Oeosporangium tenuifolium (Burm. fil.) Fraser-Jenk. & Pariyar, Annot. Checkl. Ind. Pterid. 1: 261 (2016) (syn: Trichomanes tenuifolium Burm.f.; Acrostichum tenue Retz.; Adiantum cicutifolium Lam.; Adiantum tenuifolium (Burm.f.) Sw.; Adiantum varians Poir.; Allosorus depilatus Kuntze; Cassebeera tenuifolia (Burm.f.) J.Sm.; Cheilanthes hispidula Kunze; Cheilanthes humilis (G.Forst.) P.S.Green; Cheilanthes micrantha Wall.; Cheilanthes moluccana Kunze; Cheilanthes rupestris Wall.; Cheilanthes sciadioides Domin; Cheilanthes semiglabra (Kunze) Fée; Cheilanthes shirleyana (Domin) H.Quirk & T.C.Chambers; Cheilanthes tenuifolia (Burm.f.) Sw.; Cheilanthes tenuifolia subsp. queenslandica Domin; Cheilanthes tenuifolia subsp. shirleyana Domin; Cheilosoria javensis Trevis.; Cheilosoria tenuifolia (Burm.f.) Trevis.; Gymnogramma microphylloides Ces.; Notholaena glabra Brack.; Hemionitis tenuifolia (Burm. fil.) Christenh.; Notholaena hirsuta var. glabra Bonap.; Notholaena sciadioides (Domin) F.M.Bailey; Notholaena semiglabra KunzePellaea depilata Baker; Pteris alpina Field; Pteris humilis G.Forst.; Pteris nigra Retz.);
Tropical & Subtropical Asia to Pacific: Andaman Is., Assam, Bangladesh, Borneo, Cambodia, Caroline Is., China South-Central, China Southeast, East Himalaya, Fiji, Hainan, India, Laos, Lesser Sunda Is., Malaya, Maluku, Marianas, Marquesas, Myanmar, Nepal, New Caledonia, New Guinea, Northern Territory, Philippines, Queensland, Samoa, Society Is., Solomon Is., Sri Lanka, Taiwan, Thailand, Tonga, Tubuai Is., Vanuatu, Vietnam, West Himalaya as per POWO;

Requesting a fern id: 2 high res. images.
Found growing in Rocky crevices of cliffs.
It has a intricately patterned frond. 
Found in IISER TVM campus adjoining Agasthyamalai biosphere reserve.

Cheilanthes mysorensis

That’s a very widespread species Cheilanthes tenuifolia. Nowadays it is known that Cheilanthes is a complex group of various different genera (though a bit over-split molecularly in N. America).  The microgenus for this  species was Cheilanthosoria, according to the late Professor Ren Chang Ching (Beijing), but the correct and oldest name is Oeosporangium, so nowadays it is Oeosporangium tenuifolium.
Current molecular work on the Cheilanthoid genera is being done in America and will be very interesting, but will likely be too oversplit into some unrecognisable “genera” for some groups.
O. tenuifolium occurs almost throughout India except the further west Himalaya (just getting into Uttarakhand, from Nepal, where it is very common)..
It has strange roots with many tiny swollen lateral tips to each, suggesting possible mycorrhizal VAM symbiosis – which, if so, might explain why it is extremely difficult to get transplanted plants to survive – though I have managed it in Nepal some years ago after many tries.


Requesting a fern id (07112021): 1 high res. image.
Habit: Herb
Found growing extensively on the rock crevices.
The frond is extremely intricate in architecture.

This is Oeosporangium tenuifolium, native – is a cheilanthoid fern,
I think you had it before, already?



References: POWO (Hemionitis tenuifolia (Burm. fil.) Christenh.) Catalogue of Life  The Plant List Ver.1.1  Tropicos  IPNI  GBIF (High resolution specimens)  Flora of China  FOC illustration  Flora of peninsular India  India Biodiversity Portal

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