Editorial Type:
Article Category: Research Article
 | 
Online Publication Date: 30 Mar 2012

Review of the Genus Cathorops (Siluriformes: Ariidae) from the Caribbean and Atlantic South America, with Description of a New Species

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Page Range: 77 – 97
DOI: 10.1643/CI-10-202
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The New World genus Cathorops in the family Ariidae (Sea Catfishes) includes species that inhabit estuarine and coastal waters as well as freshwaters, playing an important role in Neotropical coastal and estuarine fisheries. The relatively conserved external morphology coupled with the marked sexual dimorphism and ontogenetic variation makes it difficult to recognize and diagnose the species. One of the major problems concerns the nomenclatural and geographical limits of C. spixii, described from tropical Brazil and often treated as the only coastal marine species in the genus from the Western Atlantic. Examination of types of nominal species as well as comprehensive collections of non-types from Caribbean and Atlantic South America, lead us to conclude that C. spixii is restricted to Brazil and that C. nuchalis is a valid species, ranging from Venezuela to Guyana. The nominal species Arius laticeps, Arius nigricans, and Arius variolosus are synonyms of C. nuchalis, C. spixii, and C. arenatus, respectively. We also describe a new species in the Cathorops mapale species group from Colombia and Venezuela.

Copyright: 2012 by the American Society of Ichthyologists and Herpetologists
Fig. 1.
Fig. 1.

Body in lateral view and head in dorsal view. (A) Arius nuchalis, syntype, BMNH 1975.1.17.1-2, 68.5 mm SL, and (B) A. laticeps, syntype, BMNH 1976.2.25.1, male, 110.5 mm SL.

Fig. 2.
Fig. 2.

Plot of width of the supraoccipital process at the posterior end versus standard length for Cathorops agassizii, C. nuchalis, and C. spixii (A), and orbital diameter versus caudal peduncle height for Cathorops nuchalis and C. arenatus (B).

Fig. 3.
Fig. 3.

Plot of supraoccipital process length versus maxillary barbel length for C. nuchalis and C. spixii (A), and supraoccipital process length versus standard length for Cathorops arenatus, C. nuchalis, and C. wayuu (B).

Fig. 4.
Fig. 4.

Tooth plates of Cathorops nuchalis (A), C. spixii (B), and C. wayuu (C). Abbreviations: atp–accessory tooth plates; Den–dentary; pe–posterior expansion; PMtp–premaxillary tooth plate. Scale bar  =  2 mm.

Fig. 5.
Fig. 5.

Sampling localities of examined material. Filled symbols represent type specimen localities; open symbols represent non-type specimen localities. Some symbols indicate more than one locality or lot of specimens.

Fig. 6.
Fig. 6.

Body in lateral view and head in dorsal view. (A) Cathorops spixii, neotype, MZUSP 49345, female, 119.0 mm SL, (B) C. arenatus, non-type, MZUSP 104013, female, 125.5 mm SL, and (C) profile of osseous portion of dorsomedial groove. Abbreviation: SOp–supraoccipital process.

Fig. 7.
Fig. 7.

Plot of orbital diameter versus maxillary barbel length for Cathorops agassizii and C. spixii (A), and orbital diameter versus width of cephalic shield at lateral ethmoid area for Cathorops arenatus, C. spixii, and C. wayuu (B).

Fig. 8.
Fig. 8.

Body in lateral view and head in dorsal view. (A) Arius nigricans, holotype, MNHN 0000-0176, 142 mm SL, and (B) A. variolosus, holotype, MNHN 0000-4169, 142 mm SL.

Fig. 9.
Fig. 9.

Body in lateral view and head in dorsal view. (A) Cathorops wayuu, holotype, INV-PEC 8247, 232.8 mm SL (fresh specimen).

Fig. 10.
Fig. 10.

Scatterplots of principal components PC1 and PC2, obtained from the analysis of six morphometric and two meristic variables for Cathorops mapale (M–holotype, m–paratypes) and C. wayuu (W–holotype, w–paratypes). Factor loadings on the first and second principal components.

Contributor Notes

Associate Editor: R. E. Reis.

Received: 24 Dec 2010
Accepted: 07 Nov 2011
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