Phragmatopoma californica (Fewkes, 1889)

Figure 3 A–L

Sabellaria californica Fewkes, 1889: 34–36, pl. 7, figs. 3–4. Type locality: Coronado, California, intertidal, on rocks.

Sabellaria californica .— Moore 1909: 293–294, pl. 9, figs. 66a–b (San Diego and Monterey Bay, California); Chamberlin, 1918: 180 (Monterey Bay, California); Chamberlin 1919: 261 (Mendocino, California); Salazar-Vallejo & Londoño-Mesa 2004: 51 (checklist of polychaetes from tropical eastern Pacific).

Phragmatopoma californica (Fewkes, 1889) .— Hartman 1944: 349–350, pl. 29, figs. 15–17, pl. 37, figs. 86–89, pl. 41, fig. 105 (California; south of Ensenada, Baja California, intertidal— 73.2 m); Dales 1952: (La Jolla, California); Rioja 1963: 199 (Asunción Island, occidental cost of Baja California Sur, 21.9 m, on brown macroalgae, possibly Macrocystis sp.); Amieba et al. 1987: 260 (Sunset Cliffs, San Diego, California); Kirtley 1994: 28–31, figs. 2.2.1–2.2.3 (California, intertidal— 230 m); Hernández-Alcántara et al. 2003: 9 (Asunción and Coronado Islands, Baja California Sur); Salazar-Vallejo & Londoño-Mesa 2004: 51 (checklist of polychaetes from tropical eastern Pacific).

Material examined: eight specimens. Baja California: ECOSUR-P3081, six spec. (Punta San Miguel, Ensenada, 31°54’02”N, 116°43’46”W, March 21, 1982, coll. S.I. Salazar-Vallejo) ; ECOSUR-P3082, one spec. (Villa Las Rosas, Ensenada, 31°52’10”N, 116°40’39”W, on Phyllospadix sp., March 15, 1984, coll. S.I. Salazar-Vallejo) ; ECO-SUR-P3083, one spec. (Villa Las Rosas, Ensenada, 31°52’10”N, 116°40’39”W, March 6, 2004) .

Description. Color pattern of preserved specimens. Body pale yellow (Fig. 3A). Outer paleae with dark amber blade and handle; median plume translucent (Fig. 3E). Middle paleae cherry to light yellow from the nape toward the tip (Fig. 3 F–G). Inner paleae light amber (Fig. 3H). Opercular papillae yellowish with a light brown oval spot in the center. Median ridge with light brown eyespots. Tentacles, building organ, branchiae and the rest of the body pale yellow. Parathoracic chaetae yellowish (Fig. 3 I–J). Abdominal neurochaetae and uncini translucent (Fig. 3 K–L). Caudal peduncle yellowish to translucent toward distal part.

Body. Complete specimen of 19 mm total length; parathoracic region 3 mm wide; 34 abdominal segments; caudal peduncle 6 mm long (Fig. 3A).

Operculum. Opercular crown and opercular stalk completely fused (Fig. 3 A–B). Opercular crown conical and oval, slightly protruding in lateral view (Fig. 3 A–C). Three rows of paleae, only two visible: ~62 outer paleae, 27 middle and inner paleae. Outer paleae geniculate with a pair of heterodont teeth, one straight and lacerate, and the other curved; flat blade almost three times longer than wide, serrated margin and transversal thecae; median plume declined, short and flat, 1/3 as long as blade, hard proximally and covering of thin filaments entangled (Fig. 3E). Middle paleae strongly geniculate with declined peak, rough surface (Fig. 3G) and transversal thecae; sub-circular nape, straight, serrated, wider than peak, and large, 1/3 as long as peak; small chin, as long as wide, with margin slightly serrated; sharp tip curved (Fig. 3F). Inner paleae strongly geniculate with serrated peak straight, 11 times longer than wide; nape smooth; tip with filaments (Fig. 3H). Papillae small and oval. Oral tentacles unbranched. Median ridge small, 1/6 as long as opercular stalk, with marginal eyespots (Fig. 3D). Median organ absent. Building organ ‘U’- shaped.

Thorax. Chaetiger 1 with a pair of neuropodia.

Parathorax. Three parathoracic segments (Fig. 3A). Chaetigers with a pair of branchiae. Notopodia with lanceolate chaetae interspersed with small and smooth capillary chaetae (Fig. 3I). Neuropodia with lanceolate chaetae interspersed with small lanceolate chaetae (Fig. 3J); neurochaetae thinner than notochaetae.

Abdomen. Segments with a pair of branchiae decreasing in size towards posterior segments. Neurochaetae verticillate of different lengths (Fig. 3L). Notopodia with a series of uncini with six pairs of teeth (Fig. 3K).

Caudal region. Caudal peduncle elastic and slightly annulated (Fig. 3A).

Tube. Lost.

Variation. Body measurements varied from 13–33 mm total length, parathoracic region 0.5–3 mm wide and caudal peduncle 2–7 mm long (n= 8 spec.). The number of opercular paleae varied between ~ 50–76 in outer paleae and 25–41 in middle paleae. The abdominal segments varied from 15 in small specimens (13 mm total length) to 35–39 segments in the rest of specimens.

Habitat. Phragmatopoma californica can build large aggregations on rocks, forming massive reefs, from intertidal to 230 m (Fewkes 1889, Moore 1909, Hartman 1944, Kirtley 1994). Phragmatopoma californica aggregations may be associated with Thylacodes squamigerus (Carpenter, 1857), a reef-building vermetid mollusk (Hartman 1944), or with a sea grass ( Phyllospadix sp.).

Distribution. Eastern Pacific, from California to Coronado Island, Baja California Sur; these specimens were collected in Punta San Miguel and Villa Las Rosas, Ensenada, Baja California (Fig. 13).

Remarks. Phragmatopoma californica was recorded by Hartman (1944) from California to Ensenada, Baja California. The specimens were described with outer paleae with heterodont teeth, one straight and lacerate and the other curved, blade with transversal thecae and median plume plumose (Fig. 2 E–F); middle paleae with sub-quadrangular decurrent nape, peak slightly declined and blunted tip slightly falcate (Fig. 6A); and inner paleae slender, 11 times longer than wide, blade declined and tip with filaments (Fig. 6B).

The specimens found in Ensenada, Baja California, differ only in the morphology of the median plume in outer paleae: plumose in Hartman’s specimens (Fig. 2 E–F) and covered with thin downy in my specimens (Fig. 3E); and the shape of the nape in middle paleae: sub-quadrangular and decurrent in Hartman’s specimens (Fig. 6A) and subcircular and straight in our specimens (Fig. 3 F–G).

Phragmatopoma californica is distributed in template waters of the Eastern Pacific (Hartman 1944). For this reason, previous records of the species by Rioja (1942) from Mazatlán, Sinaloa and Acapulco, Guerrero, and by Kirtley (1994) from Panamá, are considered questionable because of their occurrence in warm waters, far from the typical distribution of species.