Arius cookei, a new species of ariid catfish from the tropical American Pacific

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1 aqua, Journal of Ichthyology and Aquatic Biology Arius cookei, a new species of ariid catfish from the tropical American Pacific Arturo Acero P. 1 and Ricardo Betancur-R. 2 1) Universidad Nacional de Colombia (Instituto de Ciencias Naturales), A.A (INVEMAR), Santa Marta, Colombia. aacero@invemar.org.co. 2) Universidad Nacional de Colombia/INVEMAR, A.A. 1016, Santa Marta, Colombia. pbiomar@invemar.org.co. Accepted: Keywords Arius cookei, Ariidae, sea catfishes, tropical eastern Pacific Palabras clave Arius cookei, Ariidae, bagres marinos, Pacífico oriental tropical Abstract A new species of sea catfish (family Ariidae) from the tropical eastern Pacific, Arius cookei n. sp., is described. It can be easily separated from other western American ariid species by its elongated supraoccipital process, which is 1.5 to 1.7 times longer than the width of its base (in specimens over 343 mm SL). The species is known from fresh and brackish waters from Costa Rica to Colombia. Resumen Se describe a Arius cookei n. sp., una nueva especie de bagre marino (familia Ariidae) del Pacífico oriental tropical. Esta especie se distingue fácilmente de cualquier otro árido de América occidental, por su proceso supraoccipital alargado, cuya longitud cabe de 1.5 a 1.7 veces en la anchura de su base (en especimenes mayores a 343 mm de longitud estándar). Es conocida entre Costa Rica y Colombia, en donde habita en aguas dulces y salobres. Zusammenfassung Eine neue Meereswelsart (Familie Ariidae), Arius cookei n. sp., wird aus dem tropischen Ost-Pazifik beschrieben. Sie ist leicht von anderen westlichen, amerikanischen Kreuzwelsarten an ihrem verlängerten supraoccipitalen Fortsatz zu unterscheiden, der (in Exemplaren größer als 343 mm SL) 1.5 bis 1.7 mal länger als seine Basenbreite ist. Diese Art kommt in Süß- sowie in Brackwasser von Costa Rica bis Kolumbien vor. Résumé Une nouvelle espèce de mâchoiron marin (famille Ariidae) du Pacifique tropical, Arius cookei n. sp., est décrite. Elle se distingue aisément des autres ariidés américains de l ouest par son excroissance supraoccipitale allongée, qui est 1,5 à 1,7 fois plus longue que la largeur de sa base (chez les specimens de plus de 343 mm LS). L espèce est signalée en eaux douces et saumâtres du Costa Rica à la Colombie. Sommario Viene descritta una nuova specie di pesci gatto marini (famiglia Ariidae) proveniente dal Pacifico orientale tropicale, Arius cookei n. sp. Questa specie può essere facilmente distinta dalle altre della famiglia presenti lungo la costa occidentale americana per il processo sopraoccipitale più allungato, la cui lunghezza è pari a volte l ampiezza della sua base (in esemplari oltre i 343 mm SL). La nuova specie è diffusa nelle acque dolci e salmastre comprese tra il Costa Rica e la Colombia. Introduction The catfish family Ariidae includes approximately 130 species in the world s tropical and sub-tropical seas and fresh waters (Jayaram and Dhanze, 1986). The systematic and taxonomic status of neo-tropical ariids is chaotic, since some genera lack adequate definitions and many species are undescribed. Recent counts of eastern Pacific species have ranged from 18 to 20, including one or two undescribed (Cooke, 1993; Allen and Robertson, 1994; Bussing and López, 1994; Kailola and Bussing, 1995). Kailola and Bussing (1995) presented 10 species as Arius, arguing that this genus was ad hoc, comprising many species but probably forming a non-monophyletic assemblage. We consider that five of the eastern Pacific species may be provisionally included in Arius because they have similar dentition, lapillus otoliths, and general morphology. However, in order to test their systematic status, they should be compared to the type species of the genus A. arius. Those five species are the sculptured sea catfish (also known as the bronze or Kessler s sea catfish, A. kessleri), the 133 aqua vol. 5 no

Arius cookei, a new species of ariid catfish from the tropical American Pacific chomba sea catfish (also known as the thicklip or thick-lipped sea catfish, A. osculus), the flathead sea catfish (A.

2 Arius cookei, a new species of ariid catfish from the tropical American Pacific chomba sea catfish (also known as the thicklip or thick-lipped sea catfish, A. osculus), the flathead sea catfish (A. planiceps), and two species lacking descriptions. The present paper includes a formal scientific description of one these, which is most similar to A. kessleri. Methods and materials Counts and measurements were made following Allen and Fischer (1978); all measurements were taken as the shortest line between two points. The width of the supra-occipital process was measured at the base of the process where it originates from the skull; its length was measured from the midpoint of the base to its distal end. Head depth was measured at the anterior end of the supra-occipital keel. HL is head length, SL is standard length, TL is total length. Designated types collected off the Pacific coast of Panama and Costa Rica are deposited in the fish collections of the Museo Colombiano de Historia Natural Marina, Instituto de Investigaciones Marinas y Costeras (INVEMAR-PEC), Santa Marta, Colombia, Museo de Historia Natural of the Instituto de Ciencias Naturales, Universidad Nacional de Colombia (ICN- MHN), Bogotá, Colombia, and Universidad de Costa Rica (UCR), San José, Costa Rica. The following specimens deposited in the fish collections of the Smithsonian Institution, National Museum of Natural History (USNM), Washington DC, USA, and of INVEMAR-PEC were also examined: USNM (holotype of Arius insculptus Jordan and Gilbert), USNM (paratype of Arius insculptus Jordan and Gilbert), USNM (paratype of Arius elatturus Jordan and Gilbert ), INVEMAR-PEC 3762 (Arius kessleri Steindachner, three specimens). Arius cookei n. sp. False sculptured sea catfish, cominata jetona (Spanish). Figs. 1-2 Arius kessleri (non Steindachner, 1876); Jordan and Gilbert, 1883: Netuma kessleri (non Steindachner, 1876); Meek and Hildebrand, 1923: 119.?Netuma oscula (non Jordan and Gilbert, 1883); Meek and Hildebrand, 1923: 120. Arius sp. B; Rubio and Gutiérrez, 1992: 53, Fig. 15; Bussing and López, 1994: 62; Cooke, 1996: Fig. 1 and 5; Cooke and Ranere, 1999: Tables I, III, IV, IX. Arius sp. A; Cooke, 1993: 40, Fig. 5; Cooke and Tapia, 1994: , Table I. Arius sp. B; Kailola and Bussing, 1995: 876 Holotype: INVEMAR-PEC 3752, male, 428 mm SL. Collected by S. Corro, hook and line, 29 April 1999, 7 km from the mouth of Río Santa María, París, Herrera, Panama (8 9 N, W). Paratypes: INVEMAR-PEC 3753 (female, 419 mm SL) and ICN-MHN 5721 (male, 343 mm SL), same data as the holotype. UCR 314-3, 173 mm SL, 9-18 m, Punta Guanacaste, Golfo de Nicoya, Costa Rica; UCR , 378 mm SL, Puntarenas, Golfo de Nicoya, Costa Rica (10 00 N, W). Diagnosis An eastern Pacific species of Arius characterized by the following combination of features: head length in SL; snout overhanging the mouth, which is clearly inferior, width of mouth in HL; eye diameter in HL in specimens over 343 mm SL; width of supra-occipital process 1.6 in its length in Fig. 1. Lateral view of a male paratype (ICN-MHN 5721, 415 mm TL) of Arius cookei n. sp., from the Pacific coast of Panama. aqua vol. 5 no

Arturo Acero P and Ricardo Betancur-R Description Body relatively robust; depth 5.6-5.9 in SL; width 4.4-5.3 in SL. Head relatively wide and flattened; width 4.4-4.5 in SL and 1.3-1.4 in HL; depth 5.

3 Arturo Acero P and Ricardo Betancur-R Description Body relatively robust; depth in SL; width in SL. Head relatively wide and flattened; width in SL and in HL; depth in SL and in HL. Snout overhangs, extending well forward of mouth, length in HL. Mouth broad; lips thick and fleshy, upper lip width in HL; mandibular symphysis pointed. Three pairs of barbels (one maxillary and two mental), the maxillary pair short and narrow, length in SL, reaching base of pectoral fin spines or falling short of them. Distance between anterior nostrils in HL. Distance between posterior nostrils in HL. Interorbital distance in HL. Eye small, in distance between anterior nostrils and in interorbital distance. Post-orbital length in HL. Exposed head shield clearly visible, very rugose, extending anteriorly but not quite reaching the eyes; a broad frontal depression present, but no groove. Supraoccipital process longer than wide, narrow and keeled; width in HL; length in HL. Pre-dorsal plate narrow and crescent-shaped. Mandibular band of teeth partially exposed when mouth closed; teeth pointed, fine, and strong. Palatine teeth in four patches, the inner pair smallest and separated medially. Gill rakers on first arch ; gill rakers on second arch ; no rakers on posterior surface of first two arches. Pre-dorsal fin length in SL. Dorsal fin elements I,7; dorsal fin base in SL; dorsal fin spine height in SL. Distance between dorsal fin and adipose fin in SL. Base of adipose fin in SL, as long as, or somewhat longer than base of dorsal fin; height of adipose in SL. Pectoral fin elements I,10-11; pectoral-fin base in SL; pectoral fin spine length in SL. Anal fin rays 17-21; anal fin base in SL. Caudal peduncle depth in SL. Colour in alcohol. Brown to blackish on back, whitish below. Size. The largest specimen in the Smithsonian Tropical Research Institute (STRI), Panama, reference collection is 4763 g, 640 mm SL, 790 mm TL (R. Cooke pers.comm., 2002). Fig. 2. Dorsal view of the head of a male paratype (ICN- MHN 5721, 98 mm HL) of Arius cookei, from the Pacific coast of Panama. specimens over 343 mm SL; teeth on palate villiform, forming a U-shaped pattern of four closely adjoined patches, the lateral pair largest and sub-triangular; dorsal fin spine height in HL; inner margin of pectoral fin spine with strong and curved serrations. Meristic and morphometric data of the type series appear in Table I. Habitat and distribution The species inhabits fresh and brackish waters on the Pacific side of Colombia (Rubio and Gutiérrez, 1992), Panama and Costa Rica. One of the type specimens was captured between 9 and 18 m at Golfo de Nicoya, Costa Rica. Remarks Although this species had not been formally described, it is well known to scientists working on the fish fauna of the tropical eastern Pacific. Cooke (1993), in his paper on pre-columbian fishing practices in Panama, showed an illustration of the neurocranium of the false sculptured sea catfish. In their description of Kessler s catfish, Allen and Robertson (1994) commented on the existence of a similar undescribed species, which could be distinguished from it by the shape of the supra-occipital process. Bussing and López (1994), presented a sketch of the head of this species and a short description. Kailola and Bussing (1995) also gave a description and included it in their key to ariids of the eastern Pacific. In his paper Cooke (1966, Fig. 5f) included a picture of the lapillus otolith of the species, as well as commenting on the taxonomic status of this and other related eastern Pacific sea catfishes. Finally, using radiocarbon techniques, Cooke and Ranere (1999) reported bones of the species in archaeological sites at Parita Bay, Panama, dating back at least 6000 years. Table II compares meristic and morphometric data of the type series of the false sculptured sea catfish with Colombian specimens of the sculptured or Kessler s sea catfish, because the two species have been 135 aqua vol. 5 no

4 Arius cookei, a new species of ariid catfish from the tropical American Pacific Table I. Meristic and morphometric data on the holotype and paratypes of Arius cookei n. sp. For the paratype counts, figures between brackets indicate the number of specimens with each count. Holotype measurements are given in millimetres with the ratios on the standard length appearing between brackets. Paratype measurements are given as a range; total length and standard length are expressed in millimetres, the additional measurements are ratios on the standard length. Holotype Paratypes Dorsal fin elements I, 7 I, 7 Pectoral fin elements I, 11 I, 10(2)-11(2) Pelvic fin elements 6 6 Anal fin elements 19 17(1), 20(2), 21(1) Upper and lower gill rakers on 1st arch (3)-5(1)+8(1), 9(1), 10(2) Total gill rakers on 1st arch 15 12(1), 13(1), 14(1), 15(1) Upper and lower gill rakers on 2nd arch (1)-5(1)+10(1)-11(1) Total gill rakers on 2nd arch 13 14(1), 16(1) Total length Standard length Body depth 72.8 ( 5.9) 5.6 Body width 80.9 ( 5.3) Head length ( 3.1) Head width 94.9 ( 4.5) Head depth 68.4 ( 6.3) Snout length 39.0 (11.0) Mouth width 72.6 ( 5.9) Upper lip width 7.3 (58.6) Maxillary barbels 89.7 ( 4.8) External mental barbels 68.5 ( 6.2) Internal mental barbels 37.0 (11.6) Anterior internarial distance 44.6 ( 9.6) Posterior internarial distance 37.8 (11.3) Interorbital distance 54.2 ( 7.9) Eye diameter 11.6 (36.9) Post-orbital length 86.9 ( 4.9) 5.4 Width of supra-occipital process 22.3 (19.2) Length of supra-occipital process 36.5 (11.7) Pre-dorsal fin length 177 ( 2.4) Dorsal fin base 42.9 (10.0) Dorsal fin spine height 64.2 ( 6.7) Distance between dorsal and adipose fins ( 3.7) Pre-adipose fin length 326 ( 1.3) Adipose fin base 41.7 (10.3) Adipose fin heigth 48.4 ( 8.8) Pre-pectoral fin length 110 ( 3.9) Pectoral fin base 24.4 (17.5) Pectoral fin spine length 66.6 ( 6.4) Pre-pelvic fin length 243 ( 1.8) Pelvic fin base 16.5 (25.9) Pelvic fin length 60.2 ( 7.1) Pre-anal fin length 319 ( 1.3) Anal fin base 55 ( 7.8) Anal fin height 64.9 ( 6.6) Caudal peduncle depth 23.2 (18.4) sometimes confused in the literature. Since there are two additional available names for sea catfishes of the species group that includes this new species, we examined the types of both species. Description of Arius insculptus Jordan and Gilbert (1883) was based on two specimens and mm SL from Panama. The ratios between the length and the width of the base of their supra-occipital processes were 0.87 and 0.93, respectively. Description of Arius elatturus Jordan and Gilbert (1883) was also based on two specimens from Panama; however, the holotype seems to have been lost for more than a decade (Eschmeyer, 1998). The remaining specimen is mm SL; the ratio of the length and the width of its supra-occipital process is Since in those three type specimens the supra-occipital process is wider than it is long, they are not the same as A. cookei. The status of A. insculptus and A. elatturus remains aqua vol. 5 no

5 Arturo Acero P and Ricardo Betancur-R Table II. Meristic and morphometric data of the type series of Arius cookei n. sp. (five specimens) and A. kessleri (three specimens). Counts and measurements are given as a range; total length and standard length are expressed in millimetres, the additional measurements are percentages of the standard length. A. cookei A. kessleri Dorsal fin elements I, 7 I, 7 Pectoral fin elements I, I, Pelvic fin elements 6 6 Anal fin elements Upper and lower gill rakers on 1st arch Upper and lower gill rakers on 2nd arch Total length Standard length Body depth Body width Head length Head width Head depth Snout length Mouth width Upper lip width Maxillary barbels External mental barbels Internal mental barbels Anterior internarial distance Posterior internarial distance Interorbital distance Eye diameter Post-orbital length Width of supra-occipital process Length of supra-occipital process Pre-dorsal fin length Dorsal fin base Distance between dorsal and adipose fins Pre-adipose fin length Adipose fin base Pre-pectoral fin length Pectoral fin base Pre-pelvic fin length Pelvic fin base Pelvic fin length Pre-anal fin length Anal fin base Anal fin height Caudal peduncle depth unclear, and they should be treated as probable junior synonyms of A. kessleri as proposed by Allen and Robertson (1994) and Kailola and Bussing (1995). Some differences between our material and the descriptions of the false sculptured sea catfish included in Meek and Hildebrand (1923) (as Netuma kessleri) and Kailola and Bussing (1995) (as Arius sp. B) are worth commenting on. It seems that relative eye size varies with body size, because our smallest specimen (173 mm SL) has the largest eyes (7 times in HL) and in the four other individuals ( mm SL) the eye is relatively small ( in HL). Meek and Hildebrand (1923), who examined material between 195 and 470 mm TL, gave the eye size as varying between in HL. Both previous descriptions mentioned that large individuals possess parasphenoidal teeth-patches; we have not seen those patches, but we assume that they might be present in large females. Former authors said that the inner teeth patches on the palatine may be united medially; however, our specimens have well-separated patches. Kailola and Bussing (1995) gave a gill raker count of three on the upper limb of the first arch; all our specimens have higher figures (4-5). On the other hand, it seems that the elongation of the supraoccipital process in this species is allometric, because our smallest specimen has the shortest process (13.6 in SL) compared with others ( in SL). Also, 137 aqua vol. 5 no

6 Arius cookei, a new species of ariid catfish from the tropical American Pacific the ratio between length and width of the supra-occipital process is 1.3 in the smallest paratype and 1.6 in the rest of the type series. Meek and Hildebrand (1923) indicated that the ratio is 1.7; Kailola and Bussing (1995) recorded the ratio as varying between 1.5 and 1.7. In our specimens HL varied between 3.1 and 3.5 in SL; Meek and Hildebrand (1923) gave a wider range for that relation, between 3.1 and 3.9. Our specimens have a dorsal fin spine length in HL; however Meek and Hildebrand (1923) specimens had a longer spine, varying between 1.5 and 1.9. Both Meek and Hildebrand (1923) and Kailola and Bussing (1995) reported wide geographic distribution for the species, from Mexico to Ecuador, and that it is largely restricted to marine waters. However, its presence north of Costa Rica and south of Colombia needs to be confirmed. Cooke and Tapia (1994) pointed out that the false sculptured sea catfish is commonly found in the mouths and fresh water sections of major Panamanian rivers, up to at least 20 km from the sea. The previous confusion between A. cookei and A. kessleri, which goes back at least to Meek and Hildebrand (1923), has obscured the true geographic range and habitat of A. cookei. Etymology We name the species for Dr. Richard Cooke (STRI) for his contribution to the knowledge of eastern Pacific ariids. Acknowledgements Dr R. Cooke provided the specimens of the type series to us; he and Dr R. Robertson (STRI) reviewed the manuscript, contributed important information, hosted one of us (AAP), and collaborated in many other ways. Dr W. Bussing (UCR) assisted with the manuscript and examined the UCR specimens. L. M. Mejía (INVEMAR/UNC) examined the type material deposited in the USNM. COLCIENCIAS and the Universidad Nacional de Colombia funded this study through proposal References Allen, G. R. & D. R. Robertson Fishes of the tropical eastern Pacific. Smithsonian Tropical Research Institute Ed. University of Hawaii Press, Honolulu, 332 pp. Allen, G. R. & W. Fischer Bony fishes. In: FAO species identification sheets for fishery purposes. Western Central Atlantic (Fishing Area 31). (Ed. W. Fischer). Vol. I, FAO, Rome. Bussing, W. A. & M. I. L, W. A Demersal and pelagic inshore fishes of the Pacific coast of lower Central America: an illustrated guide. Special Publication of the Revista de Biología Tropical, 164 pp. Cooke, R The past and present distribution of sea catfishes (Ariidae) in a small estuarine embayment in Panama: relevance to pre-columbian fishing practices. Arqueología Contemporánea 4: Cooke, R Aportes preliminares de la arqueozoología y etnología a investigaciones sobre la taxonomía, ecología y zoogeografía de las especies de la familia Ariidae en el Pacífico Oriental tropical. Cespedesia 21: Cooke, R. & G. Tapia R Marine and freshwater fish amphidromy in a small tropical river on the Pacific coast of Panama: a preliminary evaluation based on gill-net and hook-and-line captures. Annales du Musée Royale de l Afrique Centrale, Sciences Zoologiques (274): Cooke, R. & A. J. Ranere Pre-columbian fishing on the Pacific coast of Panama. In: Pacific Latin America in Prehistory: the Evolution of Archaic and Formative Cultures. (Ed. M. Blake): Washington State University Press, Pullman. Eschmeyer, W. N Catalog of fishes. Vol. I. California Academy of Sciences, San Francisco, 958 pp. Jayaram, K. C. & J. R. Dhanze Evolution and biogeography of the Indian genera of the family Ariidae. Proceedings of the Indian Academy of Sciences (Animal Sciences) 95 (2): Jordan, D. S. & C. H. Gilbert A review of the siluroid fishes found on the Pacific coast of tropical America, with descriptions of three new species. Bulletin of the United States Fish Commission 2: Kailola, P. J. & W. A. Bussing Ariidae. In: Guía FAO para Identificación de Especies para los Fines de la Pesca. Pacífico Centro-Oriental. Vol II, Part 1 (Eds. W. Fischer, F. Krupp, W. Schneider, C. Sommers, K. E. Carpenter and V. H. Niem): FAO, Rome 3: Meek, S. E. & S. F. Hildebrand The marine fishes of Panama. Part. I. Field Museum of Natural History, Zoological Series 15 (215): Rubio, R. & A. M. Gutiérrez Nuevos registros de peces pertenecientes a la familia Ariidae (Pisces: Siluriformes) en la costa pacífica colombiana. Revista de Ciencias 6: aqua vol. 5 no

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aqua Journal of Ichthyology and Aquatic Biology Vol. 5 (4), July 2002 Aquapress ISSN 0945-9871 aqua - International Journal of Ichthyology Managing Editor: Heiko Bleher Via G. Falcone 11, 27010 Miradolo