Munroe: Western Atlantic tonguefishes of the Symphurus plagusia complex 



283 



ridge on the ocular-side lower jaw and the first dorsal 

 fin ray is usually placed posterior to the vertical 

 through the front margin of the upper eye. These two 

 species are further distinguished by the fewer scales 

 in a longitudinal series (78-89 in S. caribbeanus vs. 

 89-108 in S. melanurus), the lightly-pigmented inner 

 lining on the blind-side opercle (versus darkly-pig- 

 mented inner lining on the blind-side opercle in 5. 

 melanurus), and because the posterior dorsal and anal 

 fins and the caudal fin of S. caribbeanus have an alter- 

 nating series of pigmented blotches and unpigmented 

 areas (versus progressive darkening in posterior dor- 

 sal and anal fins without alternating series of blotches 

 and unpigmented areas in S. melanurus). Symphurus 

 caribbeanus differs from S. fasciolaris and S. melas- 

 matotheca in possessing 12 caudal fin rays (versus 10 

 and 11 in S. fasciolaris and S. melasmatotheca, respec- 

 tively) and in lacking an ocellated spot on the caudal 

 fin (present in S. fasciolaris) or pigmented peritoneum 

 (present in S. melasmatotheca). From S. leei, S. carib- 

 beanus is further distinguished in having the head 

 length considerably smaller than the body depth (head 

 length nearly equal with body depth in S. leei), in its 

 smaller eye (17-22 SL vs. 22-27 SL in S. leei), and in 

 having an unpigmented peritoneum (black in S. leei). 



Material examined 100 specimens (24.4-122 mm 

 SL). 



Counted and measured (21 specimens, 40.1-122mm SL). 

 Holotype: USNM 313487; male, 100.5 mm SL; Mayaguez Bay, Puer- 

 to Rico; 1966; Collected by J.S. Ramsey. Paratypes. Haiti: 

 FMNH 61574; (40.7); Port-au-Prince Bay; 12 Sep 1953. Nether- 

 lands Antilles: UMML 5297; (40.1); St. Martin; lm; 2 Jul 1959. 

 Puerto Rico: UPRM 740; 2(120-122); Rio Anasco; 1-2 Jul 

 1953. UPRM 1588; (98.0); Mayaguez; Mar 1962. UPRM 2926; 

 8(58.1-97.9); Guayanilla; 23 Jul 1968. ANSP 118553; (69.8); Puerto 

 Rico; 25 Jan 1971. Colombia: UMML 30087; 6(88.7-98.1); 

 8°44.5-45.6'N, 76°52.71'W; 4m; 12 Jul 1966. 



Counted (2 paratypes, 1 lot)-Colombia: USNM 313513; 2(102.8- 

 116.7); Bajo-Sabanilla, off Barranquilla; 8 Sep 1969. (60 non-type 

 specimens, 10 lots)-Puerto Rico: ANSP 115601; 7(43.3-82.5); 

 Puerto Yabucoa; 12-13 Jul 1969. UPRM 736; (95.8); Rio Anasco; 

 17 Aug 1951. UPRM 740; 8(90.0-122); Rio Anasco; 1-2 Jul 1953. 

 Cuba: MCZ 11200; (71.8); 1851. Haiti: UF 83998; 10(80.7-95.4); 

 2 km NW of Port Salut; sandy beach near eelgrass bed; 1 m; 7 Apr 

 1979. UMML 34337; 3(95.8-110). Nicaragua: UMML 34338; 

 2(79.1-94.3); 12°16'N, 83°31"W; 12m; 28 Jan 1971. Panama: 

 UMML 34339; (115); 8°49'N, 81°13'W; 18m; 21 Jul 1966. UMML 

 34340; 26(24.4-117); 9°48'N, 82°50'W; 19 m; 26 Jan 1971. USNM 

 313514; (46.2); Colon; 5 Jan 1911. 



Other non-type material examined (17 specimens, 2 lots). Cuba: 

 MCZ 25982; (108.7). Costa Rica: UMML 34341; 16(52.9-117); 

 10°40'N, 83°29'W; 29m; 27 Jan 1971. 



Comparative life histories 

 and distributions 



In addition to morphological and pigmentation differ- 

 ences among Atlantic members of the S. plagusia com- 

 plex, significant differences among members of this 

 species complex are evident in geographic ranges, 

 ecologies (primarily bathymetric occurrence), and life- 

 history traits, including adult sizes and minimal sizes 

 at sexual maturity. With the exception of S. civitatium, 

 which occurs allopatrically in coastal seas off the 

 southeastern United States and northern Mexico, these 

 species occur in the Caribbean Sea and South Atlantic 

 Ocean. Two species, S. plagusia and S. tessellatus, 

 have extensive and sympatric distributions, ranging 

 throughout insular and coastal locations from the 

 northern Caribbean Sea to as far south as Rio de 

 Janeiro, Brazil, for S. plagusia and to northern Uru- 

 guay for 5. tessellatus. The geographic ranges of both 

 S. plagusia and S. tessellatus completely overlap those 

 of S. caribbeanus and S. oculellus, species with more 

 restricted distributions. Symphurus caribbeanus occurs 

 throughout insular and coastal areas in the Caribbean, 

 with its southernmost occurrence in the western Carib- 

 bean off 'Colombia. Symphurus oculellus has the most 

 restricted distribution of the species complex, occur- 

 ring on the continental shelf along the northern coast 

 of tropical South America north of 5°S from approx- 

 imately 40°-60°W longitude. 



Overall, members of the S. plagusia complex are 

 generally shallow-water species, inhabiting nearshore 

 and coastal seas usually shallower than 80 m (Table 11). 

 Only rarely have individuals been collected deeper than 

 80 m, and none have been taken at depths greater than 

 1 10 m. In contrast, of the other eleven Atlantic species 

 possessing 12 caudal fin rays (all have a 1-3-2 ID pat- 

 tern), seven species usually inhabit much deeper waters 

 on the continental shelf and upper continental slope, 

 ranging from 35 to 700 m, with centers of abundance 

 usually between 100 and 350 m (Munroe 1987). Excep- 

 tional to this observation are four diminutive species 

 (S. arawak Robins and Randall, S. rhytisma Bohlke, 

 5. lubbocki, and S. reticulatus), which occur on shallow 

 substrates adjacent to coral reefs. 



Although three of the five Atlantic species of the S. 

 plagusia complex are known to have overlapping geo- 

 graphic ranges, the species do not occur syntopically 

 at all life-history stages, especially with respect to 

 bathymetric occurrences (Table 11). Three of the five 

 Atlantic members of the S. plagusia complex, S. pla- 

 gusia, S. tessellatus, and S. caribbeanus, occur syn- 

 topically at some stage in their life history in shallow 

 waters of the Caribbean. Juveniles of all three species 

 have been taken exclusively in beach seine and otter 



