Pherecardites parva Horst 1912

• Main Authors: Bleeker, Joke, Harris, Leslie, Ten Hove, Harry A., Salazar-Vallejo, Sergio I.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2023
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Amphinomida; Amphinomidae; Pherecardites; Pherecardites parva; Median Ridge; Antarc*; Antarctica
• Online Access: https://zenodo.org/record/8183869; https://doi.org/10.5281/zenodo.8183869

Pherecardites parva Horst, 1912 (Fig. 1) Pherecardites parva Horst, 1912: 33, pl. 9, figs 17-19. — Bleeker & van der Spoel 1992: 152 (lectotype designation). TYPE MATERIAL. — Indonesia. Lectotype • 1 specimen; RV Siboga; Sta. 122; 01°58.5’N, 125°0.5’E; 1264- 1165 m depth; 17.VII.1899; ZMA V.Pol 1072.1.g. PARALECTOTYPES. — Indonesia • 1 specimen; RV Siboga; Sta. 139; 00°11’S, 127°25’E; 397 m depth; 4.VIII.1899; ZMA V.Pol. 1072.2 • 1 specimen; RV Siboga; Sta. 173; 03°27’S, 131°0.5’E; 567 m depth; 28.VIII.1889; ZMA V.Pol. 1072.3. DISTRIBUTION. — Indonesia, in sediments at 397-1264 m water depth. OBSERVATIONS Lectotype (ZMA V.Pol 1072.1) colorless, without posterior region, bent ventrally, breaking in two (Fig. 1A). Body about 10 mm long, 2.5 mm wide, 30 chaetigers. Prostomium (Fig. 1B) slightly eroded, left lateral antenna lost, right one present, inserted close to median antennal base. Median antenna thick, bent laterally, without tip. 2/3 as long as caruncle. Palps lost. Eyes not seen. Caruncle straight, with a median ridge and 4 digitate lateral lobes, directed posteriorly. Branchiae from chaetiger 1 lost; chaetiger 2 with 2 digitate filaments, in anterior chaetigers branchiae with about 5 filaments. Pharynx not exposed (Fig. 1C). Posterior end lost; pygidial features unknown. REMARKS Horst (1912: 33) did not see eyes in his specimens (longest one slightly more than 7 mm in length) but noted some black spots. Kudenov (1993: 96-97) noted in P. antarctica (Hartman, 1967) n. comb., specimens of different size (8-12 mm long) had eyes well developed and their pigments were retained despite being in ethanol for over 30 years, whereas in P. parva eyes were not seen. Horst (1912: 33) characterized the caruncle in the diagnosis for Pherecardites, and in the description of P. parva, as having a median ridge and lateral lamellae, directed posteriorly, extended along three segments. Branchiae were noted as starting in chaetiger 1 but the number of filaments was not given. Likewise, the presence of branchiae along ...