Eulalia aviculiseta Hartman, 1936

Pleijel, Fredrik, Aguado, Maria Teresa & Rouse, Greg W., 2012, New and lesser known species of Chrysopetalidae, Phyllodocidae and Syllidae from south California (Phyllodocida, Aciculata, Annelida), Zootaxa 3506, pp. 1-25 : 5-7

Eulalia aviculiseta Hartman, 1936

Figs 3 , 4

Eulalia aviculiseta Hartman, 1936: 122 , figs 1–6; 1961: 13; 1968: 259, figs 1–3; Pleijel 1991: 255.

Type material: 2 syntypes ( USNM 20341).

Material examined: California. 2 syntypes ( USNM 20341), Moss Beach, San Mateo County, coll. Hartman July 1933; 1 spm, preserved in formaldehyde (SIO-BIC A2595), La Jolla, pilons of Scripps Pier, 32°52.024’N, 117°15.437’W, 6 m depth, SCUBA, colls FP and GWR 25 Aug 2007; 1 spm, preserved in ethanol (SIO-BIC A2596), same collection data; 2 spms, preserved in ethanol (SIO-BIC A2597), Scripps Canyon, N of Scripps Pier, 32°52.411’N, 117° 15.515W, among tubes of Chaetopterus , 22–27 m, SCUBA, coll. Eddie Kisfaludy, 18 Feb 2010; 1 spm, preserved in ethanol, La Jolla, off Windansea Beach, 32°50.26’N, 117°17.11’W, 15 m, Macrocystis pyrifera holdfast, SCUBA, colls GWR & Phil Zerowsky, 15 Oct 2010 destroyed for DNA sequencing.

Description: Entire specimen 11 mm long for 67 segments. Live specimens yellowish with lime green dorsal and pygidial cirri and dark brown transverse band across each segment dorsally ( Fig. 3 ). Eyes ruby-red. Preserved specimens yellowish, lime green colouration absent, brown transverse bands fainter but visible. Body elongated cylindrical with tapering anterior and posterior ends, venter flattened. Prostomium rounded, about as wide as long ( Fig. 3 ). Palps and paired antennae tapering, pointed, inserted on distinct prostomial protuberance. Median antenna similar to paired antennae and palps, inserted medially on dorsal side of prostomium, well anterior to eyes. Eyes rounded, medium-sized. Nuchal organs not observed. Everted proboscis densely covered with diffusely distributed papillae, terminal ring with 18 smooth papillae (seen on single syntype only). Segment 1 fully developed. Dorsal cirri of segment 1 and ventral cirri of segment 2 reaching segment 5, dorsal cirri of segment 2 and segment 3 reaching segment 8 to 9. Ventral cirri of segment 2 flattened with small ventral wing ( Fig. 4 A). Chaetae from segment 3. Dorsal cirri of median segments flattened, lanceolate, more than twice as long as wide, near symmetrical along longitudinal axis, with pointed tips ( Fig. 4 B). Supraacicular lobes slightly larger but not longer than subacicular lobes ( Fig. 4 B). About 12 chaetae per fascicle. Rostrum of chaetal shafts with two prominent teeth bending towards each other, followed by series of teeth of decreasing size ( Fig. 4 C). Blades short, pointed, with serrated dorsal side. Ventral cirri flattened, conical, without distinct tips, extending slightly further than parapodial lobes. Pygidial cirri cylindrical with slightly inflated bases and long fine tips ( Fig. 3 ). Median pygidial papilla absent.

Habitat: Hartman’s original description makes no mention of habitat or depth, but the few newly collected specimens come from 6–27 m depth on either the pilons of Scripps pier or a bottom covered with Chaetopterus tubes.

Remarks: Banse (1972) synonymized E. aviculiseta with E. quadrioculata Moore, 1906 . We are at present not able to state if this is correct or not, but the two seem to be at least very closely related. Hartman’s species was from California, whereas Moore described his species based on specimens from Port Townsend in Washington, and new specimens should be collected from Moore’s type locality for both molecular and morphological comparisons with the Californian ones.

Hartman’s syntypes agree well with the newly collected specimens, although the pigmentation appears to differ in that her specimens lack mid-dorsal transverse bands, and instead have dark pigmentation on the border between the segments. This difference was also confirmed from re-examination of her types. We suggest that there may be one of three reasons for this: (1) the species described here is different from Hartman’s, (2) intraspecific variation, or (3) the differences are due to fixation. The sequence for COI we generated for E. aviculiseta (GenBank accession number JQ623496 ) showed a closest BLAST match to sequences of Eulalia levicornuta Moore, 1909 (GenBank HM473372 - HM473376 ), with a maximum identity of 87% and the sequence has an uncorrected pairwise distance of 16%. Other available COI sequences on GenBank for Eulalia species are for Eulalia mustela Pleijel 1987 (GenBank accession number AY996123 ) and Eulalia viridis (Linnaeus, 1767) (GenBank accession numbers e.g., AY996122 GU672585 ) each with an uncorrected pairwise distance of ~ 15–19%. One sequence listed as Eulalia viridis ( AY598732 ) does not appear to be of this taxon.

As seen from the morphology, E. aviculiseta belongs to the E. viridis group ( Kato et al. 2001) within Eulalia , having a comparatively fusiform body shape, lanceolate and slightly asymmetrical dorsal cirri and similar pygidial cirri. The transverse dorsal pigment bands across each segment and the lime-green colour are unique among Californian members of Eulalia (but see comments above re the syntypes and E. quadrioculata .

Figures

FIGURE 3. Micrograph of live, relaxed specimen of Eulalia aviculiseta (specimen used for sequencing). Scale bar 1 mm.

FIGURE 4. LM micrographs of Eulalia aviculiseta, (SIO-BIC A 2595). A, ventral cirrus segment 2. B, parapodium from median segment. C, chaetae from median segment. Scale bar A 200 µm, B 100 µm, C 50 µm.