Metadata

Trichomycterus undescribed species

[Perez and Moodie 1993]

ORDERSUB-ORDERFAMILY
SiluriformesLoricarioideiTrichomycteridae

Note

Trichomycterus species from Guacharo Cave, Venezuela

The Guacharo Cave, Venezuela (10o10’33”N, 63o33’06”W) is famous both for the visit to it by Humboldt, and for its enormous population of oil birds, Steatornis caripensis. (For a schematic outline of the cave and details of these birds see Bellard Pietri (1957, 1960) and Brosset (1998)). In addition to the birds the cave also contains fishes and these have been studied by various workers over the years. Schultz (1949) identified these fishes as Pygidium conradi but said no more about them. Nalbant and Linares (1987) made a more detailed study, decided that both generic and specific placements were incorrect, and said that the fishes were Trichomycterus guianense. In the same year Romero (1987) published some experimental results on these animals under the name Trichomycterus conradi, suggesting that the animals breath air. Andreani (1987, 1990) made a thorough morphometric study of fishes from within and outside of the cave and concluded that neither of them were conradiPerez and Moodie (1993) suggested that the taxonomy requires re-evaluation and refers to the fishes simply as Trichomycterus sp.. They make the significant remark: “...we analysed genetic variation within a troglobite (obligatory cave-dweller) population of catfish belonging to the genus Trichomycterus that inhabits a subterranean stream in Guacharo Cave, and within an epigean population of the same genus living in a small stream outside the cave”. They clearly consider the cave fishes to be troglobitic. However their measurements of variation suggest that the epigean and hypogean populations are very closely related, and they suggest that either there has been a very recent separation of the populations or that there remains genetic continuity between them. Morphologically the cave population is only slightly different from the epigean one and shows no troglomorphic features. The latest study by Donascimiento and Villarreal (2005) used external morphology, osteology, myology and the cepahlic laterosensory system. This showed conclusively that the fishes are neither T. conradi nor T. guianense and a comparison with other venzuelan Trichomycterus species showed that there are two species in the Guacharo cave, both of them undescribed. These species may be close to Trichomycterus nigricans.

Synonyms

None.

Country

Venezuela

Types

This species has not been described so there are no types.

Distribution

Probably known only from the Guacharo Cave.

Conservation Status

TLO [NE]

Key References

Schulz, L. Journal Article 1949 A further contribution to the ichthyology of Venezuela
Bellard Pietri, E. Journal Article 1957 El Guacharo
Bellard Pietri, E. Journal Article 1960 La Cueva del Guacharo
Nalbant, T. T. and Linares, O. Book Section 1987 A study of a subterranean population of Trichomycterus guianense (Eigenmann, 1909) from Venezuela (Pisces, Siluriformes, Trichomycteridae)
Romero, A. Journal Article 1987 Observaciones preliminares sobre la conducta en individuos cavernicolas de Trichomycterus conradi (Pisces: Trichomycteridae)
Andreani, L.E. Thesis 1987 Estudio comparativo de dos poblaciones de Trichomycterus sp. (Siluriformes, Trichomycteridae) procedentes de la Cueva del Guacharo y de la Quebrada de Cerro Negro, Estado Monagas
Andreani, L.E. Journal Article 1990 Estudio comparativo de dos poblaciones, una hipogea y otra epigea, de Trichomycterus sp. (Siluriformes, Trichomycteridae) (incluye un alanysis de sus dietas)
Perez, J. E. and Moodie, G. E. E. Journal Article 1993 Genetic variation in a cave-dwelling Venezuelan catfish
Brosset, A. Book Section 1998 Aves
DoNascimiento, C. and Villarreal, O. Journal Article 2005 Estatus taxonómico y sistemático de la población de bagres tricomictéridos de la cueva del Guácharo (Otophysi, Siluriformes).
Colihueque, N., Corrales, O, and Yáñez, M. Journal Article 2017 Morphological analysis of Trichomycterus areolatus Valenciennes, 1846 from southern Chilean rivers using a truss-based system (Siluriformes, Trichomycteridae)