Peckoltia

Armbruster, Jonathan W., 2008, The genus Peckoltia with the description of two new species and a reanalysis of the phylogeny of the genera of the Hypostominae (Siluriformes: Loricariidae), Zootaxa 1822 (1), pp. 1-76 : 5-7

Peckoltia Miranda Ribeiro (1912)

Peckoltia Miranda Ribeiro, 1912:7. Type species: Chaetostomus vittatus Steindachner, 1881 .

Peckoltichthys Miranda Ribeiro 1917:49. Type species: Peckoltichthys filicaudatus Miranda Ribeiro, 1917.

Sophiancistrus Isbrücker & Seidel 2001 (in Isbrcker, et al., 2001):21. Type species: Hemiancistrus ucayalensis Fowler, 1940 .

Species Included:

Hemiancistrus arenarius Eigenmann and Allen 1942 (synonym of P. bachi )

Chaetostomus bachi Boulenger 1898

Hemiancistrus braueri Eigenmann 1912

Hemiancistrus brevis La Monte, 1935

Peckoltia caenosa new species

Peckoltia cavatica Armbruster and Werneke 2005

Peckoltichthys filicaudatus Miranda Ribeiro1917 (synonym of P. bachi )

Chaetostomus furcatus Fowler 1940

Peckoltichthys kuhlmanni Miranda Ribeiro 1920 (synonym of P. vittata )

Peckoltia lineola new species

Ancistrus multispinis Holly 1929

Chaetostomus oligospilus Günther 1864

Hemiancistrus ucayalensis Fowler 1940 (synonym of P. bachi )

Chaetostomus vittatus Steindachner 1881 (type species of Peckoltia )

Chaetostomus vittatus vermiculata Steindachner 1908 (recognized as Peckoltia vermiculata )

Diagnosis: Peckoltia cannot be diagnosed by any synapomorphies and is likely a paraphyletic assemblage. In the phylogenetic analysis below, it was not monophyletic; however, there are no clues as to how Peckoltia should either be split or combined with other genera, support for nodes around the species of Peckoltia are weak, and Peckoltia is recognized through the set of comparisons that follow. Peckoltia can be diagnosed from all other loricariids except members of the Ancistrini and Pterygoplichthyini by having hypertrophied cheek odontodes on plates that can be everted greater than 75° from the head. Peckoltia can be identified from the Pterygoplichthyini by lacking a modified stomach (vs. having the stomach connected to the dorsal abdominal wall by a connective tissue sheet (see Armbruster, 1998b; 2004); from Pterygoplichthys by having seven dorsal-fin rays (vs. nine or more); and from the Hemiancistrus annectens group by having more than ten hypertrophied cheek odontodes in adults (vs. usually three or less although up to nine). Peckoltia can be identified from all other ancistrins except Exastilithoxus , Hypancistrus , Leporacanthicus , Lithoxus , Megalancistrus , Panaque and Spectracanthicus by having the dentaries forming angle of ~90° or less ( Fig. 1 ); from Exastilithoxus , Leporacanthicus , and Lithoxus by having oval lips (vs. round lips), and by having a very deep body (vs. dorsoventrally flattened); from Exastilithoxus by lacking fimbriae along the lower lip; from Leporacanthicus by lacking fimbriae above the upper lip; from Leporacanthicus , Megalancistrus , and Pseudacanthicus by having three plates between the head and the dorsal fin (vs. four or more, nuchal plate is included), by lacking sharp keel odontodes, by having viliform (vs. stout) teeth; from Hypancistrus by having the teeth in the dentary and premaxilla of about equal size (vs. dentary teeth almost twice as long as premaxillary teeth); from Panaque by having viliform teeth (vs. spoon-shaped or elongate, spatulate teeth); from Panaque (Panaqolus) by always having at least a small buccal papilla (vs. buccal papilla absent); from Spectracanthicus by having the dorsal and adipose fins separate (vs. posterior membrane of the dorsal fin expanded such that it contacts at least the preadipose plate and usually the adipose-fin spine), by usually lacking odontodes on the opercle as adults (vs. odontodes present), and by having a pattern of dorsal saddles (vs. either all dark or dark with white to yellow spots); and from Spectracanthicus murinus by having evertible cheek plates with hypertrophied odontodes.

Adult Peckoltia (except some P. bachi ) have no odontodes on the opercle, a trait shared among the ancistrins with Baryancistrus , Hemiancistrus , Hypancistrus , Panaque , and Parancistrus . In addition to the shortened, angled jaws, Peckoltia can be identified from Baryancistrus and Parancistrus by having the posterior membrane of the dorsal fin short and the dorsal and adipose fins separate (vs. posterior membrane of the dorsal fin expanded such that it contacts at least the preadipose plate in all except B. longipinnis , where the membrane is only expanded); from Baryancistrus , Hemiancistrus , and Parancistrus by usually having a pattern of dorsal saddles with spots, if present, just on the head and ventral surface (vs. dark or light spots present behind the head and saddles absent; this works for all except P. bachi , P. oligospila and some P. furcata ); and from Parancistrus by having restricted gill openings (vs. large gill openings), and having the body deep and narrow (vs. wide and dorsoventrally flattened). Peckoltia oligospila and P. furcata can be further separated from Baryancistrus , H. chlorostictos , H. fuliginosus , H. guahiborum , H. macrops , H. meizospilos , H. subviridis , H. votouro , and Parancistrus by having dark spots (vs. with light spots or uniformly dark); and from H. medians by lacking keels anterodorsally (vs. short keels present). Peckoltia oligospila can be identified from H. punctulatus and H. megalopteryx by having less than 25 teeth per jaw ramus (vs. 40 or more). Peckoltia furcata can be identified from H. punctulatus by having a strongly forked caudal fin (vs. caudal fin emarginate) and from H. punctulatus and H. megalopteryx by having bands in the caudal fin (vs. spots or uniformly dark).

Figures

FIGURE 1. Ventral view of mouths of A. Hemiancistrus snethlageae MCP 15151, 132.8 mm SL, and B. Peckoltia lineola, MCNG 55684, holotype, 88.1 mm SL. Lines are representations of the orientations of the dentaries and the approximate angle for these fishes is provided.