Phlegmariurus Holub, Preslia

Øllgaard, Benjamin, Kessler, Michael & Smith, Alan R., 2018, Prodromus of a fern flora for Bolivia. II. Lycopodiaceae, Phytotaxa 334 (3), pp. 255-294 : 267

Phlegmariurus Holub, Preslia 36(1): 17, 21. 1964

= Huperzia Bernhardi , pro parte, J. Bot. (Schrader) 1800(2): 126. 1801.

The species of this genus are epiphytic or terrestrial, pendulous, recurved, erect, or ascending, isotomously branched throughout, or sometimes sprouting from the rooting bases of the plants. Roots arise from the stem stele, descend through the cortex to the stem base, where they usually emerge as a basal tuft. Shoots homophyllous or gradually to abruptly heterophyllous, the constriction of distal divisions of heterophyllous species associated or not with presence of sporangia. Sporangiate and vegetative leaves alike, or sporangiate leaves shorter, not peltate, persisting and green after sporangial dehiscence. Sporangia axillary, reniform, isovalvate, with a short slender stalk; side and inner walls of sporangial epidermis cells sinuate, thickened and lignified. Spores foveolate or fossulate. Gametophytes usually subterranean or deep in epiphytic substrate, mycoparasitic, cylindrical with radial or bilateral symmetry, with pluricellular, uniseriate hairs among the gametangia.

Until fairly recently, Phlegmariurus was generally included in Huperzia . However, Phlegmariurus is distinct from Huperzia with regard to spore type and the lack of gemmae. The species of Huperzia are entirely terrestrial, and the majority of Phlegmariurus species are epiphytic. There are no known intergeneric hybrids. According to Wikström et al. (1999) and Field et al. (2016), it appears that the terrestrial species in Phlegmariurus have been derived from epiphytic elements in high montane forests. In Phlegmariurus the sporangia are situated in the axils of sporophylls that may be similar to the vegetative leaves, or reduced in size and occupy major parts of constricted distal divisions in pendulous epiphytes.

Phlegmariurus is pantropical, with about 300 species, and with few temperate species. Species diversity is highest throughout the tropics in evergreen montane forests, and in the wet Andean grass and shrublands in South America. Bolivia has 26 species, of which 2 are endemic.