Parapionosyllis Fauvel, 1923 : 289

Riera, Rodrigo & Brito, Jorge Núñez And María Del Carmen, 2006, Parapionosyllis (Polychaeta: Syllidae: Exogoninae) from Tenerife (Canary Islands, Spain) with description of a new species and new records, Zootaxa 1110, pp. 17-26 : 19-21

Parapionosyllis Fauvel, 1923: 289 .

Parapionosyllis minuta ( Pierantoni, 1903)

Pionosyllis minuta Pierantoni, 1903: 239 , fig. 5.

Parapionosyllis minuta . — Fauvel, 1923: 292, fig. 111 f; San Martín, Viéitez & Campoy, 1981: 68, fig. 8; Campoy, 1982: 263, fig. 17; San Martín, 1984: 198, fig. 44; San Martín, 2003: 288, figs. 158–159.

Material examined.—Los Abrigos beach (Tenerife), Lat. N. 28º08´58´´ Long. W. 16º42´54´´, 3 m depth, 1 specimen, June 2000, coll. R. Riera.

Ecology.—This species was recorded in medium grained sands with an organic matter of 1.54% and 6.84% of carbonates. The species has been recorded from a variety of habitats and reaches its highest abundances in sandy substrates, green algae ( Caulerpa spp.) and seagrass meadows ( Zostera and Posidonia ) ( Viéitez, 1976).

Distribution.—East Atlantic and Mediterranean ( San Martín, 2003). This is the first record of this species from the Canary Islands.

Parapionosyllis macaronesiensis Brito, Núñez & San Martín, 2000

Parapionosyllis macaronesiensis Brito, Núñez & San Martín 2000: 1147 , fig. 1. Parapionosyllis sp.— Núñez, Pascual, Delgado & San Martín 1995: 6.

Material examined.—Los Abrigos beach (Tenerife), 3 m depth, 1 specimen, March 2001, coll. R. Riera.

Ecology. —This species was recorded in medium grained sands with an organic content. of 0.91% and 6.32% of carbonates. It is a strictly interstitial species of sandy subtidal bottoms ( Brito, 2002). In Madeira it was collected in coarse grained sands with shell remains, rich in carbonates ( Núñez et al., 1995).

Distribution. —East Atlantic: Central Macaronesian Region (Madeira, Selvagens Islands and Canary Islands).

Parapionosyllis abriguensis sp. nov. ( Figure 1 , Table 1 )

Type locality. —Los Abrigos beach (Tenerife, Canary Islands)

Type material. — Holotype (microscopic slide) (TFMCBM AN/000222) Los Abrigos beach (Tenerife), Lat. 28º08´30N Long. 16º26´10´´W, 3 m depth, July 2000, coll. R. Riera. Paratypes, three specimens (microscopic slide): (DBAULL PO/TA12S11; /TA4S55; / TA3S55), Los Abrigos beach (Tenerife), same coordinates; 3 m depth, August 2000, coll. R. Riera.

Description. —Body long, tapering towards both ends, without any pigmentation. Body 0.8–1.6 mm long, and 61–100 m wide at proventricle level. Prostomium semicircular to ovate, slightly wider than long, apparently without eyes. Antennae skittleshaped, median antenna slightly longer (77 m) than lateral ones (72–75 m). Lateral antennae inserted near of half margin of the prostomium, median antenna inserted behind on the posterior margin ( Fig. 1A ). Palps broad, similar in length to prostomium, fused along basal half, leaving a mid­dorsal seam and frontal scar. Single pair of tentacular cirri, originating laterally, more or less similar in length (71 µm) and width to lateral antennae ( Fig. 1A ). Peristomium dorsally reduced. Dorsal cirri on all chaetigers, slightly shorter (43–68 m) than lateral antennae and with granular material distally. Parapodial lobe triangular­shaped, with a ventral cirri digitiform (23–32 m) similar in length to parapodial lobe ( Fig. 1C ). Apparently lacking subdermal dorsal glands. Anterior parapodia each with one long­bladed compound chaeta and up to five falcigers with shorter blades; progressively, number of falcigers decreasing in median and posterior parapodia ( Fig. 1E ). Long blades unidentate, with tips rounded and uniform fine serration along one margin. Dorsalmost falcigers blades about 31 m on most anterior parapodia, 39 m in midbody and 40 m posteriorly. Remaining shorter falcigers with dorso­ventral gradation in length of blades, in midbody 14 m above, 9 m below. Solitary dorsal simple chaeta from anterior parapodia, unidentate, provided with spinulated serrations distally, without thick spines ( Fig. 1D ). Posterior parapodia also with a solitary ventral simple chaeta, sigmoid and bidentate ( Fig. 1F ). Solitary thick acicula in each parapodium, distally rounded hollow at the tip ( Fig. 1G ). Pharynx wide, extending through about three segments, provided with a conspicuous, conical middorsal tooth on the anterior rim. Proventricle shorter than pharynx, extending through about three segments, and with about 16–18 rows of muscle cells. Pygidium with one pair of long, slender anal cirri (125 m) and one caudal appendix (18 m) ( Fig. 1B ).

Remarks.— Parapionosyllis abriguensis sp. nov. is characterized by having a unidentate dorsal simple chaeta with spinulated serrations without any thick spines, bidentate ventral simple chaeta, marked dorso­ventral gradation and by the length of the falcigerous blades and smooth dorsal cirri. Parapionosyllis floridana San Martín, 1991 is the species most similar to P. abriguensis , both are the two only species of this genus having bidentate simple ventral chaetae and lacking eyes, but it differs in having pseudoarticulated dorsal cirri and a less marked dorso­ventral gradation in the length of the falcigerous blades (10–33 m in P. floridana and 9–39 m in P. abriguensis ). Ecology. —This species was recorded in fine and medium sands. The organic matter content ranged from 0.77% to 0.85% and carbonates from 5.13% to 9.57%.

Etymology. —The derivatio nominis refers to the type locality, Los Abrigos beach. Distribution. —Tenerife, Canary Islands.

Figures

FIGURE 1 A. Parapionosyllis abriguensis sp. nov. Anterior segments, dorsal view. Scale = 75 m.