Ancistrus martini Schultz 1944

Taphorn, Donald C., Armbruster, Jonathan W., Villa-Navarro, Francisco & Ray, C. Keith, 2013, Trans-Andean Ancistrus (Siluriformes: Loricariidae), Zootaxa 3641 (4), pp. 343-370 : 357-359

Ancistrus martini Schultz 1944

( Figs. 8 and 9 )

Images of the holotype of this species, USNM 121064, are available at the All Catfish Species Inventory website: http://acsi.acnatsci.org/base/image_list.html?mode=genus&genus= Ancistrus

Ancistrus triradiatus martini, Schultz 1944: 302 , pl. 9 (fig. C). Type locality: Río Táchira, 7 km. north of San Antonio, Catatumbo system; Venezuela. Holotype: USNM 121064. Paratypes: MCZ 37233 (1), USNM 120094 (1), 121065 (3, now 2, 1 to MCZ); Pérez & Viloria (1994).

Ancistrus martini, Schultz 1944 . Isbrücker (1980) raised subspecies to species level; Ferraris & Vari (1992) (type catalog); Burgess 1989; Isbrücker (2001); Isbrücker (2002); Fisch-Muller (2003) Ferraris (2007) (list).

Ancistrus brevifilis bodenhameri, Schultz 1944:305 , pl. 10 (fig. A). Type locality: Río San Pedro at the bridge south of Mene Grande, Motatán system; Venezuela. Holotype: USNM 121066. Paratypes: MCZ 37241 [ex USNM 121067] (3); UMMZ 141940 [ex USNM 121067] (6); USNM 121067 (132, now 123), 121068 –69 (1, 2), 121299 (1). Isbrücker (1980), relocated to species level, Pérez & Galani (1994) .

Ancistrus bodenhameri, Schultz 1944 . Ferraris & Vari (1992) list; Pérez & Viloria (1994); Isbrücker (1980); Burgess (1989); Isbrücker (2001); Isbrücker (2002); Fisch-Muller (2003); Ferraris (2007).

Diagnosis. Ancistrus martini can usually be distinguished from Ancistrus caucanus by having a snout length to head length ratio of 55.5–65.3% (vs. 45.9–55.9%). Although pigmentation is notoriously variable among individuals of most Ancistrus species examined, most specimens of Ancistrus martini can be distinguished from A. caucanus , A. tolima , and A. vericaucanus by having better defined light spots on body and fins in addition to relatively small dark spots on the fin rays and membranes that form six to nine irregular bands on the caudal fin (vs. three to five regular or irregular bands) and seven to nine spots along the pectoral-fin spine (vs. three to six spots). They also differ in the ratio of head-eye length to snout length: 53.9–72.1% in specimens greater than 60 mm SL (vs. 72.3–91.9%; Fig. 3 C). A. martini differs from A. centrolepis by having white spots on the body (vs. dark spots on body or body entirely gray), by lacking rows of enlarged odontodes on the lateral plates (vs. one to three rows of greatly enlarged odontodes) and by having the longest odontodes on the lateral plates less than half as long as the supporting plate is wide (vs. longest odontodes almost as long as the supporting plate is wide); from A. galani by having fully developed eyes and pigment (vs. eyes reduced and pigment absent or reduced); from A. tolima and A. vericaucanus ) by usually having one preadipose plate (vs. two to three, rarely one in A. vericaucanus , and three to five in A. tolima ); and from A. tolima by having the adipose fin spine at a 45° angle to the body and adipose-fin membrane present (vs. adipose-fin spine adnate and adipose-fin membrane absent).

Description. N = 48. Morphometrics given in Table 3 . Size range this study 46–111 mm SL.

Body broadest anteriorly, greatest body width at base of pectoral fins then narrowing progressively to end of caudal peduncle. Head and body somewhat depressed, greatest body depth at or just posterior to pectoral-fin bases. Caudal peduncle deep, posteriorly compressed. Dorsal profile anteriorly convex from tip of snout to dorsal-fin origin; ventral surface of head straight and flat; chest and abdomen with gently convex profile.

Head broad, interorbital width about equal to depth of body. Snout obtuse, naked margin wider in males; snout length greater than one-half head length. Eye moderate, upper orbit margin not protruding from dorsal profile of head. Oral disk ovate, wider than long. Lips covered with minute papillae, larger near mouth. Lower lip moderate in size, not reaching gill aperture, its border covered with very small papillae. Maxillary barbel short, its length less than orbit diameter. Dentary tooth row straight, about same size as premaxillary tooth row. Teeth numerous (45– 100 per jaw ramus), asymmetrically bifid, medial cusp much larger and spatulate, lateral cusp minute and pointed, usually not reaching more than half length of medial cusp, but equal in worn teeth. Hypertrophied cheek odontodes strongly evertible, eight to 18 odontodes of various lengths with tips hooked anteriorly, bases encased in thick fleshy sheaths. Head smooth, bones on back of head not carinate; supraoccipital with margins between surrounding bones and plates usually clearly visible. Lateral plates not carinate.

Ventral surface of head and abdomen naked. Nuchal plate small and curved posterolaterally. No enlarged odontodes at edge of lateral plates. Five series of lateral plates anteriorly, three series on caudal peduncle, middorsal and mid-ventral plate series end on caudal peduncle beneath adipose fin. Last plate in median series slightly smaller than penultimate plate, base of caudal fin with about four small platelets after main series, then about eight roughly triangular platelets covering bases of caudal-fin rays.

Dorsal-fin origin situated anterior to vertical through pelvic-fin insertion. Dorsal fin moderately elevated, usually reaching preadipose plate when depressed; dorsal-fin base length noticeable greater than dorsal-adipose distance. Adipose fin well developed, spine stout, elevated from body at about a 45º angle. Pectoral fins reaching past base of pelvic fins, but failing to reach the middle of these fins, the spine shorter than head. Anal fin small, its origin at vertical through base of last ray of dorsal. Pelvic fins reaching well past anal-fin origin, inserted posterior to vertical through first branched dorsal-fin ray. Caudal fin with gently convex margin.

Tiny odontodes present on body plates, largest on posterior margins of plates. All fin spines with small odontodes, more developed in pectoral-fin spine of males. All fin rays with tiny odontodes on rays.

Mid-dorsal plates 5(1), 6(2), 7(3), 8(6), 9(9), 10(8), 11(3), 12(2), 16(2), 17(3), 18(5), 19(1); median plates 21(1), 22(7), 23(23), 24(14); mid-ventral plates 14(1), 16(18), 17(12), 18(8), 19(3) 20(2); plates bordering dorsalfin base 6(13), 7(28), 8(3), 9(1); plates between dorsal and adipose fins 6(3), 7(40), 8(2); preadipose plates: 1(45). Fin-ray formulae (N=44): dorsal i,7; pectoral i,6; pelvic i,5; anal i,3(1) i,4 (43); caudal i,14,i. Caudal procurrent spines: dorsal: 4(7), 5(37), ventral: 2(2), 3(28), 4(14).

Color in alcohol. ( Fig. 8 ). Base color brown, numerous light spots present on head, barbels and body, head spots smallest anteriorly, larger posteriorly. Flanks usually brown with large, light rounded spots. Abdomen usually tan or brown with light spots which vary in size, shape and number among individuals, sometimes running together to form vermiculations. Fins brownish with alternating dark and light spots on rays. In newer material, the dorsal, caudal, pelvic and pectoral fins have dark spots on spine and fin rays that may extend onto membranes to form bands.

Distribution. Venezuela and Colombia, rivers of Lake Maracaibo Basin.

Remarks. Schultz described two new subspecies from the Lake Maracaibo Basin (1944): Ancistrus brevifilis bodenhameri and Ancistrus triradiatus martini , each of which has been subsequently considered as valid species (Fisch-Muller, 2003). However, our morphometric analysis failed to detect significant differences between them. Schultz diagnosed his subspecies based on the color pattern of the ventrum: with separate spots in A. brevifilis bodenhameri and spots sometimes running together to form vermiculations in A. triradiatus martini . We have found great individual variation in the pigmentation pattern of the ventrum of specimens from the Lake Maracaibo Basin and so that character is not useful for distinguishing them. Based on both morphometric and pigmentation pattern differences we consider the Maracaibo species as distinct from both A. triradiatus (which occurs on the southern flank of the Andes in the Orinoco River Basin) and A. brevifilis (which occurs in the Tuy River Basin of coastal Caribbean central Venezuela). We therefore consider Ancistrus brevifilis bodenhameri Schultz 1944 as a synonym of Ancistrus martini Schultz 1944 .

Figures

FIGURE 3. Diagnostic biplots for species of Ancistrus.

FIGURE 8. Ancistrus martini INHS 35367 specimen, 73.2 mm SL, Taguara Creek, Santa Ana River drainage, Lake Maracaibo Basin, 51 mm SL. Photograph by Nathan K. Lujan.

FIGURE 9. Ancistrus martini, live, collected by and photographed by Gustavo Ballen from the upper Zulia River.