Eumida delicata, Oliveira, Verônica Maria De, Eibye-Jacobsen, Danny & Lana, Paulo Da Cunha, 2015

Oliveira, Verônica Maria De, Eibye-Jacobsen, Danny & Lana, Paulo Da Cunha, 2015, Description of three new species of Eumida Malmgren, 1865 (Phyllodocidae, Annelida) from Southern and Southeastern Brazil, Zootaxa 3957 (4), pp. 425-440 : 437-439

Eumida delicata sp. nov.

Figs 13–15

Holotype. São Francisco do Sul, Santa Catarina State, Brazil, 26°16'52.0' N 48°40'38.3''W, 1.0 m, associated with lantern nets for oyster cultivation, 22 Mar 2013 ( ZUEC –16065).

Paratypes. 9 paratypes, all from Brazil, length ranging from 9 to 29 mm and number of segments ranging from 43 to 90. São Francisco do Sul, Santa Catarina State, Brazil, 26°16'52.0' N 48°40'38.3''W, 3 May 2013 (1 paratype, ZUEC –16066); Porchat Island Club, São Vicente, São Paulo State, 23°58'44.4''S 46°22'03.7''W, 15 Jun. 2003 (4 paratypes, ZUEC –16067); same locality, 11 Jul. 2013 (1 paratype, ZUEC –16068); Araça, São Paulo State, 15 Jul. 2003 (1 paratype, ZUEC –16069); Guarujá, São Paulo State, 4 Oct. 2005 (1 paratype, ZUEC –16070); Guara, São Paulo State, 5 Mar. 2007 (1 paratype, ZUEC –16071).

Diagnosis. Whitish pigmentation present dorsally on segment 2 (first visible segment) and cirrophores of dorsal tentacular cirri of segment 2. Dorsal cirri lanceolate, longer than wide, on median segments twice as long as wide, on posterior segments more slender.

Description. Holotype a complete female with 90 segments, 29 mm in length, 1 mm wide at median part of the body including parapodia and excluding chaetae. Body long, dorso-ventrally flattened and tapered at posterior end. Prostomium cordiform, clearly longer than wide, with rounded outline ( Fig. 13 A–B). Paired frontal, cylindrical antennae and palps of similar size. Antennae and palps half as long as prostomium. Median antenna located at anterior margin of eyes, reaching second segment ( Fig. 13 A–B). One pair of large black eyes located at posterior margin of prostomium. Undivided proboscis, with 6 longitudinal rows of clusters of papillae ( Fig. 13 C–E). Terminal ring of proboscis with 16 rounded papillae ( Fig. 13 C). First segment not visible dorsally. Four pairs of cylindrical tentacular cirri, biarticulate, arranged on first three segments. Tentacular cirri of segment 1 reaching segment 4. Dorsal and ventral tentacular cirri of segment 2 reaching segments 5 and 7, respectively. Dorsal tentacular cirri of segment 3 extending to segment 6. Neuropodia from second segment. Normal dorsal cirri with well-developed cirrophores without dorsal expansion, from segment 4; symmetrical and lanceolate, twice as long as wide on median segments, on posterior segments more slender ( Fig. 14 A–C). Prechaetal lobes bilobate, asymmetrical and rounded. Postchaetal lobes rounded. Normal ventral cirri horizontally oriented in relation to lobes, from segment 3, asymmetrical on anterior segments, oval on median segments and oval and elongated on posterior segments ( Fig. 14 A–D). Compound spinigerous chaetae from segment 2. Rostrum of chaetal shaft surrounded by denticles, article with serrated outer edge ( Fig. 15 A). Pygidium with one pair of long, slender, cylindrical anal cirri, reaching seventh posterior segment; pygidial papilla absent ( Fig. 15 B).

Colour. Living individuals with iridescent whitish pigmentation dorsally on segment 2 (the first dorsally visible segment) and the cirrophores of its dorsal tentacular cirri; other parts of the body olive to light green ( Fig. 13 A–C).

Habitat. Associated with lantern nets for oyster cultivation and intertidal and shallow subtidal consolidated bottoms.

Geographical distribution. Santa Catarina State and São Paulo State, Brazil.

Etymology. The species name is derived from the Latin word delicatus (delicate), referring to its delicate parapodial structures.

Remarks. This species differs from E. dracodermica sp. nov. in having lanceolate and elongate dorsal cirri along the entire body, whereas in the latter only those of posterior segments are lanceolate. The eyes are proportionally smaller in E. delicata sp. nov. than in E. macrophthalma sp. nov. The extension of the dorsal whitish pigmentation on the anterior segments in E. delicata sp. nov. clearly differs from that of E. dracodermica sp. nov. and E. macrophthalma sp. nov. (see Remarks on the latter species). All three new species described here share the insertion of the median antenna anterior to the eyes, but differ in its length, relatively long in E. delicata sp. nov. and E. dracodermica sp. nov. and shorter in E. macrophthalma sp. nov. It differs from E. sanguinea in the position of the median antenna and in the shape of the dorsal cirri, especially on anterior segments. E. delicata sp. nov. differs from Eumida notata (Langerhans, 1880) , known from Madeira, in the shape of the prostomium and dorsal cirri, which are oval and cordiform, respectively, in the latter. E. delicata sp. nov. shares dorsal lanceolate cirri and dorsal whitish pigmentation restricted to segment 2 with Eumida ockelmanni Eibye-Jacobsen, 1987 , known from northern Europe ( Denmark, Sweden, Norway, Great Britain, Faroe Islands), but differs from that species in its much larger size ( E. ockelmanni up to 7 mm long) and the absence of a median pygidial papilla.

Figures

FIGURE 13. Eumida delicata sp. nov. A—Prostomium and anterior end of living holotype, dorsal view; B—Prostomium and anterior end of fixed holotype, dorsal view; C—Overview of proboscis; D—E Distribution of papillae on the proboscis. Scales: A = 0.3 mm; B = 0.32 mm; C = 0.7 mm; D = 0.15 mm; E = 0.06 mm.

FIGURE 14. Eumida delicata sp. nov. Anterior view of parapodia from the holotype. A—Parapodium 5; B—Parapodium 24; C—Parapodium 57. D—Parapodium 85. Scales: A – C = 0.1 mm; D = 0.12 mm.

FIGURE 15. Eumida delicata sp. nov. A—Compound spinigerous chaeta; B—Anal cirri. Scales: A = 0.002 mm; B = 0.05 mm.