Eurythoe indica ( Schmarda, 1861 )

Salazar-Vallejo, Sergio I., Piotrowski, Christina N., Gustav, Leslie Harris & Paulay, Gustav, 2025, Revision of Pherecardia Horst 1886 (Annelida Amphinomidae), Zoosystema 47 (28), pp. 691-720 : 716-717

Eurythoe indica ( Schmarda, 1861)

( Fig. 17)

Amphinome indica Schmarda, 1861: 142 , pl. 35, fig. 294, 3 text figs.

Amphinome bruguieresi de Quatrefages, 1866: 398-399 . — Baird 1868: 229 (n. syn.).

Eurythoe indica – Baird 1868: 224 (n. comb.). — Bindra 1927: 5-9, Textfigs 1-18, pl. 1, figs 1-4 (syn.).

Eurythoe complanata – Fauvel 1932: 45-46 ( non (Pallas, 1776).

TYPE MATERIAL. — Indian Ocean , Seychelles. Syntypes • 2 specimens; no further data; MNHN TYPE 152 (used for description); MNHN TYPE 153 .

DISTRIBUTION. — Widely distributed in the Indian Ocean.

DESCRIPTION OF TYPE SPECIMENS

Syntype (MNHN TYPE 153) pale, anterior end compressed, without posterior end; caruncle depressed, twice longer than wide; first branchiae with 9-10 filaments; body 110 mm long, 9 mm wide, 94 chaetigers.

Syntype (MNHN TYPE 152) complete, slightly tapered posteriorly. Body wall grayish, with longitudinal or irregular stripes; branchiae and chaetae brownish ( Fig. 17A); some chaetae removed from chaetigers 9 and 25; body 84 mm long, 10 mm wide, 69 chaetigers,

Prostomium transparent, reduced, oval, wider than long. Median antenna slightly shorter than lateral antennae; lateral antennae and palps of similar length. No eyes observed. Caruncle cushion-shaped, smooth, about twice as long as wide, reaching anterior margin of chaetiger 4 ( Fig. 17B). Mouth opens between chaetigers 2-4; superior lips reaching mouth.

Parapodia massive, biramous. Notopodia with dorsal cirri larger than branchiae, with cirrophore half as long as cirrostyle. Neuropodia with ventral cirri short, ventral cirrophore 1/3 as long as cirrostyle.

Branchiae from chaetiger 2, with 2-4 main stems; first branchiae with 5-7 filaments, rapidly increasing in number to about 50-100 filaments in following segments.

Notochaetae of three types ( Fig. 17C): thin spurred or simple capillaries, aciculars, and harpoon chaetae. Neurochaetae mostly furcate, of two different sizes ( Fig. 17D), some simple capillaries or spurred capillaries present especially in anterior chaetigers.

Posterior end slightly damaged ( Fig. 17E); pygidum with anus terminal; anal plate or cirri not observed.

REMARKS

Baird (1868: 229) indicated that Amphinome bruguieresi de Quatrefages, 1866 does not belong in Amphinome Bruguière, 1789 . Yáñez-Rivera & Salazar-Vallejo (2011: 252, Table 1) regarded this species as belonging in Pherecardia , which is the reason for its inclusion and re-assignment herein. The diagnosis indicated the caruncle was elongate and trilobed, which is not the case for typical Amphinome , in which the caruncle is heart-shaped, not trilobed, and made of a single fleshy cushion ( de Quatrefages 1866: 398). The caruncle was described as oval, elongate, and apparently having three lobes on one side, with the other side damaged in the specimen examined. The MNHN types were recently studied, and they have a globular, rather smooth caruncle cover or roof. This species does not belong to Pherecardia , as previously assessed; it rather belongs in Eurythoe Kinberg, 1857 .

Bindra (1927) revised Eurythoe Kinberg, 1857 , and included a key to the then known species. He regarded the genus with a rather wide definition, and consequently numerous species were included in it. Bindra also included a complete characterization and several illustrations of E. indica ( Schmarda, 1861) . Amphinome indica Schmarda, 1861 falls within Eurythoe because its caruncle has a cover or roof which partially obscures the lateral lobes. Additionally, branchial and chaetal patterns resemble Eurythoe Kinberg, 1857 and these character states explain the transfer of A. bruguieresi into Eurythoe . Consequently, E. indica ( Schmarda, 1861) includes A. bruguieresi de Quatrefages, 1866 . The affinities of this species were discussed by Bindra (1927: 5, key).