Euglesa khurbaensis Zatravkin, 1987

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 : 323

Euglesa khurbaensis Zatravkin, 1987

( Fig. 9B ) Euglesa khurbaensis Zatravkin, 1987: 49–51 , text fig. (I).

Type locality: Russia, Khabarovsk Territory, Verkhnebureinsky District, first floodland lake of the Bureya River near Chekunda settlement .

Type series: The type series includes the holotype and 28 paratypes in ZIN, nos 1, 3–5 in the systematic catalogue .

Material examined: Russia, Primorsky Territory, Nadezhdinsky District, near Utinoe Lake , IX.2020, Aksenova, Bespalaya, Kropotin, Travina & Vinarski leg., 30 specimens (lot nos RMBH MSph-707, MSph-708, MSph-709, MSph-710) .

Description: Shell medium sized (length ± SD 4.41 ± 0.4 mm), round-oval in shape ( Fig. 9B ). The beaks are rounded, slightly prominent, offset to the posterior edge of the valves ( Fig. 9B ). The cardinal tooth of the right valve is curved, thin, the posterior end is branched. The outer cardinal tooth of the left valve is slightly curved and inclined towards the inner tooth. The inner cardinal tooth of the left valve is curved ( Fig. 10B ).

Distribution: Khabarovsk Territory (Russian Far East).

Comment: The 16S and 28S rRNA sequences of this species appeared to be unique, without analogues in GenBank. We analysed the original descriptions and type specimens of some nominal species from nearby localities: Euglesa khurbaensis Zatravkin, 1987 , Euglesa koltschemensis Zatravkin, 1987 , and Euglesa kruglovi Zatravkin, 1987 (Supporting Information, Fig. S1F, G, H ). Graf and Cummings (2023) considered E. kruglovi as a synonym of E. khurbaensis . The original morphological description of E. khurbaensis published by Zatravkin 1987 (Supporting Information, Fig. S1F ) corresponds well to the morphological features of our specimens from the Primorsky Territory. Hence, we assume that this species can be classified as E. khurbaensis . The taxonomic status of E. koltschemensis needs to be clarified.

Figures

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

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.