Astrothelium inspersoconicum

Astrothelium inspersoconicum
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Ascomycota
Class:	Dothideomycetes
Order:	Trypetheliales
Family:	Trypetheliaceae
Genus:	Astrothelium
Species:	A. inspersoconicum
Binomial name
Astrothelium inspersoconicum Aptroot & Weerakoon (2018)
Holotype: Runakanda – Maguru Ganga area of Sri Lanka

Astrothelium inspersoconicum is a species of corticolous (bark-dwelling), crustose lichen in the family Trypetheliaceae. Found in Sri Lanka, it was described as a new species in 2018.

Taxonomy

The species was officially described by the lichenologists André Aptroot and Gothamie Weerakoon in 2018. The type specimen was collected by the second author in the Runakanda – Maguru Ganga area of Sri Lanka, at an elevation of 249 m (817 ft). The epithet inspersoconicum reflects the unique combination of an inspersed hamathecium and its association with the conicum-aggregate group within the genus Astrothelium, which is a rare feature in this group.

Description

Astrothelium inspersoconicum has a corticate, smooth, and somewhat shiny thallus covering areas up to 15 cm (6 in) in diameter, with a pale greenish-grey hue and a distinct brown, glossy prothallus line. Its ascomata (fruiting bodies) are pyriform and primarily aggregated, with a carbonised wall and eccentric, fused, and conical ostioles covered by an orange pruina. The hamathecium of the species is inspersed with oil globules, a distinguishing feature. It carries hyaline, fusiform (tapered) ascospores that have three septa (internal partitions) with diamond-shaped lumina, and measure 23–25 by 7–8 μm.

It is closely related to Astrothelium cinnamomeum but can be distinguished by its inspersed hamathecium. It represents a rare instance within the Astrothelium conicum-group, in which the hamathecium is typically not inspersed.

Habitat and distribution

This species is found in Asia, specifically recorded in Sri Lanka.