Anamenia gorgonophila (Kowalesky, 1880)

Cobo, M. Carmen, Farris, William J. & Kocot, Kevin M., 2024, New data on the biodiversity of Solenogastres (Mollusca, Aplacophora) in the Mediterranean Sea: findings from the program “ Our Planet Reviewed ” Corsica 2019 - 2022, Zoosystema 46 (21), pp. 543-576 : 571

Anamenia gorgonophila (Kowalesky, 1880)

Neomenia gorgonophila Kowalevsky, 1880: 190 .

Anamenia gorgonophila – Nierstrasz 1908: 11.

MATERIAL EXAMINED. — Corsica (France) • 1 specimen (used for sclerite preparations, DNA extraction and histology); CORSICABENTHOS 3 ( Table 2 ); 50 m depth; MNHN-IM-2019-18270; GenBank: OR456217; OR458914 (1 microscope slide with sclerites, 44 slides with 5 µm serial sections).

DESCRIPTION

Relatively large animal (30 × 2 mm), without keels or protrusions and with rounded body ends. Brown ( Fig. 3B ) to a lighter yellowish color after fixation ( Fig. 3 B’). Sclerites hollow, acicular, slightly curved and with a wide variety of sizes (125-325 × 18-20 µm). Knife-like scales of the pedal groove (80-90 × 30-40 µm). Foregut very glandular in its anterior region ( Fig. 14C ). Radula with two transverse rows ( Fig. 14D , D’) bearing around seven denticles each. Ventrolateral foregut glands of type B / Imeroherpia type ( Fig. 14D , D’). With abdominal spicules ( Fig. 14E ) and one dorso-terminal sensory organ.

REMARKS

This is a commonly encountered species that is easy to identify based on external aspect and habitus, as it is frequently found coiled on corals. The specimens studied here were found on a colony of Paramuricea sp. ( Anthozoa, Octocorallia) ( Fig. 3B ) at a depth of 50 m, which corresponds to the information available for the species, that can be found epizootic on several species of octocorals in depths between 60 and 900 m (compiled in García-Álvarez et al. 2014). This together with the external appearance (animals up to 20 mm long, brownish, or yellow) and the sclerites (long acicular sclerites, and knife-shaped scales in the pedal groove region) facilitated the identification. The information obtained from the histological sections also corresponds with what was previously described ( Thiele 1902; Pedrouzo et al. 2014; Martínez-Sanjuán et al. 2022). With the specimen included here, we expand its known distribution in the Mediterranean Sea.

Figures

FIG. 3. — Habitus of A, Dondersia festiva Hubrecht, 1888 (photo of the living animal – MNHN-IM-2019-18277); A’, Dondersia festiva (photo of the living animal – MNHN-IM-2019-16169); A’’, detail of the dorsoterminal sensory organs (MNHN-IM-2019-16169); B, Anamenia gorgonophila (Kowalevsky, 1880) (photo of the living animal on Paramuricea sp.): B’, Anamenia gorgonophila (photo of the preserved specimen – MNHN-IM-2019-18270); C, Nematomenia banyulensis (Pruvot, 1890) (photo of the preserved specimen – MNHN-IM-2019-16178); D, Dorymenia vagans (Kowalevsky & Marion,1887) (photo of the preserved specimen – MNHN- IM-2019-18274). Scale bars: 1 mm. Symbols: arrows, dorsoterminal sensory organs; stars, anterior end of the animals.

FIG. 14. — Histological sections of A, Unciherpia hirsuta (MNHN-IM-2019-18279): circumpharyngeal glands and B, Dorymenia vagans (MNHN-IM-2019-18271): copulatory stylets; C-E, Anamenia gorgonophila (MNHN-IM-2019-18270): C, anterior foregut region; D, radular region; D’, detail of the radula, radular sac and ventrolateral foregut glands; E, oblique section of posterior region with abdominal spicules visible on the animal’s right side. Abbreviations: see Material and methods. Scale bars: 100 µm.