Spirobranchus minutus ( Rioja, 1941b )

Bastida-Zavala, J. Rolando, McCANN, Linda D., Keppel, Erica & Ruiz, Gregory M., 2017, The fouling serpulids (Polychaeta: Serpulidae) from United States coastal waters: an overview, European Journal of Taxonomy 344, pp. 1-76 : 54-56

Spirobranchus minutus ( Rioja, 1941b)

Figs 9 F–G, 10

Pomatoceros minutus Rioja, 1941b: 734–738 , pl. 9, figs 15–26 (type locality: Acapulco, Guerrero, Mexican Pacific; on the hydrozoan Pennaria ).

Serpulorbis catella Weisbord, 1962: 156–157 , pl. 13, figs 17–18 (fossil, type locality: Lower Mare and Abisinia formations, Venezuelan Pliocene and Pleistocene; on bivalve shell).

Pomatoceros minutus – Rioja 1942: 130–132, figs 15–21 (Mazatlán, Sinaloa, and Río Mayo, Sonora, Mexican Pacific; 15m;on shell of the bivalve Avicula sp.,now Pteria ).— Rioja1946:201–202 (Veracruz, eastern Mexico; on algae entangled in fishing nets). — Rioja 1947a: 215 (Gulf of California: Mapahui, Topolobampo and Navachiste, Sinaloa, Mexico). — Berkeley & Berkeley 1958: 405 (west coast of Baja California Peninsula: Abreojos Point, Baja California Sur; floating seaweed). — Weisbord 1964: 161–164, pl. 21, figs 4–5, pl. 22, figs 3–4 (recent, Playa Grande Yachting Club and Higuerote beaches, northern Venezuela; on several mollusk shells; and fossil, same as Serpulorbis catella ). — Zibrowius 1970: 15–16, pl. 3, figs 11–15 (São Sebastião and Ubatuba, Brazil; 6–15 m; on rocks, madrepores and gorgonians). — Shepherd 1972: 5 (Gulf of California: La Paz Bay, Baja California Sur; epifauna on Pinctada mazatlanica (Hanley, 1856)) . — Bastida-Zavala 1993: 35 (Gulf of California: Caimancito Beach, Baja California Sur). — Perkins 1998: 95 (checklist of shallowwater polychaetes of Florida). — Lewis et al. 2006: 669 (ten Hove collected specimens from the sailing vessel “Gorch Fock” in Sydney, Australia). — Bastida-Zavala 2008: 31–33 , fig. 7H–M (Hawaii, Mexican Pacific: Baja California Sur, Guerrero and Oaxaca, Pacific side of Costa Rica and Perú; intertidal to 17 m; on dead coral ( Pocillopora ), the gastropod Muricanthus , the oyster Spondylus , mangrove roots, sabellariid colony, on a pier piling and a sailboat hull).

Pomatoceros caeruleus (non Schmarda 1861) – Rioja 1963: 220 (Mexican Pacific: Mazatlán, Sinaloa, Guaymas, Sonora, and Zihuatanejo, Guerrero; on algae and mollusk shells).

Placostegus sp. – Bastida-Zavala 1995: 25 (Gulf of California: Cabo Pulmo Reef, Baja California Sur, Mexico; 4–17 m; on coral).

Pomatoleios crosslandi (non Pixell 1913) – Bastida-Zavala 1995: 25 (Gulf of California: Cabo Pulmo Reef, Baja California Sur, Mexico; 17 m; on coral).

Pomatoceros cf. minutus – Bastida-Zavala & Salazar-Vallejo 2000a: 814–815, fig. 5a–f (eastern Mexico: Cazones, Veracruz, and Campeche Bank, Campeche; 42 m).

Spirobranchus minutus – Pillai 2009: 146–148 (new combination). — Bastida-Zavala et al. 2016: 435 – 437, figs 8, 13H (Mexican Pacific: Baja California Sur, Michoacán, Guerrero and Oaxaca; intertidal to 1 m; in marinas and harbors, fouling).

Material examined

108 specimens: PB (59) Aug. 2002, GB (3) Sep. 2002, CC (46) Sep. 2002.

Additional material

Ten specimens: UMAR-Poly 73, several specimens (approx. 21°17' N, 157°50' W, Honolulu, HF-018, on the hull of a sailboat that traveled to Hawaii from San Francisco via Los Angeles, Mexico, Hilo, Hawaii and finally reached Honolulu; the entire travel period was four months, coll. S. Godwin); USNM- 43239, three specimens (Santa Catarina, Brazil, sta. 45 and 47, Nov. 1965, coll. Jones-Lowe).

Diagnosis

Tube white, with three longitudinal ridges and rows of alveoli between ridges; without peristomes ( Fig. 9F ). Opercular peduncle with thin distal wings, white ( Fig. 9G ). Operculum conical, with calcareous distal plate, with rounded tip ( Fig. 9G ). With 2–3 limbate collar chaetae, but sometimes lacking collar chaetae altogether; with a glandular spot in the position of the collar chaetae.

Taxonomic remarks

Spirobranchus minutus was recorded for the first time during our survey from the northern Gulf of Mexico (Galveston Bay and Corpus Christi, Texas) and Florida (Pensacola Bay).

In several specimens of S. minutus , the opercular peduncle lacks wings or has tiny wings. Another similar species in the northern Gulf of Mexico, S. americanus Day, 1973 , has a sublittoral (> 40 m) distribution. Spirobranchus americanus has more collar chaetae (4–6), a fully calcareous operculum, only one longitudinal ridge on the tube and has one line of alveoli on each side of the tube, while S. minutus has fewer collar chaetae (2–3) or lacks them completely, an operculum with a calcareous plate on a chitinous base, and the tube has three longitudinal ridges and two lines of alveoli on each side of the tube ( Fig. 9F ).

Ecology

Intertidal to 42 m ( Bastida-Zavala & Salazar-Vallejo 2000a). On rocks, on the hydrozoan Pennaria , mollusk shells ( Pteria sp., Pinctada mazatlanica , Muricanthus , Spondylus ), the coral Pocillopora , gorgonians, sabellariid colony, algae, mangrove roots, floating seaweed, on a marina pier piling and sailboat hulls ( Rioja 1941b, 1942, 1946; Berkeley & Berkeley 1958; Zibrowius 1970; Lewis et al. 2006; Bastida-Zavala 2008).

Distribution

Amphi-American. Eastern tropical Pacific, from Gulf of California to Perú; Hawaii; western tropical Atlantic, from Gulf of Mexico to southern Brazil ( Zibrowius 1970; Bastida-Zavala & Salazar-Vallejo 2000a; Bastida-Zavala 2008). In this study, Spirobranchus minutus was abundant on fouling plates from Pensacola Bay, Florida, and Corpus Christi, Texas, and was found occasionally on plates from Galveston Bay, Texas ( Fig. 10 ). This species extends its northward range from Cazones, Veracruz ( Bastida-Zavala & Salazar-Vallejo 2000a) to Pensacola Bay, Florida (1450 km).

Figures

Fig. 9. Serpulids from United States fouling plates. Serpula columbiana. A. Operculum, from Ketchikan Bay, Alaska (SERC-81981). B. Operculum, adult from San Diego, California (LACMNH-Poly4928);. – Spirobranchus kraussii. C-D. Operculum and tube fragment, from Oahu, Hawaii (SERC-114603). E. Colony, from Natal, South Africa (LACMNH-N5217). – S. minutus. F. Tube, from Santa Catarina, Brazil (USNM-43239). G. Operculum, From Tampa Bay, Florida (SERC-93759). Types of collar chaetae. H–J. Bayonet. K. Bayonet with proximal rasp. L. Capillaries. M. Limbate. N. Fin-andblade chaetae. O. Coarsely serrated. – Hydroides sanctaecrucis (H, L). – H. cf. brachyacantha (I). – Spiraserpula ypsilon (J). – H. elegans (K). – H. ochotereana (M).– Pseudochitinopoma occidentalis (N).– Ficopomatus uschakovi (O, modified from Arteaga-Flórez et al. 2014).

Fig. 10. Distribution of serpulids (Salmacina, Serpula and Spirobranchus spp.) from United States fouling plates (closed symbols) and literature records (open symbols).