Peinaleopolynoe elvisi Hatch & Rouse sp. nov. Figures 6F-G, 7B, 10B, 12, 13

Type locality.

Whalefall in Monterey Canyon, California (36°46.33'N, 122°4.99'W), ROV "Doc Ricketts" Dive 99, 1820 m depth, 20 November 2009.

Material examined.

Type specimen: Holotype (SIO-BIC A8488) from a whalefall in Monterey Canyon, California (36°46.33'N, 122°4.99'W), ROV "Doc Ricketts" Dive 99, 1820 m depth, 20 November 2009; fixed in formalin and preserved in 50% ethanol, with elytra fixed and preserved in 95% ethanol. Paratypes: One specimen (SIO-BIC A9699) from bones deployed at Jaco Scar, Costa Rica (9°6.88'N, 84°50.14'W), HOV “Alvin” Dive AD4972, 1845 m depth, 18 October 2018; fixed in formalin and preserved in 50% ethanol, with elytra fixed and preserved in 95% ethanol. One specimen (MZUCR 1000-01) from bones deployed at Jaco Scar (9°6.91'N, 84°50.39'W), HOV “Alvin” Dive AD4976, 1887 m depth, 22 October 2018; fixed in formalin and preserved in 50% ethanol, with elytra fixed and preserved in 95% ethanol. Two specimens (SIO-BIC A9871, SIO-BIC A9870) from bones deployed at Seamount 1, Costa Rica (8°52.60'N, 85°7.34'W), HOV “Alvin” Dive AD4983, 2091 m depth, 29 October 2018; one fixed in formalin and preserved in 50% ethanol, with elytra fixed and preserved in 95% ethanol, and one fixed and preserved in 95% ethanol.

Description.

In life, large, overlapping, semi-transparent, iridescent 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. 7B). Twenty-one segments total (Fig. 12A, B). Elytra and elytrophores large, bulbous, nine pairs, on segments 2, 4, 5, 7, 9, 11, 13, 15, 17 (Fig. 12A). Elytra rounded to oval-shaped and slightly sub-reniform, very thin. Smooth edges along the circumference of elytra, except for a single rounded broad macrotubercle on posterior margin of elytra on segments 2, 4, 5, 7, 9, 11, 13, 15. Elytra on segments 2, 15, 17 ca. half the size of mid-body elytra. Elytra on segment 17 curving to a lateral point in live specimen (Figs 7B, 12D). Pharynx with a total of six dorsal and six ventral border papillae (Fig. 12C). 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. three times the length of prostomium (Fig. 12E). 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. 12E, F). Smooth ventral cirri on segments 2-21. Buccal cirri of segment 2 modified, with bulbous ceratophores (Fig. 12F) and longer styles. 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. 12B). Dorsal cirri present on non-elytrigerous segments 3, 6, 8, 10, 12, 14, 16, 18, 20, 21 (Fig. 12A). Cirrophores of dorsal cirri cylindrical, rather long, fused to posterior sides of notopodia. Styles of dorsal cirri filiform, long, extending beyond length of chaetae. Segment 19 modified, lacking dorsal cirri and elytrophores (Fig. 12I). Arborescent branchiae compact, with numerous short, bulbous terminal filaments, beginning on segment 3 (Fig. 12E) and continuing to segment 16 (Fig. 12I). 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. 12G). Branchiae on segment 3 not fully developed, but formation of two distinct bundles of branchiae still apparent on the left side (Fig. 12E). Four pairs of ventral segmental papillae on segments 12-15 (Fig. 12B). Ventral papillae rather long, slender, curved laterally and followed by two pairs of ventral lamellae (Fig. 12H). 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 extending to approximately the outline of the body (Fig. 12J). 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. 13A, B). Notopodia extending distally into acicular processes. Notochaetae forming radiating bundles, stout, with double rows of spines (Fig. 13C). Notochaetae almost as long as neurochaetae (Fig. 13A, B). Neurochaetae slender, forming fan-shaped bundles (Fig. 13A, B). Superior neurochaetae (supra-acicular) with double rows of spines (Fig. 13D). Inferior neurochaetae (sub-acicular) with double rows of teeth from the mid swelling to the hooked tips; smooth beneath the mid swelling (Fig. 13E). Inferior neurochaetae teeth are less prominent than the superior neurochaetae spines. Hooked jaws with small teeth on inner borders (Fig. 10B).

Morphological variation.

The holotype is 26 mm long, 15 mm wide, including chaetae. Paratypes range from 10-17 mm long, 7-9 mm wide, including chaetae.

Remarks.

Peinaleopolynoe elvisi sp. nov. is unique from the remaining Peinaleopolynoe taxa in having six pairs of border papillae on the pharynx (Table 5). Additionally, P. elvisi sp. nov. differs from its closest relatives P. santacatalina and P. sillardi in having branchiae start on segment 3, as opposed to on segment 2. Finally, the posterior margin of the elytra displays a single macrotubercle compared to the few found in the other species.

Etymology.

Peinaleopolynoe elvisi sp. nov. is named after the legendary King of Rock and Roll, Elvis Presley; the iridescent golden/pink elytra are reminiscent of the sparkly, sequined costumes he favored in his late career.

Ecology.

All specimens of P. elvisi sp. nov. were found associated with vertebrate bones or wood (Table 5). Fig. 6F shows the holotype observed in situ on sediment next to a whalefall just before collection. Fig. 6G shows paratype SIO-BIC A9699 observed in situ on a deployed pig bone before collection.