Lecane nana (Murray, 1913)

Min, Hee-Min Yang and Gi-Sik, 2021, New records of three lecanid rotifers (Rotifera: Monogononta: Lecanidae) from Korea, Journal of Species Research 10 (3), pp. 262-266 : 265

3. Lecane nana (Murray, 1913) ( Fig. 2D- F )

Cathypna nana Murray, 1913b, p. 353 . Lecane nana : Harring, 1914, p. 536; Harring & Myers,

1926, p. 375; Kutikova, 1970, p. 460; Koste & Shiel,

1990, p. 27; Segers, 1995, p. 42, 44.

Material examined. Reservoir in Yeongdeok-ri , Bukmyeon , Yeongwol-gun, Gangwon-do, Korea, 37°17 ʹ 05.6 ʺ N, 128°26 ʹ 09.9 ʺ E. Collected by Hee-Min Yang on 20 Jun 2019 (NNIBRIV50293) .

Description. Lorica stiff. Anterior margin straight or slightly convex. Antero-lateral corner angulate. Width of ventral plate convex in middle and getting narrow toward the posterior end. Dorsal plate anteriorly as wide as ventral plate, wider in the middle. Length of dorsal plate shorter than ventral plate. Dorsal lorica 60.0 - 62.5 μm in length, 58.0 - 60.0 μm in width. Ventral lorica 65.0 - 70.0 μm in length, 54.5 - 56.5 μm in width. Incomplete longitudinal and transverse fold in ventral plate. Prepedal folds narrow with median projection posteriorly. Foot pseudosegment squircle shaped, with bulge in middle and slightly protruded from foot plate. Toes completely separated. Tip of toes sharp and curved outwards. Toe 26 μm in length ( Fig. 2D, E ). Trophi malleate. Fulcrum short and stubbed. Unci square shaped with two big teeth. Manubria thick, rapidly tapering to the end. Tip of manubria with distinctly curved end ( Fig. 2F ).

Distribution. Cosmopolitan.

Remarks. Lecane nana is a cosmopolitan species that has previously been recorded in a number of Asian counties: Cambodia ( Meas and Sanoamuang, 2010), China ( Huang et al., 2017), India ( Sharma, 1978), Japan ( Sudzuki, 1964), Mongolia ( Jersabek, 2010), Thailand ( Sanoamuang et al., 1995), and Vietnam ( Zhdanova, 2011). It can be distinguished from other lecanid species by the following characteristics: (1) two separated toes with a curved terminal end, (2) an anterior margin of the dorsal and ventral lorica that is coincident and straight, and (3) incomplete transverse and longitudinal folds on the ventral plate. This species is most similar to L. tryphema Harring & Myers, 1926 , but can be distinguished from the former by its toe tips curved outwards.

Figures

Fig. 2.A-C. Lecane furcata. A. Line drawing of preserved specimen. B. photograph of preserved specimen. C. trophi. D-F.Lecane nana. D. Line drawing of preserved specimen. E. photograph of preserved specimen. F. trophi. Scale bars:A, B, D, E=50μm, C, F=10μm.