Hypostomus ericius, Jonathan W. Armbruster, 2003

Jonathan W. Armbruster, 2003, The species of the Hypostomus cochliodon group (Siluriformes: Loricariidae)., Zootaxa 249, pp. 1-60 : 25-28

Hypostomus ericius new species

(Fig. 9)

Holotype: PERU. Amazonas: Río Marañon dr. 1 km upstream from Caterpiza, MUSM 17441, 1, (186.8 mm SL).

Paratypes: PERU. Amazonas: Río Marañon dr. 1 km upstream from Caterpiza, MUSM 17441, 1, (186.8) . Río Marañon dr. 200 m downstream from Caterpiza, LACM 42004-9, 1, (148.3) . Río Marañon dr. Caterpiza, LACM 41893-6, 1, (80.5) and USNM 357392, 1, (93.6) . Quebrada Pastazilla, Río Santiago - Río Marañon dr. LACM 39947-7, 1, (120.9) . Loreto: Río Amazonas dr. Iquitos, AMNH 218035, 1, (85.1) . Río Itaya, Río Amazonas dr. approx. 10 km S Santa Clara, INHS 36876, 1, (80.1) . Río Itaya, Río Amazonas dr. upriver of Belém, approx. 4.5 km, Loreto, Peru, 3°47.71'S, 73°17.29'W, SIUC 29195, 1, (94.8) . Río Nanay, Río Amazonas dr. sand beach on right bank, 0.25 mi below and across river from Nina Rumi, 03°44’S, 73°20’W, ANSP 176149, 1, (104.5) .

Diagnosis: Hypostomus ericius can be separated from all other members of the H. cochliodon group by coloration: light tan-gray with well-separated spots and no stripes. In addition, H. ericius differs from H. hemicochliodon by a lack of a buccal papilla and from H. pyrineusi by the presence of strong, sharp keels on the lateral plates. Hypostomus ericius is most similar to H. oculeus from which it differs mainly in coloration and morphometrics(Fig. 10B).

Description: See Hypostomus cochliodon group description for more details. Morphometric data given in Table 1. Coloration generally tan-gray with large, widely-spaced spots. Spots present over entire body and becoming larger posteriorly. Caudal-fin membrane and rays often with black wash distally, and lighter area proximally instead of being spotted. Spots on fin spines and rays occasionally large. Spots less pronounced in juveniles, spots may be absent on abdomen. Juveniles with four faint dorsal saddles: first below anterior rays of dorsal fin, second below posterior rays of dorsal fin and slightly posterior to dorsal fin, third slightly anterior to and ventral to adipose fin, and fourth at base of caudal fin.

Dorsal fin moderately long, usually just barely reaching preadipose plate when depressed. Depressed pectoral-fin spine ventral to pelvic fin reaches beyond bases of pelvic-fin rays. Pectoral-fin spine supporting numerous stout, recurved, hypertrophied odontodes in nuptial males.

Keels sharp, very strongly developed. Orbits forming ridge distinctly raised above medial surface of head; ridges of dorsal and lateral aspect of head well-developed. Longitudinal ridge formed of raised bone and slightly larger odontodes absent on pterotic-supracleithrum beginning at postdorsal corner of orbit. Opercle usually not supporting odontodes, but sometimes up to 10 odontodes may be present on opercle (Fig. 2B). Nuptial body odontodes present (Fig. 2B). Plates in skin anterior to dorsal-fin spine usually absent or not numerous (Fig. 6A; Table 7). Cheek plates generally support several stout odontodes slightly larger than surrounding odontodes. Head appears wider and taller than in other species of Hypostomus .

Each jaw with 5-9 teeth (mode = 7), teeth large and spoon-shaped. Average angle between dentaries 53° (SD = 9°; range: 40°-69°; N=7). Lateral line plates 27-28; dorsal plates 7-9; interdorsal plates 5-7; adipose caudal plates 9-10.

Range: Currently known from the Ríos Marañon, Itaya, and Nanay of the Upper Río Amazonas drainage of Peru (Fig. 11). Hypostomus ericius is sympatric with H. hemicochliodon , H. oculeus , and H. pyrineusi .

Etymology: From the Latin, ericius, for hedgehog in reference to the many sharp odontodes on the keels.