Cirrophorus brevicirratus Strelzov 1973

• Main Author: Sikorski, Andrey
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2017
• Subjects: Biodiversity; Taxonomy; Animalia; Annelida; Polychaeta; Paraonidae; Cirrophorus; Cirrophorus brevicirratus; Antarc*; Antarctic; Antarctic Peninsula
• Online Access: https://doi.org/10.5281/zenodo.6050869; http://treatment.plazi.org/id/5B0CE503946CFB4F84824FADFEC97CAF

Cirrophorus brevicirratus Strelzov, 1973 (Fig. 3) Cirrophorus brevicirratus Strelzov, 1973: 124, fig. 53A–J. Material examined. 4020 Askøy 2007 KL1–4; 10.07.2007; 60.4068°N–5.2286°E; 14 m; one specimen. 6244 Veslefrikk VFR 03; 60.7760°N–2.9100°E; 170 m; 27.05.2013; five specimens. Additional material. BENTART–AP21, Antarctic Peninsula; 64.9000°S–63.0185°W; 107 m; 23.02.2003; three specimens. Description. All specimens incomplete, largest one 10 mm long, 0.1 mm wide for 80 chaetigers. Body slender, dorsoventrally flattened in pre- and branchial regions, cylindrical in postbranchial region. Prostomium triangular, slightly wider than long (Fig. 3A); minute median antenna in largest specimens only (Strelzov 1973), lacking in the examined specimens from Norway; apical sensory organ absent; pair of nuchal organs as slightly oblique nuchal slits (Fig. 3A). Notopodial postchaetal lobes of chaetiger 1 as short, rounded tubercles (Fig. 3A); slightly longer and piriform on remaining prebranchial chaetigers and in branchial region; short and digitiform in postbranchial region (Fig. 3C). Branchiae from chaetiger 4, 9 pairs, bearing ciliation on their inner edge, digitiform and distally rounded, up to four times as long as wide (Fig. 3A, B). Noto- and neurochaetae as geniculate bilimbated capillaries in prebranchial and branchial regions (Fig. 3A, B); in postbranchial region as thin, straight capillaries, clearly less numerous (Fig. 3C); from chaetiger 4–8 bearing 1–2 forked notopodial chaetae with tines similar in thickness but differing in length, with inner edges bearing short spinulation (Fig. 3D); modified neurochaetae absent. Remarks. Our specimens can be accurately referred to C. brevicirratus by having forked modified notochaetae, up to 15 pairs of branchiae and very short notopodial postchaetal lobes in the branchial region. Although typical of genus Cirrophorus , in this species the median antenna is very small and only appreciable in largest individuals, which are 0.4 mm wide and possess more than 90 chaetigers ...