Gobius key

Van Tassell, James L., Joyeux, Jean-Christophe, Macieira, Raphael Mariano & Tornabene, Luke, 2015, Status of Gobiosoma (Teleostei: Gobiidae) from Brazil: description of a new species, redescription of G. hemigymnum, molecular phylogeny of the genus, and key to Atlantic species, Zootaxa 4007 (4), pp. 451-480 : 474-475

Key to the Atlantic species of Gobiosoma

The following identification key is based on data compiled from many specimens examined by us and others (Böhlke & Robins 1968; Dawson 1971; Ginsburg 1933, 1939, 1942, 1944; Joyeux, Van Tassell & Macieira 2009). These records and other distribution points from Robertson & Van Tassell (2012) served as initial estimates of species ranges. These distributions were then evaluated at three IUCN Red List assessment workshops (Global Marine Species Assessment workshops in Barbados 2011, Corpus Christi 2011 and 2014), where questionable distribution points were discussed, suspected mis-identifications removed or specimens examined and re-identified if required, resulting in the ranges listed for each species below. Given the overlap in several characters, identification of a single specimen without exact locality data may not be possible.

1a Body scales and modified basicaudal scales absent........................................................... 2

1b Body scales and/or basicaudal scales present............................................................... 3

2a Posterior oculoscapular pores K and L typically present; body with distinct dark and light bars, light bars thinner; series of small single spots along midline; D 2 I,12 (I, 11–I,13); anal fin I,10 (I, 9–I,11); pectoral fin 18 (18–19); Massachusetts to Florida, (not Florida Keys), Everglade City, Florida along Gulf of Mexico coast to Veracruz, Mexico................... G. bosc

2b Posterior oculoscapular pores K and L typically absent; body pattern with indistinct bars; series of small spots along midline, typically in pairs; D 2 I,11(I, 10–I,12); anal fin I,9 (I, 8–I,10); pectoral fin 16–17 (15–18); Gulf of Mexico coast from southern Texas to Key West, Florida and along the Atlantic coast north to Miami and Cape Canaveral, Florida.......... G. robus tum

3a Only two small modified basicaudal scales present.......................................................... 4

3b Body with scales, at least on caudal peduncle; modified basicaudal scales present or absent.......................... 5

4a Anal fin I,9 (I, 8–I,10); pectoral fin 17 (15–18); Gulf of Mexico coast from Marco, Florida to Texas........... G. longipala

4b Anal fin I,10 (I, 9–I,11); pectoral fin 18–19 (17–20); Wareham River, Massachusetts to Jacksonville, Florida.... G. ginsburgi

5a Scales extending to posterior of caudal peduncle base; modified basicaudal scales present; head pores B', C(s), D(s), E, F, H' present, pores K' and L' present or absent; preopercle pores M', N, O' present..................................... 6

5b Scales not extending to posterior of caudal peduncle, ending before base of caudal fin rays; modified basicaudal scales lacking; head pores B', C(s), D(s), E, F, H' and preopercle pores M', and N' present...................................... 10

6a Head pores K' and L' absent; head and anterior of body with very distinct dark bars; first two D1 spines elongate in males, extending to middle of D2 when adpressed; sensory papillae transverse rows 1,2,3 extending from orbit to horizontal row d, row 5 continuous from orbit to below d and at anterior of row b ( Fig 13 B); Panama Canal, Atlantic coast of Panama from Bocas Del Toro, Laguna de Chiriqui to Maria Chiquita; migrant through canal into Panama Bay............ G. hildebrandi

6b Head pores K' and L' present........................................................................... 7

7a Second dorsal fin I, 10–I,11; anal fin typically I,9; pectoral fin rays 18–19; body scaled from caudal fin base to under pectoral fin base, scale pattern an anterior pointing wedge, a large naked area from pectoral fin base to second dorsal ray 3–10 and a large naked area from pectoral fin base to middle of anal fin base ( Fig. 4 A,B,C); very small, wart-like barbel in front of eye, near anterior naris.................................................................................... 8

7b Second dorsal fin I,9; anal fin I,8; pectoral fin rays 17; body heavily scaled from posterior of caudal fin to pectoral fin base, a small narrow, naked area from upper end of pectoral fin base to origin of second dorsal fin and from the lower pectoral fin base to the anus, naked area narrow, scale edge remaining close to ventral surface ( Fig. 4 D); wart-like barbel in front of eye absent; distribution southeastern Florida, Jamaica, Bahamas, Mexico (Yucatan, Gulf of Mexico), Puerto Rico, Virgin Islands and Venezuela.................................................................................... G. grosvenori

8a Anterior and posterior nostrils tubes nares tubular, with posterior naris 1/3 or less the height of anterior naris; scale pattern as in Fig. 4 A or 4C......................................................................................... 9

8b Anterior naris an elongate narrow tube, posterior naris only a raised rim; scale pattern as in Fig. 4 B; distribution found in Brazil from Anchieta, Espírito Santo to Iparana, Ceará..................................................... G. alfiei

9a Scales on body in wedge shape, scale forward of anterior of wedge in a straight thin line of scales to base of pectoral fin ( Fig. 4 A); scales in lateral series typically 31; anterior and posterior nares tubular, posterior naris 1/3 height of anterior; distribution Rio de Janeiro, Brazil to Mar del Plata, Argentina............................................... G. hemigymnum

9b Scales on body as in Fig. 4 C, scales extending to upper and lower base of pectoral fin, not reducing in size; scales in lateral series 26–29; posterior naris a short tube, less than 1/3 height of anterior naris (Colon area of Panama)......... G. spilotum

10a Adult males dark brown to almost black and first dorsal fin with 1St spine elongate; adults greater than 3 cm SL; papillae well defined, with row 2 extending below the level of d by more than 4 papillae ( Fig. 13 A); distribution Costa Rica, Panama and Venezuela...................................................................................... G. spes

10b Adult males mottled, similar to females; first dorsal fin with 1St spine not elongate; adult size less than 3 cm SL; papillae row 2 not extending below row d or if so by only 1-4 papillae...................................................... 11

11a Pectoral rays typically 17; anal fin typically I,9; posterior rows of scales 7–14; papillae row 2 not extending below row d; distribution Lake Maracaibo and vicinity, Venezuela..................................................... G. schultzi

11b Pectoral rays typically 16; anal fin typically I,8; posterior rows of scales 3–11; papillae row 2 extending below row d by 1-4 papillae; distribution Quintana Roo, Mexico south to Honduras....................................... G. yucatanum

Figures

FIGURE 4. Scale patterns of A) Gobiosoma hemigymnum, B) G. alfiei, C) G. spilotum, D) G. grosvenori. Shaded areas in A-D indicate distribution of scales on body. E) Distribution of basicaudal scales, including modified basicaudal scales on dorsal and ventral caudal peduncle.

FIGURE 13. Lateral view of sensory papillae patterns for (A) Gobiosoma spes, (B) G. hildebrandi, (C) G. yucatanum and (D) G. schultzi.