Abstract:
We describe a new species of Horabagrus,
found in sympatry with H.
nigricollaris, from
the Chalakkudy river basin in Kerala, South India.
Horabagrus obscurus, new species, differs
from the two other known species in the genus in its
colour pattern, lesser body width at the pectoral
girdle, shorter barbels and total vertebral counts.
Differences in partial sequences of the mitochondrial
COI and CytB genes also serve to distinguish the new
species from congeners. The new discovery reasserts
the importance of the Chalakkudy river basin as a
hotspot of piscine diversity in the Western Ghats,
(Kumar, R.G et. al. 2024). Colouration:
Live specimens exhibit a greenish-brown body colour,
mottled with black, darker dorsally. Belly white,
sometimes with diffused yellow colour in the region
of transition. The head is dark, almost black, above
the lower margin of the orbit, white below. There
is a black humeral spot, roughly about the same diameter
as the eye, with a yellow to white patch immediately
antero-ventral to it. The caudal fin is reddish orange,
with its base, upper, lower and outer margins outlined
in black. The anal fin is reddish orange, margined
in black. The dorsal fin is dark brown to black, sometimes
with a diffuse white distal margin, (Kumar, R.G et.
al. 2024). Habitat: The species is
currently known from the Chalakkudy river basin between
the Athirapilly waterfalls and the dam at Thumburmuzhy.
The habitat in this region features rapid water flow
over a hard substrate of bedrock. Sympatric species
include H. nigricollaris, Osteochilichthys
longidorsalis, Sahyadria chalakkudiensis,
D. filamentosa, Garra surendranathanii
and Labeo nigrescens, (Kumar, R.G et. al.
2024). Aquarium Care: Will need
a large tank with places to hide as they are extremely
nocturnal and will only be seen sporadically during
the day. Diet: Will eat most prepared
foods and is an easy fish to keep as long as tankmates
are not too small as they will eat small fish. Etymology:
The specific name obscurus: From the Latin
obscurus, meaning dark or cloudy, a reference
to the colour pattern of the fish. The word obscure
in English also means cryptic or ambiguous and refers
to the confusion between H. obscurus
and the sympatric H. nigricollaris.
Common
Name:
None
Synonyms:
None
Family:
Horabagridae
Distribution:
Asia:Chalakkudy River basin, Western Ghats of
India.
Size:
25.0cm. (10ins)
Temp:
23-25°C (73-77°F)
p.H.
6.5-7.2.
Reference:
Fish
in the News2024
Kumar, R.G., Ravi, C., Krishnaprasoon, N.P. &
Basheer, V.S. 2024. A new sympatric species
of Horabagrus (Siluriformes: Horabagridae) from the
Chalakkudy river basin in Kerala, India. Indian Journal
of Fisheries, 71 (4): 20-26.
Horabagrus
obscurus Paratype-In life from the Chalakkudy River
at Vettilappara
Horabagrus
obscurus Paratype-In life from the Chalakkudy River
at Vettilappara
Horabagrus
obscurus Paratype-In life from the Chalakkudy River
at Vettilappara
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