Colurella cf. psammophila Segers & Chittapun, 2001

Wei, Nan, Jersabek, Christian D., Xu, Runlin & Yang, Yufeng, 2019, New species and records of Colurella (Rotifera: Lepadellidae) from South China, with a key to Chinese Colurella, Zootaxa 4586 (3), pp. 475-490 : 481-482

Colurella cf. psammophila Segers & Chittapun, 2001

( Fig. 6 )

This species has an elongated lorica with unevenly curved anterior aperture margins in lateral view, shows high similarity with the typical form of Colurella psammophila Segers & Chittapun, 2001 , but differs from the latter by (1) greater lorica length: 91.8 µm vs. 65–81 µm in Thai specimens ( Segers & Chittapun, 2001) and 70.0– 81.5 µm in Chinese specimens (this study); (2) distinctly higher ratio of lorica length/height: 1.87 vs. 1.50–1.68 in Chinese specimens of C. psammophila ; (3) toes slightly longer: 42.2 µm vs. 30–38 µm in Thai specimens ( Segers & Chittapun, 2001) and 33.0– 37.7 µm in Chinese specimens; (4) without median keel in C. cf. psammophila vs. with a conspicuous median keel in C. psammophila .

Besides, the elongated lancet-shaped lorica also shows superficial similarity with Colurella colurus compressa ( Lucks, 1912) . It differs from the latter mostly by (1) the outline of its anterior aperture margin being undulate, not evenly curved, with a shallow concavity in its lower ventral third, whereas, the head aperture margins are smoothly curved in C. colurus compressa ( Lucks, 1912) ; (2) toes spread in C. cf. psammophila , which are usually appressed in C. colurus compressa .

This Colurella only occurred in the mangrove swamp in December 2007 ( Tab. 1 ) with one specimen. More specimens are needed to settle its taxonomic status.

Measurements. Body (N = 1 female): Lorica length 91.8 µm, lorica height 49.0 µm, lorica width 42.7 µm, anterior aperture width 39.1 µm, second foot pseudosegment 6.7 µm, third foot pseudosegment 8.2 µm, toe length 42.2 µm.

Figures

FIGURE 6. Colurella cf. psammophila. A, C. Left lateral view. B, E. Ventral view. D. Dorsal view. Scale bar: A–E: 50 µm.