Peinaleopolynoe goffrediae Hatch & Rouse sp. nov. Figures 6H, 7C, 10C, 14, 15
Type locality.
Whalefall in Monterey Canyon, California (36°36.79'N, 122°26.01'W), ROV “Tiburon” Dive 742, 2891 m depth, 29 September 2004.
Material examined.
Type specimen: Holotype (SIO-BIC A5485) from a whalefall in Monterey Canyon, California (36°36.79'N, 122°26.01'W), ROV “Tiburon” Dive 742, 2891 m depth, 29 September 2004; fixed in 95% ethanol and preserved in 50% ethanol, with a parapodium fixed and preserved in 95% ethanol. Paratype: One specimen (SIO-BIC A5464) from the same location as holotype; fixed in formalin and preserved in 50% ethanol, with posterior segments 16-21 fixed and preserved in 95% ethanol.
Description.
In life, large, overlapping, iridescent light pink elytra covering the dorsum. Dorsum with ciliated transverse bands extending onto bases of elytrophores and dorsal tubercles. Chaetae extending beyond the width of elytra (Fig. 7C). Twenty-one segments total (Fig. 14A, B). Elytra and elytrophores large, bulbous, nine pairs, on segments 2, 4, 5, 7, 9, 11, 13, 15, 17 (Fig. 14A). Elytra sub-reniform, thick; greatly textured along the posterior margin, with several pointed macrotubercles (Figs 7C, 14D). Elytra on segments 2, 17 ca. 50-75% the size of mid-body elytra (Fig. 7C). Elytra on segment 17 curving to a lateral point in live specimen (Fig. 7C). Pharynx with seven dorsal border papillae and six ventral border papillae (Fig. 14C). Bilobed prostomium with triangular anterior lobes bearing short, thin, very delicate lateral antennae (= minute frontal filaments, sensu Pettibone 1993). Smooth median antenna with bulbous ceratophore in anterior notch. Eyes lacking. Pair of thick, smooth, tapering palps, ca. two and a half times the length of prostomium (Fig. 14E). Segment 1 with dorsal and ventral pairs of smooth, tapering anterior cirri (= tentacular cirri, sensu Pettibone 1993), ca. the same length as palps. Ventral anterior cirri slightly shorter than dorsal anterior cirri. Cirrophores of anterior cirri long and cylindrical, each with small acicular lobe on inner side (Fig. 14E, F). Smooth ventral cirri on segments 2-21. Buccal cirri of segment 2 modified, with bulbous ceratophores and longer styles, ca. three and a half times the length of remaining ventral cirri (Fig. 14F). Buccal cirri attached to base of neuropodia. Ventral cirri on segments 3-21 attached to middle of neuropodia, with bulbous ceratophores and short, tapering styles (Fig. 14B, F). Dorsal cirri present on non-elytrigerous segments 3, 6, 8, 10, 12, 14, 16, 18, 20, 21. Cirrophores of dorsal cirri cylindrical, rather long, fused to posterior sides of notopodia. Styles of dorsal cirri long, extending beyond length of chaetae. Segment 19 modified, lacking dorsal cirri and elytrophores (Fig. 14I). Arborescent branchiae compact, with relatively long terminal filaments, beginning on segment 2 (Fig. 14E) and continuing to segment 17 (Fig. 14I). Branchiae forming single large groups on elytrigerous segments, attached to bases of notopodia. Branchiae forming two groups on cirrigerous segments; small groups attached to dorsal tubercles and large groups attached near bases of notopodia (Fig. 14G). Three pairs of thin rounded folds of unknown function attached to anterior sides of neuropodia on segments 8-10. Four pairs of ventral segmental papillae on segments 12-15 (Fig. 14B). Ventral papillae rather long, slender, curved laterally, and followed by two pairs of lamellae (Fig. 14H). Rounded ventral lamellae have similar orientation as papillae but flattened and not protruding as much toward posterior end. Pygidium with a pair of anal cirri, long but not extending beyond the outline of the body (Fig. 14J). Parapodia biramous. Neuropodia ca. twice the length of notopodia, with an acicular process. On cirrigerous segments, notopodia with dorsal tubercles possessing small bundles of branchiae (Fig. 15A, B). Notopodia extending distally into acicular processes. Notochaetae forming radiating bundles, stout, with double rows of spines (Fig. 15C). Notochaetae almost as long as neurochaetae. Neurochaetae slender, forming fan-shaped bundles (Fig. 15A, B). Superior neurochaetae (supra-acicular) with double rows of spines (Fig. 15D). Inferior neurochaetae (sub-acicular) with double rows of teeth from the mid swelling to the hooked tips; smooth beneath the mid swelling (Fig. 15E). Inferior neurochaetae teeth are less prominent than the superior neurochaetae spines. Hooked jaws with small teeth on inner borders (Fig. 10C).
Morphological variation.
Holotype is 39 mm long, 27 mm wide, including chaetae. Paratype is 43 mm long (segments 1-15), 26 mm wide, including chaetae.
Remarks.
Peinaleopolynoe goffrediae sp. nov.'s closest relative is P. orphanae sp. nov. (Fig. 1). Peinaleopolynoe goffrediae sp. nov. can be distinguished from P. orphanae sp. nov. by the segmental range of branchiae, the former present on segments 2-17 and the latter on segments 3-18 (Table 5). Additionally, the four pairs of ventral papillae on P. goffrediae sp. nov. are long, tapered, and curved laterally, distinguishing it from the small, rounded, cylindrical papillae of P. orphanae sp. nov. Peinaleopolynoe goffrediae sp. nov. is unique among Peinaleopolynoe taxa in that the angle formed by the ventral part on the neuroacicular lobe is clearly diagonal while it is nearly horizontal in the other species.
Etymology.
Peinaleopolynoe goffrediae sp. nov. is named after Dr. Shana K. Goffredi for her notable contribution to the exploration and research of deep-sea chemosynthetic ecosystems (especially whalefalls), focusing on symbiotic relationships between bacteria and marine invertebrates.
Ecology.
Peinaleopolynoe goffrediae sp. nov. was only found associated with a whalefall (Table 5). Fig. 6H shows the holotype observed in situ on a whale carcass before collection.