Three catfish described from Amazon basin

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Three new species of whiptail catfishes in the genus Loricaria have been described from large white- and black-water river channels of the Amazon basin of Brazil, the upper Rio Negro drainage of southern Venezuela, and clear waters of the lower Tocantins River.

Loricaria lundbergi, L. pumila and L. spinulifera were named in the latest issue of the journal Neotropical Ichthyology by Matthew Thomas and Lucia Py-Daniel.

Loricaria lundbergiLoricaria lundbergi is distinguished from congeners in having a combination of the following: abdominal plate development confined to the pre-anal shield and posterior median abdominal area, pectoral girdle mostly naked, and with isolated clusters of plates near bases of pectoral fins posterior to gill openings often present in adults, head width 17.6"18.4% of standard length, length of basicaudal plate 9.0"11.9% of head length, and the body marked with conspicuous dark saddles and fins with solid dark pigment.

This species is known from the Rio Negro drainage, and the stomach contents of a single dissected specimen contained aquatic insect larvae (order Diptera, family Chironomidae), sclerotized body parts of unidentified insect larvae, organic detritus and sand.

Loricaria pumilaLoriacria pumila is distinguished from congeners except L. nickeriensis by attaining a small adult size, reaching sexual maturity at less than 80 mm SL. It can be distinguished from Loricaria nickeriensis and Amazon basin congeners by the following combination of characters: prominent crests on surfaces of head and predorsal plates with numerous well developed odontodes arranged in conspicuous linear rows, anterior abdominal area covering pectoral girdle naked, with occasional small isolated plates at bases of pectoral fins, pre-anal shield and space between lateral abdominal plates with large polygonal plates, 31"32 total lateral plates, and 18"19 post-anal plates.

This species is known from the Amazon River near the mouth of the Tapajs and Par rivers adjacent to and including lower Tocantins River.

The stomach contents of a single dissected specimen contained an entire aquatic insect larva (order Coleoptera), sclerotized body parts of unidentified insects, organic detritus and sand.

Loricaria spinuliferaLoricaria spinulifera is distinguished from all congeners by the following unique characters: strongly developed crests on surfaces of head and predorsal plates bearing large thorn-like odontodes, a unique arrangement of oral papillae situated behind the premaxillary teeth consisting of approximately 20 papillae, all longer than premaxillary teeth, arranged in a dense cluster, a unique arrangement of plates on the median abdominal area consisting of small round to diamond-shaped plates varying in size and spacing, with pre-anal shield absent or with few small plates distributed along the centre and around anterior margin of anus, and a unique pigment pattern on the dorsal surface of the head consisting of solid dark brown extending from centre of orbits to tip of snout with large irregular spots from centre of orbits to middle of dorsal fin.

It is known from the Rio Negro, and from the lower Branco River downstream to the mouth of the Rio Negro, including the lower Jauaperi River; stomach contents of a single dissected specimen contained sclerotized body parts of aquatic insect larvae of the orders Trichoptera and Diptera, as well as organic detritus and sand.

For more information, see the paper: Thomas, MR and LHR Py-Daniel (2008) Three new species of the armored catfish genus Loricaria (Siluriformes: Loricariidae) from river channels of the Amazon basin. Neotropical Ichthyology 6, pp. 379"394.