Herichthys pratinus, Maza-Benignos, Mauricio De La & Lozano-Vilano, Ma. De Lourdes, 2013

Maza-Benignos, Mauricio De La & Lozano-Vilano, Ma. De Lourdes, 2013, Description of three new species of the genus Herichthys (Perciformes: Cichlidae) from eastern Mexico, with redescription of H. labridens, H. steindachneri, and H. pantostictus, Zootaxa 3734 (2), pp. 101-129 : 109-111

Herichthys pratinus n. sp.

Figures 6 , 7 , and 15; Tables 4 and 5

Holotype. UANL 19212 (120.6 mm de SL, adult male), Río Micos, San Luis Potosí, México. Lat. 22.11626667, Long. −99.16976667, 223 masl, M. De la Maza-Benignos, June 27, 2006.

Paratypes. Twenty-six specimens, 67.6–120.6 mm SL. San Luis Potosí: UANL 17503 (26: 67.6–120.6 mm SL), other data same as for holotype.

Diagnosis. This species is distinguished by predorsal contour steep and flat, and a concavity before eye; prominent forehead that develops a nuchal hump in adult males. Dorsal and ventral contours are conic, straight to moderately convex, making intersection with caudal peduncle conspicuous. Also distinguished using the following combination characters: distance from anal fin origin to hypural base (mean 36%, SD 1%). Mouth slightly angled downward. Lower pharyngeal plate moderately stout and broad; 2 rows of 8–9 stout molars increasing in size posteriorly and molarization flank the midline, 4 most posterior molars flattened. Spiny dorsal fin rays V.

Description. Description is based on sexually mature specimens> 67.6 mm SL. Morphometric and meristic data are summarized in Tables 4 and 5. Body elongate, depth, 39%–43% (mean 41%, SD 1%); head long, 34%– 41% (mean 38%, SD 1%); caudal peduncle length 14%–17% (mean 16%, SD 1%) [all in SL]. Predorsal contour steep but not acute; concave before the eye. Concavity accentuates as the fish grows. Forehead prominent, forming a nuchal hump in adult males. Dorsal and ventral contour conic, straight to moderately convex; dorsal contour slopes backward producing a 10° angle with the horizontal, which abruptly changes to 80° close to the intersection with the caudal peduncle. Ventral profile straight or slightly convex, forming a 5° angle with the horizontal, which abruptly changes to 45° between the frontal area of the anal fin base and the intersection with the caudal peduncle, giving the body a conic appearance, and the intersection with the caudal peduncle is conspicuous. Mouth slightly angled downward, snout short, 35%–44% (mean 40%, SD 2%) of HL. Dorsal fin XV–XVI (mode XVI, freq 80%), 10–11 (mode 10, freq 50%), set forward with respect to a vertical with posterior border of opercle (intersects between 1st and 3rd rays), depressed fin short, point rarely expands beyond the anterior 3rd of the caudal fin. Anal fin V (mode V, freq 100%), 8–9 (mode 8, freq 60%). Pectoral fins asymmetric and rounded. Caudal fin rounded. Scales in longitudinal series, 29–33 (mode 31, freq 40%). Anterior teeth regularly set, well-spaced, conic, unicuspid, rounded, strongly recurved, and acutely pointed, with erect implantation; a pair of well-developed recurved fangs, reddish in color, in the upper jaw, and a 2nd less-developed pair in the lower jaw; 22 teeth in outer series of premaxillae; 6–8 frontal teeth regularly set, acutely pointed, caniniform, and with moderately stout necks; lateral and posterior teeth are small, non-caniniform, and irregularly set. Three rows in the lower jaw and 3 rows in the upper jaw; posterior rows diminutive, irregularly set teeth and hardly visible. The lower pharyngeal plate moderately stout and broad, indentation is spaced. Two rows of 8–9 lightly pigmented stout molars, increasing posteriorly in size and molarization flank midline; 4 most posterior molars flattened; all teeth, except lines along outer margins and near horns, enlarged or molariform. Eighteen conic-flattened and enlarged teeth along the posterior margin. Stomach with robust-walled, moderately saccular, and with longitudinal folds; anterodorsal section stomach adhered an elongated, elastic, and smooth caecum (length similar to that of the stomach). Gutcoiling pattern forms a double medial loop; the secondary loop projecting away and passing under the gut. Peritoneum uniformly dark.

Coloration in preservative. Dorsum and head reddish, slightly darker than remainder of body. Ventral area tan or whitish. Dark and tiny speckles present at regular intervals along dorsum of head and snout to the anterior edge of the orbit and lachrymal. Some dark dots may be present in lower half of the body around or anterior to anal fin; density of dots very low. Patterns on flanks vary. Some show six dark blotches along flanks below the lateral line, including a conspicuous marking at the base of the caudal fin. Fins tan and opaque. Dorsal fin with central dark spot beginning at the 5th spine, and extending along the dorsal contour and onto the end of the soft portion of the fin.

Live colors. Basic color olive green with tiny speckles on snout and head, particularly along the dorsal region. Speckles do not extend beyond the line between the edge of lips and the ventral edge of the orbit. All have a red marking in the axil behind the pectoral fin. Dorsal, caudal, and anal fin tips are brick red that extends onto the margin of the soft section. Random dark blotches, dots, or patterns circumscribed 6 vertical partial bands may or may not be present.

Breeding pigmentation. Breeding pigmentation shows darkening of the posterior half, starting at the vertical with the anterior end of the anal fin, and over bars 1–4, which fuse together and 3/4th of the anteroventral areas from the upper lip, passing through the ventral edge of the orbit onto the anteriormost 6th vertical bar. Pale areas include the anterodorsal 1/4th and ventral 1/3rd of the body, between the 5th and 6th bars.

Geographical distribution. Herichthys pratinus is endemic to the Rio el Salto, which runs through the Sierra La Colmena, where a series of pools and cascades called “Micos” occur. The area includes seven cascades with heights of five meters or more. Up the river is a town called El Naranjo, which is 102 km north from Ciudad Valles at the border between the States of Tamaulipas and San Luis Potosí. Two kilometers upstream from El Naranjo exists a series of pools and cascades, such as El Salto and El Meco, which are 70-m and 35-m high, respectively; both sites are inhabited by H. pratinus .

Habitat and associates. Herichthys pratinus in the lower reaches of the Rio el Salto occurs with H. cf. carpintis , Astyanax mexicanus, Xiphohorus nezahualcoyotl, and Poecilia mexicana along with other species of fishes in higher reaches.

Vernacular names. Mojarra caracolera verde, Green cichlid.

Conservation status. Currently considered as Herichthys labridens , threatened by NOM-059-ECOL-2010 and endangered by the IUCN Red List of Threatened Species.

Etymology. From the Latin word for “green,” alluding to its greenish color.

Figures

FIGURE 6. Herichthys pratinus sp. nov. collected from the Rio el Salto in the Huasteca Potosina, San Luis Potosí (~ 155 mm TL).

FIGURE 7. UANL 19212 Herichthys pratinus sp. nov. Holotype (120.6 mm SL). Mauricio De la Maza-Benignos, Figures 8 – 9.