Parodon alfonsoi, Londoño-Burbano & Román-Valencia & Taphorn, 2011

Londoño-Burbano, Alejandro, Román-Valencia, César & Taphorn, Donald C., 2011, Taxonomic review of Colombian Parodon (Characiformes: Parodontidae), with descriptions of three new species, Neotropical Ichthyology 9 (4), pp. 709-730 : 710-711

Parodon alfonsoi , new species

Fig. 1

Holotype. CIUA 1125, 103.4 mm SL, Colombia, Cesar, Municipio La Jagua de Ibiricó, lower río Magdalena drainage, río Tucuy, tributary to the río Calenturitas , 9°37’N 73°17’W, elevation 117 masl, 28 Mar 2007, U. Jaramillo.

Paratypes. CIUA 691 , 10 , 84.2-106.9 mm SL ; IUQ 2614 , 2 , 89.5- 94.2 mm SL ; IUQ 2546 , 2 c&s, 87.3-95.1 mm SL, all collected with the holotype .

Diagnosis. Parodon alfonsoi differs from its congeners in having a silvery blotch beneath the eye (vs. silvery suborbital blotch absent); a lateral stripe with conspicuous, dark, vertical projections along almost its entire length (from the opercle to the area above the anal-fin base origin) (vs. lateral stripe with inconspicuous vertical projections along its entire length or without projections). From P. suborbitalis it can be distinguished by the greater number of preanal scales (27-30 vs. 24-27); by the lower number of cusps on premaxillary teeth (11-14 vs. 15-17); and by the lower number of branched pectoral-fin rays (11-14 vs. 14-17). It differs from P. moreirai , P. pongoensis , P. caliensis , and P. apolinari by the presence of a lateral stripe with zigzag projections (vs. absence of lateral stripe with zigzag projections). From P. hilarii it is differentiated by the straight edge of the premaxillary teeth (vs. slightly rounded) and length of projections of lateral stripe (three scales vs. two scales). From P. nasus it is distinguished by elongated projections (vs. rounded projections) and in having the lateral stripe extending to the distal tip of the medial caudal rays (vs. absence of medial caudal rays with dark projection). It also differs in the number of preanal scales (27-30 vs. fewer than 27, except in P. hilarii which has up to 28); greater caudal peduncle depth (13.3-16.3% SL vs. 12.9-14% in P. atratoensis , 10.7-13.9% in P. buckleyi and 10.4-12.7% in P. pongoensis ); in having no dark spots above the lateral stripe (vs. spots present above lateral stripe except in P. bifasciatus ); and by the number of cusps in premaxillary teeth (12-14 vs. 15-19 in P. carrikeri ; 7-12 in P. bifasciatus ). It can be differentiated from P. guyanensis by the number of teeth in the premaxilla (four vs. five).

Description: Morphometric and meristic data given in Tables 1 and 2, respectively. Body cylindrical. Dorsal profile of trunk convex from posterior margin of supraoccipital process to dorsal-fin origin, angle diminishing up to adipose-fin origin, then concave to base of upper caudal-fin lobe. Ventral profile of trunk rounded to base of pelvic fins, then straight to posterior margin of anal fin and concave from that point to origin of lower caudal-fin lobe. Dorsal profile of head slightly concave

A. Londoño-Burbano, C. Román-Valencia & D. C. Taphorn 711 from snout to anterior nares, then straight until supraoccipital. Ventral profile of head straight to isthmus; branchial membranes united to each other and free from isthmus. Eyes lateral; nares at height of eye, round, with membrane of skin that separates anterior and posterior orifices. Mouth ventral, upper lip absent.

Premaxillary hemiseries of four teeth arranged in straight line, each tooth with 11-14 small cusps. Teeth fit into lower jaw. Maxilla with one or two multicuspid teeth, smaller than premaxillary teeth and deeply embedded (about half of tooth exposed) in soft tissue covering bone. Lower jaw with 1-3 outwardly curved laterally located teeth without cusps, not visible when mouth closed.

Pectoral fin short, not reaching pelvic-fin origins, located at vertical passing through posterior part of opercle, truncate, with fifth and sixth branched rays longest. Pelvic fin not reaching anal-fin origin, but reaching one scale beyond genital pore; pelvic fin inserted at vertical through middle of dorsal-fin base. Dorsal fin truncate, with first three branched rays longer and first unbranched ray completely dark, shorter than others. Dorsal-fin origin at vertical passing anterior to pelvic fin insertion but posterior to pectoral fin.Anal-fin origin at vertical passing through third scale anterior to adipose-fin origin.Anal fin not reaching origin of lower caudal-fin lobe. Caudal fin bilobed, with upper lobe little longer than lower, scales on base extending onto proximal 1/3 of fin.

Lateral line with 36-38 pored scales that reach to caudalfin base and sometimes extend onto basal third of that fin; scales in predorsal and ventral regions distributed regularly, axillary scale present, one or two normal scales in length.

Color in alcohol. Dorsal surface of snout and head gray, lighter yellow below horizontal through ventral margin of eye. Dorsum of body gray to black, darker than rest of body. Upper region of opercle with lighter blotch that contacts upper posterior part of infraorbital five. One, often rounded, conspicuous silvery spot (sometimes divided into two unequally sized spots) just below eye.

Lateral portion of body dark yellow, lighter yellow below lateral stripe that consists of 18-20 horizontally elongate spots forming zigzag stripe with dorsal and ventral projections. This stripe better defined in anterior portion to level of dorsal-fin origin; spots oblique in part from posterior margin of dorsalfin base to level of vertical through scale just anterior to analfin origin, spots vertical posterior to that point, and narrower than those on anterior portion of body. Lateral stripe extending on to middle caudal-fin rays.

Dorsal part of body separated from lateral stripe by lighter yellow row of scales that extends from snout to base of caudal fin, dorsal bands absent, color uniform. Holotype with transverse band at terminus of supraoccipital that extends to upper portion of opercle on each side of head (not observed in other specimens).

Pectoral and pelvic fin with black or brown chromatophores scattered on first rays but without forming distinct spots or bands. First unbranched dorsal-fin ray dark for all its length, black chromatophores present on all dorsalfin rays but without forming spots or bars. All caudal-fin rays with chromatophores, densest along posterior margin, and reaching their distal portion but not forming spots or bars; middle rays black to their tips. Anal fin hyaline. Adipose fin with black base and white spot in central portion. Ventral part of body lighter, without spots or chromatophores.

Sexual dimorphism. Small breeding tubercles present on head, most numerous and conspicuous on ventral surface and snout, extending to tip of supraoccipital process where tubercles are smaller, less numerous and hard to see without magnification; observed in males between 84 and 107 mm SL (all adults).

Distribution. Known from the río Tucuy, a tributary of the río Calenturitas, lower río Magdalena basin ( Fig. 2 ).

Etymology. This species is named alfonsoi , to honor Alfonso Londoño Orozco, father of the first author (AL-B), for his support and personal inspiration through the years.

Comments. The color pattern and shape of the teeth in this new species are most similar to Parodon suborbitalis , but it

Figures

Fig. 1. Parodon alfonsoi, Holotype, CIUA 1125, 103.4 mm SL. Colombia, Tucuy River, tributary of the Calenturitas River, lower Magdalena, La Jagua de Ibiricó.

Fig. 2. Distribution of Parodon species in Colombia. Parodon apolinari (star); P. buckleyi (square); P. caliensis (diamond); P. pongoensis (pentagon); P. suborbitalis (circle); P. alfonsoi (arrow up); P. magdalenensis (triangle); P. atratoensis (X). Each symbol may represent more than one locality. Open symbols represents type locality of each species.