Fig. 3 in New materials of multicellular algae from the earliest Cambrian Kuanchuanpu biota in South China

Fig. 3. SEM images of problematic alga Calathophycus irregulatus Tang gen. et sp. nov. with a deep central concavity; Kuanchuanpu Formation, Fortunian, Terreneuvian, Cambrian in Ningqiang County, Shaanxi Province, China. A. ELISN72-52, holotype; A1, front view; A2, back view. B. ELISN163-729; B1, front view; B2, back view. C. ELISN133-60. D. ELISN163-339. Cell clumps, white arrows (A, C, D); gaps between cell clumps, black arrows (A, B1). Fossils are arranged in order of size, suggesting a possible sequence of growth and development.