Pterygoplichthyini

Pterygoplichthyini
Pterygoplichthys sp.
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Family: Loricariidae
Subfamily: Hypostominae
Tribe: Pterygoplichthyini
Armbruster, 2004
Genera

H. annectens group
Pterygoplichthys

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. 1 2 3 4 5 6 Armbruster, Jonathan W. "Pterygoplichthyini Armbruster 2004". Retrieved 2007-08-08.
  2. "Modifications of the Digestive Tract for Holding Air in Loricariid and Scoloplacid Catfishes" (PDF). Copeia (3): 663–675. 1998. doi:10.2307/1447796.
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