Syrrhopodon hongkongensis (Calymperaceae, Musci), a New Species from Hong Kong, China

Abstract

Syrrhopodon hongkongensis sp. nov. is described from Hong Kong, China. It is closely related to S. chenii, but differs in having strong, dense spines and papillae on both dorsal and ventral surfaces of the costa. Compared with most moss families in China, the Calymperaceae are relatively well known (Lin 1996; Reese & Lin 1991). However, Reese and Lin (1991) pointed out is likely that future exploration of tropical and subtropical China will reveal further new records and undescribed taxa.... Detailed study of recent collections from Hong Kong confirms the truth of this prediction as a previously undescribed species of the genus Syrrhopodon has been found. SYRRHOPODON HONGKONGENSIS L. Zhang, sp. nov. FIGS. 1-12 Syrrhopodon chenii Reese & P-J. Lin affinis, sed differt costis dorsalibus et ventralibus dense spinis et papillis. TYPE: CHINA. HONG KONG. New Territories, Sheung Wo Hang Fung Shui Wood, on tree trunk in forest, 160 m, Zhang 1079 (Holotype, IBsc; isotypes, HKU, KFBG, LAF). Same locality, 130 m, on thin soil over rock in forest, Zhang 1074 (HKU, IBSC, KFBG); 145 m, on tree trunk in forest, Zhang 1078 (HKU, IBSC, KFBG)-All paratypes. Mature plants small, light green, loosely gregarious or cespitose, stems elongate, simple or forked, rhizoids dark red, conspicuous, 5-8 mm high including leaves. Axillary hairs inconspicuous. Leaves crowded, older ones in lower parts fragile and often broken or eroded. Upper leaves slightly secund or arcuate-ascending when dry, erectspreading when wet, apex acute to obtuse, 2.0-4.5 mm X 0.22-0.43 mm. Leaves narrowly linear or lanceolate above base. Upper lamina margins distinctly involute both dry and moist. Cells of upper lamina pellucid, isodiametric or rectangular, 5-8 sm diameter, bulging ventrally, smooth dorsally except towards margin, there with several rows of cells with spines and papillae. Margins of upper lamina bordered by hyaline, elongate cells these often appearing distinctly toothed due to projecting spines and papillae on involute dorsal intramarginal cells. The intramarginal spines 20-30(-40) pm. Margins at shoulders with delicate hyaline cilia and teeth, the cilia 70-90(-105) im in length. Costa strong, ending just below apex, with distinct dense spines and papillae dorsally and ventrally from top of cancellinae, slightly denser on dorsal surface. Spines 30-50(-65) im. Cancellinae nearly filling base, sharply delimited, ending in acute angles distally along costa, formed of 4-7 rows of cells on each side of costa. Gemmae frequent, on ventral surface of leaf tip, fusiform, 0.20-0.27 mm long including a long tail, tails easily broken and gemmae then only 0.10-0.15 mm. Seemingly diocious, perichaetial leaves not differentiated. Archegonia terminal, 0.30-0.35 mm long. Antheridia and sporophytes unknown. This new species shows some morphological diversity between mature and young plants. The young plants are smaller and 3-5 mm in height, with leaves shorter and wider, about 1.8-3.0 x 0.40.5 mm. The surface of the margins of the upper lamina are less prominently toothed or nearly smooth, and the spines and papillae on the dorsal and ventral surfaces of costa are fewer and shorter tha those of mature plants. The only species which can possibly be confused with S. hongkongensis is S. chenii, which also has distinct intramarginal spinose and papillose cells. After our study of the isotype of S. chenii (Redfearn et al. 34406, IBsc) and related literature (Lin 1996; Reese & Lin 1989, 1991), we find that it is not difficult to separate the two species using the characters in Table 1.