Skylonia sandbergi Sandberg, 1962

Sonar, Mohan A., Pawar, Ravi V. & Wayal, Dnyaneshwar V., 2022, Newly discovered species of cheilostomatid Bryozoa from the Miocene of western Kachchh, Gujarat, India, European Journal of Taxonomy 821, pp. 16-39 : 35

Skylonia sandbergi Sandberg, 1962

Fig. 12 ; Table 11

Material examined

INDIA • 21 specs; Yellow limestone of Waghot section, Burdigalian, lower Miocene, Chhasra Formation; 23°25′35″ N, 68°42′20″ E; Jan.–Feb. 2012; Pawar leg.; GIS/B 0549 to 0569 .

Description

Colony spindle-shaped having six to nine zooids, more or less rectangular in each longitudinal row ( Fig. 12A ). Length and width of a few complete spindles vary between 0.8 mm and 0.3 mm, respectively. Spindles have maximum diameter at or just below central point. Width/length ratio of median zooids varies between 0.3 mm to 0.8 mm. Width of apertures ranges from 0.05 mm to 0.07 mm. Apertures above greatest diameter of spindles open obliquely upwards. End of frontal cover depressed, forming shallow groove. Usually very well-developed knobs bordering aperture ( Fig. 12B ).

Remarks

The present Kachchh species differs from Skylonia mirabilis Thomas, 1961 in the shape of the autozooids and orifice (see Keij 1973: 224, pl. 3 figs 10–13). Compared to the present species, S. dohmi ( Sandberg, 1962) and S. thomasi Keij, 1973 have fewer autozooids in each longitudinal row, knobs adjoining the orifice, and a raised border around the orifice. Skylonia malabarica Sonar & Badve, 2019 differs in the number of zooids and the nature of the knobs around the orifice.

Figures

Fig. 12. Skylonia sandbergi Sandberg, 1962 (GIS/B 0549). A. General view of the colony showing autozooids and well-developed knobs bordering the aperture. B. Close-up of the colony showing autozooids and well-developed knobs (arrows).