Comprehensive DescriptionRead full entry
This genus is distributed east of the Andes on nearly the entire subcontinent. Species occur in a variety of habitats from the main flow of rivers on sandy and rocky bottoms to flooded areas and lakes over muddy and sandy bottoms. Sexual dimorphism includes hypertrophied development of the pectoral spines, blunt odontodes on the pelvic and anal fin spines, and tooth crowns becoming shortened and rounded in mature males ( Isbrùcker 1981b). Males are abdomino-lip brooders. Loricaria ZBK is the nominal genus of the family. Phylogenetic relationships within Loricaria ZBK and among other members of Loricariini remain uncertain. Its external morphology shows few shared derived characters, making comparison with other genera difficult. Loricaria ZBK has been hypothesized to occupy a basal position among members of the subtribe Loricariina , with the other genera possessing derived characters. Based on the characteristics of its mouth, Loricaria ZBK appears to maintain a close relationship with representatives of the Pseudohemiodon ZBK group. This hypothesis has been proposed in the studies of Rapp Py-Daniel (1997) and Montoya-Burgos et al. (1998), in which Loricaria ZBK maintained a sister relationship to the Pseudohemiodon ZBK group. However, these authors did not resolve relationships among species of the Loricaria ZBK group. Kavalco et al. (2005) reported karyotypic diversity ranging from 2n = 62 to 2n = 68 for the four species characterized. Under the impression that the original syntypes were lost, Isbrücker (1972) established a neotype for L. cataphracta ZBK (ZMA 109.616). Between 1972 and 1981, Isbrücker learned that the two syntypes did in fact exist and are currently housed at the Swedish Museum of Natural History in Stockholm. Based on a photograph of two syntypes, Isbrùcker (1981b) designated one as the lectotype (NRM 33). The rediscovery of these syntypes invalidated the previous neotype according to the ICZN (1999), article 75.8. The disposition of the lectotype according to Eschmeyer (1998), which is based on Wheeler (1989), is Zoological Museum, University of Copenhagen (ZMUC 27). However, Wheeler (1989: pp. 214-215) confirmed Isbrücker ’s designation of the lectotype: “Two loricariid specimens from the collection of King Adolf Fredrik, one of which has been designated as the lectotype of L. cataphracta ZBK by Isbrücker (1981), are preserved in the Swedish Museum of Natural History, Stockholm. This specimen was certainly the specimen which Linnaeus used for the major source material of his description (Fernholm & Wheeler, 1983)”. Moreover, concerning specimen ZMUC 27 deposited in Copenhagen, Wheeler (1989: p. 215) concluded: “It thus seems certain that this specimen is not one of those referred to by Linnaeus (1758) in his diagnosis of the species, or its variety beta ”. Loricaria ZBK was revised by Isbrücker (1981b) who recognized eleven valid species. For lack of clear diagnostic features, Proloricaria Isbruecker , 2001 ZBK is herein considered a junior synonym of Loricaria ZBK . A twelfth species has been described from North-East of Argentina by Rodríguez & Miquelarena (2003).