Diplocirrus salazarvallejoi, Teixeira, Juliana Henrique, Rizzo, Alexandra Elaine & Santos, Cinthya Simone Gomes, 2015

Teixeira, Juliana Henrique, Rizzo, Alexandra Elaine & Santos, Cinthya Simone Gomes, 2015, Three new species of Diplocirrus Haase, 1915 (Polychaeta: Flabelligeridae) from Campos Basin in SE Brazil, Zootaxa 4027 (2), pp. 287-295 : 291-292

Diplocirrus salazarvallejoi sp. nov.

( Figure 2 A–C)

Type material. Brazil. Atlantic Ocean. Southeastern coast, Campos Basin. Holotype ( UERJ 5572-HAB8 E6 R3), 387.1 m, 31 January 2009, (22º 25' 54,966" S, 40º 17' 39,534" W).

Diagnosis. Sediment particles concentrated at the base of papillae, all of same size on ventral and dorsal regions, 6– 8 notochaetae and 4–5 neurochaetae per bundle throughout body, ventrolateral gonopores from chaetigers 3–12, notochaetae with small articles basally.

Description. Holotype incomplete; body cylindrical swollen along first 8 chaetigers, tapering in median and posterior region; 10 mm long, 1.2 mm wide, cephalic cage 1 mm long, for 20 chaetigers. Body whitish, tunic thin with papillae, fine sediment adhered to base of capitate papillae (longer than wide), all of same size on ventral and dorsal regions, up to 4 times longer on the lateral. Numerous rows of papillae on chaetiger 10. Longest papillae 1/5 as long as median notochaetae. Cephalic hood exposed, but anterior end features were either eroded or not visible. Cephalic cage chaetae ¼ as long as body width. Only notochaetae of chaetiger 1 form cephalic cage, 6–8 noto-and 4–5 neurochaetae per bundle. Notochaetae slightly longer in median and posterior region, 1/3 as long as body width, neurochaetae of the same length throughout body. From middle region, notochaetae twice as long as neurochaetae. Ventrolateral gonopores in chaetigers 3 to 12. Noto- and neurochaetae multiarticulate, articles of same size, finely tuned falcate tip. From chaetigers 1–13th, chaetae are twice longer than in following chaetigers.

Remarks. Diplocirrus salazarvallejoi sp. nov. is similar to Diplocirrus glaucus ( Malmgren, 1867) because both have long papillae on chaetal lobes, about 1/5 as long as median notochaetal length, anterior chaetigers longer than those that follow. Only notochaetae of chaetiger 1 are involved in cephalic cage. In contrast, Diplocirrus salazarvallejoi sp. nov. has: a) 6–8 notochaetae and 4–5 neurochaetae per bundle throughout body, b) ventrolateral gonopores from chaetigers 3–12, and c) notochaetae with short articles basally. Diplocirrus glaucus has a) 2–3 notochaetae and 0–1 neurochaetae in anterior chaetigers, 7–8 notochaetae and 4–5 neurochaetae in median chaetigers, b) gonopores not observed, and c) notochaetae with medium size articles basally. Previous records of D. glaucus may belong to this species.

Etymology. This species is dedicated to Dr. Sergio I. Salazar-Vallejo for his contribution to the study of polychaetes, especially the family Flabelligeridae , and for his encouragement and guidance to the first author (JHT) on the study of flabelligerids.

Distribution. Southeastern Atlantic coast, Campos Basin, Brazil, in soft bottom, only from 387 m depth.

Figures

FIGURE 2. Diplocirrus salazarvallejoi sp. nov. A. Holotype (UERJ 5572), anterior region in oblique lateral view and posterior in dorsal view. B. Same, chaetiger 10, notochaetae. C. Same, neurochaetae. Scale bars: A: 0.5 mm, B: 30 µm, C: 18 µm.