Cathorops (Cathorops) higuchii, Marceniuk & Betancur-R, 2008

Marceniuk, Alexandre P. & Betancur-R, Ricardo, 2008, Revision of the species of the genus Cathorops (Siluriformes: Ariidae) from Mesoamerica and the Central American Caribbean, with description of three new species, Neotropical Ichthyology 6 (1), pp. 25-25 : 25-

Cathorops (Cathorops) higuchii , new species Figs. 12 and 13

Arius melanopus (non Günther); Steindachner, 1876:29 [description, Panama]; Meek & Hildebrand, 1923: 124 [description, PanamafromToroPoint, MindiReefandColón]; Miller, 1966: 795 (in part) [distribution]; Gilbert & Kelso, 1971: 23 [only name, Costa Rica].

Cathorops spixii (non Agassiz); Taylor & Menezes, 1978: 7 (in part) [description and distribution, Honduras to Panama].

Holotype. USNM 79363 , 129.0 mm SL (male), Panama, Colón Reef , 23 Mar 1912, S. E. Meek and S. F. Hildebrand.

Paratypes. USNM 286763 , 5 (1, 140.0 mm SL), Honduras, río Cruta, Caratasca lagoon, 15º26’N 83º41’W, 11 Apr 1967, G.C. Miller ; USNM 286764 , 3 , 130.0-140.0 mm SL, Honduras, Caratasca lagoon to río Cruta , 15º26’N 83º41’W, 11 Apr 1967, G. C. Miller ; USNM 286766 , 3 (2, 97.0-141.0 mm SL), Honduras, río Cruta, Caratasca lagoon, 15º21’N 83º34’W, 10 Apr 1967, G. C. Miller ; USNM 385182 , 25 (3, 125.0- 192.0 mm SL), collected with holotype ; USNM 38645 , 6 (3, 144.0- 165.0 mm SL), Panama, Colón, Aspinwall, Mar-Apr 1884 ; USNM 79346 , 3 (2, 162.0-168.0 mm SL), Panama, Colón, Mindi Reef, Mindi , canal zone, 7 Apr 1911, S. E. Meek and S. F. Hildebrand ; USNM 79415 , 1 , 134.0 mm SL, Panama, Mindi Reef, Mindi , canal zone, 7 Apr 1911, S. E. Meek and S. F. Hildebrand ; USNM 79345 , 3 (1, 140.0 mm SL), Panama, Toro Point , canal zone, 12 Apr 1911, S. E. Meek and S. F. Hildebrand ; USNM 79355 , 16 (2, 127.0-143.0 mm SL), Panama, Toro Point , canal zone, 12 Apr 1911, S. E. Meek and S. F. Hildebrand ; USNM 79365 , 1 , 138.0 mm SL, Panama, Toro Point , canal zone, 12 A. P. Marceniuk & R. Betancur-R. 33 Apr 1911, S. E. Meek and S. F. Hildebrand ; USNM 79366 , 1 , 172.0 mm SL, Panama, Toro Point , canal zone, 24 Jan 1912, S. E. Meek and S. F. Hildebrand ; USNM 79348 , 1 , 163.0 mm SL, Panama, Colón, Fox Bay , 5 Jan 1911, S. E. Meek and S. F. Hildebrand ; UF 16243 , 1 , 180.0 mm SL, Costa Rica, Limón, Tortuguero , 19 Aug 1963, C. R. Gilbert .

Diagnosis. Cathorops higuchii can be distinguished from all congeners by having 18-21 gill rakers on first arch (vs. 14-16 in C. aguadulce , 14-15 in C. fuerthii , 37-40 in C. hypophthalmus , 14- 16 in C. kailolae , and 13-16 in C. manglarensis ), slightly granulated cephalic shield ( Fig. 13 ) (vs. remarkably granulated cephalic shield in the remaining species, except in C. taylori ), and orbit diameter 11.7-18.9% of external mental barbel length (vs. 26.2- 51.8% in C. agassizii , 24.8% in C aguadulce , 19.6-27.7% in C. dasycephalus , 8.8-9.1% in C. hypophthalmus , 24.8-37.6% in C. kailolae , 23.8-47.6% in C. liropus , 26.4-42.0% in C. taylori , and 23.4-24.8% in C. steindachneri ).

Cathorops higuchii is further distinguished from C. aguadulce by having 17-21 gill rakers on second arch (vs. 13-16), shorter snout (6.1-8.0 vs. 9.3-11.6% SL), smaller orbital diameter (3.3-4.4 vs. 4.6-6.9% SL), and by lacking fleshy papillae intercalated with gill rakers on first two gill arches (vs. papillae present). Cathorops higuchii additionally differs from C. belizensis by having a longer dorsal-fin spine (18.6-22.2 vs. 15.9-17.6% SL) ( Fig. 9 ), dorsal-fin spine longer than pectoral-fin spine (vs. dorsal-fin spine as long as pectoral-fin spine), dorsal-fin spine length 35.6-43.3% of distance from tip of snout to pelvic-fin origin (vs. 29.4-33.3), and longer nuchal plate (6.3-7.5 vs. 5.6-6.4% SL). Cathorops higuchii is further distinguished from C. kailolae in possessing a wider posterior portion of supraoccipital process (2.7-3.3 vs. 1.9-2.6% SL), longer accessory tooth plates (2.6-4.7 vs. 1.3-2.5%SL), widerpremaxilla(5.7-7.7 vs. 4.3-5.4%SL), smaller orbital diameter (3.3-4.4 vs. 4.6-6.6% SL), and by lacking fleshy papillae intercalated with gill rakers on first two gill arches (vs. papillae present). Cathorops higuchii is additionally distinguished from C. mapale species group in possessing supraoccipital process length 3.1-4.5 in maxillary barbel length (vs. 2.0- 2.8) ( Fig. 14 ), and supraoccipital process length 2.1-3.1 in external mental barbel length (vs. 1.2-1.9). Cathorops higuchii also differs from C. melanopus by having a longer snout (6.1-8.0 vs. 5.3-5.5% SL), longer distance from tip of snout to posterior margin of dorsomedian groove of neurocranium (20.9-26.3 vs. 17.9- 19.1% SL), smaller orbital diameter (3.3-4.4 vs. 4.5-5.0% SL), larger distance between lateral cornu of lateral ethmoid and external limb of the supracleithrum (20.4-25.9 vs. 19.3-19.6% SL), and pelvic fin paler (vs. pelvic fin with intensive black pigmentation).

Description. ( Tables 1 and 4). Head moderately long and depressed, profile slightly convex at level of frontals and supraoccipital. Body wider rather than deeper on pectoral girdle area. Cephalic shield relatively short, slightly rugose, wide on lateral ethmoid, frontal, and supracleithrum areas, relatively broad at frontal area. Osseous bridge formed by lateral ethmoid and frontal long and slender, quite evident under skin. Dorsomedian groove of neurocranium formed by frontals and supraoccipital 34 Revision of the ariid species of the genus Cathorops relatively deep and large, its margins well marked and progressively narrower posteriorly. Supraoccipital process relatively short and broad on posterior portion, profile straight. Nuchal plate crescent-shaped, long and wide. Snout short, rounded on transverse section. Anterior and posterior nostrils moderately distant from one another. Eye lateral and small. Interorbital distance relatively long, distance between nostrils and orbit moderate. Maxillary barbel reaching proximal half of pectoral-fin spine, external mental barbel surpassing margin of gill membrane, internal mental barbel reaching margin of gill membrane.

Mouth relatively narrow, lower jaw arched. Lips thick, lower lip thicker than upper lip. Vomerine tooth plates absent. One pair of oval shaped accessory tooth plates of moderate size, distant from one another. Accessory tooth plates with large molariform teeth.Premaxilla relatively long and wide. Dentary with well pronounced posterior projection, with sharp teeth on anterior portion, molariform teeth on posterior portion, few conical teeth on intermediate area.

Soft pectoral-fin rays 10. Pectoral-fin spine long and slender; anterior margin with few granules on basal two thirds, distal third with short serrations; posterior margin straight on basal fourth, distal three quarters with short serrations. Soft dorsal-fin rays 7. Dorsal-fin spine long and slender, longer than pectoralfin spine; anterior margin with few granules on basal two thirds,

A. P. Marceniuk & R. Betancur-R. 35

distal third with short serrations: posterior margin serrated along almost its entire length. Pelvic fin high, with 6 rays.Anal fin high and relatively long at base, with 19-24 (19) rays. Upper and lower lobes of caudal fin of moderate length, upper lobe longer than lower lobe. Caudal peduncle high.

Acicular gill rakers on first arch 18-21 (19), 5 to 7 (6) on upper limb, 12 to 14 (13) on lower limb. Spike shaped gill rakers on second arch 17-21 (18), 5 to 7 (5) on upper limb, 12 to 16 (13) on lower limb. Mesial surfaces of all gill arches with developed gill rakers. Lateral and mesial surfaces of first and second gill arches without fleshy papillae intercalated with gill rakers.

Coloration in alcohol. Head medium to light brown on dorsal and lateral portions, ventrally light beige. Body with same brown coloration on dorsal portion, progressively lighter towards lateral line and light beige under lateral line. Maxillary barbel dark, mental barbels lighter, fins dark beige.

Sexual Dimorphism. Sexual dimorphism was observed in eleven females (97.0-192.0 mm SL) and ten males (125.0-163.0 mm SL), with respect to the following morphological features ( Table 4). Head relatively longer in males than in females, as evidenced by greater distances from tip of snout to pectoral-, dorsal- and anal-

36 Revision of the ariid species of the genus Cathorops fin origins, and greater distance from tip of snout to posterior margin of dorsomedian groove of neurocranium. Premaxilla broader in males than in females ( Fig. 15 ).Accessory tooth plates longer and broader in females than in males ( Fig. 15 ); plates covered by epithelial tissue, more distant from one another, and containing fewer and smaller molariform teeth in males. Posterior expansion of dentary longer and with more molariform teeth in females than in males ( Fig. 15 ). Females with longer pelvic fin and higher anal fin than males.

Distribution. The species is common along most of the Caribbean portion of CentralAmerica, from Honduras to Panama ( Fig. 11 ). Cathorops higuchii inhabits shallow coastal areas and low portions of coastal rivers

Etymology. This species is named on behalf of Dr. Horácio Higuchi, of Museu Paraense Emílio Goeldi, in recognition for his contribution to the taxonomy, systematics, and morphology of the SouthAmericanAriidae.

Figures

Fig. 12. Cathorops higuchii, holotype, USNM 79363, 129.0 mm SL (body in lateral view). Panama, Colón Reef.

Fig. 13. Cathorops higuchii, holotype, USNM 79363, 129.0 mm SL (head in dorsal view). Panama, Colón Reef.

Fig. 9. Plot of standard length against dorsal-fin spine length, for Cathorops belizensis (holotype, filled triangle; paratypes, open triangle) and C. higuchii (holotype, open circle; paratypes, filled circle).

Fig. 14. Plot of maxillary barbel length against supraoccipital process length for Cathorops higuchii (holotype, filled triangle; paratypes, open triangle) and C. mapale (holotype, open circle; non-type specimens, filled circle).

Fig. 15. Tooth plates of Cathorops higuchii. Abbreviations: atp - accessory tooth plates; Den - dentary; pe - posterior expansion; PMtp - premaxillary tooth plates.

Fig. 11. Distribution of marine and estuarine species of Cathorops in the CentralAmerican Caribbean.Cathorops belizensis (triangle) and C.higuchii(opensquare,holotype andsome paratypes;filled square,otherparatypes).Somesymbolsrepresent morethanone locality or lot ofspecimens (from www.aquarius.geomar.de).