Nephasoma (Nephasoma) wodjanizkii wodjanizkii (Murina, 1973)

Gómez-Vásquez, Julio D., 2024, New records and five new species of sipunculans (Sipuncula) from the central and northwestern Mexican Pacific, European Journal of Taxonomy 925, pp. 179-219 : 193-194

Nephasoma (Nephasoma) wodjanizkii wodjanizkii (Murina, 1973)

Fig. 6B–E

Golfingia wodjanizkii Murina, 1973a: 944–945 , pl. 2 figs 5–6 (type locality: Alaska, 55°20ʹ05ʺ N, 134°49ʹ05ʺ W, depth 1100 m).

Golfingia nicolasi Thompson, 1980: 951–956 , fig. 2a–c (type locality: stn 813, San Nicolás Basin, California, depth 1754 m).

Golfingia wodjanizkii – Murina 1973b: 70 (Peruvian-Chilean trench, 1940–2000 m). — Frank 1983: 18–19 (west of Prince of Wales Island, Alaska, 55°20ʹ05ʺ N, 134°49ʹ05ʺ W, 42 m).

Nephasoma (Nephasoma) wodjanizkii wodjanizkii . – Cutler & Cutler 1986: 555–566, tab. 1 (new combination and synonymization). — Gálvez-Zeferino et al. 2020: 484, fig. 2c (Guerrero Negro Lagoon, Baja California; questionable record from a coastal lagoon).

Material examined

MEXICO – Baja California • 4 specs; W coast of Baja California , 28°47ʹ15ʺ N, 115°42ʹ57ʺ W; 1 Aug. 2013; depth 1045 m; core; TALUD XVI cruise, stn 4, on board R/V El Puma; EMU-13447 • 6 specs; W coast of Baja California, 29°08ʹ15ʺ N, 115°33ʹ43ʺ W; 24 May 2014; depth 1079 m; core; TALUD XVI-B cruise, stn 6, on board R/V El Puma; UMAR-SIPU 133 .

Description ( UMAR-SIPU 133)

Slim filiform body, trunk 24 mm in length ( Fig. 6B ); anterior half of trunk thinner. Smooth, light brown body wall, with short mammillate papillae. Introvert of same length as trunk; posterior end of introvert with approximately 30 longitudinal dark lines ( Fig. 6C ), extending anteriorly.

Longitudinal musculature continuous; two retractor muscles attached to body wall in posterior fourth of trunk ( Fig. 6E ). Two small nephridia, sack-like with pointed tip; nephridiopores open posterior to anus; free intestine ( Fig. 6D ).

Habitat

Bathyal (1045–2000 m); in muddy bottom.

Distribution

Eastern Pacific: from the Gulf of Alaska to the Peruvian-Chilean Trench. This is the first record of the species from the Mexican Pacific.

Remarks

The examined specimens of Nephasoma (N.) wodjanizkii wodjanizkii agree with Murina’s (1973a) original description. From the region, the closest record was made by Thompson (1980), who recorded the species for southern California.

Frank’s subsequent record from Canada should be revisited, since he made it based on a single specimen collected at a depth of 42 m ( Frank 1983). Furthermore, Gálvez-Zeferino et al. (2020) recorded N. (N.) wodjanizkii , similar to Frank’s record; it should also be revised, since they recorded a single specimen from a coastal lagoon on the western coast of Baja California Sur, at depths of 5 to 12 m. Two further studies, Murina (1973b) and Thompson (1980), collected their specimens at bathyal depths (1100– 2000 m) from the Peruvian-Chilean Trench and California, respectively; therefore, the present specimens from the western coast of Baja California represent an intermediate record of the species made in the marine ecoregion of the Northwest Warm Temperate Pacific.

Figures

Fig. 6. Golfingids. A. Golfingia (Golfingia) cf. muricaudata (EMU-13446). B–E. Nephasoma (Nephasoma) wodjanizkii wodjanizkii (Murina, 1973) (UMAR-SIPU 133). B. Lateral overview. C. Lateral view of posterior introvert. D. Internal anatomy. E. Close-up of retractor muscle origins from body wall. F. Themiste (Themiste) cf. blanda (ECOSUR-S0256). G. T. (T.) hennahi Gray, 1828 (ECOSUR-S0255). H. T. (T.) pyroides Chamberlin, 1920 (UMAR-SIPU 130). Abbreviations: see Material and methods. Scale bars: A = 2 cm; B, H = 2 mm; C, E = 1 mm; D, F = 4 mm; G = 3 mm.