Coniogramme sinensis, Ching, 1974

Zhao, Junwen, Yang, Wenli, Wang, Caihong & Zhang, Gangmin, 2018, The identity of Coniogramme wilsonii (Pteridaceae), Phytotaxa 358 (1), pp. 76-82 : 76-79

Identity of Coniogramme sinensis

Coniogramme sinensis Ching (1974: 210) was published by Ching (1974) from Haopingsi, Taipai Shan, Mei County, Shaanxi. The key characteristics of the species are the lustrous, reddish-purple stipes, the hairs on the backs of the laminae, and hydathodes that extend into the teeth. After thorough study of the protologue of C. wilsonii , however, we found that its key characteristic is almost the same as that of C. sinensis , except that the former species has some areoles on the pinnule, whereas the latter one has no areoles.

In the protologue of Coniogramme wilsonii , the author stated that it was described on the basis of only one specimen (holotype, E. H. Wilson 1457), which is deposited in B. However, we found a duplicate (isotype, Fig. 1B ) deposited in K. By comparing the two specimens, we found them to be different in the number of areoles. On the holotype, we can observe 42 areoles on its 9 pinnules, and each pinnule has areoles ; however, on the isotype, we found only 6 areoles on its 23 pinnules, and some pinnules had one or two areoles, while others had none. This indicates that the number of areoles per pinnule is not stable within C. wilsonii and it cannot be used as a reliable character in recognizing the species.

After detailed study of the holotype of C. sinensis, P.C. Tsoong 187 ( Fig. 3A ), we also found 12 areoles on its 21 pinnules. Furthermore, examination of wild C. sinensis populations around the type locality showed some individuals to have a few areoles on the pinnule occasionally, which is consistent with C. wilsonii ( Table 1). Hence, we can conclude that the two taxa are conspecific, and C. sinensis should be considered as a synonym of C. wilsonii .

Figures

FIGURE 1. Types of Coniogramme wilsonii and details. A. Holotype (E.H. Wilson 1457); B. Isotype (E.H. Wilson 1457); C. Hydathodes and teeth on the isotype; D. Areole on the isotype; E & F. Hairs on the isotype. Scale bars C–E: 2 mm; F: 100 μm.

FIGURE 3. Holotype of Coniogramme sinensis deposited in PE (P.C. Tsoong 187). A. Type; B. Areole. C–D. Hairs on the back of the lamina. E. Hydathodes and teeth; F. Hairs on the back of the lamina. Scale bars B, E, F: 2 mm; C & D: 100 μm.