Lycopodiaceae

Øllgaard, Benjamin, Boudrie, Michel & Cremers, Georges, 2020, The Lycopodiaceae of Guyana, Suriname, and French Guiana, Phytotaxa 433 (2), pp. 101-134 : 102-103

Key to the genera of Neotropical Lycopodiaceae

1 Stem dichotomies equal (isotomous) throughout, without elongate, indeterminate main stems; roots usually forming one basal tuft; sporophylls and vegetative leaves alike, or the sporophylls, if smaller, persisting and green, not subpeltate and ephemeral; sporangia axillary; spores foveolate-fossulate.......................................................................................................... 4. Phlegmariurus

– Stem dichotomies unequal (anisotomous) throughout (pseudomonopodial), the branches differentiated into elongate, indeterminate, rhizomatous, or creeping, looping, trailing or scandent main stems, rooting at intervals, and usually determinate branchlet systems; sporophylls strongly modified, ephemeral, unlike vegetative leaves, subpeltate or peltate, aggregated in compact, terminal strobili; sporangia borne on sporophyll bases or axillary, spores reticulate or rugate.....................................................................................2

2 Strobili sessile, pendent or nodding, terminating amply branched aerial branchlet systems ........................................ 3. Palhinhaea

– Strobili sessile or pedunculate, erect, terminating simple, erect branches or ascending branchlet systems ......................................3

3 Branching dorsolateral throughout, strobili sessile or pedunculate, terminating branchlets; leaves with a hyaline apex; sidewalls of sporangial epidermal cells lignified, strongly sinuate, spores reticulate .............................................................2. Lycopodium s. str.

– Branching of horizontal shoots flabellate, strobili terminating simple branches that arise dorsally on the creeping stems; leaves without hyaline apex; sidewalls of sporangial epidermal cells straight, non-lignified, except for nodular or semiannular internal thickenings; spores rugate ..................................................................................................................................................................4

4 Sporophylls nearly twice as wide as adjacent peduncle leaves, or wider, ovate to ovate-lanceolate, of different colour and texture than peduncle leaves, the margins minutely rugose to minutely fimbriate-denticulate, usually 10(–12)-seriate; sporangia isovalvate, attached to the upper side of the sporophyll; creeping shoots isophyllous to strongly anisophyllous with wide and long lateral leaves and narrow dorsal leaves; sporangium epidermal cells with incompletely semiannular thickenings... 5. Pseudolycopodiella

– Sporophylls slightly wider to ca 1.5 times than adjacent peduncle leaves and of the same colour and texture, linear-lanceolate to ovate- lanceolate, with few to several sharp, long and often recurved teeth, (10–)12–20-seriate; sporangia anisovalvate, axillary; creeping shoots isophyllous or nearly so; sporangium epidermal cells with completely semiannular thickenings............................. ..................................................................................................................................................................................... 1. Lycopodiella