Euglesa lindholmi (Starobogatov & Streletzkaja, 1967) Bespalaya & Vinarski & Aksenova & Babushkin & Gofarov & Kondakov & Konopleva & Kropotin & Mabrouki & Ovchankova & Palatov & Sokolova & Shevchenko & Travina & Taybi & Soboleva & Zubrii & Bolotov, 2024

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), Zoological Journal of the Linnean Society 201 (2), pp. 305-338 : 327-328

Euglesa lindholmi (Starobogatov & Streletzkaja, 1967) comb. nov.

( Fig. 9C )

Odhneripisidium lindholmi Starobogatov & Streletzkaja, 1967: 256 , fig. 69.

Type series: The holotype (a separate valve) and three separate valves of paratypes are deposited in ZIN, nos 1 and 2 in the systematic catalogue.

Type locality: Russia, Republic of Yakutia (Sakha), Quaternary deposits on the left bank of the Allaikha River ( Indigirka River Basin ) .

Material examined: North Asia: Gydan Peninsula, VII.2017, Sokolova & Shevchenko leg., Republic of Yakutia , Yana River Basin, VIII.2019, Zubrii leg., Republic of Buryatia, near Vitim Nature Reserve , Dannoe Lake , VIII.2020, Babushkin leg., in total 29 specimens (lot nos RMBH MSph-737, MSph-370, MSph-569/1, MSph-569/2, MSph-572/1) .

Description: The shell is small (mean shell length ± SD 3.15 ± 0.03 mm), round-oval in shape ( Fig. 9C ). The beaks are rounded and prominent, and somewhat offset to the posterior edge of the valves ( Fig. 9C ). The cardinal tooth of the right valve is thickened on the posterior end. The inner cardinal tooth of the left valve is straight. The outer cardinal tooth of the left valve is thickened, shorter than inner cardinal tooth ( Fig. 10C ).

Comments: The 16S and 28S rRNA sequences of this species have no analogues in GenBank and are more closely related to the E. parvula group ( Fig. 2 ). Previously, several species described from the basin of the Indigirka and Kolyma rivers and also from the Kamchatka Peninsula were assigned to the genus Hiberneuglesa Starobogatov in Dolgin, 1983 ( Korniushin 1996, Vinarski and Kantor 2016) with the exception of Euglesa subconventa (Starobogatov & Streletzakaja, 1967) , Pisidium indigircence Starobogatov & Streletzkaja, 1967 , and Euglesa cor (Starobogatov & Streletzkaja, 1967) . Currently, this group is treated as the species E. parvula ( Graf and Cummings 2023; MolluscaBase 2023) with the junior synonyms: Euglesa anjuica Starobogatov & Korniushin, 1989 , Euglesa kolhymensis (Starobogatov & Streletzkaja, 1967) , Euglesa kuiperi (Starobogatov & Streletzkaja, 1967) , Euglesa lindholmi (Starobogatov & Streletzkaja, 1967) , and several species from other regions. Euglesa cor is currently considered as a junior synonym of Euglesa obtusalis (Lamarck, 1818) ( Graf and Cummings 2023; MolluscaBase 2023). These species are still known only from their type specimens (represented by dried shells). We have studied the type specimens and the original descriptions of all of these species (Supporting Information, Fig. S1K, N–Q ). According to morphological features of these type series, and morphological and molecular-genetic analysis of the examined material (see above), we believe that the listed nominal species should be treated as E. lindholmi . The taxonomic status of E. anjuica , E. cor , E. kolhymensis , E. kuiperi , E. subconventa , and Pisidium indigircence needs to be clarified.

Distribution: Siberia.

Figures

Figure 1.Spatial distributionofthe numberofavailable 16S rRNA sequences (A), and species richness of thesubfamily Sphaeriinae (B), in theworld.

Figure 2. The phylogeny of the subfamily Sphaeriinae recovered from ML analysis (W-IQ-TREE) and obtained for the complete dataset of mitochondrial and nuclear sequences (16S rRNA+28S rRNA). Black numbers near nodes are bootstrap support values (BS)/ Bayesian posterior probabilities (BPP). The new taxa are highlighted in red. Subgenera are marked by curly brackets.

Figure 9. Shells of species, re-described in this research: (A) Euglesa khurbaensis (RMBH No. MSph-707, Russia, Primorsky Territory); (B) E. khurbaensis (RMBH No.MSph-707/2, Russia, Primorsky Territory); (C) E.lindholmi (RMBH No. MSph-370, Russia, Gydan Peninsula); (D) E. ljovushkini (RMBH No. MSph-335, Abkhazia); (E) E. ljovushkini (RMBH No. MSph-335/2, Abkhazia); (F) E. hinzi (RMBH No. MSph- 366, Russia, Gydan Peninsula); (G) E. subterranea (RMBH No. MSph-295, Georgia, Imereti); (H) E. nordenskioldi (Russia, Vaygach Island). Photos: O.V. Aksenova.Scale bar: 1 mm.

Figure 10. Morphology and anatomy of re-described species discussed in this research (teeth morphology and shell pores, anatomy of gills and siphons): (A) Euglesa hinzi (RMBH No. MSph-366, Russia, Gydan Peninsula); (B) E. khurbaensis (RMBH No. MSph-707/2, Russia, Primorsky Territory); (C) E.lindholmi (RMBH No.MSph-370, Russia, Gydan Peninsula); (D) E. ljovushkini (RMBH No. MSph-335, Abkhazia); (E) E. nordenskioldi (Russia, Vaygach Island); (F) E.subterranea (RMBH No. MSph-295, Georgia, Imereti). Photos: O.V. Aksenova. Scale bar: 0.5 mm.