ON RECENT SPECIES OF SPIRASERPULA REGENHARDT, 1961 



71 



Joris, muddy pebbles, Thalassia flat, few corals, from 

 limestone boulders, 30 cm, legit H. A. ten Hove, 

 10. ix. 1970, Stn.2096 (2 out of several specimens, BM(NH) 

 1992.20-24, RMNH 18175). 7. St. Jorisbaai, Koraal Tabak, 

 Punta Blanco, undersides of boulders, on rocky debris, 

 20-30 cm, legit H. A. ten Hove, 15. xi. 1988, 9. i. 1990, near 

 Stn. 75-30 (5 out of several specimens, MCZ, ZMH). 8. St. 

 Jorisbaai, entrance channel, W, boulders and large metal 

 poles in surf; from undersides crusts of Spiraserpula, legit 

 H.A. ten Hove, 16. i. 1990 (clusters, AM W20341, HUJ). 

 Aruba: 9. Spaans Lagoen, SE of bridge, rocks, etc., at 

 floodgate, mud, Rhizophora, 0-2.0 m, legit P. Wagenaar 

 Hummelinck, 24.iii.1970, Stn. 1673 (2 specimens BM(NH) 

 1992.12-13). 10. Andicuri, cape W of beach, windward 

 side, rockpool, exuberant coral growth, strong wave 

 action, 0.5 m, legit H. A. ten Hove, 20.viii. 1970, 

 Stn.2034B (several fragments of tubes, 2 incomplete 

 worms, ZMA V. Pol. 3719). 



Barbuda: 11. Great Lagoon, Lobster Point, N. of Palm 

 Beach, Thalassia and Halophila, 0-1.0 m, legit P. 

 Wagenaar Hummelinck, 23.vii.1967, Stn. 1534 (3 out of 

 several specimens, ZMA V. Pol. 3725). 

 Bonaire (Neth. Ant.): 12. Lac, dam, beachrock in current 

 behind surf, 5-10 cm, from crevices in beachrock, legit H. 

 A. ten Hove, 15.vii.1970, Stn. 2123 (1 specimen, USNM 

 130986). 13. Lagun, N shore, 500 m from entrance, rock, 

 boulders, 0-50 cm, from undersides of boulders, legit H. 

 A. ten Hove, 23. vi. 1970, Stn. 2129 (3 out of several 

 specimens, ZMAV. Pol. 3720). 14. Bonaire, Karpata, reef, 

 10 m, cryptic, legit H. A. ten Hove, 9.xi.88 (1 tube, 

 BM(NH) 1992.14). 



Jamaica: 15. Drunkeman's Key, sandy debris, 0-0.5 m, 

 legit P. Wagenaar Hummelinck, 15. vi. 1973, Stn. 1683, 

 (ZMA V. Pol. 3723). 



Puerto Rico: 16. La Parguera, E, glade in mangroves, 

 Thalassia beds, muddy sand, from between boulders, 

 20-30 cm, legit H. A. ten Hove, 1.x. 1970, Stn. 2135 (3 

 specimens, ZMA V.Pol. 3724). 



Panama: 17. Gatun Locks, walls of outer platform, lower 

 W chamber. Pan. Survey, 20.iii.1972, Pacific Stn. 81-1, M. 

 L. Jones coll., USNM No. 58661 (2 specimens without their 

 tubes). 18. Same, Stn. 81-2, M. L.Jones coll., USNM 

 No. 58662, (1 specimen with its tube). 



Florida: 19. Safe Harbour, Stock Island (near Key West), 

 Florida Keys, 5 m, from chunks of calcareous materials 

 (shells, barnacles, etc.) cemented together and covered 

 with serpulids and small cirratulids, legit R. Chesher and 

 C. Hamlin, 17.vii.1970 and l.vi.1971, Stn.7B, (22 out of 

 several specimens, USNM 130988, BM(NH) 1992. 15-19, 

 ZMAV. Pol. 3721 (10+ specimens from l.vi.1971). 20. Off 

 Egmont Key, 27. 0°37.0'N, 83°01.5'W, sea buoy, 18 m, 

 scarce sponges and corals, 2 cm of soft sludge on lime- 

 stone, many serpulids, legit H.A. ten Hove and T. Perkins, 

 2.U980, Stn. EJ. 80002, (9 out of several specimens, ZMA 

 V. Pol. 3722, FSBC I 39202). 



Type locality. Curasao (Netherlands Antilles). 



Description. 



tubes: Light to bright pink or rose coloured. They form 

 mutually bonded aggregations of a few to several individuals. 

 Their external diameter is generally about 1.0 mm, maxi- 

 mally 1.5 mm. There are three longitudinal ridges, one 

 median and one along each lateral margin, which may be 



indistinctly developed in places (Figs. 14, A; 15, A). Narrow 

 transverse ridges may be developed to various extents 

 (Fig. 15, A). Some of the tubes end anteriorly in 4 rounded, 

 anteriorly-directed lobes. A transparent to translucent granu- 

 lar overlay is present. The granulations are larger and more 

 densely laid along the ridges. The pink colour is faint along 

 the longitudinal ridges, as seen through the transparent 

 granules, but form of a pair of bright longitudinal bands 

 between the ridges. Branching tubes, difficult to observe 

 since they form dense aggregations, have been observed in 

 material from Curacao (Stn. 2090, 2096, 75-38), and from 

 Bonaire (Stn. 2123). 



ITS consist of a serrated ventral ridge along the concave 

 wall (Figs. 14, B,D; 15, P), and a smooth dorsal ridge 

 opposite (Figs. 14, B, D-F; 15, 0,P). The dorsal ridge is 

 nearly tongue-shaped in cross-section, with a gradual 

 decrease of its height, thickness and width of the widest part 

 both anteriorly and posteriorly. This is occasionally more 

 clearly seen in the non-coiled portions of tubes (Fig. 14, F). 

 The dorsal ridge may be situated on a columella-shaped axis 

 in tubes coiled upon themselves (Fig. 14, E). They usually 

 also possess a short accessory dorso-lateral ridge on either 

 side of the dorsal ridge (Figs. 14, B & C; 3, L). The inside of 

 the tube may have a light caramel to light brown lining. The 

 mid-ventral and mid-dorsal longitudinal abdominal grooves 

 of the worm are applied to the serrated ventral and smooth 

 dorsal ridges, respectively. 



worms: The longest available complete worm is from 

 Florida. It has a total length of 12.8 mm, thoracic width of 

 0.5 mm, abdominal length of 9.7 mm, and has 91 segments, 

 with capillaries commencing on the 80th. There are four 

 radioles and a rudimentary operculum on each side. Fully 

 developed opercula are absent in all the specimens, being 

 represented by a long and filamentous rudimentary opercu- 

 lum on each side (Fig. 14, H). The highest number of radioles 

 is 6 pairs, the longest measure about 2.1 mm, and end in 

 slender pinnule-free tips which are 1/5-1/6 their entire length 

 (Fig. 14, H). Radioles have up to 12 pairs of pinnules each, as 

 could be observed in living material. The smallest worm is a 

 juvenile from Curaco (Stn. 75-77) which has a total length of 

 3.7 mm, a thoracic width of 0.45 mm, abdominal length of 

 2.0 mm, and has 20 segments, with capillaries in the last 5. It 

 has 4 radioles on the left and 5 on the right, in addition to the 

 rudimentary opercula. 



Two reddish to reddish-brown clusters of prostomial ocelli 

 are present. The median lobe of the collar is sub-rectangular, 

 with rounded lateral borders and a smooth medial notch 

 (Fig. 14, I & J). Five to seven globular ventral thoracic glands 

 are present (Fig. 14, G), more or less arranged in a V. 

 Whether they are responsible for secreting the brownish 

 inner lining of the tube or not has to be further investigated. 



A summary of data is presented in Table 13. Similar data 

 from the Florida material are provided in Table 14. 



The bayonet collar chaetae, which number 3 or 4 fully 

 formed ones per fascicle and, usually, a developing one deep 

 within, are unique among the species of Spiraserpula and of 

 Serpula that have hitherto been described. Their blades are 

 conspicuously short, unserrated and dagger-shaped (Figs. 14, 

 K-M; 15, B-I, Q-W; P1.4, E & F). The number of large 

 conical teeth on the basal boss is usually 3 or 4. Often there 

 are 2 large teeth with 1 or 2 smaller ones in between (Fig. 14, 

 K-L; 15, B-I). In the specimens from Gatun Locks, Panama, 

 the number of teeth is usually 4 or 5 (Fig. 15, Q-W). These 

 dagger-shaped bayonet chaetae were noted and figured in the 



