Eunice filamentosa Grube & Orsted
Creators: name: Carrera-Parra, Luis F.
name: Salazar-Vallejo, Sergio I.
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Eunicida
Eunicidae
Eunice
Eunice filamentosa

description: Eunice filamentosa Grube & Örsted in Grube, 1856
Figure 1
Eunice filamentosa Grube & Örsted in Grube 1856:55 –56; Fauchald 1992:138 –140, Fig. 45a–g, Tabs. 33, 37; Carrera-Parra & Salazar-Vallejo 1998:1502, Figs. 4 g–l.
Material examined. Type material: Lectotype ZMUC-POL-00303. Saint Croix, Virgin Islands, 10 July 1847, col. Kröyer. Additional material: Gulf of Mexico, Mexico: Campeche, ECOSUR EUNI-1 XEN1(3), Punta Xen, in rock 20 m off shore, 24 May 2005, 1m. ECOSUR EUNI-1 HUE 1(10), El Hueso, in rock 50 m off shore, 25 May 2005, 2 m. Yucatán, ECOSUR-OH-P562 (1), 500 m off Punta San Felipe, 21°35ʹ9.99ʺ N, 88°13ʹ55.43ʺ W, in coralline rock, 16 Jun 2009, 3 m. ECOSUR-OH-P587 (1), 500 m off Punta San Felipe, 21°35ʹ9.99ʺ N, 88°13ʹ55.43ʺ W, in coralline rock, 16 Jun 2009, 3 m. ECOSUR-OH-P566 (1), 500 m off Punta San Felipe, 21°35ʹ9.99ʺ N, 88°13ʹ55.43ʺ W, in coralline rock, 16 Jun 2009, 3 m. ECOSUR-OH-P553 (1), Ria Lagartos, 1 km off Ria Lagartos beach, 21°37ʹ50.11ʺ N, 88° 9ʹ5.69ʺ W, in coralline rock, 14 Jun 2009, 2.5 m. ECOSUR EUNI-1 RIA 1(6), Off Ria Lagartos, 21°37ʹ16.7ʺ N, 88°10ʹ32.6ʺ W, in coralline rock, 30 May 2005, 3m. Caribbean, Mexico: Quintana Roo, ECOSUR-OH-P0157 (1), Isla Contoy, Puerto Viejo Lagoon, 21°29ʹ19ʺ N, 86°47ʹ32.1ʺ W, 24 Feb 2008, in sponge. ECOSUR-OH-P0158 (1), Isla Contoy, Puerto Viejo Lagoon, 21°29ʹ19ʺ N, 86°47ʹ32.1ʺ W, 24 Feb 2008, in sponge. ECOSUR-OH-P0162 (1), Isla Contoy, Puerto Viejo Lagoon, 21°29ʹ19ʺ N, 86°47ʹ32.1ʺ W, 24 Feb 2008, in sponge. ECOSUR-OH-P0166 (1), Isla Contoy, Puerto Viejo Lagoon, 21°29ʹ19ʺ N, 86°47ʹ32.1ʺ W, 24 Feb 2008, in sponge. ECOSUR-OH-P0172 (1), Isla Contoy, Puerto Viejo Lagoon, 21°29ʹ19ʺ N, 86°47ʹ32.1ʺ W, 24 Feb 2008, in sponge. ECOSUR-OH-P0182 (1), Isla Contoy, Puerto Viejo Lagoon, 21°29ʹ19.08ʺ N, 86°47ʹ32.16ʺ W, 24 Feb 2008. ECO- SUR EUNI-1 Buenavista(1) 18°30ʹ42ʺ N 87°45ʹ30ʺ W, in coralline rock, 27 Sep 1996, 1.5 m. ECOSUR EUNI-1 PA1(6), Punta Allen, 24 Feb 1986. ECOSUR EUNI-1 CCE1(5), Cayo cedros, Bahía Ascensión, 0 6 Mar 1987, in mangrove root. ECOSUR EUNI-1 CV9(4), Cayo Valencia, Bahía Ascensión, in mangrove root, 29 Apr 1987. ECOSUR EUNI-1 PH 9(4), Punta Hualastock, Bahía Ascención 28 Apr 1987. ECOSUR EUNI-1 HCH 1(1), Punta Hualalpich, Bahía Ascensión 27 Feb 1986. ECOSUR EUNI-1 (1) Punta Herrero, in coralline rock, 3 m. Caribbean, Trinidad & Tobago, UMML sta. P- 840 (2), 10°40ʹ N 60°37ʹ W, 45 km off NE of Trinidad, 1 Jul 1969, 33 m.
Description. Type material in poor condition (see remarks below). Complete specimen (ECOSUR-OH-158) with 292 chaetigers; L10 = 6.7 mm, W10 = 2.6 mm, TL = 12.4 cm. Anterior region of body with convex dorsum and flat ventrum; body depressed from chaetiger 16. Prostomium obviously shorter than peristomium, prostomial lobes frontally rounded, dorsally inflated; median sulcus deep (Fig. 1 A). Prostomial appendages in a horseshoe pattern, attached in prostomial furrow, median antenna isolated by gap. Palps about as long as antennae, digitiform, reaching middle of first peristomial ring. Antennae tapering, lateral and median antennae reaching beginning of first chaetiger. Palpophores and ceratophores short, wider than long, all of similar size. Palpostyles and ceratostyles without articulations. Eyes rounded, lateral, each between palp and lateral antenna. Peristomium with first ring five times longer than second ring, separation between rings dorsal and ventral; peristomial cirri tapering, short, reaching the middle of first peristomial ring, without articulation (Fig. 1 A).
Maxillary apparatus with five pairs and one single maxillae; MF = 1+1, 4+4, 7+0, 2+8, 1+1, –+–. MIII part of distal arc, blunt teeth of similar size. Left MIV with both teeth on distal end, followed by a long, edentate plate (Fig. 1 F). Right MIV with blunt teeth of similar size. MVI reduced to an edentate plate.
Branchiae from chaetiger 19 to last chaetiger, always longer and thicker than dorsal cirri; one branchial filament in chaetigers 19 to 45; then pectinate, increasing gradually up to four filaments from chaetiger 146 (Fig. 1 E). Prechaetal lobes inconspicuous, transverse fold in all chaetigers. Postchaetal lobes rounded in all chaetigers, very short, decreasing gradually until becoming inconspicuous. Chaetal lobes always longer than pre- and postchaetal lobes; auricular, longer portion dorsal, acicula emerging slightly dorsal to midline in anterior and median chaetiger; first 26 chaetigers with a papilla covering acicular tip. Last 107 chaetigers with chaetal lobes conical with acicula emerging by midline (Figs. 1 B–E).
Notopodial cirri without articulation, tapering; thicker in prebranchial region, becoming gradually thinner towards posterior parapodia, being four times thinner; all of similar length. Ventral cirri in chaetigers 1–4 digitiform, thick; in chaetigers 5–66 with swollen base, transverse welt with short digitiform tip; from chaetiger 67 digitiform, increasing in length to be longer in the last third of the body; always shorter than notopodial cirri (Figs. 1 B– E).
Chaetae limbate, supracicular; pectinate isodonts with up to 13 teeth in anterior chaetiger; heterodonts with up to 15 teeth in median and posterior chaetigers. Compound falcigers bidentate in anterior chaetigers, blade long and thin, proximal tooth triangular, shorter than distal tooth, directed laterally; distal tooth large, thin, directed upward (Fig. 1 G). Falcigers in posterior chaetigers similar in length as in anterior chaetigers but four times wider; proximal tooth much larger than distal tooth, directed laterally; distal tooth short, curved, directed slightly laterally (Fig. 1 H). Aciculae in chaetigers 1–19 amber, distal end expanded to one side (Fig. 1 J); in chaetigers 20–277 become darker with distal end translucent, laterally expanded, T-shaped (Fig. 1 K); from chaetiger 278 very thin, tapering, with small mucro (Fig. 1 L). Subacicular hooks from chaetiger 19, bidentate; dark with distal end translucent; less pigmented than aciculae. Proximal tooth much larger than distal tooth; strongly curved. Distal tooth straight, directed laterally (Fig. 1 M). Always one per chaetiger, except for replacements.
Pygidium with two pairs of anal cirri, without articulation; dorsal cirri as long as the last four chaetigers, ventral cirri very short.
Five of the specimens with L10 between 7.0 and 7.5 mm were mature females collected in February and April. The beginning of the oocytes was observed from chaetigers 61–75, with a diameter of 160–190 µm.
Variation. Material examined varied in L10 from 1.9 to 7.6 mm, and in W10 from 1.1 to 4.0 mm and varies in the following features: Subacicular hooks begin from chaetiger 16 to 23, branchiae start from chaetiger 19 to 25, and the last chaetiger with ventral cirri with swollen base varies from 33 to 66. Although there were few specimens, these features seem to be size-dependent. Further, there is a correlation between the start of subacicular hooks and branchiae, the former always start early. The maximum number of filaments was examined only in complete specimens because the best branchial development occurs in posterior chaetigers; there were 2–4 filaments per branchia, the higher number was present in specimens having L10 = 4.8 mm or larger. The number of teeth in some maxillae varied, without any size-dependence, as follows: MIII 6–7, MIV right 7–9.
Barcode. Nucleotide sequences between 522–645 bp of the section of COI gene used for barcoding were obtained from three specimens, one from the Gulf of Mexico (ECOSUR-OH-P562), and two from the Mexican Caribbean (ECOSUR-OH-P0166, ECOSUR-OH-P0172). The average evolutionary divergence over the three sequence pairs was zero.
Although in this case, we did not have access to specimens collected close to the type locality to be sequenced. However, we studied the lectotype and many specimens collected along 1200 km in the Yucatan Peninsula, some specimens from nearby localities and other ones from Trinidad and Tobago. All specimens share the same diagnostic features and we regard them as belonging to the same species. Further, the average evolutionary divergence over the three sequence pairs from specimens collected along the Yucatan Peninsula (Gulf of Mexico and Caribbean Sea) was zero. Consequently, we are confident that the sequenced specimens belong to E. filamentosa.
Remarks about type materials. The lectotype (ZMUC-POL-00303) is a complete small specimen in poor condition, with 119 chaetigers, L10 = 3.5 mm and W10 = 1.5 mm. However, the examination of the lectotype enabled us to clarify some issues given in the most recent redescription for the species (Fauchald 1992). Thus, the prostomial frontal lobe was described as obliquely truncate, tapering, dorsally flattened; however, the frontal lobes are rounded and dorsally swollen. Furthermore, the region with basally swollen ventral cirri was given as chaetigers 5–50, but this region is actually shorter, ranging from chaetiger 4 to 41. The lectotype has the three different shapes of aciculae as described above, not only the distally symmetrically hammer-headed shape as previously reported. Additionally, the pygidium was not described; although this structure is very damaged, it is possible to observe two pairs of anal cirri, the dorsal ones as long as the last four chaetigers, while the ventral pair is very short.
Distribution. Restricted to the Grand Caribbean Region. The records from the Tropical Eastern Pacific are regarded as an undescribed species (see below), whereas the reports for temperate areas in the Western Atlantic need to be confirmed.
description: Published as part of Carrera-Parra, Luis F. & Salazar-Vallejo, Sergio I., 2011, Redescriptions of Eunice filamentosa and E. denticulata and description of E. tovarae n. sp. (Polychaeta: Eunicidae), highlighted with morphological and molecular data, pp. 51-64 in Zootaxa 2880 on pages 53-56, DOI: 10.5281/zenodo.208034