Campylopus arctocarpus (Hornsch.) Mitt.

P. A. Florschütz, 1964, Flora of Suriname, volume VI, part I, Leiden: Brill : 73-24

3. Campylopus arctocarpus (Hornsch.) Mitt. Journ. Linn. Soc. London Bot. 12: 87. 1869.

Dicranum arctocarpum Hornsch. Fl. Bras. 1 (2): 12. 1840.

Type specimen _ Sellow s.n., Argentina (BM, K).

C. roraimae Broth. Trans. Linn. Soc. London Bot. ser. 2.6: 89. 1901.

Type specimen: McConnell & Quelch 347, British Guiana (K).

Yellowish-green to golden green plants, growing in rather dense mats. Stems up to 4 cm long, sparingly and irregularly branched, densely reddish-tomentose, equally foliate. Leaves more or less appressed or erect-spreading, at apex sometimes a little falcate, slightly flexuose when dry, linear-lanceolate, concave, gradually narrowed to the channelled, acute apex, about 9 mm long and 0,5 mm wide, margin distantly serrate near apex, rarely smooth. Costa excurrent, the excurrent part toothed all around, rarely nearly smooth, on back ridged, smooth to finely and distantly serrate, in cross-section showing 2 bands of stereids. Alar cells inflated, brownish-red, forming distinct auricles; cells just above the auricles rectangular in a few rows, with thick, pellucid, pitted walls, 24-50 µ long and 9-15 µ wide, much narrower and more or less hyaline towards margin, forming an inconspicuous border; towards mid-leaf cells gradually longer and narrower, 60-90 µ long and 6-9 µ wide with strongly pitted walls, at 1/2 of length of leaf irregular rhomboidal to rectangular, 6-15 µ long and 4-7 µ wide, in upper 1/3 of leaf only 3-4 rows along costa, rather irregular, transversely elongate to subquadrate, rhomboid or elongate rectangular, 8-17 µ long (rarely a few cells up to 27 µ) and 3-7,5 µ wide. Often more than one perichaetium on a stem; outer perichaetial leaves from an ovate, subclasping base rather quickly narrowed to a long, linear point, about 4 mm long. Inner perichaetial leaves with a long sheathing base, 4 mm long, narrowed to a short point, about 2 mm long. Seta erect, usually straight, up to 1,5 cm long, slightly scabrous above. Capsule oblong, asymmetric, curved, 1,5-2,25 mm long, furrowed when empty, neck distinct, slightly scabrous. Peristome about 460 µ high, teeth forked half way down, finely vertically striate below and densely papillose above. Annulus large. Lid long-rostrate, about 1 mm long. Calyptra cucullate, ciliate at base. (Fig. 20)

Distribution West Indies, Central and South America.

On rocks and on fallen trees. Apparently rather rare and confined to higher altitudes, mostly in the mossy forest. Van Asch van Wijck Mountains (500 m), Emma Range (850 m), Wilhelmina Mountains, including Tafelberg, up to 900 m. Also in British Guiana. Not collected in French Guiana.

Specimens examined: B.W. 7052, 7053B; Maguire 24433M2 (NY, K, U, as C. richardii ); Florschiitz 1478; Daniels & Jonker 916. British Guiana: McConnell & Quelch 347 (K, type of C. roraimae ).

Costal structure, shape of cells, especially in the upper part of leaf, the straight seta and the ciliate calyptra are sufficient characters to recognize this species. Of the two specimens, identified by Bartram as C. richardii from Tafelberg, one belongs here and the other belongs to C. harrisii .