Cladus: Eukaryota Pterygoplichthyini is a tribe of catfishes (order Siluriformes) of the family Loricariidae. It includes two genera, Pterygoplichthys and the currently undescribed genus referred to as the Hemiancistrus annectens group.[1] This group was earlier misspelled as Pterygoplichthini.[1] Pterygoplichthyines are known from nearly the entire range of loricariids except for the Guyanas and coastal streams in southeastern Brazil.[1] Pterygoplichthyini is sister to the tribe Ancistrini, which shares the derived presence of an evertible patch of plates on the cheek.[1] Pterygoplichthys and the H. annectens group differ most obviously in the number of dorsal fin rays (7 in the H. annectens group and 9+ in Pterygoplichthys).[1] The two genera are supported as sisters by only one derived characteristic: a modified stomach that is attached to the abdominal wall by a net of connective tissue.[1] This modified stomach allows these fish to breathe air. The stomach is vascularized. A white net of connective tissue surrounds the organ, leaving a circular area in the middle of the stomach free; this connective tissue firmly holds the stomach to the body wall and is better developed in adults. It may also function as a hydrostatic organ, allowing the fish to remain buoyant midwater.[2] References 1. ^ a b c d e f Armbruster, Jonathan W.. "Pterygoplichthyini Armbruster 2004". http://www.auburn.edu/academic/science_math/res_area/loricariid/fish_key/ptergrp/ptergrp.html. Retrieved 2007-08-08.
Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License |
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