Peckoltia ephippiata Armbruster, Werneke & Tan

Armbruster, Jonathan W., Werneke, David C. & Tan, Milton, 2015, Three new species of saddled loricariid catfishes, and a review of Hemiancistrus, Peckoltia, and allied genera (Siluriformes), ZooKeys 480, pp. 97-123 : 100-102

Taxon classification Animalia Siluriformes Loricariidae

Peckoltia ephippiata Armbruster, Werneke & Tan sp. n. Fig. 2, Table 2

Type locality.

Brazil, South America

Holotype.

MCP 35627, 1, 101.7 mm SL, BRAZIL, Rôndonia, Presidente Médici. rio Madeira dr., rio Leitão on highway BR-364, about 5 km N of Presidente Médici, -11.1328°, -061.9008°, 15 Jul 2004, R.E. Reis, P.C. Lehmann, F.C. Lima, and E.H.L. Pereira.

Paratypes.

ANSP 197614, 2, 60.4-92.5, AUM 65116, 2, 64.1-96.4, MCP 48395, 13, 48.2-97.7, MNRJ 42662, 2, 66.0-89.7, UF 237091, 2, 55.6-82.6, same locality data as holotype.

Diagnosis.

Peckoltia ephippiata can be separated from Peckoltia pankimpuju by having well developed color and eyes; from all other Peckoltia by having no spots or bands in the dorsal fin; from all except Peckoltia greedoi by having small, very faint spots on the head (vs. large spots, mottling, short lines, or thick dark areas, always much more intense than the weak spots in Peckoltia ephippiata ; Peckoltia greedoi has a uniformly dark head, but the small faint spots of Peckoltia ephippiata can appear uniformly dark without closer inspection); from all Peckoltia except Peckoltia furcata , Peckoltia greedoi , Peckoltia lujani , Peckoltia pankimpuju , and Peckoltia sabaji by having the dentaries meet at an angle greater than 90°; from Peckoltia greedoi and Peckoltia lujani by lacking bands in the dorsal fin, rays light and membranes dark (vs. bands present), by having more teeth ( Peckoltia ephippiata : 39-72 dentary, 41-73 premaxillary; Peckoltia greedoi : 16-39 dentary, 20-38 premaxillary; Peckoltia lujani : 20-37 dentary, 23-45 premaxillary), by having slight keels on the lateral plates, particularly the median series (vs. keels absent), and by having platelets on the central region of the abdomen posterior to the pectoral girdle present (vs. platelets maximally present below pectoral girdle and in a narrow, lateral column just posterior to pectoral fin, and below pelvic girdle); and from Peckoltia lujani by having the pectoral-fin spine relaxed position angled dorsally, pointing at insertion of dorsal fin (vs. pectoral-fin spine angled only slightly dorsally, pointing maximally to dorsal insertion of caudal fin) and by the pectoral-fin spine reaching two or more plates of the ventral series beyond the pelvic base when adpressed ventral to pelvic fin (vs. less than one plate).

Peckoltia ephippiata differs from Etsaputu by having greater than six evertible cheek odontodes, the largest of which extends posterior to the eye (vs. six or fewer, the largest not extending beyond the exposed portion of the opercle). Peckoltia ephippiata can be separated from Hemiancistrus (except ' Hemiancistrus ' landoni ) and Ancistomus by having prominent dorsal saddles (vs. dark or light spots or entirely dark); and from all Hemiancistrus and Ancistomus by having bands in the caudal fin and no free spots (vs. bands absent or present with some free spots). Peckoltia ephippiata can be separated from Peckoltichthys bachi by having small, faint spots on the head (vs. large dark spots or mottling); by having the eyes high on the head with the dorsal rim of the orbit higher than the interorbital space (vs. low on the head, dorsal rim of orbit lower than interorbital space), and by having small plates on the abdomen (vs. relatively large).

Description.

Morphometrics in Table 2. Counts and measurements based on 18 specimens. Largest specimen examined 101.7 mm SL. Body moderately elongate. Head and nape forming arc from tip of snout to insertion of dorsal fin. Dorsal slope decreasing in straight line to insertion of dorsal procurrent caudal rays then ascending to caudal fin. Body depth greatest below insertion of dorsal fin. Ventral profile flat to caudal fin. Caudal peduncle triangular in cross section with dorsal surface flattened. Body widest at insertion of pectoral fins, narrowest at insertion of caudal fin. Snout rounded.

Eye moderately sized, dorsal rim of orbit forming tall crest that continues forward to area just anterior of nares as low, rounded ridge. Iris operculum present. Interorbital space largely flat, but with slight, rounded, median hump that is contiguous with rounded ridge on snout formed from mesethmoid. Parieto-supraoccipital pointed posteriorly with the posterior point raised above nuchal region in small crest. Infraorbitals, frontal, nasal, compound pterotic, and parieto-supraoccipital supporting odontodes. Preopercle not supporting odontodes. Opercle generally covered by plates and not supporting odontodes although one to four may be present, particularly in smaller individuals.

Lips covered with short, wide papillae. Lower lip wide, upper lip narrow. Edge of lower lip with small crenulae. Maxillary barbel only barbel present, reaching about one third of distance to gill opening.

Median plates 25-26 (mode 26). Plates unkeeled, but first four or five plates of mid-ventral series bent to form slight ridge. Five caudal peduncle plate rows. Plates on all dorsolateral surfaces of body except for extreme edge of snout that only has a narrow column of platelets on either side of the snout tip. Throat mostly covered in platelets except for area right below lower lip. Abdomen covered in platelets except for broad region just anterior to level of pelvic-fin spine insertions, laterally below pelvic girdle, and small region around anus. Evertible cheek plates supporting hypertrophied odontodes that can be everted perpendicular to head. Cheek odontodes 18-40 (mode 32). Longest evertible cheek odontode reaching to about level of posterior edge of pectoral-fin spine. Hypertrophied cheek odontodes relatively weak. Odontodes slightly longer than average body odontodes present along dorsal-, adipose-, pelvic-, caudal-, and pectoral-fin spines; larger individuals with hypertrophied odontodes at tip of pectoral spine.

Dorsal fin ii,7; dorsal spinelet V-shaped, dorsal-fin locking mechanism present, last ray of dorsal fin not reaching preadipose plate when adpressed. Adipose fin with single preadipose plate and moderately long spine. Caudal fin i,14,i; caudal fin forked, ventral lobe longer than dorsal lobe; dorsal and ventral procurrent caudal rays five. Pectoral fin i,6; pectoral-fin spine reaching just posterior to pelvic fin when adpressed ventral to pelvic fin. Pelvic fin i,5; pelvic-fin spine extending to posterior end of base of anal fin when adpressed. Anal fin i,4; anal-fin spine slightly shorter than first ray.

Teeth bicuspid with lateral lobe three-quarters length of medial lobe and distal tip of lateral cusp one-half width of tip of medial cusp. 39-72 left dentary teeth (mode 56). 41-73 left premaxillary teeth (mode 64).

Color.

Base color red brown, intensity of red greater in smaller specimens. Head and nape almost completely dark brown with some extremely small spots faintly visible on posterodorsal surface of head and nape, many of the spots combining to form vermiculations. Compound pterotic slightly lighter than rest of head and small spots slightly more evident. Pectoral fin dark brown with faint, large, oblong spots along leading edge. Pelvic fin as pectoral but lighter. Dorsal fin with oblong spots along spine, rays red brown, and membranes dark. Caudal fin with three to five bands that may be regular (contiguous along height of fin) or irregular (ventral and dorsal parts offset); lighter interspaces red brown, usually slightly narrower than dark bands (the largest individual examined has the light interspaces much narrower than the bands, which are very irregular). Body with four saddles, first below middle of dorsal fin, second with anterior half below posterior end of dorsal fin and posterior half behind dorsal fin, third beginning one to two plates anterior of preadipose plate to about posterior third of adipose-fin membrane, and fourth beginning just posterior to adipose fin to end of caudal peduncle; first and second saddles and usually third connected at median plate series; saddles appear to be formed of two bars each that fuse as specimens get older, and connection between bands form because the ventral sides appear to get darker with age. Ventral surface uniformly light except for the present of blotches from anterior insertion of anal fin to caudal fin, which may or may not be extensions of the saddles onto the ventral surface.

Sexual dimorphism.

It appears that some of the larger specimens (presumably male) are slightly more hispid, suggesting that nuptial males may develop hypertrophied odontodes on the lateral plates; however, no specimens have hypertrophied odontodes. The larger specimens also have the odontodes on the pectoral-fin spines moderately hypertrophied, which may also be a nuptial male characteristic.

Distribution.

Known only from the type locality in the rio Madeira drainage of Brazil (Fig. 3).

Etymology.

Ephippiata is Latin for saddled and refers to the presence of saddles in this species.

Remarks.

Many of the specimens in the type series contain a significant load of larval Neascus -type metacercariae (visible as black spots on the body and fins in Figure 2). This type of trematode burrows in the skin as larvae and the host mounts a response whereby pigment cells surround the cyst, making the cysts black (C. Sunderman and K. Hayden, pers. comm.).