Paraeupolymnia carus Young and Kritzler, 1987

Londoño-Mesa, Mario H., 2006, Revision of Paraeupolymnia, and redescription of Nicolea uspiana comb. nov. (Terebellidae: Polychaeta), Zootaxa 1117, pp. 21-35 : 24-30

Paraeupolymnia carus Young and Kritzler, 1987

Figure 1 A–K

Paraeupolymnia carus Young and Kritzler, 1987:687 –689, fig.1;— McHugh, 1995:412;— Hutchings, 1997:495;— Díaz­Díaz and Liñero­Arana, 2000:38 –39, fig. 3i – m;— Londoño­Mesa and Carrera­Parra, 2005:25 –26, figs. 7A–D.

Material examined: Type material: Paratypes: USNM 98909 (2) North Atlantic Ocean, Caribbean Sea, Belize, Twin Cays (16°50’N, 88°06’W), 9.III.1984, 2.25 m. Comparative material examined: Florida: AMNH 363B (from AMNH 363 as Loimia bermudensis ) (2) Dry Tortugas, Florida, 1909. Gulf of Mexico: UANL 5509 (2) Pajaros. Veracruz, 27.VI.2002, Pl.2 (as Lanicides taboguillae ). UANL 5854 (1) Blanca, Veracruz, 21.V.2002, Pl.3 (as Lanicides taboguillae ). UANL 5985 (1) Hornos, Veracruz, 14.VII.2002, Pl.2 (as Terebella rubra ). UANL 5495 (2) Pajaros, Veracruz, 6.V.2001, Pl.2 (as Terebella rubra ). UANL 6005 (1) Pajaros, 30.V.2003, Pl.2 (as Terebella rubra ). UANL 6032 (1) Hornos, Veracruz, 30.V.2003, Pl.3 (as Terebella rubra ). UANL 6058 (1) Pajaros, Veracruz, 30.V.2003, Pl.1 (as Terebella rubra ). UANL 6060 (7) Hornos, Veracruz, 30.V.2003, Pl.1 (as Terebella rubra ). UANL 6061 (1) Hornos, Veracruz, 30.V.2003, Pl.2 (as Terebella rubra ). UANL 6063 (8) Hornos, Veracruz, 30.V.2003, Pl.2 (as Eupolymnia nebulosa ). ECOSUR TERE 9 (2) Alacranes Reef, Perez Island, 26.VI.1988. Mexican Caribbean: ECOSUR TERE 9 (1) R/V “Edwin Link”, sta. 2777, Southern Chinchorro (18°26.02’N 87°18.82’W), 21.VIII.1990, about 237 m. TERE 9 E2 (1) Xahauyxol (18°30’15”N 87°45’32”W), 27.IX.1996, 0.25 m. TERE 9 E22 (1), TERE 9 E25 (4) Buenavista (18°30’42”N 87°45’30”W), 27.IX.1996, 1.1 m. TERE 9 E2A39 (5) Majahual (18°40’09.6”N 87°43’01.4”W), 30.V.1997, 0.1 m. TERE 9 (1) Bajo Pepito, Mujeres, VI.1997, on algae. TERE 9 R6 (1), TERE 9 R8 (1) Punta Nizuc, Cancún (21°02’11.7”N 86°46’44.2”W), 31.VIII.1997, 2 m. TERE 9 R7 (2) Punta Nizuc, Cancun (21°02’11.7”N 86°46’44.2”W), 1.IX.1997, 2 m. TERE 9 B2RB3 (1) Buenavista (18°30’42”N 87°45’30”W), 31.X.1997, 0.25 m. TERE 9 (1) Contoy Island (21°30’8.4”N 86°47’45.3”W), 10.VI.1999, 3 m, in Ircinia sp. TERE 9 (2) Lighthouse, Contoy Island (21°30’34”N 86°47’47”W), 1.III.2001. Panamanian Pacific: UMML P568 (1) Gulf of Panama (8°56’N 79°34’W), 13.V.1967; 0m. Panama Caribbean: ECOSUR TERE 9 (19) Puerto Sherman, Colon, Panama, 2.VI.2002. ECOSUR TERE 9 (1) Punta Culebra, Balboa, Panama, 30.V.2002. TERE 9 (1) Puerto Sherman, Colon, Panama, 2.VI. 2002. TERE 9 (11) Club Nautico, Colon, Panama, 3.VI.2002. Antilles: ZMA V.POL 1203 (1) Puerto Santo, near Carupano, Venezuela, 12.VI.1936; sandy debris; lower zone. ZMA V.POL 1211A (6) Tortuga SW coast, 1.VIII.1936; sandy reef with Acropora cervicornis , 3–4m depth. ZMA V.POL 1473 (1) Curaçao, Piscadera Baai, Central part, SW, Punta Chumbu, 13.XII.1963; Rhizophora , on rocky shore, many oysters, Styela and Microcosmus , 0– 1m. ZMA V.POL 1550 (1) Grenada, Hog Island, near Point Salines, 8.VIII.1967; Rhizophora , in mud, 0–0.5m. ZMA V.POL 1551A (1) Grenada, S coast, near Hog Island, 8.VII.1967; Thalassia in muddy sand near Rhizophora , 0.5– 1m. ZMA V.POL 1618 (1) Curaçao, Fuik Baai, E corner, 28.X.1967; Rhizophora , mud, 0–0.5m. ZMA V.POL 1628 (4) Curaçao, Spaanse Water, Brakke Put Ariba, 1.XI.1968; sandy, with algae, 5m. ZMA V.POL 1633 (2) Curaçao, Spaanse Water, Inner Bay, SW of Landhius Santa Barbara, 1.XI.1968; muddy, 3m. ZMA V.POL 75–60 (1) Bonaire, Arisco Pam 1A, 22.IX.1975. AMNH 1265B (from AMNH 1265 as Loimia medusa annulifilis ) (1) Milford Bay, Tobago 28.III.1918. LEB­Te0000 (3) Guacarapo, Venezuela, 22.V.1999.

Description: Best specimen from paratypes complete, 85 segments, 24 mm long; thorax 7.2 mm, and 3.0 mm wide ( Fig. 1 A). Tentacles short. Thoracic dorsal surface smooth, with transverse wrinkles, more marked on anterior region. Tentacular membrane short, with thick prominent ridges; eyespots small, dark, restricted to the mid­lateral sides of the membrane, each group with 12–15. Upper lip with free edge spoon­like, projected forwards; lower lip smooth, thin, slightly swollen. Ventral pharyngeal organ not visible. Segment one dorsally distinct, surrounding the tentacular membrane; ventrally as two wide, swollen lobes lateral to the lower lip. Fifteen ventral shields from segment 2; anterior shields rectangular but broader laterally; shorter from mid­thorax. One pair of lateral lappets belonging to segment 2 latero­ventrally, and to segment 3 latero­dorsally; oblique to body axis, in lateral view three times as long as notopodial length. Ventral lobe free (not connected to any ventral shield), and longer than dorsal lobe. Two pairs of dichotomous branchiae, on segments 2 and 3. First pair longer, three to four levels of ramification; second pair with three levels. Stalks long, thin, smooth. Nephridial papillae not visible. Notopodial glandular patches absent. Seventeen pairs of notopodia from segment 4; notopodia conical with notochaetae all of similar length, simple bilimbate capillaries ( Fig. 1 B). Neuropodia from segment 5, sessile in thorax, becoming erect, projecting backwards in abdomen; uncini in single rows from segment 5–10, in double rows from segment 11–20, in face to face position; in single rows from segment 21 until pygidium. Thoracic uncini MF:1:3–5 ( Fig. 1 C), narrow upper subrostrum, well­developed sub­rostral process, without sub­rostral appendix; concave lower sub­rostrum; anterior process and filament both absent; base curved, terminating in an angular posterior process; lower occipitium concave, and upper convex, ending by toothed capitium. Abdominal uncini MF:2–3:4–6 ( Fig. 1 D), similar to thoracic ones, but with more secondary teeth. Pygidium short, small, surrounded by about 10 anal papillae. Tube pale green to brown, short and thin, broader than the body of the worm; made of sand attached to mucous membrane.

Var ia t io n: Variation in specimens from the Mexican Caribbean includes tentacles with dark transversal bands, dark­brown body colouration, and either with or without eyespots on the tentacular membrane. The total length may vary from 8 mm to 30 mm; the thorax length and width varies from 4–8 and 0.5–1.2 mm, respectively.

Type material examined does not have visible nephridial papillae, nevertheless, almost all the additional specimens have paired papillae on segments 3–4, which are rounded and smaller, inserted at the base of the 2nd pair of branchiae, and at posterior base of the first notopodium, and papillae on segments 6–7, are rounded, sometimes elongated, at posterior base of the 3rd and 4th notopodia. Figures 1 E–K illustrate in more detail a specimen from Contoy Island (Mexican Caribbean), with papillae on segments 6 and 7, and some variation in the length of the lateral lappets, and branchiae.

Some variation in the size of the paratypes ( Fig.1 A) and the specimens from the Mexican Caribbean ( Fig. 1 E–G) are evident. Young & Kritzler (1987) did not mention the method of relaxing and fixation followed; it is assumed that they were fixed in formalin without any prior relaxation. The specimen shown in figure 1E–G and almost all from the Mexican Caribbean were relaxed using magnesium chloride, and fixed with formalin. Thus, the consistency and shape of the thorax and branchiae could vary between specimens according to the method of fixation.

Remarks: Since being described in 1987, this species has only been recorded from Belize. Nevertheless, unsorted terebellids collected by staff of the Zoological Museum of Amsterdam during an expedition in 1967 to the Antilles, contained additional material, and indicates that this species has a wider distribution than previously thought. On the other hand, this species was identified in material from Gulf of Panama, collected by the University of Miami cruises to the Caribbean and Gulf of Panama (see material examined). Some explanations emerge for this amphi­American distribution. One is that the species has been dispersed through the discharge of ballast water, although to date this has not been recorded for any other terebellid, which tend not to have a long pelagic larval stage. Another explanation is that the species already existed on both sides before the rise of the Panama Isthmus; nevertheless, P. c a r u s has not been reported at other sites on the Pacific Ocean ( Salazar­Vallejo & Londoño­Mesa, 2004), which gives more weight to the first explanation.

Some specimens collected by Díaz­Díaz and Liñero­Arana (2000) were identified as a possible new species for Venezuela, because they were based on the original description of P. c a r u s which states that ventral shields are absent. Following an examination of these specimens, and the emended description for P. carus , based on examination of type material, it is clear that the specimens from Venezuela belong to this species. Material deposited in the AMNH identified as Loimia medusa annulifilis from Tobago, and as Loimia medusa from Dry Tortugas, Florida, included some specimens of P. carus . These findings indicate that this species is widely distributed in the Grand Caribbean region, from Florida to Venezuela. Finally, most of the specimens have been collected in shallow water, between 0–5 m depth; however, one specimen was collected from 237 m depth (R/ V “Edwin Link”), and it does not exhibit any morphological variation from the type series. This is the only deep­water record, and more deep­sea material should be collected to corroborate this finding.

Type Locality: Twin Cays, Belize, Caribbean Sea.

Distribution: Grand Caribbean region: Florida, Gulf of Mexico, Mexican Caribbean, Belize, Colon ( Panama Caribbean), Venezuela, and Lesser Antilles ( Bonaire, Curaçao, Grenada, Tortuga), and Balboa (Gulf of Panama, Pacific). Occurs in shallow water (0–5 m), rarely in deep­water (237 m).

Figures

FIGURE 1. Paraeupolymnia carus Young & Kritzler, 1987. Paratype USNM 98909: A. Lateral view; B. Chaetae, segment 8; C. Uncini, segment 8; D. Uncini, segment 11. ECOSUR TERE 9 Contoy Island, 1. III. 2001: E. Lateral view; F. Ventral view; G. Dorsal view; H. Chaetae, segment 9; I. Uncinus, segment 5; J. Uncini, segment 11; K. Uncini, segment 25. Scales: A, E, F, G: 2 mm; B, H: 0.2 mm; C, D, I, J, K: 0.05 mm.