Tapellaria granulosa is a species of corticolous (bark-dwelling) crustose lichen in the family Ectolechiaceae. It was described from subtropical Florida and has a pale green thallus (lichen body) that is densely covered with fine, granule-like outgrowths. It also has black apothecia (disk-like fruiting bodies) and ascospores (spores divided into many small compartments).
Tapellaria granulosa was described as a new species in 2011 by Robert Lücking and Eimy Rivas Plata (MycoBank no. 560012), based on a collection made in Fakahatchee Strand Preserve State Park (Collier County, Florida). The holotype (the specimen the name is based on; Lücking & Rivas Plata 26810) was collected in March 2009 along Janes Scenic Drive, about north-northwest of the ranger station, in a TaxodiumâÂÂSabal hammock. It is deposited in the Field Museum herbarium (F), with an isotype (a duplicate type specimen) in the University of South Florida herbarium (USF). The specific epithet granulosa refers to the finely and densely granulate thallus surface, described as unusual within the genus.
The thallus (lichen body) is corticolous (growing on bark) and forms a continuous crust 2âÂÂ5 cm across and about 30âÂÂ50 micrometers (üm) thick. Its surface is pale green and densely , giving it an isidia-like ("") appearance. The granules are described as clusters of cells wrapped in fungal hyphee; the photobiont is (a green alga). The apothecia are (sitting directly on the thallus), rounded to irregular, and 0.5âÂÂ1 mm in diameter (180âÂÂ270 üm high). The is initially flat but becomes convex with age; it is black to brownish black, with a thin, persistent black margin. Under the microscope, the paraphyses are branched and anastomosing (net-like). The asci (spore sacs) measure about 90âÂÂ120 à18âÂÂ28 üm and contain 4âÂÂ8 ellipsoid, muriform ascospores. The spores measure about 20âÂÂ25 à10âÂÂ15 üm and have 3âÂÂ5 transverse septa and 1âÂÂ2 longitudinal septa per segment. (asexual spore-producing structures) are also present (0.4âÂÂ0.6 mm broad and 0.7âÂÂ1 mm long). They produce (thread-like), curved conidia (asexual spores) that are 5âÂÂ7-septate and about 40âÂÂ50 à2 üm. No lichen substances were detected by thin-layer chromatography.
The species was originally known from two collections from Fakahatchee Strand Preserve State Park, where it grows on the bark of Taxodium. It was treated as closely related to Tapellaria malmei from the same locality, sharing similarly small muriform ascospores (4âÂÂ8 per ascus) but differing in its distinctive granular thallus. The granules were interpreted as unlikely to function as true isidia and may instead increase thallus surface area. Similar between-species variation in thallus texture has been compared with patterns reported in the related genus Lasioloma. Tapellaria granulosa has also been documented from Santa Cruz Island in the Galápagos.