Flabelligera luctator ( Stimpson, 1856 )

Salazar-Vallejo, Sergio I., 2012, Revision of Flabelligera Sars, 1829 (Polychaeta: Flabelligeridae) 3203, Zootaxa 3203 (1), pp. 1-64 : 22-24

Flabelligera luctator ( Stimpson, 1856)

Figure 7

Tecturella luctator Stimpson 1856:391 .

Pherusa tetragona Schmarda 1861:20 , Pl. 20, Fig. 168, Text fig. a–c.

Chloraema tetragona: Kinberg 1910:338 , Pl. 26, Fig. 2 .

Flabelligera marenzelleri McIntosh 1904:55–56 , Pl. 3, Fig. 26.

Flabelligera luctator: von Marenzeller 1888:15–16 , Pl. 1, Fig. 6 (n. comb., syn.); McIntosh 1904:53–55; Günther 1912:14; Augener 1918:452–454; Monro 1930:160.

Flabelligera affinis: Day 1961:505 , Fig. A; Day 1967:655, Figs. 32.1a–f (non Sars, 1829).

Material examined. South Africa. Nine specimens ( BMNH- 1936.10.16.152–7), six complete, three anterior fragments, Saint James, T.A. Stephenson, coll. (no further data). Two small specimens ( BMNH- 1930.10.8.24.78–79), Simon’s Town (no further data). (one specimen broken in two, both with well preserved outer cuticle); description below based on both lots, mainly on larger specimens. Two specimens ( LACM-AHF-2593 ), 24 Jul. 1938, J.H. Day, coll. Four specimens ( SMNH-95171 ), macerated, most tunic removed, R/ V Eugenie Expedition 1851–53, Stat. 1633 (34°30’ S, 18°30’ E), Cape of Good Hope, close to the lighthouses. One specimen ( SMNH-95172 ), macerated, most tunic removed, Durban (30° S, 31° E), Port Natal , no further data, Wahlberg, coll. (30 mm long, 3 mm wide, cephalic cage 3 mm long, 48 chaetigers). Six specimens ( SMNH-95173 ), macerated, tunic eroded with sand grains, R/ V Eugenie Expedition 1851–53, Stat. 1703 (34°30' S, 18°30' E), Cape of Good Hope, intertidal, Lighthouse .

Description. Topotype specimens (BMNH-1936.10.16.152–7); body brown, cylindrical, swollen medially, posteriorly tapering ( Fig. 7A ); 20–62 mm long, 2.0–4.5 mm wide, cephalic cage 2.3–4.0 mm long, 40–65 chaetigers. Tunic thick, transparent, papillated, mostly free from sediment coverage; papillae long, reddish, clavate, some mucronate.

Cephalic hood not exposed ( Fig. 7B ). Prostomium low cone, with four large brown eyes. Caruncle well developed, extended slightly beyond the branchial plate margin ( Fig. 7C ); medial lobe narrow, elevated, darker distally; lateral lobes depressed, pale. Palps long (three times longer than branchiae), tapering; palp bases elevated, rounded. Lateral lips well developed, widened; dorsal lip projected; ventral lip reduced.

Branchiae separated into two lateral groups, each group with branchial filaments in 7–8 rows; each group with about 100 filaments, decreasing in size ventrally; longer filaments about 1/3 as long as palps. Nephridial lobes conical, wide basally, tapering into short, thin, nephridial tubes.

Cephalic cage chaetae as long as 1/10–1/15 body length or about as long as body width. Chaetiger 1 involved in cephalic cage, with about 44 noto- and 36 neurochaetae. Anterior dorsal margin of chaetiger 1 papillated. Anterior chaetigers without especially long papillae. Chaetigers 1–3 decreasing in length posteriorly. Chaetal transition from cephalic cage to body chaetae abrupt; multiarticulated neurohooks from chaetiger 2. Gonopodial lobes in chaetigers 5 and 6, low, round, dark ( Fig. 7D ).

Parapodia well developed, lateral; median neuropodia ventrolateral. Notopodia foliose with darker elongate papillae. Neuropodia conical with darker elongate papillae. Noto- and neuropodia widely separated.

Median notochaetae arranged in short rows, transverse to body axis; all notochaetae multiarticulated capillaries, as long as long as half body width, 8–10 per fascicle, most with short articles, few with long articles. Neurochaetae multiarticulated capillaries in chaetiger 1; mostly single multiarticulated hooks from chaetiger 2. Handle articulation basally placed, articles roughly same length; three articles: two small, one medium-sized, sometimes with a transverse cleft ( Fig. 7E, F ). Other articles anchylosed, small, continuing to the bending region. Crest wider than handle, dark brown along the body, with darker distal half; width:length ratio 1:4–5.

Posterior end tapering to truncate cone; pygidium with terminal anus, pale or dark, muscular ring, without anal cirri.

Variation. The larger specimens (BMNH-1936) were severely damaged with detached tunics; about half the neurohooks and most of the cephalic cage chaetae were broken or lost because of the tunic removal. Body cylindrical, truncate at both ends, but four complete worms had a noticeable mid-body swelling, probably due to sediment in the gut. They were 47–62 mm long, 4.0–4.5 mm wide, cephalic cage 3–4 mm long (mostly broken), and 43–65 chaetigers. The body wall was more or less homogeneously pale brown, with darker pigment in the parapodia, and few specimens had a little more pigment in the ventral lip or in the anus.

Remarks. Flabelligera luctator ( Stimpson, 1856) is distinguished from other species with a transparent tunic and neurohooks provided with short crests (width:length ratio 1:4–5) because it has abundant, reddish or dark brown papillae. However, F. luctator has been regarded as closely allied with, and even a junior synonym of, F. affinis , but they differ because the former has a dark brown color and the neurohooks have crests slightly thicker than those present in F. affinis ; these differences were noticed by von Marenzeller (1888), McIntosh (1904), and Augener (1918). Further, Monro (1930) indicated that the subdistal swollen portion in each papilla differs in F.affinis and F. luctator , being longer in the former and shorter in the latter. The latter, unfortunate name F. marenzelleri was proposed by McIntosh (1904) as a new species; he added “an var. affinis ” and this explains why it has been listed as a variety. Regretfully, he restricted the comparison of his new taxon to F. affinis , and avoided any comparison with F. luctator , which was included in the same paper. Day (1967) included F. luctator under the synonyms for F. affinis . There is no type material available; regretfully, the poor condition of these specimens precludes any proposal of neotypes.

Figures

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 6. Flabelligera infundibularis Johnson, 1901. A. Lectotype (MCZ-2503), ventral view. B. Same, anterior end, dorsal view. C. Same, anterior end, ventral view. D. Paralectotype (LACM-AHF-535), head, frontal view (Ca: caruncle, LL: lateral lip, PS: palp scar, VL: ventral lip). E. Non-type specimen (USNM 186478), head, frontal view (BS: branchial scars, PS: palp scar). F. Lectotype, detached neurohook. G. Same, crest (insert: handle articulated portion). Scale bars: A: 7 mm, B: 2.4 mm, C: 2 mm, D, F: 0.5 mm, E: 1 mm, G: 112 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.