Polycirrus habitats Carrerette & Nogueira, 2013, sp. nov.
Creators: name: Carrerette, Orlemir
name: Nogueira, João Miguel De Matos
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Terebellida
Terebellidae
Polycirrus
Polycirrus habitats

description: Polycirrus habitats sp. nov.
(Figures 9–10; Tables 2, 6)
Type series. Holotype and paratype 1 coll. 07.Feb.2009 (21º56'7.560"S 39º57'51.306"W 720 m); holotype MZUSP 1221; paratype 1 MZUSP 1246.
Material examined. HABITATS /PETROBRAS Project: State of Rio de Janeiro—Campos Basin, Continental Slope/Canyons: 21º56'7.560"S 39º57'51.306"W, 720 m, 2 specs, coll. 07.Feb.2009.
Additional material examined for comparison. Polycirrus abrolhensis Garraffoni & Costa, 2003. Holotype: IBUFRJ–0481; paratypes 1: IBUFRJ–0482. Polycirrus glaucus Hutchings, 1993. Holotype: AM W20937; paratypes: AM W20966, 2 incomplete specimens.
Description. Middle-sized, anteriorly swollen worm (Fig. 9 A–B, D–I), abruptly tapering at segment 10–11, coiled after notopodia terminate. Holotype complete, with 57 (63) segments, 9.5 (10.1) mm long, 1.0 (0.8) mm wide (Table 6). Prostomium at base of upper lip, both basal and distal parts forming thick crests on dorsal surface of upper lip, crests laterally expanded, basal part extending posteriorly and ventrally, terminating laterally to mouth; swollen distal part of prostomium, restricted to base of upper lip; two types of buccal tentacles, long tentacles distally expanded, short tentacles uniformly cylindrical (Fig. 9 A–B, D–I). Peristomium restricted to lips (Fig. 9 A–B, D–I); thick upper lip, elongate, relatively narrow, densely ciliated (Fig. 9 G–H); lower lip with short, ciliated and grooved button and developed midventral shield, extending to anterior margin of segment 2 (Fig. 9 A, D, G–H). Segment 1 not conspicuous around body; segment 2 narrower than following segments. Rectangular, highly glandular, tessellated ventro-lateral glandular pads on segments 2–13, pairs separated by mid-ventral groove extending from segment 3, right after termination of lower lip (Fig. 9 A, D, G); pads progressively narrower from segment 10; wide groove on region with notopodia, progressively narrowing after termination of notopodia. Cylindrical notopodia extending to segment 17, with elongate, distally blunt post-chaetal lobe (Fig. 9 A, F–I). Pinnate notochaetae on both rows, gradually tapering to tips (Fig. 10 A–B, E). Neuropodia beginning from segment 9; anterior neuropodia as short, sessile tori, progressively more developed posteriorwards, as prominent pinnules on posterior chaetigers. Neurochaetae type 2 uncini sensu Glasby & Glasby (2006) (Fig. 10 C–D; F–I), higher than long, with short dorsal button near base of main fang, and crest with two rows of secondary teeth, first row with long, single tooth, upper row with tiny teeth around base of tooth from basal row. (Fig. 10 C–D; F–I). Nephridial and genital papillae present on segments 3–11. Pygidium surrounded by rounded papillae, larger ventral papilla, small papillae lateral and dorsally (Fig. 9 C).
Remarks. Polycirrus habitats sp. nov., belongs to Group 2A sensu Glasby & Glasby (2006) for having type 2 uncini together with pinnate notochaetae. To this group also belong P. abrolhensis Garraffoni & Costa, 2003, P. aquila Caullery, 1944, P. clavatus (Kinberg, 1866), P. coccineus (Grube, 1870), P. glaucus Hutchings, 1993, and P. medius Hessle, 1917. Among all those, P. abrolhensis and P. clavatus were originally described from Brazil, and P. coccineus has already been recorded from the Brazilian coast (Nonato 1981; Paiva 1990, 1993; Duarte 1980; Morgado 1980), but it is unlikely to occur in Brazil, as its type locality is in the Red Sea (see Table 1).
Polycirrus abrolhensis was described from Abrolhos Archipelago, Brazil, and shares several characters with P. habitats sp. nov., such as elongated, distally tapering notopodia, similar number of pairs of notopodia (Tables 1–2), and dorsal surface slightly wrinkled on the segments of region with notopodia. On the other hand, P. abrolhensis differs from P. habitats sp. nov., in the morphology of the upper lip, the segment on which the first pair of neuropodia appears, and the number of nephridial and genital papillae (Tables 1–2). Polycirrus abrolhensis has trilobed upper lip with convoluted lateral lobes, neuropodia beginning from segment 8, and nephridial and genital papillae on segments 4–12 (Table 1). Polycirrus habitats sp. nov., in contrast, has elongate and narrow upper lip, not clearly folded into three lobes, neuropodia beginning on segment 9, and nephridial and genital papillae on segments 3–11 (Table 2).
Polycirrus aquila was originally described from the Malay Archipelago, Southeastern Asia, and according to Holthe (1986a) has been recorded from several localities in the Indo-Pacific. Polycirrus aquila differs from P. habitats sp. nov., in having 16 pairs of notopodia, neuropodia beginning from segment 16, and nephridial and genital papillae on segments 3–17 (2–16 according to Holthe 1986a, but we believe this is due to miscounting of anterior segments) (Table 1).
Polycirrus clavatus was described from Rio de Janeiro, Brazil, from a specimen in poor condition (Kinberg 1867). According to Glasby & Glasby (2006), P. clavatus differs from P. habitats sp. nov., by having notopodia extending until segment 14 and neuropodia beginning from segments 4–5 (Table 1).
Polycirrus coccineus was originally described from the Red Sea and has also been recorded from Brazilian waters by Nonato (1981, as Polycirrus cf. coccineus) and later by Paiva (1990, 1993). However, according to the literature, Brazilian specimens differ from those from the type-locality as the latter have 19 pairs of notopodia, bearing only pinnate notochaetae, and neuropodia beginning from the penultimate segment with notopodia, i.e., segment 20 (Table 1), while the Brazilian specimen described by Nonato (1981) was incomplete, with only 14 chaetigers, bearing pinnate and limbate notochaetae, and neuropodia were absent. Polycirrus habitats sp. nov., differs from both “variations” of P. coccineus in the number pairs of notopodia and the segment on which neuropodia begin (Tables 1–2).
Polycirrus glaucus was originally described from Western Australia and differs from P. habitats sp. nov., in having notopodia extending to segment 11, i.e., only 9 pairs of notopodia, and neuropodia beginning from segment 14 (Hutchings 1993; Glasby & Glasby 2006; JMMN personal observation) (Table 1).
Finally, P. medius was originally described from Japan and has never been found outside of the type-locality (Holthe 1986). According to the original description (Hessle 1917), P. medius differs from P. habitats sp. nov., in having 16 pairs of notopodia, and neuropodia beginning from segment 16 (Table 1).
Etymology. We name this species in apposition to " Habitats Project" (“Environmental Heterogeneity in the Campos Basin”), in accordance with the International Code of Zoological Nomenclature, art. 34.2.1 (ICZN 1999). “ Habitats Project” immensely improved the knowledge on the marine fauna occurring off the Brazilian coast, including several deep-sea habitats.
description: Published as part of Carrerette, Orlemir & Nogueira, João Miguel De Matos, 2013, Four new species of Polycirrus Grube, 1850 (Polychaeta: Terebellidae) from Campos Basin, southeastern Brazil, pp. 146-172 in Zootaxa 3626 (1) on pages 166-170, DOI: 10.11646/zootaxa.3626.1.6, http://zenodo.org/record/218715