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Bolbitis Schott

Small to medium-size terrestrial ferns, lithophtes or subepiphytes. Rhizome short-creeping, or low-climbing (rarely high-climbing), slender to stout, unbranched or with accessory branches, bearing roots ventrally and fronds in 2-6 dorsal rows, dictyostelic with a large, +/- channelled ventral strand producing root traces, and 1-3(-5) dorsal strands, large overlapping leafgaps with leaf traces of several to many strands arranged in a simple ring, scales on the young parts +/- flat, broad, thin, subcordate, perfoliolate or basally attached, opaque or clathrate, the margins with uniseriate dark-tipped glandular hairs. Fronds long-stipitate, the stipe abaxially rounded, adaxially with 2 lateral and 1(-3) medial ridges, becoming rounded basally, 2 continuous lateral aerophores decurrent with the stipe into the rhizome, vascular bundles in a simple open ring, the 2 adaxial bundles larger, lamina simple, pinnate, (rarely bipinnate), the pinnae constinuous or subarticulate with the rachis, terminal segment triangular or conform to the pinnae, the margins subentire to variously lobed, with or without teeth in the sinuses corresponding tot he acroscopic branch of a vein group, subcoriaceous to herbaceus, glabresent, veins pinnately arranged in pinnate groups with the main lateral veins often evident, free or anastomosing with or without ex- or recurrent, simple or forked free included veinlets; fertile fronds with a contracted lamina and a longer stipe. Sporangia usually acrostichoid, sometimes with a non-contracted median band of lamina or moniliform, along veins or all over the abaxial surface of the lamina, exindusiate, paraphyses lacking, annulus longitudinal, interrupted, of 12 - 18(-20) thickened cells. Spores monolete, with a smooth to cristate or cristate-undulate perispore.

Species in Papuasia

1a. Apex of frond an unlobed free pinna of similar size and shape to lateral pinnae (sometimes very elongate); lamina mostly with 1-3 pairs of lateral pinnae, if stunted and simple-fronded the lamina not lobed at the base; margins entire or shallowly sinuate without teeth in the sinuses; venation with areoles of differing size, shape and orientation, not decreasing in size towards the margin 2
Apex of frond with gradually reduced pinnae, the apical segment mostly triangular and lobed at the base, formed by the union of decrescent pinnae; lamina with up to 30 or more pairs of pinnae, if stunted and simple-fronded, the lamina lobed at the base; margins deeply or moderately crenate or sinuate, often with bristle-like teeth in the sinuses; veins poorly and irregularly anastomosing, or with regular arep;es +/- decreasing in size towards the margin 3
2a. Lamina herbaceus, thin when dry, veins readily evident; terminal segment often very elongate, rampant and producing new plants; plants growing among rocks streams B. heteroclita
Lamina thicker, stiff when dry, veins indistinct; terminal segment the same shape as lateral pinnae although sometimes slightly larger, never linear and rampant; plants of forest floor, the rhizome often ascending the boles of trees. B. sinuata
3a. Bulbil terminal, the upper pinnae gradually reduced to minute lobes and a linear whip-like terminal segment; veins poorly anastomosing in small plants, with 1-3 series of oblique costal areoles in larger specimens, constules often poorly developed B. novoguineensis
Bulbil subterminal, the upper pinnae reduced (but never minute) into a large triangular terminal segment lobed at the base; veins copiously anastomosing in 1-2 series of oblique costal and costular areoles, costules nearly always evident. 4
4a. Lamina thick, stiff when dry, veins mostly indistinct; margins +/- entire to sinuate-crenate, very rarely with bristle-like teeth in the sinuses; lateral pinnae mostly 1-6 pairs B. rivularis
Lamina herbaceus, thin when dry, veins readily evident; margins regularly crenate with fine teeth on the crenations and prominent bristle-like teeth in the sinuses; lateral pinnae mostly 7-25 pairs B. quoyana

In Papuasia Bolbitis quoyana (s.l.) is a very complex and variable species, in which several geographic entities can be recognized; some have been described as species in the past but they probably deserve a lower rank;

Species in Papuasia

1a. Small plants to c.25 cm tall with few pairs of lateral pinnae; pinnae shallowly crenate, not deeply pinnatifid, costules not evident (NE New Guinea) B. quoyana "entity parva"
Moderate sized plants c.40-80 cm tall with 7 or more pairs of lateral pinnae; pinnae with 7 or more pairs of lateral pinnae; pinnae with moderate to deep crenations, costules readily evident.
2a. Sporangia on fertile pinnae confined to a sinuate sorus constinuous along the margin, with an obvious region of green lamina either side of the costa B. quoyana "entity Milne Bay"
Sporangia completely covering lower surface of fertile pinnae 3
3a. Robust ferns with +/- pectinate fertile pinnae B. quoyana "entity Manus/ Solomons" (?B. naumannii)
Smaller ferns with +/- sinuate fertile pinnae B. quoyana for the most part.