| Sarcoglanidinae | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Siluriformes |
| Family: | Trichomycteridae |
| Subfamily: | Sarcoglanidinae Myers & Weitzman, 1966 |
| Type genus | |
| Sarcoglanis Myers & Weitzman, 1966 |
|
| Genera | |
|
Ammoglanis |
|
Sarcoglanidinae is a subfamily of catfishes (order Siluriformes) of the family Trichomycteridae. It includes six genera, Ammoglanis, Malacoglanis, Microcambeva, Sarcoglanis, Stauroglanis, and Stenolicmus.[1][2]
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Sarcoglanidinae was first established in 1966 for Sarcoglanis simplex and Malacoglanis gelatinosus. A third species of the subfamily, Stauroglanis gouldingi, was described about 25 years later.[3] Descriptions of additional species have followed, though most genera remain monotypic.[4] The relationships of the genus Ammoglanis with other sarcoglanidines are not well-established; however, this genus is currently included within Sarcoglanidinae.[5]
This subfamily has been proposed to have a sister group relationship to Glanapteryginae. Like the members of this subfamily, many glanapterygines are sand-dwelling fish.[6]
All genera except Microcambeva are endemic to the Amazon River; Microcambeva species are known from southeastern Brazil.[2] Despite their scarcity in museum collections, it has been suggested that it is possible that sarcoglanidines occur throughout the entire Amazon basin as well as the Orinoco basins.[3]
Sarcoglanidines usually live in sandy banks of rivers and streams.[2] They are sand-dwellers that feed on minute arthropods.[4]
Sarcoglanidines are all very small (to the extent of some species being considered miniaturized), usually not exceeding 25 millimetres (1.0 in) SL; Microcambeva ribeirae is the largest species, reaching 48 mm (1.9 in) SL.[2] All except one species are poorly pigmented, with a translucent body in life.[2] The three pairs of barbels present in other trichomycterids are also present in these fish, though nasal barbels tend to be reduced. In addition, some taxa have barbel-like structures on the ventral surface of the head.[2] Sarcoglanis simplex and Malacoglanis gelatinosus possess an uncommonly deep body, a hypertrophied sac-like adipose organ above the pectoral fin, and the absence of premaxillary teeth. These two species along with Stauroglanis gouldingi have few or no opercular and interopercular odontodes.[2]
The subfamily has been characterized, among other things, by a toothless upper jaw, the presence of an adiposelike fin, and the pectoral-fin rays projecting beyond the fin membrane.[3]