Sabellastarte magnifica (Shaw, 1800)

Knight-Jones, Phyllis & Mackie, Andrew S. Y., 2003, A revision of Sabellastarte (Polychaeta: Sabellidae), Journal of Natural History 37 (19), pp. 2269-2301 : 2278-2280

Sabellastarte magnifica (Shaw, 1800)

(figure 3)

Tubularia magnifica Shaw, 1800: 228 , Jamaica, West Indies (neotype NHML 1998.932 ; topotypic specimens NHML 1912.2.28.1–3).

Sabella magnifica: Savigny (1822:78, Shaw’s record); Quatrefages, 1866: 443, Antilles, West Indies (MNHN A238, 297b); Fitzsimons, 1965, Barbados.

Sabellastarte magnifica: Augener (1922: 48) , Haiti, West Indies (ZMH V2880).

Sabella lingva, Krøyer, 1856: 27 , St Croix , West Indies (holotype ZMUC).

Sabella melania Schmarda, 1861: 35 , figure 188, Jamaica, West Indies (cotypes NHMW 1854, 1855).

Sabella splendida Kinberg, 1867: 353 Guadaloupe , West Indies (original material, NRM 1071, 1072): Johansson, 1925: 15, figure 5, Kinberg’s material).

Additional material. Antigua, English Harbour ( NHML 1931.6.22.60–62); Haiti, Port-au-Prince ( NHML 1938.11.29.49 as Laonome spectabilis ); Curacao, Caracas Bay ( ZMA V. Pol. 1272, seven specimens and 1273, three specimens as S. indica amongst Rhizophora on rocky shore, 0.1 m depth); Puerto Rico ( ZMA V. Pol. 1273 as S. magnifica ); Curacao, Piscadara Bay, Stn 1473 ( ZMA V. Pol. 4970, three specimens as S. indica ) amongst Rhizophora on rocky shore.

The neotype ( NHML 1998.932 ) figured and described here was chosen from four Jamaican specimens ( NHML 1912.2.28.1–4). Data in parentheses relate first to largest specimen of the topotypic series, the second to material from Antigua .

Description. Body without crown 75 (134, 86) mm long, 12 (12, 13) mm wide with about 150 segments (figure 3A) of which seven or eight are thoracic; crown 64 (67, 72) mm long, each side of crown base involuted ventrally to form nearly a circle each side, outer surface dark with pale longitudinal lines (in prolongation with radioles) giving appearance of indistinct corrugations, each dorsal margin with small D-shaped flange on level with small interradiolar web, length of web about equal to length of typical thoracic segment (figure 3B); radioles numerous (about 60 each side), frequently and randomly interdigitating, each rachis subquadrangular in crosssection (figure 3E, F, G), but with ridges on ‘outer’ radioles basally, close to web (figure 3D); radiolar tips short and blunt (figure 3H); dorsal lips long (15–20 mm), with midrib support, webbed to base of adjacent radiole but not to basal pinnule; thorax twice as wide as long, first segment scarcely longer than following thoracic segments (figure 3A, viewed from side and discounting height of collar); lateral collar margins transverse to axis of body and well above junction between crown and thorax (figure 3A), dorsal margins equally high and with notches above collar pockets defining well-developed dorsal lappets with rounded or undulating margins flanking dorsal midline (figure 3B), ventral collar forming two small triangular lappets, overlapping at midline (figure 3C); first ventral shield about 1.5 times as long as others in thorax, anterior margin fairly straight with midline embayment (figure 3C); anterior thoracic tori very long, anterior ones 1.3 times as long as segment seven, ventral ends of all tori touching sides of shields (figure 3C); tube, chaetae and uncini very similar to those of S. spectabilis except: (1) shafts of inferior abdominal chaetae much thicker (cf. figures 2M and 3L), (2) chaetae in thoracic fascicles more numerous (thoracic fascicle 6 with 116 chaetae) and (3) emergent parts of chaetae shorter, about equal to length of one thoracic shield (cf. figures 2P and 3P).

Neotype mostly brown with dark liver-brown on crown base, peristome, ventral shields and between uncinal ridges, paler areas being edge of collar, uncinal ridges, bands around crown and longitudinal lines on crown base; subtriangular dark brown marks dorsal to thoracic fascicles and ventral to abdominal fascicles, more diffuse pigment outside bases of dorsal collar pockets and towards anterior of midline groove. Interramal spots discrete and often distinct.

Habitat. The Antiguan Sabellastarte magnifica were abundant amongst red sponges and black tunicates on a dockyard sea wall ( NHML 1931.6.22.60–62) and are commonly found in crevices of coral (e.g. Maeandrina, ZMA V. Pol. 1272 ) or any hard substratum including Rhizophora in Curacao ( ZMA V. Pol. 1273).

Remarks and distribution. The only difference that Savigny (1822) gave between his Sabellastarte indica and S. magnifica was that the colour bands around the crown radioles are blackish brown in S. indica and red in S. magnifica , but such bands are variable and can be absent. Sabellastarte spectabilis is very similar to S. magnifica . The main differences found between the two species are that the inferior abdominal chaetae of S. magnifica are more stout and the thoracic fascicles protrude less from the thorax and have more chaetae. It also seems that large mature specimens do not reach the great size that S. spectabilis attains in favourable conditions. Two holdings identified as S. magnifica from the Philippines ( ZMH V 1790) and Mauritius ( NHML 1950.3.3.1) proved to be S. spectabilis and another from Mauritius ( ZMA V. Pol. 2394) is S. pectoralis . Sabellastarte magnifica may be confined to the tropical west Atlantic.