Peckoltia lineola, Armbruster, 2008

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 : 29-32

Peckoltia lineola new species

( Figs. 2e and 16 )

Holotype: MCNG 55684 , VENEZUELA, Amazonas, Río Orinoco drainage, 88.3, Río Ventuari , 23 km NE of Macuruco, 94 km E of San Fernando de Atabapo, 04°04’50”N, 66°51’55”W, N.K. Lujan, D.C. Werneke, M.H. Sabaj, L.S. de Souza, and O. Leon, 5 April 2004.

Paratypes: COLOMBIA, Guainia, Río Orinoco drainage: ICNMNH 9910 , 2 , 37.1 – 57.5 , Inirida, Caño Bocon - Río Inirida, M. T. Sierra and M. Patiño, February - March 2004 . VENEZUELA, Amazonas, Río Orinoco drainage: ANSP 185222 , 2 , 1 cs, 88.3–92.5, AUM 39245 2, 1 cs, 88.3–94.7, and MCNG 55685 , 2 , 83.8 – 96.9 , same data as holotype ; AUM 41561, 1 (not measured), 41.1, Río Manapiare, at Laja Pelada landing, 27 km SSW of San Juan de Manapiare, Río Ventuari basin, 05°07’27”N, 66°05’48”W, O. Leon, D.C. Werneke, and N.K. Lujan, 18 April 2004 ; MCNG 37054 , 1 , 58.3 , Río Manipiare, 5–6 km above mouth, Río Ventuari basin, K. Winemiller, L. Nico, S. Walsh, and A. Barbarino, 15 January 1998 .

Diagnosis: Peckoltia lineola can be identified from all other Peckoltia except P. braueri , P. caenosa , P. cavatica , and P. vermiculata by having vermiculations on the head and snout. Peckoltia lineola can be identified from P. braueri , P. cavatica , and P. vermiculata by having thick vermiculations almost as wide as the pupil on the compound pterotics and snout (vs. thin vermiculations much narrower than the pupil diameter and by also having large spots on the compound pterotics and snout (vs. no spots); from P. braueri and P. cavatica by lacking an orange band in the dorsal fin; from P. cavatica by having the vermiculations cross the bones like the compound pterotic (vs. dark lines only outlining the plates and bones of the head); from P. caenosa by having dark bands in the fins (vs. light spots), by having long, thick, longitudinal lines on the abdomen (vs. vermiculations with a random orientation), by having the light interspaces on the snout of about the same width of the black spots and lines (vs. light vermiculations narrower than dark ones), and by having the light bands of the caudal at least 50% width of dark bands (vs. 25%); and from P. vermiculata by not having the vermiculations coming from a central point on the parieto-supraoccipital. Peckoltia lineola is similar to P. brevis except that some of the spots on the head and snout combine to form lines (vs. all spots separate) and the spots on the abdomen combine to form long, thick longitudinal lines (vs. spots separate).

Description: Morphometrics in Table 4, counts based on eight individuals unless otherwise stated. Largest specimen examined 96.9 mm SL. Body stout, fairly wide. Head gently sloped to parieto-supraoccipital. Parieto-supraoccipital with tall, rounded crest. Parieto-supraoccipital crest barely raised above nuchal region. Nuchal region rises slightly to nuchal plate. Dorsal profile sloped ventrally to dorsal procurrent caudal-fin spines, then rising rapidly to caudal fin. Ventral profile flat to ventral procurrent caudal-fin spines and then sloping ventrally to caudal fin. Supraorbital ridge rounded, contiguous, but slightly offset medially from rounded ridge proceeding from anterior margin of orbit to anterolateral corner of anterior nare. Head contours smooth. Eye medium-sized.

Keels absent. Mid-ventral plates bent at their midline above pectoral fin to form ridge. Dorsal plates bent dorsally below dorsal fin to form ridges that converge at preadipose plate, dorsal surface flat between ridges. Five rows of plates on caudal peduncle. Abdomen covered in small plates except for small naked areas posterior to lower lip and at insertions of paired fins. First anal-fin pterygiophore exposed to form a platelike struc- ture. A pair of lateral plates converging at midline between anus and exposed first anal-fin pterygiophore. 24– 26 (mode 24) plates in the median series.

Frontal, infraorbitals, nasal, compound pterotic, sphenotic, and parieto-supraoccipital, supporting odontodes; opercle supporting odontodes in juveniles but not in adults, posterodorsal corner of opercle covered by one or two plates in adults. Odontodes on lateral plates not enlarged to form keels. Hypertrophied cheek odontodes 19–26 (N=5), longest almost reaching first mid-ventral plate in adults. Cheek plates evertible to approximately 90° from head. Odontodes on tip of pectoral-fin spine slightly hypertrophied.

Dorsal fin short, reaching preadipose plate fin when adpressed; dorsal-fin spine same length as proceeding rays making edge straight. Dorsal-fin spinelet V -shaped, dorsal-fin spine lock functional. Dorsal fin II,7. Adipose fin with one preadipose plate and fairly long spine. Caudal fin forked, lower lobe longer than upper, I,14,I with four to five (mode four) dorsal procurrent caudal-fin rays and four to five (mode five) ventral procurrent-fin rays. Anal fin short with unbranched ray weak and approximately same length of first branched ray. Anal fin I,4, Pectoral-fin spine almost reaching just beyond pelvic fin when adpressed ventral to pelvic fin. Pectoral fin I,6. Pelvic fin reaching to posterior insertion of anal-fin when adpressed. Pelvic fin I,5.

Iris operculum present. Flap between anterior and posterior nares short. Lips wide, fairly thin. Upper lip with small, round papillae. Lower lip with small papillae anteriorly and posteriorly, becoming larger medially. Maxillary barbel short, maximally reaching base of evertible cheek plates. Buccal papilla small. Jaws narrow, dentaries forming very acute angle, premaxillaries forming angle of 90° to slightly greater than 90°. Teeth with small, moderately wide cusps, lateral cusp approximately half length of medial cusp, stalk of tooth long; 10–16 dentary teeth (N=6, mode 13), 10–19 premaxillary teeth (N=6, mode 12).

Color: Base color light tan with brown to black markings. Four dorsal saddles on the body, the first below the middle rays of the dorsal fin, the second below the posterior rays of the dorsal fin and slightly posterior, the third below the adipose fin and slightly anterior, and the fourth at the end of the caudal peduncle. Third and fourth bars may have anterior extensions or have an anterior projection making them h -shaped. Fourth bar combines with first band of caudal dorsally. The first two saddles combine midbody. All fins with dark bands with dark and light areas ranging from approximately equal width to dark bands wider, caudal bands may be irregular. Number of bands increases with size. Dark spot present between dorsal-fin spinelet and spine. Abdomen with large spots that combine to form thick longitudinal lines (usually one almost continuous central line and lines on each side). Lower surface of caudal peduncle with dark blotches formed from the lower extensions of the third and fourth dorsal saddle, the anterior extensions of the third and fourth saddles, and accessory blotch between the third and fourth saddles. Juveniles colored as adults, but without anterior extensions of the third and fourth dorsal saddles, without spots on the abdomen, and with the spots and lines on the head less numerous.

Sexual Dimorphism: The main collection consists of only nuptial males. Nuptial males with hypertrophied odontodes on sides and posterior part of head; hypertrophied odontodes becoming larger posteriorly. Hypertrophied odontodes on upper caudal-fin spine and adipose spine. Upper caudal-fin spine thickened. Odontodes on pectoral-fin spine not noticeably larger.

Range. Known from the Río Ventuari of Venezuela and the Río Iniridá of Colombia ( Fig. 8 ).

Habitat. Specimens collected in Venezuela were from rocky riffles.

Etymology: Lineola is Latin for little line, refers to the short lines on the compound pterotic.

Figures

FIGURE 2. Live pictures of A. Peckoltia bachi, AUM 45592, B. Peckoltia braueri, AUM 38882, C. Peckoltia brevis, D. Peckoltia cavatica, UG/CSBD 11043, holotype, E. Peckoltia lineola, paratype, F. Peckoltia vittata, AUM 39313. Photographs by N.K. Lujan (A) and M.H. Sabaj (B-F).

FIGURE 8. Distribution of Peckoltia braueri (triangles), P. caenosa (circles), P. cavatica (squares) and P.lineola (diamonds). Open symbols are type localities; the type locality for P. braueri is not adequate to plot on the map. Symbols may represent more than one locality

FIGURE 16. Dorsal, lateral, and ventral views of the holotype of Peckoltia lineola MCNG 55684, 88.1 mm SL. Photographs by J.W. Armbruster.