Testudinella emarginula ( Stenroos, 1898 )

Song, Min Ok, 2018, Five new records of monogonont rotifers from Korea, Journal of Species Research 7 (4), pp. 333-339 : 337

5. Testudinella emarginula ( Stenroos, 1898) ( Fig. 5 )

빗̈주름접시윤충 (신칭)

Pterodina emarginula Stenroos, 1898, pp. 168­169 , pl. 2, figs. 31­32; Von Hofsten, 1923, pp. 868­869, fig. 11.

Testudinella incisa emarginula : Koste, Janetzky and Vareschi, 1993, p. 137, figs. 27a­b.

Testudinella emarginula : Carlin, 1939, pp. 32­34, fig. 9a.

Material examined. Five specimens in Gyeongpo wetland area, Gangneung-si, Gangwon-do, 37°47 ʹ 19.9 ʺ N, 128°53 ʹ 49.8 ʺ E, 15 Oct. 2017.

Diagnosis. Lorica dorsoventrally flattened and slightly elliptical. Anterodorsal margin slightly bilobed and with inverted V­shaped fold medially; two parallel oblique folds outside median fold. Anteroventral margin bilobed medially and median lobes protruding beyond anterodorsal margin. Foot opening at posterior part of ventral plate. Cross section boomerang­shaped; convex dorsally and concave ventrally.

Measurement. Lorica length 55.7­119.7 μm. Lorica width 46.4­95.5 μm. Foot opening width 8.6­18.9 μm.

Remarks. Testudinella emarginula is periphytic and epibenthic in stagnant and running freshwater, and in paddy fields, athalassic saline and coastal brackish waters. The Korean specimens were found at Gyeongpo wetland area, which is brackish.

Even though this species is cosmopolitan, it is new to the Korean fauna. In Asia, it has been reported from India ( Sharma, 2014), Laos ( Segers and Sanoamuang, 2007), Pakistan ( Ejaz et al., 2017), and Thailand ( Segers et al., 2004; Chittapun et al., 2007).

Distribution. Cosmopolitan.

Deposition. Deposited in the collection of the Nakdonggang National Institute of Biological Resources, Sangjusi, Gyeongsangbuk­do, Korea (NNIBR2018113IV956, NNIBR2018113IV959, NNIBR2018113IV960).

Figures

Fig. 5. Testudinella emarginula(Stenroos, 1898).A. ventral view; B. dorsal view (Scales:A=25μm; B=50 μm).