Ceriodaphnia nikolaii Garibian & Andreeva & Kotov 2023, sp. nov.

• Main Authors: Garibian, Petr G., Andreeva, Lena V., Kotov, Alexey A.
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2023
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Branchiopoda; Diplostraca; Daphnidae; Ceriodaphnia; Ceriodaphnia nikolaii; Sakha; Yakutsk; Andreeva; lena river; Republic of Sakha; Yakutia
• Online Access: https://doi.org/10.5281/zenodo.7930782; http://treatment.plazi.org/id/86578788CB6CFFFDFF64FF026035F794

Ceriodaphnia nikolaii sp. nov. (Figs. 9–16) Etymology. The taxon is named after our teacher, Prof. Nikolai N. Smirnov, who initiated great progress in the studies of cladocerans in Eurasia and in the world and collected the type series. Type locality. An un-named oxbow of the Lena River, City Yakutsk, Republic of Sakha (Yakutia), Russia (62.0˚N, 129.8˚E). Type material. Holotype. A parthenogenetic female, MGU Ml 266 at the Collection of Zoological Museum of M. V. Lomonosov Moscow State University, Moscow, Russia. Allotype. An adult male, MGU Ml 267. Paratypes. Ten parthenogenetic females, six ephippial female and seven adult males, MGU Ml 268. Several parthenogenetic, ephippial females and males, AAK 1999-045. Adult parthenogenetic female. General (Figs. 9b,c,e,f). Body subovoid in lateral view, with maximum height in middle of valves. Dorsal margin interrupted by a depression in posterior head portion. Dorsal and ventral portion ovoid, poster-dorsal angle present, with small caudal spine. Postero-dorsal angle well-developed, sometimes represented by a short caudal spine, valve margin from the former to anterior margin uniformly rounded. In dorsal view, body subovoid and elongated. Head (Figs. 10a–g) small, ovoid, without rostrum, with a strong depression in posterior head half; small dorsal head pore in this depression. Dorsal head pore round; supraocular dome surround relatively big compound eye; ocellus minute. Labrum (Fig. 10g) quadrangular, with a wide fleshy main body and large setulated labral plate. In dorsal view, fornices from rounded to slightly projected. Valve large and ovoid (Figs. 11a–f); ventral portion with long setae at inner margin (Figs. 11a–b); postero-ventral portion with a row of short setae, short series of setules between them (Fig. 11c); two relatively long setae in dorsal most portion (Fig. 11d–f). Abdomen (Figs. 12b, h, i) short consisting of four segments, first segment having a long abdominal projection. Postabdomen (Figs. 12a–i) elongated, tapering distally. Ventral portion ...