Aspidisca hexeris Quennerstedt, 1869
publication ID |
https://doi.org/ 10.12651/JSR.2023.12.1.090 |
persistent identifier |
https://treatment.plazi.org/id/C57F879B-8B76-FF8F-FCFA-FD24FDD7FA99 |
treatment provided by |
Felipe |
scientific name |
Aspidisca hexeris Quennerstedt, 1869 |
status |
|
2. Aspidisca hexeris Quennerstedt, 1869 View in CoL ( Fig. 2 View Fig )
Material examined. Brackish water (salinity 12.8‰, temperature 33.5℃) collected from Yongdumbeong , Sinyang-ri , Chuja-myeon, Jeju-si, Jeju-do, Korea (33°57 ʹ 38.90 ʺ N, 126°17 ʹ 7.30 ʺ E) on August 19, 2021 GoogleMaps .
Diagnosis. Size 32 - 33 × 26 - 29 μm in vivo and 23 - 30 × 21 - 25 μm after protargol impregnation (n = 7); body shape broadly oval; cortex rigid with a single peristomial spur and 4 projections along left margin ( Fig. 2A - C View Fig ); AZM1 about 7 μm long with 7 - 8 membranelles, AZM2 about 10 μm long after protargol impregnation and with 10 - 12 membranelles; 7 frontoventral cirri in “ polystyla -arrangement”; 5 transverse cirri, each transverse cirrus not separated except the leftmost one, which splits into 2 parts; 4 dorsal kineties with 8 - 9, 8 - 10, 8 - 12, 9 - 10 dikinetids in dorsal kineties 1 - 4, respectively; cytoplasm colorless; 1 macronucleus horseshoe-shaped, micronucleus not observed ( Fig. 2D, E View Fig ).
Distribution. China, South Korea.
Remarks. The Korean population of Aspidisca hexeris is similar to the Chinese population in all features except the body size (23 - 30 × 21 - 25 μm vs. 34 - 43 × 25 - 36 μm after protargol impregnation) ( Jiang et al., 2013). Aspidisca hexeris is unique among the genus Aspidisca in having one conspicuous peristomial spur and four small projections along the left margin. Although Wu and Curds (1979) mentioned that the number of projections is highly variable among populations and Jiang et al. (2013) argued that the number of projections is an intraspecific difference, nonetheless, all specimens observed in this study have invariably four projections. Considering the presence of a peristomial spur and the “ polystyla -arrangement” of frontoventral cirri, A. leptaspis and A. magna Kahl, 1932 are very similar to A. hexeris . However, A. leptaspis has eight (vs. 7) frontoventral cirri and has more membranelles in the AZM2 (14 - 21 vs. 10 - 12) ( Li et al., 2010). Aspidisca magna is larger than A. hexeris (50 - 160 × 40 - 115 in vivo vs. 32 - 33 × 26 - 29), has more frontoventral cirri (7 - 9 vs. invariably 7), and also has more membranelles in the AZM2 (15 - 18 vs. 10 - 12) ( Li et al., 2010; Huang et al., 2011; Jiang et al., 2013). Furthermore, both A. dentata and A. hexeris possess the peristomial spur, however, they differ mainly in the absence (vs. presence) of the projections along the left margin.
Voucher slides. Three slides with protargol-impregnat- ed specimens were deposited at the National Marine Biodiversity Institute of Korean (MABIK PR00044187, PR00044188, and PR00044189).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
Kingdom |
|
Phylum |
|
Class |
|
Order |
|
Family |
|
Genus |