Chrysosphaerella grandibasa (Balonov) Kapustin, 2024

Kapustin, Dmitry A., 2024, An updated checklist of the silica-scaled chrysophytes from Russia, Phytotaxa 669 (3), pp. 165-193 : 170-171

44. Chrysosphaerella grandibasa (Balonov) Kapustin , comb. et stat. nov.

Basionym: Chrysosphaerella coronacircumspina var. grandibasa Balonov. 1979 . Trudy Inst. Biol. Vnutr. Vod AN SSSR 42: 13, fig. 4,

pl. 8e, pl. 9а, г, д.

Lectotype (designated here): [icon in] Trudy Inst. Biol. Vnutr. Vod AN SSSR 42 : pl. 9a. 1979.

Registration: http://phycobank.org/104965

Republic of Karelia, Vologda Region ( Balonov 1979); Leningrad Region ( Safronova 2012, Safronova & Voloshko 2013).

Remark. Balonov (1979) described a new variety, C. coronacircumspina var. grandibasa , from the Lake Munozero in Karelia. This taxon differs from the type variety in having shorter spines with a wider base-plate and more circular plate-scales ( Balonov 1979). Later authors ( Safronova 2012, Safronova & Voloshko 2013, Voloshko 2016, Snitko et al. 2019) emphasized the presence of a large pore at the spine base, although such pore is not a unique diagnostic feature of this taxon and many other Chrysosphaerella species (e.g., C. longispina , C. brevispina , C. enigmata and C. septentrionalis ) have it.

In our opinion, there are enough morphological differences between C. coronacircumspina var. grandibasa and C. coronacircumspina var. coronacircumspina to raise the former taxon to a species rank as C. grandibasa . The records of Chrysosphaerella grandibasa outside the type locality are doubtful and probably belong to C. coronacircumspina .