Nelumbo - The Bulletin of the Botanical Survey of India

V. S. Bir ¹, Kamla Devi ¹

Affiliations
1 Punjabi University, Patiala, IN

Abstract

The present taxonomic account has indicated that the genus Phymatodes is clearly distinct from Microsorium and cannot be merged with that genus as had been done previously by certain authors. It is represented in India by 16 species and the members of this genus usually possess fronds borne on frondiferous bases, thick coriaceous texture and sunken sori. The Indian species referable to Crypsinus are not at all distinct from the members of Phymalodes. As far as venation is concerned Phymalodes erythrocarpa resembles very closely species of Polypodium in having areolae often with one included free veinlet but it can be separated from members of that genus because cf its subcoriaceous texture and altogether different sporangial paraphyses. The lateral pinnae in case of Phymalodes steivartii are characteiistically drawn upwards. Phykiatodes crenalo-pinnata can be differentiated from the other Indian members of genus in having deltoid flonds with elongated apex, the basal pinna lobes irregularly and deeply pinnatifid and the wavy crenations of these lobes. Phymatodes ebenipes is very distinct in itself because of the large frondiferous leaf bases, and ebeneous black polished scales. This fern is separated from other members of the group as P. oxyiwa, P. montana and P. haslata by mainly the characters of rhizome scales. The Himalayan examples of P. ebenipes are separated into the typical foim and var. oakesii (Clarke) Bir and Devi in which case the number of pinnae is much larger than the typical form and the sinuses in between the two pinna lobes are wide and rounded at lase.

The trilobed fronds are met with in all the three species, namely, P. hastata, P. oxyloba and P. montana but these can be separated by the fact that ife P. montana the margin of pinna lobe is repand-crenate and in P. oxyloba and P. hastata it is smooth. But in P. hastata as compared to P. oxyloba the texture is extremely thick, the main lateral veins are prominently raised on undersurface, and finally the pinnae are much broader. In P. oxyloba the texture is thinly subcoriaceous. In all of these species the base of the frond is decurrent on the stipe below. It may be pointed out that the South Indian material generally referable to P. oxyloba has been found to belong to an altogether different species, P. montana which possesses pinnae with crenate repand margin. P. oxyloba is not At all met with in South India.

As compared to the rest of the members of the genus, in P. nigrescens, P. longissima, P. scolopendria, P. banerjiana and P. cuspidala the rhizome scales are clathrate. Also in P. scolopendria and P. banerjiana the sori are in 2-3 irregular rows on either side of the midrib whereas in rest of the Indian species these sori are in one row.

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