Lecane perplexa ( Ahlstrom, 1938 )

Min, Hee-Min Yang and Gi-Sik, 2023, New record of three monogononts (Rotifera: Monogononta) from islands of Korea, Journal of Species Research 12 (2), pp. 174-179 : 175-176

Lecane perplexa ( Ahlstrom, 1938) ( Figs. 1 , 2 ) Ḥê월형HȐḢḦÊḝ (ṵḑ)

Monostyla perplexa Ahlstrom, 1938 , pp. 101, 102.

Material examined. Reservoir in Goya-ri , Jindo-gun (34°26′31.8″N, 126°10′30.6″E), 05 May 2021, Hee-Min Yang. Voucher Number: HNIBRIV363, HNIBRIV546 .

Diagnosis. Loricate. Anterior margin of dorsal lorica straight, ventral lorica slightly concave. Width of dorsal lorica narrower than ventral lorica in the front, and slightly wider than ventral lorica in the middle. Dorsal lorica 65.0 - 70.0 μm in length. Ventral lorica 70.0 - 85.0 μm. Width of lorica 55.0 - 68.0 μm. Transverse fold of ventral lorica incomplete. Foot plate wide and foot pseudosegment squircle. Single toe with pseudoclaws and accessory claws. Toe length 35.0 μm. Malleate type trophi. Alula of right ramus containing a hook-shaped projection. Fulcrum short, and inverted T-shaped. Each uncus with two large teeth. Posterior end of manubrium curved inwards.

A

Distribution. Cosmopolitan.

Remarks. The identification of L. perplexa based on morphology is difficult because of its similarity to L. lunaris (Ehrenberg, 1832) . However, despite the similarities, the two species do have a few characteristics that set them apart. Compared to L. lunaris , L. perplexa is characterized by a lorica with a flat or slightly concave anterior margin, a smaller body, and a relatively short toe in proportion to its lorica size. Additionally, L. perplexa tends to have a shorter foot pseudosegment than L. lunaris . Lecane perplexa is also confused with L. rhopalura (Harring & Myers, 1926) and L. scutata (Harring & Myers, 1926) . However, L. perplexa can be distinguished from L. rhopalura by the angulated shape of its antero-lateral corners and the absence of bulging in the toes, and it differs from L. scutata by its larger body size and deeper lateral sulci.

Molecular data. A partial COI sequence (759 bp) was obtained from one specimen (GenBank accession number: OQ445411).

Figures

Fig. 1. SEM images of Lecane perplexa (Ahlstrom, 1938). A. dorsal view. B. ventral view. C. trophi, dorsal view. Scale bars=A, B: 50μm, C: 10μm.

Fig. 2. SEM image of trophi of Lecane perplexa (Ahlstrom, 1938). Incus, ventral view. Scale bar=10μm.