Diplazium latifolium T. Moore, Index Fil. 141 1859. (syn: Allantodia calogramma (Christ) Ching; Allantodia matthewii (Copel.) Ching; Asplenium latifolium D.Don (ambiguous synonym); Asplenium woodwardioides Roxb. (ambiguous synonym); Athyrium matthewii Copel.; Diplazium calogrammum Christ; Diplazium dilatatum f. diversifolium C.Chr.; Diplazium diversifolium (C.Chr.) Sarn.Singh & Panigrahi (ambiguous synonym); Diplazium grosselobatum C.Chr. ex Wu; Diplazium indicum Nair; Diplazium matthewii (Copel.) C.Chr.; Diplazium woodwardioides Panigrahi (ambiguous synonym));
Indian Subcontinent to S. China and N. Indo-China, Philippines: Assam, China South-Central, China Southeast, East Himalaya, India, Laos, Nepal, Philippines, Sri Lanka, Vietnam as per POWO;
China (SE-Yunnan, Fujian, Guangdong, Guangxi), N-Vietnam, Laos, Myanmar [Burma], Nepal, Bhutan, India (Sikkim, NE-India, S-India), Sri Lanka as per Catalogue of Life;
Diplazium dilatatum SN15420a : 3 posts by 2 authors. Attachments (1) – 3 mb.
No, that’s not D. dilatatum, but D. latifolium. I think your identification references are a little out of date! Reports of D. dilatatum from South India are misidentifications for D. latifolium, which latter occurs in both the N.E. and south of India. I have not yet seen any correct collections of D. dilatatum from South India in any herbarium, or from my own collections, though I’ve seen many misidentifications as it. As I published in Indian Checklist 2, it is almost certainly absent from South India.
Note the long, long sori, and the rather separate rectangular lobes of the pinnae – of D. latifolium, and texture of lamina more succulent.
However, the specimen is not a good example – as for all Diplazium we need to see the scales at the stipe-base. If this is not carefully preserved on the sheet (without rubbing the scales off), the specimen is inadequate- and may be unidentifiable in the case of other more difficult species of Diplazium and some other genera.
D. dilatatum has many very narrow, almost fibril-like, brown scales running up from the stipe-base to half-way up the stipe, getting smaller and almost absent further up the stipe. But D. latifolium has few, short, broad, very black, crinkly scales confined to the stipe-base, the stipe-base usually being papillate at the very base, which is more easily visible in living plants.
Both have very thick ascendent rhizomes, but both can give rise to thin, long-creeping runners with small plants with less dissect, but sometimes fertile fronds at their apices – especially in D. dilatata.
A Revised Handbook to the Flora of Ceylon, Vol. XV, Part B: Ferns …, Part 2 edited by Monika Shaffer-Fehre (2006)