Trichogenes longipinnis

Trichogenes longipinnis
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Family: Trichomycteridae
Subfamily: Trichogeninae
Isbrücker, 1986
Genus: Trichogenes
Britski & Ortega, 1983
Species: T. longipinnis
Binomial name
Trichogenes longipinnis
Britski & Ortega, 1983

Trichogenes longipinnis is a species of catfish (order Siluriformes) of the family Trichomycteridae, and the only species of the subfamily Trichogeninae.[1]

Contents

Distribution

T. longipinnis is endemic to coastal streams in the Atlantic forest between Rio de Janeiro and São Paulo States in southeastern Brazil.[2][3]

Description

The spotted colour pattern differs consistently between stream populations, indicating genetic differentiation.[3] This fish grows to about 14 centimetres (5.5 in) SL in males and 10.6 cm (4.2 in) SL in females.[2]

Ecology

This catfish dwells in pools beneath small waterfalls in steep hill streams flowing over rocky and sandy substrates.[3] The density of these fish varies from 3 to 25 individuals per square metre. At densities of 18 to 25 individuals per square meter, these fish aggregate in loose groups of up to 30 individuals. However, the largest ones tend to be solitary and territorial.[2]

Unlike most trichomycterids which are bottom dwelling and nocturnal, T. longipinnis is nektonic and active both during daytime and at night, with juvenile and small adults being more active at daytime than large adults.[3]

This catfish uses visual, tactile, and chemo-sensory orientation to feed on bottom-dwelling aquatic and terrestrial insects in the water column or on the surface.[3] Diet includes immature aquatic insects, crustaceans, adult terrestrial winged insects whole or fragmented, as well as carrion. These fish forage mostly by scanning the bottom, the barbels touching the substrate, but visual oriented drift feeding is also employed by smaller individuals. While foraging, it may bury into sand or plant debris and sift through with its gill openings and mouth.[2]

This species reproduces at the onset of rainy season.[2]

T. longipinnis is restricted to steep hill stream stretches, and is absent in streams on gently sloping terrain dominated by Astyanax characids. The catfish possibly developed, or retained, its characid-like role (diurnal, nektonic, and insectivorous) in separately with this more widespread tetra.[3]

Conservation

Due to restricted distribution, specialized habitat, and differentiated populations, the vulnerable (VU B1+2bc) status in the IUCN List is proposed.[3] However, this species is not yet listed on the IUCN Red List.[2]

References

  1. ^ Ferraris, Carl J., Jr. (2007). "Checklist of catfishes, recent and fossil (Osteichthyes: Siluriformes), and catalogue of siluriform primary types" (PDF). Zootaxa 1418: 1–628. http://silurus.acnatsci.org/ACSI/library/biblios/2007_Ferraris_Catfish_Checklist.pdf. 
  2. ^ a b c d e f Froese, Rainer, and Daniel Pauly, eds. (2007). "Trichogenes longipinnis" in FishBase. July 2007 version.
  3. ^ a b c d e f g Sazima, Ivan (March 2004). "Natural history of Trichogenes longipinnis, a threatened trichomycterid catfish endemic to Atlantic forest streams in southeast Brazil". Ichthyol. Explor. Freshwaters 15 (1): 49–60.