Myrianida dentalia (Imajima 1966)

Salcedo, Diana L., Martín, Guillermo San & Solís-Weiss, Vivianne, 2016, Eusyllinae, Exogoninae and Autolytinae (Syllidae: Polychaeta) from the Southern Mexican Pacific, with the description of three new species, Zootaxa 4158 (4), pp. 507-522 : 520-521

Myrianida dentalia (Imajima 1966)

Autolytus (Autolytus) dentalius: Imajima, 1966b: 36 –37, Fig. 7 I–L.

Autolytus dentalius: Gardiner, 1976: 127 , Fig. 10A–D.— Uebelacker, 1984: 30 -12, Fig. 30-4A-D.— San Martín, 2003: 505 – 507, Figs 280–281.

Myrianida dentalia: Nygren, 2004: 127 –128, Fig. 61A–D.

Material examined. 60 specimens (CNAP–ICML PO-37-104): 1 specimen, Caleta E1B2, 16°49.797’N, 99°54.062’W, May 25 2006, 12 m, coarse sand. 2 specimens, Palmitas E2B1, 16°42.420’N, 99°54.733’W, May 25 2006, 10.5 m, coarse sand. 5 specimens, Palmitas E2B2, 16°42.420’N, 99°54.733’W, May 25 2006, 10.5 m, coarse sand. 12 specimens, El Jardín E3B1, 16°49.436’N, 99°54.981’W, May 26 2006, 12 m, coarse sand. 40 specimens, El Jardín E3B2, 16°49.436’N, 99°54.981’W, May 26 2006, 12 m, coarse sand.

Remarks. The specimens herein examined presented some differences with the original description of the species. The trepan has approximately the same number of teeth, but the arrangement is somewhat different since it has 15 teeth both in the dorsal and ventral parts, while in the original description of M. dentalia it is stated that it has 9 to 11 dorsal teeth and between 16 and 19 ventral teeth. In addition, in the specimens from Acapulco Bay, the proventricle is shorter (extending through 8 segments), with a lower number of muscular cell rows (around 26). The remaining characters agree well with the species originally described, so that, considering the difficulties and subjectivity involved in the distinction of the teeth of the trepan, we decided to consider that all the examined specimens belong to M. dentalia .

Habitat. Subtidal, living between hydroids, bryozoans and tunicates in coarse sand.

Distribution. Japan, North Carolina ( USA), Gulf of Mexico and Southern Mexican Pacific (Acapulco Bay).

Figures

FIGURE 7. Prosphaerosyllis sotoi n. sp. (A) Posterior chaetae. (B) Dorsal simple chaeta (C) Ventral simple chaeta. Scale = 40 µm.