Flabelligera picta Ehlers, 1913

Salazar-Vallejo, Sergio I., 2012, Revision of Flabelligera Sars, 1829 (Polychaeta: Flabelligeridae) 3203, Zootaxa 3203 (1), pp. 1-64 : 31-33

Flabelligera picta Ehlers, 1913

Figure 12

Flabelligera picta Ehlers 1913:532–533 , Pl. 40, Figs. 7–10 ; Hartman 1966:41, Pl. 12, Figs. 1–3 ; Hartwich 1993:128.

Type material. Antarctic Ocean. Paratype ( ZMH-8591 ), dried out ( Fig. 12F ), Kaiser Wilhelm II Land, Winter- Station, 350 m, German South Pole Expedition 1901–1903, det & leg Ehlers 1913 (black spots on most chaetigers) .

Additional material. Antarctic Ocean. One specimen ( ZMH-24295 ), R/ V Polarstern, Cruise ANT XV-3, Stat. 48-216 (71°06.3' S, 11°32.3' W), 211 m, multibox corer, 18 Feb. 1988 (used for description). One specimen ( ZIRAS-16415 ), in poor condition, preserving little dorsal pigment on anterior chaetigers, Davis Sea, close to Cape Mobus , XI Soviet Antarctic Expedition, R / V Ob, Stat. G, 40–45 m, rock, 2 Feb. 1966, Pushkin , diver, coll .

Description. Non-type specimen (ZMH-24295), broken in two, without posterior end, and without most of tunic ( Fig. 12A ). Body cylindrical, posteriorly tapered; with irregular, discontinuous, wide, dark, transverse band in all segments, continuing into chaetal lobe area, including chaetiger 1; with few other dispersed spots, larger dorsally ( Fig. 12B ) than ventrally ( Fig. 12C ); 21 mm (4.5+16.5) long, 1.5 mm wide, cephalic cage 2 mm long, 35 (8+27) chaetigers. Tunic thick, delicate, eroded, papillated; papillae thin, filiform, subdistally swollen, abundant (most previously removed, bases remain), without sediment particles.

Cephalic hood not exposed. Prostomium low cone, slightly pigmented; eyes not seen. Caruncle well developed, extended posteriorly, separating branchial lobes. Palps short, one left, colorless; palp bases rounded, elevated. Lateral lips massive; ventral and dorsal lips reduced.

Branchiae in two lateral groups, with about 20 filaments per group (most lost), arranged in rows; filaments about as long as palps, thinner. Nephridial lobes not seen.

Cephalic cage chaetae slightly longer than body width. Chaetiger 1 involved in the cephalic cage, about 20 noto- and about 24 neurochaetae (anterior end damaged). Anterior dorsal margin of chaetiger 1 smooth. Chaetigers 1–3 of about the same length. Chaetal transition from cephalic cage to body chaetae abrupt; chaetiger 2 with multiarticulated neurohooks. Gonopodial lobes not seen.

Parapodia well developed; lateral. Median neuropodia ventrolateral. Noto- and neuropodia long, subcylindrical lobes, each with many papillae. Noto- and neuropodia widely separated.

Median notochaetae arranged in short transverse rows. All notochaetae multiarticulated capillaries, at least twice as long as body width, about eight per bundle, articles very long ( Fig. 12D ). Neurochaetae multiarticulated capillaries in chaetiger 1; multiarticulated neurohooks from chaetiger 2 ( Fig. 12E ), mostly one per neuropodium. Handle articulation medially placed, articles irregular (in Fibonacci sequence); 2–3 articles: medium-sized, long, longer. Other articles anchylosed, small, continued to the bending region. Crest as wide as handle, homogeneously yellowish along the body; width:length ratio 1:6.0–7.5.

Posterior end (observed in ZIRAS-16415) tapered; pygidium with anus terminal, without anal cirri.

Remarks. Flabelligera picta Ehlers, 1913 differs from all other species in the genus because it has a discontinuous, irregular dark band on each segment, dorsally and ventrally, although along the venter the band becomes narrower and less pigmented. The original statement that neurohooks are longer than notochaetae ( Ehlers 1913:532– 533) was probably based on partially dried specimens, because in those cases, they appear to be as long as the longest notochaetae, or even longer, especially when the notochaetae are broken.

The holotype of F. picta was deposited in Berlin ( ZMB-5886 ) and is now lost ( Hartwich 1993). The original description states that this species was collected at three different stations, so probably the dried-out paratype deposited in Hamburg is the only original specimen available .

Distribution. Only known from the type locality in Kaiser Wilhelm II Land, and in the Davis Sea, Antarctica, in 40– 380 m.

Figures

FIGURE 1. Flabelligera affinis Sars, 1829. A. Non-type specimens (ZMUB-18636), dorsal view. B. Non-type specimen (MNHN- 184b), anterior end, dorsal view. C. Same, anterior end, ventral view. D. Non-type specimen (MNHN-184a), anterior end, most tunic removed, head exposed (Ca: caruncle, LL: lateral lip, NL: nephridial lobe, PL: palp lobe). E. Non-type specimen (ZMUB- 2253), lateral view, most tunic removed. F. Same, chaetiger 10, notochaetal basal and medial regions (insert: subdistal regions). G. Same, chaetiger 10, neurochaetae (inserts: articulated, median region and crest). Scale bars: A: 1.3 mm, B: 2.3 mm, C: 2 mm, D: 0.5 mm, E: 10 mm, F: 195 µm, G: 120 µm.

FIGURE 2. Flabelligera bicolor (Schmarda, 1861). A. Syntype (BMNH-1908.5.9.33), lateral view. B. Same, anterior end, lateral view. C. Another syntype (BMNH-1908.5.9.33), head, frontal view (BS: branchial scars, Ca: caruncle, LL: lateral lip, VL: ventral lip). D. Same, chaetiger 10, basal and medial notochaetal regions. E. Same, neurohook. F. Same, posterior chaetiger, neurohook (insert: handle articulation). Scale bars: A: 2.2 mm, B: 2.3 mm, C: 1 mm, D: 66 µm, E: 0.30 mm, F: 0.38 mm.

FIGURE 3. Flabelligera bophortica Annenkova-Chlopina, 1924, syntypes (ZIRAS-27043). A. Best syntype, lateral view. B. Same, anterior end, oblique, ventrolateral view. C. Same, head, frontal view (BS: branchial scars, Ca: caruncle, DL: dorsal lip, LL: lateral lip, PS: palp scar, VL: ventral lip). D. Same, neuropodia 4–7, oblique, ventral view showing gonopodial lobes (GL), E. Same, chaetiger 10, notochaetae (inserts: basal, medial and subdistal regions). F. Same, posterior chaetiger, neurohooks (inserts: handle articulation and crest close-up). Scale bars: A: 3.3 mm, B: 1.3 mm, C: 0.5 mm, D: 0.8 mm, E: 320 µm, F: 260 µm.

FIGURE 7. Flabelligera luctator (Stimpson, 1856), topotype specimens (BMNH-1936.10.16.152–7). A. Complete specimens. B. Largest syntype, anterior end, dorsal view. C. Same, head, frontal view (LL: lateral lip, NL: nephridial lobe, PS: palp scar). D. Same, chaetigers 4–7, ventral view (GL: gonopodial lobes). E. Same, chaetiger 5, neurohooks (insert: articulated portion of handle). F. Same, chaetiger 11, neurohook (insert: articulated portion of handle). Scale bars: A: 10 mm, B: 2.3 mm, C: 0.5 mm, D: 0.8 mm, E: 225 µm, F: 160 µm.

FIGURE 8. Flabelligera multipapillata Hartmann-Schröder, 1965, Holotype (ZMH-14911). A. Dorsal view. B. Anterior end, dorsal view; greenish due to methyl green staining. C. Same, chaetiger 12, neurohook (insert: basal and distal regions, enlarged). Scale bars: A: 1.7 mm, B: 0.6 mm, C: 150 µm.

FIGURE 9. Flabelligera nuniezi n. sp. A. Holotype (MNHN/1530), dorsal view. B. Same, ventral view. C. Same, chaetigers 3– 9, left neuropodia, showing gonopodial lobes by arrows. D. Same, chaetiger 10, neurohook. E. Same, chaetiger 22, neurohook. F. Non-type specimen (ZMUC unnumb.), median neurohook (insert: close up of handle anchylosed region). Scale bars: A: 1.3 mm, B: 1.1 mm, C: 0.2 mm, D: 90 µm, E: 100 µm, F: 250 µm.

FIGURE 10. Flabelligera orensanzi n. sp. A. Holotype (MACN-In 39270), dorsal view. B. Same, anterior end, ventral view. C. Paratype (CENPAT), head, frontal view, palps and branchiae removed, prostomium slightly eroded (BS: branchial scars, LL: lateral lip, PS: palp scar). D. Paratype (ECOSUR), chaetiger 9, neurohook (insert: articulated region of handle). E. Non-type specimen (MNHN-884), head, frontal view, two copepod parasites indicated by arrows (Ca: caruncle, BS: branchial scar, VL: ventral lip). Scale bars: A: 0.8 mm, B: 1 mm, C: 0.5 mm, D: 225 µm, E: 0.25 mm.

FIGURE 12. Flabelligera picta Ehlers, 1913. A. Non-type specimen (ZMH-24295), dorsal view. B. Same, anterior end, dorsal view. C. Same, anterior end, ventral view. D. Same, median chaetiger, notochaetae (inserts: basal and subdistal chaetal regions). E. Same, chaetiger 5, neurohooks (inserts: articulated regions and crests). F. Paratype (ZMH-8591), lateral view. Scale bars: A: 3 mm, B: 0.8 mm, C: 0.7 mm, D: 250 µm, E: 260 µm, F: 1 mm.