Gilbert et al.—Himalayan Cambrian microfossils
Type species.—Cupitheca brevituba Duan in Xing et al., 1984; lower Cambrian, Meishucunian Stage, Kuanchuanpu Formation and Qiongzhusian Stage, Xihaoping Formation of China (= C. mira [He in Qian, 1977]).
Diagnosis.—Straight edged or slightly bent conical tubes with distinct constriction of tube diameter at short distance from sealed proximal end. Expansion angle of tube walls 6°–14° in distal part of tube. Cross-section of distal part of tube circular or oval. Proximal parts of tube usually decollate. Ornamentation absent or represented by distinct transverse and longitudinal ribs. Internal surface of tube smooth.
Remarks.—Himalayan specimens are evidently members of this genus because they share the diagnostic straight edged conical tube with a constriction of tube diameter near the proximal end. The expansion angle of the tube walls varies between 6° and 14°, depending on specimen, and the cross-section of the distal part of tube is oval.
Cupitheca sp. Figure 11.6–11.10 Material.—WIMF/A/3991-3995.
Description.—All specimens are preserved in calcium phos- phate and display no internal details or microstructure of the original organism.
Remarks.—As the Himalayan material are all internal molds, no species level designation is possible. Cupitheca occurs in the lower Cambrian of China, Antarctica, Australia, Greenland, Spain and Kazakhstan (Mambetov in Missarzhevsky et Mambetov, 1981; Zhou and Xiao, 1984; Bengtson in Bengtson et al., 1990; Wrona, 2003; Malinky and Skovsted, 2004; Jensen et al., 2010). This is the first occurrence of Cupitheca within the middle Cambrian and within the Himalaya. Singh et al. (2015, fig 3.10) referred a specimen from Stage 4 in the Parahio Formation to ?Cupitheca. This specimen lacks clear preservation of the tubular constric- tion characteristic of this form, and we consider it to be indeterminate.
Occurrence.—From Parahio Formation carbonates collected at 775.41m (PO24, Paramecephalus defossus Zone) above the base of the Parahio Valley section on the north side of the
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Figure 12. Spines indet. All specimens coated with platinum/palladium before SEM imaging. Scale bar represents 200 µm unless displayed otherwise. (1–10) From 776m (PO25) above base of Parahio Valley section, Parahio Formation. (1–3, 5) Forms with straight and curved basal margins. (1) WIMF/A/3996, close-up of (2), showing possible surface ornamentation of equally distributed and sized pores; (2) WIMF/A/3996; (3) WIMF/A/3997, detailed view of (4) displaying possible well-preserved outer surficial detail; (4) WIMF/A/3998, elliptical base; (5) WIMF/A/3998; (6) WIMF/A/3999, elliptical base; (7) WIMF/ A/4000, circular base; (8) WIMF/A/4001, circular base; (9) WIMF/A/4002; (10) WIMF/A/4003, elliptical base.
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