Euglesa nordenskioldi
Creators: name: Bespalaya, Yulia V.
name: Vinarski, Maxim V.
name: Aksenova, Olga V.
name: Babushkin, Evgeniy S.
name: Gofarov, Mikhail Yu.
name: Kondakov, Alexander V.
name: Konopleva, Ekaterina S.
name: Kropotin, Alexander V.
name: Mabrouki, Youness
name: Ovchankova, Nadezda B.
name: Palatov, Dmitry M.
name: Sokolova, Svetlana E.
name: Shevchenko, Alexander R.
name: Travina, Oksana V.
name: Taybi, Abdelkhaleq F.
name: Soboleva, Alena A.
name: Zubrii, Natalia A.
name: Bolotov, Ivan N.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Bivalvia
Sphaeriida
Sphaeriidae
Euglesa
Euglesa nordenskioldi

description: Euglesa nordenskioldi (Clessin in Westerlund, 1876)
(Fig. 9H)
Pisidium nordenskioldi Westerlund, 1876: 68–69, pl., fig. 20.
Type series: Not traced, probably lost.
Type locality: Russia, Krasnoyarsk Territory (northern part) and Tyumen Region. The syntypes were collected in several localities ["Jenissei, vid Dudino, (lat. 69°15 ʹ), Surgutskoj (lat. 62°50 ʹ), Worogowa Selo (lat. 69°50 ʹ)"; Westerlund 1877: 69].
Material examined: Vashutkiny lakes, VIII.2016, Aksenova, Aksenov, Bespaliy, Sokolova & Shevchenko leg., 94 specimens (lot nos RMBH MSph 184, 263), Vaigach Island, VIII.2010, Aksenova & Bespalaya, leg., 68 specimens; Yugorsky Peninsula, VI.2015, Spitsyn leg., four specimens (lot no. RMBH MSph 86-3).
Description: The shell is medium sized (mean length ± SE 2.9 ± 0.6 mm), round-oval in shape (Fig. 9H), distinctly and regularly striated. The beaks are rounded and prominent, located in the middle of the valves (Fig. 9H). The cardinal tooth of the right valve is slightly curved, with a weaker split at the posterior end. The inner cardinal tooth of the left valve is straight. The outer cardinal tooth of the left valve is thin, slightly curved (Fig. 10E). The lateral teeth are long.
Distribution: Northern European Russia and Siberia.
Comment: The 16S and 28S rRNA sequences of this species have no analogues in GenBank and are more closely related to the E. henslowana group (Fig. 2). We analysed the original descriptions and type specimens of some nominal species of this group from close localities (Supporting Information, Fig. S1A–D), that is, Euglesa nordenskioldi (Clessin in Westerlund, 1877), Euglesa ostroumovi Pirogov & Starobogatov, 1974, Euglesa polonica Anistratenko & Starobogatov, 1990, Euglesa sibirica (Clessin in Westerlund, 1877), and Euglesa suecica (Clessin in Westerlund, 1873). The original morphological description of Pisidium nordenskioldi Clessin published in Westerlund (1876) corresponds well to the morphological features of specimens from our samples. In addition, Korniushin (1996) noted the presence of E. nordenskioldi in the lakes of the Bolshezemelskaya Tundra. According to morphological features, this species can be classified as E. nordenskioldi. At the same time, the type specimens of E. polonica, E. ostroumovi, and E. suecica, studied by us, can be distinguished from E. nordenskioldi by having narrow and prominent beaks, offset to the posterior edge of the valves and with oblique folds (Fig. 9; Supporting Information, Fig. S2A–D). Therefore, we do not have sufficient grounds to synonymize the listed species with E. nordenskioldi.
description: Published as part of Bespalaya, Yulia V., Vinarski, Maxim V., Aksenova, Olga V., Babushkin, Evgeniy S., Gofarov, Mikhail Yu., Kondakov, Alexander V., Konopleva, Ekaterina S., Kropotin, Alexander V., Mabrouki, Youness, Ovchankova, Nadezda B., Palatov, Dmitry M., Sokolova, Svetlana E., Shevchenko, Alexander R., Travina, Oksana V., Taybi, Abdelkhaleq F., Soboleva, Alena A., Zubrii, Natalia A. & Bolotov, Ivan N., 2024, Phylogeny, taxonomy, and biogeography of the Sphaeriinae (Bivalvia: Sphaeriidae), pp. 305-338 in Zoological Journal of the Linnean Society 201 (2) on page 329, DOI: 10.1093/zoolinnean/zlad139, http://zenodo.org/record/13220074