Molecular phylogeny of the cyprinid tribe Labeonini (Teleostei: Cypriniformes).