Salvatoria rhopalophora ( Ehlers, 1897 ) Soto & Martín, 2017

Soto, Eulogio H. & Martín, Guillermo San, 2017, Exogoninae (Annelida: Syllidae) from Chilean Patagonia, Zootaxa 4353 (3), pp. 521-539 : 534-537

Salvatoria rhopalophora ( Ehlers, 1897) n. comb.

Figures 8 , 9 , 10

Grubea rhopalophora Ehlers, 1897: 53 , pl. 3, figs. 66–70. Wesenberg-Lund 1962: 65. Brania rhopalophora Hartman 1964: 79 , pl. 25, fig. 1.

Material examined. Station 41 (60), station 55 (3) (LBUV) and station 36 (13 specimens plus 2 specimens for SEM) (MNCN 16.01/17770).

Description. Body small, largest specimen a mature male with natatory chaetae, 2.8 mm long, 0.1 mm wide, for about 31 chaetigers. Prostomium ovate, wider than long, with four thick eyes in trapezoidal arrangement and two anterior eyespots. Antennae spindle-shaped ( Fig. 8A , 9A–C ), subdistally inflated, ending in short tip; shorter than combined lengths of prostomium and palps; median antenna longer than lateral antennae, inserted on line between posterior eyes ( Fig. 8A ); lateral antennae inserted in front of eyes ( Fig. 8A ). Palps similar in length to prostomium or shorter, fused dorsally by a membrane, with small distal notch ( Figs. 8A , 9A–C ). Peristomium shorter than subsequent segments; tentacular cirri similar to antennae but more elongate, dorsal pair similar in length to lateral antennae, ventral pair shorter. Dorsal cirri spindle-shaped, present on all chaetigers, all similar in length or with slight variations in length, except those of chaetiger 1, slightly longer than subsequent ones ( Figs. 8A , 9A–C ). Compound chaetae with bidentate blades, both teeth similar, provided with moderately long, distally directed, thin spines basally, shorter and straight as more distal on margin ( Figs. 8C , 9D–F ); spines longer in dorsalmost chaetae. Anterior parapodia each with about 9–11 compound chaetae; posteriorly number of compound chaetae declines progressively to 5–6 on posterior parapodia, provided with shorter blades, less marked dorsoventral gradation in length of blades. In mid-body, blades of most dorsal compound chaetae 36 mm above, 17 mm below. Dorsal simple chaetae from mid-body, unidentate or minutely bidentate ( Figs. 8B , 9A, B ), with minute subdistal marginal spines. Ventral simple chaetae on most posterior parapodia of some specimens, sigmoid, bidentate, similar to dorsal ones ( Figs. 8E , 10C ). Anterior parapodia each with two aciculae, one straight and another one acuminte; solitary acicula in mid-body and posterior parapodia, acuminate ( Fig. 8D ). Pharynx through about 3–4 segments; pharyngeal tooth small, rhomboidal to ovate, located near anterior margin, but distinct posteriorly, without papillae on opening ( Fig. 8A ). Proventricle similar in length to pharynx, through about three segments, with 18–20 muscle cell rows. Pygidium small, with two anal cirri, similar to dorsal cirri but slightly longer.

Remarks. Salvatoria rhopalophora n. comb. Is similar to S. clavata ( Claparède, 1863) , a common species in NE Atlantic and Mediterranean, which is widely reported and shows great variability and S. koorineclavata San Martín, 2005 from Australia and China. These species have similar compound chaetae with bidentate blades and short spines on the margin. A revision of this group worldwide, using molecular methodology or a detailed comparative morphological study, would be necessary to segregate and delimitate species. However, S. rhopalophora n. comb. seems to have shorter and thicker antennae than the other two species, and with a shorter pharynx and proventricle. Salvatoria clavata also has the pharyngeal tooth farther back than S. koorineclavata and S. rhopalophora .

Distribution. Sub-Antarctic Islands. New to Chile. Chilean Patagonia: from Concepción channel to Magellan Strait (50°16 ʹ S–54°57 ʹ S).

Habitat. Sediments and algae. Intertidal to shallow subtidal (30 m depth). Inside tubes of Chaetopterus cf. variopedatus in fjords and channels from Patagonia. Salinity: from 30.2 to 35 PSU, temperature: from 8.7 to 8.9°C. From Macrocystis pyrifera kelp holdfast Salinity: 16 temperature: 5.7°C.

Figures

FIGURE 8. Salvatoria rhopalophora (Ehlers, 1897) n. comb. MNCN 16.01/17770. A, anterior end, dorsal view. B, dorsal simple chaeta, midbody parapodium.C, compound chaetae, midbody parapodium.D, acicula, midbody parpaodium.E, ventral simple chaeta, posterior parapodium. Scale bars. A: 0.1 mm.B–F:20 µm.

FIGURE 10. Salvatoria rhopalophora (Ehlers, 1897) n. comb. SEM.A, B, dorsal simple chaeta.C, ventral simple chaeta.

FIGURE9. Salvatoriarhopalophora (Ehlers, 1897)n.comb.SEM.A, completespecimen, dorsalview.B, anteriorend, dorsal view.C, female carrying eggs, dorsal view. D–F, compound chaetae.