Myelochroa macrogalbinica
Myelochroa macrogalbinica is a species of corticolous foliose lichen in the family Parmeliaceae. Found in India, it was described as a new species in 2001.
Taxonomy
Myelochroa macrogalbinica was formally described as a new species in 2001 by the lichenologists Pradeep Divakar, Dalip Kumar Upreti and John Elix. The type specimen was collected by Ajay Singh on 22 May 1972, and is housed in the lichen herbarium at LWG. The species differs from the widespread Myelochroa galbina in having loosely thallus, broader, and larger apothecia with larger spores.Description
Myelochroa macrogalbinica has a thallus that grows up to 8 cm wide. Its lobes are overlapping like roof tiles, sublinear to subirregular in shape, irregularly branched, apically subrotund, 2–6 mm wide, and have margins. The cilia are dense, simple, regularly dispersed, and 0.5–1.0 mm long. The upper surface is pale grey becoming pale brown when preserved in herbariums. It is flat to, shiny at the apices but dull within, with a white- appearance, and lacks both isidia and soredia.The medulla is lemon-yellow to pale yellow. The lower surface is black with a brown narrow marginal zone. The rhizines are dense, black, simple or branched, and 1–2 mm long.
A distinguishing feature of this species is the presence of apothecia, which are common, substipitate, 2–15 mm wide, and initially shallowly concave before becoming flat and undulate-distorted with age. The apothecia are dark brown with a thin margin. are broadly ellipsoid, measuring 14–25 by 9–13 μm. The species also has black, immersed pycnidia with weakly bifusiform conidia measuring 4.5–6.5 by 1 μm.