Siphonosoma cf. cumanense ( Keferstein, 1867 )

Silva-Morales, Itzahí & Gómez-Vásquez, Julio D., 2021, First records and two new species of sipunculans (Sipuncula) from the Southern Mexican Pacific, European Journal of Taxonomy 740 (1), pp. 77-117 : 83

Siphonosoma cf. cumanense ( Keferstein, 1867)

Fig. 3

Type locality of nominal species

Cumana, Venezuela ( Keferstein 1867: 53–55, pl. 6, figs 19–21).

Material examined

MEXICO • 1; Oaxaca, Huatulco, Santa Cruz Beach ; 15°45′10″ N, 96°07′49″ W; 1 Dec. 2016; JGV leg.; depth 3 m, in sand; UMAR-SIPU 104 .

Description

Pinkish and damaged trunk ( Fig. 3A ). Introvert and trunk with rectangular papillae ( Fig. 3D ). Approximately 80 peripheral tentacles of equal length ( Fig. 3C ). Without hooks. Musculature divided in 20 anastomosing longitudinal muscle bands ( Fig. 3B ). Two pairs of retractor muscles originating at same level along anterior-posterior axis. Dark brown nephridia occupying less than 10% of trunk. Villi present in contractile vessel. Spindle muscle attached to body wall posteriorly.

Remarks

This species is similar to Siphonosoma cumanense ( Keferstein, 1867) , but the widespread distribution is unlikely.

Habitat

Subtidal (3 m); in sand.

Distribution

Santa Cruz Beach, Oaxaca, Mexico.

Figures

Fig. 3. Siphonosoma cf. cumanense (Keferstein, 1867) from Oaxaca, Mexico. A. External morphology. B. Internal morphology.C. Peripheral tentacles.D. Folds of the body wall. Abbreviations: DRM = dorsal retractor muscles; I = intestine; LMB = longitudinal muscle bands; M = membrane of musculature; N = nephridium; T = tentacles; VRM = ventral retractor muscles.