Hemirotalia foraminulosa Lei & Li, 2016

Lee, Somin & Lee, Fabrizio Frontalini and Wonchoel, 2023, A report of three newly recorded benthic foraminiferal species from Korea, Journal of Species Research 12 (1), pp. 48-54 : 50-53

2. Hemirotalia foraminulosa Lei & Li, 2016

( Plate 2 , figs. 1-4)

Hemirotalia foraminulosa Lei & Li, 2016, p. 346 , figs. 76, 77.

Material examined. Korea, the South Sea , R / V Saedongbaek (Chonnam National University) cruise st. 4, 33°54′ 55″N, 127°22′46″E, 17 Aug 2022, by Smith-McIntyre grab, collected by Jaehyun Kim. MABIK ID: MABIK PR00044175 - 44178 .

Diagnosis. Test trochospiral, planoconvex to slightly biconvex with lobate, carinate periphery. Ventral side involute, more convex, spiral side flattened to slightly convex, consisting of about three whorls. Chamber size gradually increasing as added, about seven chambers in the final whorl. Chamber shape rounded to trapezoidal on spiral side, and indistinct to semi-triangular on umbilical side. Sutures on umbilical side deeply incised at periphery, length about a quarter of the distance from the umbilicus to the peripheral edge. Umbilicus somewhat pointed, without a plug, covered with folia with scattered multiple pits. Wall calcareous, perforate, except for sutures, carina, and folia. Aperture an indistinct, loop-shaped, interiomarginal slit. Test dimension about 650 μm.

Remarks. There are two species belonging to the genus Hemirotalia Lei & Li, 2016 : H. calvifacta Lei & Li, 2016 , the type species, and H. foraminulosa Lei & Li, 2016 . These two species and the genus Hemirotalia were first described from Chinese waters (i.e., Bohai Sea and Yellow Sea), by Lei and Li (2016). This is the first record of Hemirotalia from Korea. Hemirotalia foraminulosa differs from H. calvifacta , by its scattered pits on the folium of umbilical region, somewhat acutely keeled periphery, and shorter length of sutural incisions on ventral side. Hemirotalia calvifacta has a smooth umbilical region with a single pit, and the folium is not clearly distinguishable. Additionally, the length of sutural incisions is about half the distance from the umbilicus to peripheral edge in H. calvifacta , whereas in H. foraminulosa , it is about a quarter. Lei and Li (2016) did not provide SEM images or detailed images of the type specimens, and neither difference between individuals in the description, the convexity of the umbilical side and spiral side in lateral view, and the inclination from the umbilicus to periphery, appear in a rather wide range.

Distribution. Korea, China.

Class Nodosariata Mikhalevich, 1992 emend. Rigaud et al., 2015

Order Polymorphinida Mikhalevich, 1980

Family Ellipsolagenidae A. Silvestri, 1923

Genus Oolina d’Orbigny, 1839

Figures

Plate 2. Photomicrograph and SEM image of the newly recorded species. All scales are 100 μm unless otherwise noted. 1-4. Hemirotalia foraminulosa Lei and Li, 2016; 1. (a-c) MABIK PR00044175; 1a. Ventral side view, SEM image; 1b. Lateral view, SEM image; 1c. Spiral side view, SEM image. 2. (a-e) MABIK PR00044176; 2a. Ventral side view, SEM image; 2b. Lateral view, SEM image; 2c. Spiral side view, SEM image; 2d. Spiral side view, photomicrograph; 2e. Ventral side view, photomicrograph. 3. (a-f) MABIK PR00044178; 3a. Ventral side view, SEM image; 3b. Lateral view, SEM image; 3c. Spiral side view, SEM image; 3d. Ventral side view, photomicrograph; 3e. Lateral view, photomicrograph; 3f. Spiral side view, photomicrograph; 4. (a, b) MABIK PR00044177; 4a. Ventral side view, photomicrograph; 4b. Lateral view, photomicrograph. 5-7. Oolina brevisolenia Zheng, 1979; 5. (a, b) MABIK PR00044179; 5a. Lateral view, SEM image; 5b. Basal view, SEM image. 6. (a-c) MABIK PR00044180; 6a. Lateral view, SEM image; 6b. Apertural view, SEM image; 6c. Close-up of aperture, SEM image. 7. MABIK PR00044181; Lateral view, photomicrograph under bright field, white arrow pointing entoso- lenian tube.