Two new species of Elacatinus (Teleostei: Gobiidae) from the Mexican coast of the Gulf of Mexico

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1 Zootaxa 1425: (2007) Copyright 2007 Magnolia Press ISSN (print edition) ZOOTAXA ISSN (online edition) Two new species of Elacatinus (Teleostei: Gobiidae) from the Mexican coast of the Gulf of Mexico MICHAEL S. TAYLOR 1,3 & LAD AKINS 2 1 Dept. of Biology, Southeast Missouri State University, Cape Girardeau, Missouri 63701, USA. 2 Reef Environmental Education Foundation (REEF), P.O. Box 246, Key Largo, Florida, 33037, USA. lad@reef.org 3 Corresponding author: mtaylor@semo.edu Voice: (573) , Fax: (573) Abstract Two new species of gobies (Teleostei: Gobiidae) were recently discovered off the coast of Veracruz, Mexico in the southwestern Gulf of Mexico. Elacatinus jarocho sp. nov. can be diagnosed from other species in the genus by the disjunct yellow lateral stripe restricted to the head and caudal fin base, the yellow medial stripe on the snout, and the black ovoid to rectangular spot at the base of the caudal fin, immediately ventral to the yellow dash. This species forms shoals in the water column close to rock and coral reefs, feeding presumably on zooplankton, a trait shared by only one other species in the genus. Elacatinus redimiculus sp. nov. can be diagnosed from other species in the genus by the distinct reddish orange blotches or broken bands on the head and 13 reddish orange to dark brown stripes between the pectoral and caudal fins. Both species are currently known only from the southwestern Gulf of Mexico from reefs within the Veracruz Marine Park off the coast of Veracruz, Mexico. Key words: Gulf of Mexico, Atlantic Ocean, reef fish, new species, goby Introduction The teleost family Gobiidae comprises the largest family of marine fishes worldwide (Nelson 1994), and gobies are the numerically dominant fishes associated with Neotropical coral and rocky reefs reefs (Robertson 1998). In the Neotropics, one of the largest genera of gobies is Elacatinus Jordan with two subgenera, Tigrigobius Fowler and Elacatinus (Hoese 1971; Eschmeyer 1998). (We distinguish between the genus and subgenus Elacatinus with sensu lato [s.l.] and sensu stricto [s.s.], respectively.) The subgenus Tigrigobius has five nominal species in the eastern Pacific Ocean (but see Hoese & Reader 2001 for a suggested synonymy) and seven species in the western Atlantic Ocean. In contrast, the subgenus Elacatinus has only a single species in the eastern Pacific, but 15 species are found in the western Atlantic. Together, the 22 western Atlantic species of Elacatinus (s.l.) are distributed variously from Bermuda and the coast of the southeastern United States, southward throughout the Bahamas and Caribbean Sea, to the reefs and offshore islands of Brazil (Böhlke & Robins 1968; Colin 1975; Sazima et al. 1997; Colin 2002; Guimarães et al. 2004). However, the genus is notably depauperate in the Gulf of Mexico, with only three species, E. oceanops Jordon, E. xanthiprora (Böhlke & Robins) and E. macrodon (Beebe and Tee-Van), previously reported. Recent faunal surveys performed during in the Veracruz Marine Park of Mexico, along the southwestern coast of the Gulf of Mexico, revealed two new species of Elacatinus, one from each subgenus, both of which are described here. Accepted by A. Gill: 31 Jan. 2007; published: 15 Mar

2 Material and methods Specimens were collected by SCUBA using hand nets. Counts and measurements follow Böhlke and Robins (1968). All measurements were taken with dial calipers, and meristic counts were determined with the aid of a dissecting microscope. Meristic values for other Elacatinus species were taken from the original descriptions. Institutional abbreviation follows Leviton et al. (1985). Elacatinus jarocho, sp. nov. Jarocho Goby Figures 1,2 Elacatinus jarochus (nomen nudum), Reef Environmental Education Foundation newsletter, Spring Type series: Holotype: UF , Ahogado de Guilligan, Gulf of Mexico, Veracruz, Mexico; 'N, 'W; 18 m depth; March Paratypes: UF (2 specimens), same as holotype. UF (2 specimens), La Banquilla Reef, Gulf of Mexico, Veracruz, Mexico; 'N, 'W; 16 July Diagnosis: Elacatinus jarocho is readily distinguished from other species of Elacatinus (s.s.) by the disjunct yellow lateral stripe that appears as a dash over the eye and on the caudal fin, a yellow medial stripe on the snout, and a black ovoid to rectangular spot at the base of the caudal fin, immediately ventral to the yellow dash. Description: Morphometrics of all type specimens ( mm SL) as a percent of standard length (mean): head length, (27.6); body depth at dorsal origin, (17.8); caudal peduncle depth, (11.5); eye diameter, (9.1); snout length, (4.8); upper jaw length, (10.2); pectoral fin length, (18.1); pelvic fin length, (15.1); caudal fin length, (18.0). Fin ray counts (mode): D. VII, (11); A (11); pectoral rays, (16). None of the dorsal spines are elongated. The body is unscaled and somewhat laterally compressed. The subterminal mouth is U-shaped, lacks a rostral frenum, and the tongue is truncate. The conical teeth are set in 1 2 rows. Males have a slender, conical genital papilla; females have a blunt papilla. Coloration: In life, the body is a translucent, dark bluish-grey. A disjunct, bright yellow lateral stripe occurs just above the midline. The anterior segment of the yellow stripe originates anterior to the eye and extends posteriorly to the dorsal edge of the preoperculum. The posterior segment of the yellow stripe begins at the caudal peduncle and extends into the caudal fin rays (Fig. 2). The snout is marked with a yellow medial stripe, which begins near the upper lip and widens slightly to end between the eyes. A dark, broad lateral stripe begins at the anterior tip of the head, extends along the full length of the body just below the midline, and terminates at the caudal peduncle. A black ovoid to rectangular spot on the caudal fin originates at the terminus of the dark lateral stripe and terminates in the caudal rays. The black caudal spot is adjoined to the yellow caudal dash. The ventral surface below the dark lateral stripe is pale to translucent white. All fins are translucent or transparent. No sex- or age-related coloration differences are apparent. In preservative, the medial yellow stripe on the snout is marked by melanophores, and is surrounded by a narrow zone devoid of melanophores. The rest of the snout anterior to the eyes, and the upper lip, are dusky. A thin strip of melanophores extends from behind the eye to trail off on the operculum. This strip demarcates the ventral edge of the anterior yellow segment. The anterior and posterior yellow segments, and an interconnecting zone above the body midline are devoid of melanophores; the trunk is otherwise evenly covered with scattered melanophores. The dark caudal spot is clearly visible. Medial fin elements are outlined with melanophores. 46 Zootaxa Magnolia Press TAYLOR & AKINS

3 FIGURE 1. Holotype of Elacatinus jarocho, UF Photograph by Michael S. Taylor. FIGURE 2. Live individual and a small school of Elacatinus jarocho, Veracruz, Mexico. Photographs by Lad Akins. Comparisons: The combination of the lateral stripe and completely unscaled body places E. jarocho in the subgenus Elacatinus (Böhlke and Robins 1968). Elacatinus jarocho is the only species of Elacatinus (s.s.) thus far known to have a disjunct lateral stripe. Two other species, E. chancei (Beebe and Hollister) and E. tenox (Böhlke and Robins), have yellow lateral stripes restricted to the head, but these species do not have a yellow dash on the caudal fin, and neither species has been reported from the Gulf of Mexico. A complete lateral stripe (no disruption) is found on all other species of Elacatinus (s.s.). Elacatinus oceanops, which is commonly observed on the same reefs as E. jarocho, has a solid blue lateral stripe (no yellow), no medial TWO NEW SPECIES OF ELACATINUS Zootaxa Magnolia Press 47

4 stripe on the snout, an inferior mouth, and rests on living coral and rocky substrate (Colin 1975) instead of schooling in the water column. Distribution: Elacatinus jarocho is known only from the Veracruz reef system near Veracruz, Mexico. Specimens were observed as far north as Isla De Lobos ( 'N, 'W) and as far south as Anton Lizardo (approximately 'N, 'W). Etymology: The specific name, jarocho, is applied as a noun in apposition. Jarocho is the common local name for Veracruzanos, the native people of Veracruz, Mexico. We are pleased to honor the Jarocho, who have embraced the protection and conservation of the Veracruz reef system. The proper pronunciation is hah- ROH-cho. Remarks: Elacatinus jarocho was found between 3 25 m depth on high profile coral reefs typically dominated by Montastrea cavernosa (Linneaus), M. annularis (Ellis and Solander), Colpophyllia natans (Houttuyn) and skeletal reef framework. Elacatinus jarocho joins E. atronasus (Böhlke & Robins) as the only two species in the genus to school in the water column. Small to large aggregations (12 60 individuals) of E. jarocho were normally found close to the reef near high profile corals or overhangs. Such reef structure presumably provides shelter from direct sunlight because aggregations were usually observed in darker, shaded areas rather than in direct sunlight. Individuals of E. jarocho, unlike E. atronasus, were never observed stationary on any substrate, but rather hovered continuously about 5 25 cm above the reef (Fig. 2), frequently in association with Coryphopterus hyalinus Böhlke & Robins or C. personatus (Jordan & Thompson). This species was not observed to clean other species or interact in other symbiotic relationships. Small and large individuals coexisted in the same aggregations and did not display territorial or hierarchical behaviors. Individual fish would often, though not always, move slowly toward cover when approached to less than 1 m by scuba divers. Elacatinus redimiculus, sp. nov. Cinta Goby Figures 3,4 Type series: Holotype: UF , La Banquilla Reef, Gulf of Mexico, Veracruz, Mexico; 'N, 'W; 16 July Paratypes: UF (2 specimens), same as holotype. Diagnosis: Elacatinus redimiculus can be distinguished from other species of Tigrigobius by the reddish orange blotches or broken bands on the head and the 13 reddish orange to dark brown bands between the pectoral fin and caudal fin. Description: Morphometrics of all type specimens ( mm SL) as a percent of standard length (mean): head length, (27.4); body depth at dorsal origin, (19.8); caudal peduncle depth, (11.2); eye diameter, (7.6); snout length, (6.2); upper jaw length, (10.6); pectoral fin length, (29.6); pelvic fin length, (20.2); caudal fin length, (21.8). Fin ray counts: D. VII, 11; A (mode = 9); P. 17. FIGURE 3. Holotype of Elacatinus redimiculus, UF Photograph by Michael S. Taylor. 48 Zootaxa Magnolia Press TAYLOR & AKINS

5 FIGURE 4. Live individuals of Elacatinus redimiculus illustrating rocky and coral habitat, Veracruz, Mexico. Photographs by Lad Akins. The body is elongate, laterally compressed, and naked except for usually 4 basicaudal ctenoid scales, arranged typically in a single, vertical row on each side of the peduncle. One specimen has a fifth scale in a second row on the right side, and another specimen has two scales on the left ventral half of the peduncle, and none dorsally. The tongue is bilobed. The conical teeth are arranged in a single row, but males have enlarged, recurved canines. Males also possess an elongated first dorsal spine. Males have a slender, conical genital papilla; females have a blunt papilla. Coloration: In life (Fig. 4), the body is a translucent straw color. Internally, alternating black and white dashes extend along the midline from the operculum to the caudal peduncle. The gut is marked by two large, black blotches. The posterior blotch is surrounded and separated from the anterior blotch by bright white. A duller white coloration extends anteriorly from below the anterior blotch throughout the head. Externally, the face, lips, cheeks and operculum are marked with reddish-orange blotches or broken bands. The posterior cephalic region is marked by two reddish orange bands that drape from the nape down along the sides of the head. The first occurs approximately midway between the eyes and the origin of the first dorsal fin. This band drapes across the center of the operculum and merges with a reddish orange opercular spot. The second band TWO NEW SPECIES OF ELACATINUS Zootaxa Magnolia Press 49

6 occurs just anterior to the first dorsal origin and descends the side anterior to the pectoral fin, and reaches as far as the pectoral fin insertion. Posterior to the pectoral fin, the body is marked by 13 equally spaced bands that grade from dull, orange-tan anteriorly to dark brown bands posteriorly. Anterior to the second dorsal fin, the bands are restricted to the dorsum and sides, but completely encircle the body posterior to the origin of the second dorsal fin. The bands are thin, with the intervening space approximately twice the width of a single band. In preservative, the dark bands of the body are clearly evident. The bands are somewhat thicker on the dorsal surface of the fish, but are otherwise thinner on the lateral and ventral surfaces. The space between bands is lightly covered with tiny melanophores. The head is evenly covered with scattered large melanophores. Denser concentrations of melanophores represent the orange markings found on the head. Comparisons: The combination of a banded body, and basicaudal scales on an otherwise completely unscaled body places E. redimiculus in the subgenus Tigrigobius (Böhlke and Robins 1968). Elacatinus redimiculus joins E. macrodon as the only species of Tigrigobius reported from the Gulf of Mexico. Further, these two species are most similar in color and morphology. However, the banding pattern of E. macrodon continues onto the head as distinct bands or bars, while the head of E. redimiculus is decorated with blotches and broken bands, differences that are apparent even in preserved specimens. The only other Tigrigobius that may confuse identification is E. zebrella (Robins), but the latter species has broad bands that are nearly equal in size to the intervening pale zone (Robins 1958), and is known only from the southern Caribbean Sea. Distribution: Elacatinus redimiculus is known only from the western Gulf of Mexico reef systems within the Veracruz Marine Park. Specimens were observed on reefs as far north as Isla De Lobos ( 'N, 'W) and south to Isla Verde off Veracruz ( 'N, 'W). Etymology: The specific name, redimiculus, refers to ribbons that were sometimes attached to the side of a headdress then passed over the shoulders to drape across each side of the breast, or decoratively woven or plaited into hair. We apply this name as an adjective to describe the reddish-orange bands or ribbons that drape down across the nape and anterior trunk of this goby. The common name, cinta, is Spanish for ribbon. Remarks: Elacatinus redimiculus was typically found on brightly illuminated surfaces of either living Colpophyllia natans or algae encrusted covered coral remnants in shallow waters between 3 8 m depth (Fig. 4). Most specimens observed were not inclined to move before an extremely close approach. Once disturbed, individuals would move rapidly a short distance (less than 50 cm) across the substrate, before returning to a stationary position. After repeated disturbances, individuals would retreat into the cover of small holes, crevices or the underside of eroded corals. Feeding behavior was not observed, though it would be anticipated to approximate that of other Tigrigobius species. No cleaning or reproductive behavior was noted. Acknowledgements Most special thanks and appreciation to Sra. E. Carvajal Hinojosa, Director of the Parque Nacional Sistema Arrecifal Veracruzano, for bringing the Reef Environmental Education Foundation (REEF) to the Veracruz Marine Park, as well as her support and technical advice in collecting and exporting specimens. REEF volunteers S. Shea, R. Garcia, and I. Aretxaga Mendez assisted with the initial discovery and the subsequent documentation. Thanks to the staffs of the Veracruz Aquarium and the Veracruz Marine Park for logistical support and collecting efforts. The Comision Nacional De Acuacultura Y Pesca and the Comision Nacional De Areas Naturales Protegidas provided collection and export permits (Permits , DGOPA/4872/ , and DPNSAV/211/2005). We also thank M.E. Hellberg, H. Hollocher, D. Lodge, and N. Crochet for technical support, R. Robins and the Florida Museum of Natural History for curatorial assistance, and C.R. Robins for resolving a nomenclatural issue. 50 Zootaxa Magnolia Press TAYLOR & AKINS

7 Literature cited Böhlke, J.E., Robins, C.R. (1968) Western Atlantic seven-spined gobies, with descriptions of ten new species and a new genus, and comments on Pacific relatives. Proceedings of the Academy of Natural Sciences of Philadelphia, 120, Colin, P.L. (1975) Neon gobies T.F.H. Publications, Inc., Neptune City, N.J. Colin, P.L. (2002) A new species of sponge-dwelling Elacatinus (Pisces: Gobiidae) from the western Caribbean. Zootaxa, 106, 1 7. Eschmeyer, W.N. (1998) Catalog of fishes. California Academy of Sciences, San Francisco, 3 vols, 2905 pp. Guimarães, R.Z.P., Gasparini, J.L., Rocha, L.A. (2004) A new cleaner goby of the genus Elacatinus (Teleostei: Gobiidae), from Trindade Island, off Brazil. Zootaxa, 770, 1 8. Hoese, D.F. (1971) A revision of the eastern Pacific species of the gobiid fish genus Gobiosoma, with a discussion of relationships of the genus, Ph.D. Dissertation, University of California, 213 pp. Hoese, D.F., Reader, S. (2001) A preliminary review of the eastern Pacific species of Elacatinus (Perciformes : Gobiidae). Revista De Biologia Tropical, 49, Leviton, A.E., Gibbs, R.H. Jr., Heal, E, Dawson, C.E. (1985) Standards in herpetology and ichthyology. Part I. Standard symbolic codes for institutional resource collections in herpetology and ichthyology. Copeia, 1985, Nelson, J.S. (1994) Fishes of the world, 3rd ed. John Wiley & Sons, Inc., New York, 600 pp. Robertson, D.R. (1998) Do coral-reef fish faunas have a distinctive taxonomic structure? Coral Reefs, 17, Robins, C.R. (1958) Garmannia zebrella, a new gobiid fish from Trinidad, with notes on the species of the subgenus Tigrigobius Fowler. Journal of the Washington Academy of Sciences, 48, Sazima, I., Moura, R.L., Rosa, R.S. (1997) Elacatinus figaro sp. n. (Perciformes: Gobiidae), a new cleaner goby from the coast of Brazil. Aqua, Journal of Ichthyology and Aquatic Biology, 2, TWO NEW SPECIES OF ELACATINUS Zootaxa Magnolia Press 51