Neopsammolyce aff. floccifera (Augener, 1906)

Figs 2K–L, 11–12

Material examined

COLOMBIA • 1 incomplete spec.; off Caño La Balsa; 09°46′ N, 76°11′ W; R/V Pillsbury, Stn 393; depth 87 m; 16 Jul. 1966; UMML 6607-393 .

Description

BODY. Fragile, pale yellow, posteriorly translucent, long, broad (Fig. 11A), 56 segments, 2.3 cm long, 1.2 cm to segment 30, 0.4 cm wide. Middorsal line covered with sand grains attached to adhesive papillae (Fig. 11D). Venter covered with only pedunculate globular papillae (Fig. 11E).

PROSTOMIUM. Spherical. Two pairs of eyes, anterior eyes larger and covered by median antennal ceratophore (Fig. 11B). Lateral antennae small, bulbous, ceratophores as long as styles, dorsally fused with tentacular segment (Fig. 11F). Median antenna with bulbous ceratophore, slightly longer than prostomium, with dorsal ridges; style missing. Middorsal lobe of segment II with longitudinal ridge. Facial tubercle short, visible between palps (Fig. 11G). First segment directed anteriorly; fused with tentacular segment (right and left parapodia fused anteriorly); biramous, chaetae simple verticillate. Dorsal tentacular cirrus laterally displaced, longer than neuropodia including chaetae, ventral tetacular cirrus slightly shorter than dorsal one, but larger than neuropodia; palps short, reaching segment four, laterally displaced, with inner palpal sheaths (Fig. 11C).

ELYTRA. First right elytron missing. First left elytron oval, covered with few sand grains (Fig. 12E), with several kinds of papillae; elytral surface with flat papillae, and pedunculate papillae with flat tips, more abundant in elytral center; elytral margin with long and short dendritic papillae (Figs 2K–L, 12H). Second right elytron missing. Third right elytron slightly larger than first (Fig. 12F), same distribution and types of papillae as second elytra. Posterior elytra round, only one medial process (Fig. 12G, I–J), with same kind of papillae, but less abundant than anterior elytra (Fig. 12K).

RIGHT PARAPODIUM FROM SEGMENT II (Fig. 11H). Notopodia truncated, smooth (non-papillate), short, slightly shorter than neuropodia, notopodial flange leaf-shaped. With up to 50 simple verticillate notochaetae, shortest ones as long as notopodia, longest ones 3× as long (Fig. 11I). Neuropodia leafshaped, papillate, larger than notopodia. Neurochaetae only falcate falcigers: unit A, 18 falcigers with handles slender, covered by denticules, blades long soft, 75× as long as wide (Fig. 11J); unit B, four falcigers with handles slender, covered with denticules, blades long, 22× as long as wide (Fig. 11K); unit C and D undifferentiated, 11 falcigers with handles slender, covered by denticules, blades soft, long, 14 × as long as wide (Fig. 11L).

RIGHT PARAPODIUM FROM SEGMENT III (Fig. 11M). Notopodia truncated, smooth (non-papillate), short, ⅓ as long as neuropodia, notopodial flange leaf-shaped; notacicula missing. With up to 80 simple verticillate notochaetae, shortest ones as long as notopodia, longest ones twice as long (Fig. 11N). Neuropodia

conical, papillate, larger than notopodia. Neurochaetae only bifid falcigers: unit A, two falcigers with handles thick, with 5 transverse rows of spines, blades medium-sized, 8× as long as wide (Fig. 11O); unit B, four falcigers with handles thick, with 0–2 transverse rows of spines, blades medium-sized, 8× as long as wide (Fig. 11P); units C and D undifferentiated, 10 falcigers with handles with 3 barely perceptible transverse rows of spines, blades long, 15–19× as long as wide (Fig. 11Q).

RIGHT PARAPODIUM FROM SEGMENT 61 (MIDDLE SEGMENT) (Figs 11R, 12A). Notopodia truncated, smooth (non-papillate), short, ⅓ as long as neuropodia, notopodial flange round. With up to 80 simple verticillate notochaetae, shortest ones as long as notopodia, longest ones twice as long (Figs 11S, 12B). Neuropodia leaf-shaped, papillate, larger than notopodia. Neurochaetae only bifid falcigers: unit A, four falcigers with handles thick, with 3–6 transverse rows of spines, blades medium-sized, 8–9 × as long as wide (Figs 11T, 12C); unit B, five falcigers with handles thick, with 3 transverse rows of spines or denticles, blades medium-sized, 7× as long as wide (Figs 11U, 12D); unit C, three falcigers with handles thick, smooth, blades long, 10× as long as wide (Fig. 11V); unit D, three falcigers with handles slender, smooth, blades medium-sized, 6× as long as wide (Fig. 11W).

POSTERIOR REGION. Lost.

Remarks

Neopsammolyce aff. floccifera resembles N. floccifera (Augener, 1906) in a digitiform facial tubercle, a middorsal hump on segment II, and a ventral cirri papillate. However, N. aff. floccifera subtly differs by having first elytra small, as long as posterior ones, posterior elytra with long medial process, and neurochaetal blades bifid with subdistal tooth slender; while N. floccifera has a long first elytra, almost 2× longer than posterior ones, posterior elytra with a short medial process, and neurochaetal blades bifid with subdistal tooth thick. This specimen should be revised carefully in order to confirm its identity.

Distribution

Caribbean Sea. Colombia.