Peckoltia vermiculata ( Steindachner, 1908 )

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 : 37-40

Peckoltia vermiculata ( Steindachner, 1908)

Fig. 20

Ancistrus vittatus vermiculata Steindachner, 1908: 166 . Type locality: dem mittleren Laufe des Amazonestrommes , den Gewässern um Pará, Brasiliens. Syntypes: NMW 48056 (1), NMW 48059 (1), NMW 48064 (1). Originally as Ancistrus vittatus var. vermiculata .

Material Examined: All syntypes, BRAZIL, Pará, no other locality information available: NMW 48056, 1 , 107.9 ; NMW 48059, 1 , 74.7 ; NMW 48064, 1 94.9.

Diagnosis: Peckoltia vermiculata can be identified from all other Peckoltia by having vermiculate lines radiating from a central point on the parieto-supraoccipital. Other Peckoltia with dark vermiculations on the head are P. braueri , P. caenosa , P. cavatica , and P. lineola , none of which have the vermiculations radiating from a central point. Peckoltia vermiculata can be further separated from P. braueri by lacking vermiculations on the compound pterotic; from P. cavatica by having markings across the bones and plates of the head (vs. just outlining the bones and plates); from P. caenosa by lacking markings on the abdomen (vs. having vermiculations), and by having dark bands at least on the caudal fin (vs. small white spots); and from P. lineola by having the vermiculations narrower than the pupil (vs. wider than the pupil) and by lacking spots on the abdomen (vs. spots combining to form longitudinal lines).

Description. Morphometrics in Table 5, counts based on three individuals. Largest specimen examined 107.9 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 mediumsized.

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 structure. A pair of lateral plates converging at midline between anus and exposed first anal-fin pterygiophore. 25– 26 (mode 26) 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 28–35, 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 five dorsal procurrent caudal-fin rays and four to five (mode four) 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 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 acute angle, premaxillaries forming gentle arc less than 135°. Teeth with small, moderately wide cusps, lateral cusp approximately half length of medial cusp, stalk of tooth long; seven to 10 dentary teeth (no mode available), nine premaxillary teeth.

Color: Color of all specimens faded. Base color light tan with slightly darker markings. Four dorsal saddles weakly evident on 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. The first two saddles might combine midbody. Anterior body plates may have been outlined with darker pigment. Head with short, dark lines radiating from central point on parietosupraoccipital, lines narrower than pupil diameter; snout with small spots or spots combining to form network of vermiculations; spots mostly separate below eye and on compound pterotic, dorsal process of cleithrum, and first column of lateral plates. Dorsal and pectoral fins dark, pelvic fins with faint bands, caudal with 3–5 bands. Abdomen without markings. Lower surface of caudal peduncle tan.

Sexual Dimorphism: None observed.

Range. Locality only given as Pará, Brazil.

Figures

FIGURE 20. Dorsal, lateral, and ventral views of the syntype of Peckoltia vermiculata NMW 48056, 107.9 mm SL. Photographs by J.W. Armbruster.