Herichthys labridens (Pellegrin 1903)

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 : 103-106

Herichthys labridens (Pellegrin 1903)

Figures 2 , 3 , and 15; Tables 4 and 5

Syntypes. MNHN 1889-0019 (1), 1889-0020 (1). Collected from the Huasteca Potosina, San Luis Potosi, Mexico. Alfredo Dugès.

Lectotype. UANL 20809 (76.7 mm SL, adult male), Media Luna, San Luis Potosi, Mexico, Lat. 21.864, Long. −100.026, 1002 meters above sea level (masl) M. De la Maza-Benignos, June 29, 2006.

Other materials examined. San Luis Potosí: UANL 17509 (15 specimens: 52–79.1 mm SL), same data as Lectotype.

Diagnosis. Lower pharyngeal plate stout, much broader than long; horns short; 4 lines of pigmented, very stout, massive molars flanking midline, including 2 central rows of 5–6 teeth. Eight central–posterior massive molars occupying 1/3rd of the plate. All other teeth, except along the outer margins, flattened (enlarged) and molariform. Distinguished from all other species in the genus by a combination of the following characters: anal fin III–V (mode V, frequency (freq) 90%), 8–9 (mode 9, freq 50%); body deep within genus [mean 44%, standard deviation (SD) 1% SL]; caudal peduncle long (mean 15%, SD 1% SL); dorsal fin origin to anal fin origin short (mean 53%, SD 1% SL); snout slightly angled downward and short (mean 33%, SD 2% HL); cheeks shallow (mean 26%, SD 2% HL). Gill rakers 5–6 (mode 5, freq 70%) on lower limb of the 1st branchial arch. Breeding pigmentation retains areas with bright yellow that contrast black markings on the lower portion of the head, ventral area, and caudal peduncle.

Description. Description is based on sexually mature specimens> 52 mm SL. Morphometric and meristic data are summarized in Tables 4 and 5. Body elongated, depth, 43–45% (mean 44%, SD 1%); head long, 36–39% (mean 38%, SD 1%); caudal peduncle long, 13–16% (mean 16%, SD 1%) [all in SL]. Predorsal contour gradual and acute, curving out before the eye; forehead inconspicuous. Dorsal and ventral contours straight to moderately convex with moderate slope; mouth slightly angled downward. Snout short, 29%–36% (mean 33%, SD 2%) of HL. Dorsal fin XV–XVI (mode XVI, freq 70%), 9–12 (mode 11, freq 50%), short when depressed, point rarely expands beyond the anterior 1/3rd of the caudal fin, set forward with respect to vertical with the posterior border of the opercle (intersects between 1st and 3rd rays). Anal fin III–V (mode 5, freq 90%), 8–9 (mode 9, freq 50%). Pectoral fins asymmetric and rounded. Caudal fin rounded. Scales in longitudinal series, 29–32 (mode 30, freq 50%). Anterior teeth regularly set, well-spaced, conic, unicuspid, strongly recurved, and pointed, with erect implantation; may be worn in older specimens; a pair of well-developed recurved fangs in the upper jaw and a less developed pair in the lower jaw; 22 teeth in outer series of the premaxillae, 6–8 frontal teeth are regularly set, acutely pointed, caniniform with moderately stout necks; lateral and posterior teeth are small, noncaniniform, and irregularly set. Two rows of teeth in the upper and lower jaws; posterior rows hardly visible, diminutive, irregularly set. Lower pharyngeal plate enlarged, wide, and stout with short horns; 14–16 stout massive molars on 1/3rd of the pharyngeal plate. Four lines of pigmented molars flank midline, 8 very large in 2 central rows. All other teeth, except those along outer margins, enlarged or molariform; 19 teeth along the posterior margin are conic and enlarged.

Robust-walled stomach, moderately saccular, rugged with longitudinal folds, adhered at its anterodorsal section to a well-elongated, elastic, smooth caecum. Gut-coiling pattern forms a double medial loop; secondary loop projecting away from the observer and passing under the gut. The peritoneum is uniformly dark.

Coloration in preservative. Body brown, darker at the dorsum, and reddish on the belly and cheeks. Head brown, darker, and speckled with few very tiny reddish dots on cheeks, spots absent in some specimens. Flanks have 6–7 conspicuous vertical blotches, starting at the midflank, darkening posteriorly, and terminating with a darker round vertical marking at the base of the caudal fin. Fins are brown and opaque.

Live colors. Ground color golden to olive–green or brownish with aquamarine. Usual color golden with 5–6 aligned black blotches in the posterior part of the flanks; head aquamarine. Fins have aquamarine dots. Herichthys labridens can modify its color to completely dark while hunting. (Artigas-Azas 1996). Color of river populations is similar to that of their spring relatives but much less golden/yellow with hunting coloration absent. A red–purple mark present on the axil of the pectoral fin.

Breeding pigmentation. Breeding pigmentation includes two colors, namely bright yellow on the upper anterior body and associated fins contrasting with black markings on the upper and lower posterior body, posterior fins, and lower portion of the head (Artigas-Azas 1996).

Geographical distribution. Endemic to Laguna Media Luna, San Luis Potosí, and headwaters of the Río Verde between 1,000 and 1,100 masl.

Habitat and associates. Herichthys labridens inhabits Media Luna, a karstic warm spring, which exists because of a tectonic ridge forming a hill southwest (SW) of El Jabalí. The spring formerly emptied into Rio Viejo, which has been blocked and diverted for agricultural purposes. This species is sympatric with H. bartoni and H. sp. cf carpintis which was translocated into the Media Luna system (Artigas-Azas, 1996).

Vernacular names. Mojarra caracolera amarilla, curve-bar cichlid, yellow labridens .

Remarks. Herichthys labridens was described as Heros labridens by Pellegrin (1903) from the type locality of “Huazteca Potosina” [sic], Guanajuato. Confusion exists with respect to the precise type locality for the species (Taylor & Miller 1983) because the type material was shipped by Prof. Alfredo Dugès from Guanajuato to Pellegrin; Guanajuato is not part of the “Huasteca Potosina,” and Guanajuato falls outside the historical distribution of cichlids. Regan’s account (1906–1908) sets its distribution as Mexico, Rio Pánuco , and its tributaries and sets the eye diameter at 4–5.5 and interorbital width at 3 (both in HL); dorsal fin XV–XVI, 10–11; and anal fin V–VI, 8–9 as diagnosable traits. Therefore, his account appears to be based on a composite of species, probably H. labridens , H. pantostictus , and H. pame sp nov. The narrative of Álvarez del Villar (1970) for H. labridens sets the mouth with all conical teeth and 6–8 gill rakers in the lower limb of the 1st branchial arch as diagnostic traits. It can be inferred from this account that he probably did not examine lineages from Media Luna. Taylor & Miller (1983) described H. labridens with a moderately elongated body and a well-developed lower pharyngeal plate with molariform teeth. Sides of the head and nuchal area are spotted with fine dark dots that do not extend onto the rest of the body. The distribution is as follows: Hidalgo: Ríos Venados and Amasa, 9.7 km from Huejutla; Veracruz: Río de los Hules in Tantoyuca, Ríos Calabozo, and Tanchochín. Querétaro: Río Santa María in Concá, 27 km from Jalpan; San Luis Potosí: Río Valles in Valles, Río Axtla in Axtla, Río Matlapa in Tamazuchale, Río Ojitipa near Tancanhuitzm, Río El Salto 11 km from Nuevo Morelos, La Media Luna, Río Moctezuma, Río Tamasopo, Río Tampaón, and Río Ojo Frío; Tamaulipas: Río Guayalejo, Río Sabinas in Gómez Farías; Ojo de Jaumave; Río Tigre; and Río Mante. Hence, Taylor & Miller’s account is based on a composite of H. labridens , H. molango sp. nov., H. pame sp. nov., H. pratinus sp. nov., and H. pantostictus in both account and origin of the material examined. Hulsey et al. (2004) recovered the clade conformed with H. labridens of Media Luna and H. bartoni of Media Luna as sister to the clade with H. pantostictus of Rio Tamesí, Rio Guayalejo, and Rio Tigre; H. pame sp. nov. of Rio Tamasopo; and H. steindachneri .

Conservation status. Threatened, according to the NORMA Oficial Mexicana NOM-059-ECOL-2010 and endangered according to the IUCN Red List of Threatened Species 2009.

Figures

FIGURE 2. Herichthys labridens (Pellegrin 1903) collected from Media Luna Spring. (~ 90 mm TL)

FIGURE 3. UANL 20809 Herichthys labridens. Lectotype (76.7 mm SL). Mauricio De la Maza-Benignos, Figures 4 – 5.