Eumida dracodermica, 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 : 428-433

Eumida dracodermica sp. nov.

Figs 6–9

Holotype. Saco do Limoeiro, Mel Island, Paraná State, Brazil, 25°33’37.8”S 48°18’03.0”W, in the intertidal region, 28 Oct. 2010 ( ZUEC –16049).

Paratypes. A total of 42 paratypes, length ranging from 2 to 37 mm and number of segments ranging from 18 to 92. Continental shelf in Campos Basin, Brazil: Hab11 E02 R1, 22º6'56.2"S 40º38'58.2"W, 53 m, 26 Feb. 2009 (4 paratypes, ZUEC –16050); Hab17 Foz09 R2, 22º11'30.6"S 40º55'24.4"W, 44 m, 17 Jul. 2009 (2 paratypes, ZUEC – 16051); Hab17 Foz09 R1, 22º11'30.6"S 40º55'24.4"W, 44 m, 17 Jul. 2009 (2 paratypes, ZUEC –16052); Hab11 C02 R3, 22º37'31.8"S 41º21'51.8"W, 53 m, 27 Feb. 2009 (1 paratype, ZUEC –16053); Hab17 Foz09 R1, 22º11'30.6"S 40º55'24.4"W, 44 m, 17 Jul. 2009 (3 paratypes, ZUEC –16054); Hab16 B04 R3, 23º10'5.0"S 41º3'7.5"W, 107 m, 2 Jul. 2009 (1 paratype, ZUEC –16055); Hab11 E2 R3, 22º6'55.6"S 40º38'58.3"W, 53 m, 2 Jul. 2009 (2 paratypes, ZUEC –16056); Hab11 B2 R3, 22º12'53.4"S 40º51'12.4"W, 52 m, 26 Feb. 2009 (1 paratype, ZUEC –16057); Hab17 Foz21 R1, 22º6'22.0"S 40º43'42.3"W, 47 m, 17 Jul. 2009 (4 paratypes, ZUEC –16058); Hab11 D1 R3, 22º6'42.2"S 40º54'44.3"W, 29 m, 26 Feb. 2009 (2 paratypes, ZUEC –16059); Hab13 Foz21 R3, 22º1'9.9"S 40º31'54.4"W, 49 m, 12 Mar. 2009 (1 paratype, ZUEC –16060); Hab13 Foz9 R3, 22º11'32.1"S 40º55'24.1"W, 44 m, 13 Mar. 2009 (1 paratype, ZUEC –16061); Hab13 Foz2 R1, 22º6'21.2"S 40º43'39.3"W, 47 m, 12 Mar. 2009 (6 paratypes, ZUEC – 16062); Hab13 Foz21 R3, 22º6'21.9"S 40º43'39.4"W, 47 m, 12 Mar. 2009 (3 paratypes, ZUEC –16063); Hab11 E2 R1, 22º6 56.2"S 40º38' 58.2 W, 53 m, 26 Feb. 2009 (1 paratype, ZUEC –16064); Hab13 foz29 R1, 21°24'43.621"S, 40°25'18.618"W, 33 m, 3 Jul. 2009, (2 paratypes, ZMUC-POL-2363); Hab11 E02 R03, 22º6'55.6"S, 40°38'58.3"W, 53 m, 26 Feb. 2009, (6 paratypes, ZMUC-POL-2364).

Diagnosis. Whitish pigmentation present dorsally on segment 2 (first dorsally visible segment), posterior edge of prostomium, anterior edge of segment 3 and cirrophores of dorsal tentacular cirri of segments 2 and 3. Dorsal cirri on anterior and median segments cordiform, almost as wide as long, on posterior segments lanceolate.

Description. Holotype a complete female with 92 segments, 37 mm long, 2.5 mm wide at the median part of the body, including parapodia and excluding chaetae. Body long, dorso-ventrally flattened, with tapered posterior end. Prostomium cordiform to pentagonal, clearly longer than wide, with rounded outline. Paired frontal, cylindrical antennae and palps of similar size. Antennae and palps about as long as prostomium. Median antenna located on median part of prostomium, at anterior margin of eyes, reaching fifth segment ( Fig. 6 A–B). One pair of red eyes, of medium size, located at posterior margin of prostomium. Undivided proboscis, with 6 longitudinal rows of tubercles and micropapillae ( Fig. 6 C). Terminal ring with 18 rounded papillae; each papilla with two longitudinal rows of micropapillae ( Fig. 6 F–E). First segment not visible dorsally. Four pairs of cylindrical tentacular cirri, biarticulate, located on first three segments. Tentacular cirri of first segment reaching segment 4.

Dorsal and ventral tentacular cirri of segment 2 reaching segments 10 and 4, respectively. Dorsal tentacular cirri of segment 3 extend to segment 10. Neuropodia from second segment. Normal dorsal cirri symmetrical, with welldeveloped cirrophores without dorsal extensions, from segment 4. Dorsal cirri of anterior and median segments cordiform, with distal extremities more tapered, almost as wide as long, on posterior segments lanceolate. Prechaetal lobes bilobate and rounded, supracicular lobe twice as large as subacicular lobe. Postchaetal lobes rounded. Normal ventral cirri horizontally oriented in relation to lobes, present from segment 3, on anterior and median segments rounded, on posterior segments more elongate, almost lanceolate ( Fig. 7 A–C). Compound spinigerous chaetae, from segment 2. Chaetal rostrum surrounded by rows of conical denticles, article with serrated outer edge ( Fig. 8 A–C). Pygidium with one pair of conical, short anal cirri. Pygidial papilla absent ( Fig. 9 A–B).

Colour. Living individuals with iridescent whitish pigmentation dorsally on segment 2 (the first dorsally visible segment), the posterior edge of the prostomium, the anterior edge of segment 3 and the cirrophores of the dorsal tentacular cirri of segment 2 and 3. White dots present throughout the mediodorsal part of the body. Other parts of the body with dark olive green pigmentation ( Fig. 6 A).

Habitat. Cliffs and unconsolidated sediments at Mel Island (Paraná) and the continental shelf in the Campos Basin, Brazil.

Geographical distribution. Atlantic Ocean, Brazil, Mel Island and the continental shelf of Campos Basin, Brazil.

Etymology. The name of this species is derived from the Latin words draco (dragon) and dermalis (dermal), meaning dragon skin. There is a certain similarity between the dorsal cirri of living individuals and the scales on the dorsal region of mythical Japanese dragons.

Remarks. All the previous Brazilian records ( Duarte & Nalesso 1996; Duarte 1980; Morgado & Amaral 1984; Nogueira 2000; Amaral et al. 2006 –12) of Eumida sanguinea (Öersted, 1843) , which was originally described from the North Atlantic Ocean ( Denmark), should actually be referred to Eumida dracodermica sp. nov. The two species differ in the size of the prostomium, the distribution of micropapillae on the proboscis, and the shape of the dorsal cirri. In E. sanguinea the prostomium is almost as long as wide, the proboscis has irregularly distributed micropapillae and the dorsal cirri are cordiform, whereas in E. dracodermica sp. nov. the prostomium is clearly longer than wide, the proboscis has six rows of tubercles with micropapillae regularly distributed, and the dorsal cirri of anterior and median segments are cordiform, almost lanceolate on posterior segments. They share the presence of two longitudinal rows of micropapillae on each papilla in the terminal ring of the proboscis. E. dracodermica sp. nov. shares the presence of cordiform dorsal cirri on the median part of the body with Eumida longicirrata Hartmann-Schroder, 1975 (known from the NE Atlantic Ocean, Iberian Basin). It also resembles this species in having supracicular prechaetal lobes that are twice as large as the subacicular lobes, but they differ in the characters of the proboscis, which is smooth in E. longicirrata and possesses tubercles with micropapillae in E. dracodermica sp. nov. E. dracodermica sp. nov. shares the presence of a cordiform prostomium and median dorsal cirri with Eumida longicornuta (Moore, 1906) known from the Northern Pacific Ocean and Eumida minuta (Grube, 1880) , known from Ilha de Santa Catarina, in southern Brazil (previously Desterro Island, Santa Catarina, Brazil). However, E. dracodermica clearly differs from them in the shape of the dorsal cirri, which are symmetrical in anterior and median segments and lanceolate in posterior segments.

Figures

FIGURE 6. Eumida dracodermica sp. nov. A—Overview of the holotype; B—Prostomium, dorsal view, base of tentacular cirri with white pigmentation; C—Distal part of proboscis; D, E—Papillae on terminal ring of proboscis with micropapillae. Scales: A = 2.0 mm; B = 0.7 mm; C = 0.09 mm; D = 0.05 mm; E = 0.1 mm.

FIGURE 7. Eumida dracodermica sp. nov. Anterior view of parapodium of the holotype. A—Parapodium 10; B—Parapodium 45; C—Parapodium 90. Scales: A – C = 0.2 mm.

FIGURE 8. Eumida dracodermica sp. nov. A – C—Dorsal view of compound spinigerous chaetae. Scales: A = 0.01 mm; B = 0.005 mm; C = 0.004 mm.

FIGURE 9. Eumida dracodermica sp. nov. A—Pygidial cirri of a juvenile; B—Regenerating pygidial cirri; C—Pygidial cirri of the holotype. Scales: A – B = 0.3 mm; C = 0.6 mm.