Limnias lenis, Meksuwan, Phuripong, Jaturapruek, Rapeepan & Maiphae, Supiyanit, 2018

Meksuwan, Phuripong, Jaturapruek, Rapeepan & Maiphae, Supiyanit, 2018, Two new species of genus Limnias from Thailand, with keys to congeners (Rotifera, Gnesiotrocha), ZooKeys 787, pp. 1-15 : 3-4

Limnias lenis sp. n.

Material examined.

Holotype. A contracted female in a mounted slide deposited in Princess Maha Chakri Sirindhorn Natural History Museum (PSUNHM), Prince of Songkla University, Songkhla, Thailand: PSUZC-PK5PM4-1. Paratypes. Two females in PSUNHM: PSUZC-PK5PM4-2-3; two females in Zoology Laboratory, Science Program, Faculty of Science and Technology, Phuket Rajabhat University, Phuket, Thailand: PKRU-RF2-1-2. In total, seven specimens were examined.

Type locality.

Jik peat swamp, Phuket Province, Thailand: 8°8.683'N, 98°17.983'E. Size of the peat swamp is about 230 × 140 meters. Individuals of L. lenis sp. n. were found attached to roots of Water hyacinth ( Eichhornia crassipes (C.Mart.) Solms). November 15th, 2015.

Etymology.

The species name is an adjective, derived from the Latin " lenis ", meaning "soft, smooth, gentle" and refers to the smooth surface of its dorsal plate.

Diagnosis.

The species is unique by its corona having a relatively shallow ventral sinus compared to other taxa, and by its smooth dorsal plate, without any projection (Figs 1 A–C, 3 A–C, 7A).

Description.

Tube ringed, proximal part smooth, usually transparent. Trunk slender, tapers into slender foot with short stalk (Figs 1A, 3A). Corona two-lobed, twice as wide as trunk, lobes nearly circular, ventral sinus shallow, dorsal gap large, as wide as trunk or nearly so (Figs 1A, 3B). Two short ventral antennae not extending beyond the corona. Dorsal plate smooth, without any projection. Dorsal antenna aperture situated one-fifth of dorsal plate length from the anterior margin (Figure 7A). Trophi malleoramate, symmetrical. Left and right proximal unci teeth: 3/3, distal teeth: 17/17 (Figure 8A). Rami apophyses equal. Manubria crescent-shaped with three chambers. Corona width: 98-110, corona height: 49-58, depth of ventral sinus: 7-12, width of dorsal gap: 33-38, length of lateral antennae: 9-14 (in µm).

Distribution.

The species is known only from its type locality.