Pomatoceros minutus Rioja, 1941

Bastida-Zavala, J. Rolando, 2008, Serpulids (Annelida: Polychaeta) from the Eastern Pacific, including a brief mention of Hawaiian serpulids, Zootaxa 1722, pp. 1-61 : 31-33

Pomatoceros minutus Rioja, 1941

( Figures 7H–M)

Pomatoceros minutus Rioja, 1941b: 734–738 , pl. 9, figs. 15–26. Type locality: Acapulco, Guerrero, Mexico. Type speci-

mens lost. Pomatoceros minutus .— Rioja, 1942: 130–132 , figs. 15–21, Mazatlan (Sinaloa) and Rio Mayo (Sonora). Placostegus sp. — Bastida-Zavala, 1993: 25, Cabo Pulmo Reef (Baja California Sur). Pomatoleios crosslandi .— Bastida-Zavala, 1993: 25, Cabo Pulmo Reef (Baja California Sur). Pomatoceros cf. minutus .— Bastida-Zavala and Salazar-Vallejo, 2000: 814–815, figs. 5a–f, Veracruz and Campeche

Bank (Gulf of Mexico).

Material examined. More than 90 specimens: Hawaii (USA), UMAR-Poly 73, several spec. (approx. 21º17’N, 157º50’W, Honolulu, HF-018, from the hull of a sailboat from overseas to Hawaii, after of a voyage with the route San Francisco to Los Angeles to Mexico to Hilo, Hawaii to Honolulu; whole travel period was four months, coll. SG). Baja California Sur (Mexico), UMAR-Poly 74 (24º11’50”N, 110º18’02”W, playa Coromuel, Bahia de La Paz, sta. C24, June 24, 1986, coll. JALG, SISV); UMAR-Poly 75, 4 spec. (23º24– 25’N, 109º25’W, Cabo Pulmo Reef, second and third bar, on dead coral Pocillopora , 7–17 m, May 8 and Sept. 18, 1989, coll. PH, JK & JRBZ, as Placostegus sp. and Pomatoleios crosslandi ); USNM 48897, 10 spec. (approx. 24º15’N, 110º18’W, Bahia Falsa, Bahia de La Paz, Oct. 20, 1971, coll. W.M. Shepherd). Guerrero (Mexico), SV-pc, 50+ spec. (16º50’33”N, 99º54’39”W, Punta Manzanillo, Acapulco, Aug. 20, 1988, coll. SISV); UMAR-Poly 76 (16º50’N, 99º54’W, La Quebrada, Acapulco, on Muricanthus and Spondylus , May 25, 2000, coll. SISV, PSS & JRBZ). Oaxaca (Mexico), UMAR-Poly 77 (15º40’54”N, 96º27’55”W, La Boquilla, Puerto Angel, on bivalve shells, 6–10 m, Nov., 2003, coll. SS); UMAR-Poly 78 (15º45’12”N, 96º07’46”W, Santa Cruz bay, Huatulco, on pier pilots, 0–1 m, Nov. 12, 2003, coll. PZ); UMAR-Poly 79, 10+ spec. (16º14’10”N, 98º11’30”W, Laguna Corralero mangrove, on mangrove roots, 0–0.8 m, March 21, 2004, coll. JRBZ); UMAR-Poly 80 (16º12’59”N, 98º11’07”W, pier on mouth of Laguna Corralero, on sabellarid colony, 0–0.5 m, March 22, 2004, coll. JRBZ). Pacific coast of Costa Rica, LACM-AHF s.n. (9º14’40”N, 83º51’15”W, Dominical, Nov. 12, 1968, coll. D. Straughan). Peru, USNM 36578, 7 spec. (4º06’27”S, 81º03’41”W, Mancora, June 14, 1960, coll. W. Klawe).

Diagnosis. Tube white, with three longitudinal ridges and rows of alveoli between ridges, lacks peristomes ( Fig. 7H). Larger tubes with only ridge and lacking alveoli on the anterior section; inner tube surface rose or violet in colour. Opercular peduncle with thin distal wings, white or, sometimes, with brownish bands on peduncle and wings ( Figs 7I–M). Operculum conical, with calcareous distal plate, with rounded tip ( Fig. 7J) or, sometimes, with two rounded process ( Figs 7I–J, L). Thoracic membrane extends to last thoracic chaetiger. Collar with hooded (limbate) chaetae, in reduced bundles of 2–3 chaetae.

Habitat. Depth: 0– 10 m. In brackish-water lagoons on mangrove roots; in marine water on rock bottoms, dead coral Pocillopora , sabellariids colonies and molluscs shells. Fouling species.

Distribution. Amphi-American. Gulf of Mexico, Caribbean to Brazil; Hawaii Baja California Sur ( Mexico) to Peru ( Rioja 1941b; Rioja 1942; Bastida-Zavala 1993; Bastida-Zavala & Salazar-Vallejo 2000).

Taxonomic remarks. Several specimens of Pomatoceros minutus lack collar chaetae and may be mistaken with the Pomatoleios species. Within a single population of Pomatoceros minutus some specimens may have few collar chaetae and others have lost them completely; the same happens in other Pomatoceros species (Bastida-Zavala personal observation) and at least one Spirobranchus species , originally named as Olga Jones, 1962 and that belongs really to Spirobranchus giganteus (ten Hove 1970) .