Polycirrus abrolhensis Garraffoni & Costa, 2003

Glasby, Christopher J. & Hutchings, Pat, 2014, Revision of the taxonomy of Polycirrus Grube, 1850 (Annelida: Terebellida: Polycirridae), Zootaxa 3877 (1), pp. 1-117 : 17-18

Polycirrus abrolhensis Garraffoni & Costa, 2003

Fig. 4a–d

Polycirrus abrolhensis Garraffoni & Costa, 2003: 3–5 , figs 1–4.

Type locality. Brazil, Abrolhos Archipelago .

Material examined. None.

Type material. HOLOTYPE: Brazil, Abrolhos Archipelago , 17°58ʹ44ʺ S, 38°42ʹ41ʺ W, 10 m, associated with calcareous algae, IBUFRJ-0481 . PARATYPES: all from Abrolhos Archipelago, IBUFRJ-0482 (16 specimens), IBUFRJ-0483 (5 specimens), MCEM-1303 (1 specimen).

Description. Holotype complete, 28 mm long, 0.55 mm wide for about 25 segments. Venter anteriorly with mid-ventral groove and discrete ventro-lateral pads; pads more-or-less smooth, extending from segment 3 ( Fig. 4a ). Mid-ventral groove from segment 3.

Buccal tentacles one type, cylindrical, thickened distally and distinctly grooved (some apparently missing), arising at junction between prostomium and upper lip. Upper lip prominent medial lobe with slight lateral expansions at base; oral surface glandular and ciliated. Outer lower lip subconical lobe protruding above venter, smooth ( Fig. 4a ).

Notochaetigerous segments 15, extending to segment 17. Notopodia digitiform, lobes distally flared, postchaetal lobe equal long to prechaetal ( Fig. 4c ). Notochaetae within a chaetiger one type, gradually elongating from dorsal to ventral, pinnate ( Fig. 4b ), posteriorly same form as those anteriorly. Neurochaetae beginning on segment 7, about 6–8 uncini per row. Uncini with long neck and concave base (Type 2); posterior ones about three times larger than anterior ones; teeth above main fang arranged in double transverse series (MF:1:8–10), enlarged median tooth above main fang present, subrostral process absent ( Fig. 4d ).

Nephridial papillae present. Pre-gular membrane nephridial papillae present on segment 4 only. Post-gular membrane nephridial papillae present, extending from segments 5–12; situated at ventral base of notopodia ( Fig. 4a ).

Comments. Polycirrus abrolhensis is similar to P. clavatus ( Kinberg, 1867) , which was described from the northeast coast of Brazil at 9°S in 33 m (18 fms). The two species appear to be differentiable based on the form of the ventro-lateral pads (discrete in P. abrolhensis ; poorly defined in P. clavatus ) and the distribution of nephridial papillae (on segment 4 only on P. abrolhensis ; segments 3 and 4 on P. clavatus ). Garraffoni & Costa (2003) did not compare their species with P. clavatus , which is only very briefly described by Kinberg (1867). The redescription of P. clavatus in this study clarifies the attributes of this poorly known species.

Figures

FIGURE 4. Polycirrus abrolhensis Garraffoni & Costa. a. Ventral view of head end. b. Anterior view of notopodium from anterior body. c. Notochaeta from anterior body. d. Lateral view of anterior uncinus. Scales a = 90 µm; b, d = 9.9 µm; C= 22.2 µm. (Modified after Garraffoni & Costa 2003, reproduced with permission from Zootaxa).