Siphulopsis

Siphulopsis is a single-species fungal genus in the family Icmadophilaceae.^[2][3] This monotypic genus the contains the fruticose lichen species Siphulopsis queenslandica, found in Australia. This lichen was originally described by Gintaras Kantvilas in 2018.^[4] He tentatively classified it in the genus Knightiella due to morphological similarities with Knightiella eucalypti (since transferred to the genus Knightiellastrum), but molecular phylogenetics revealed it to constitute a distinct lineage.^[5]

Siphulopsis
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Lecanoromycetes
Order:	Pertusariales
Family:	Icmadophilaceae
Genus:	Siphulopsis Kantvilas & A.R.Nilsen (2020)
Species:	S. queenslandica
Binomial name
Siphulopsis queenslandica (Kantvilas) Kantvilas & A.R.Nilsen (2020)
Synonyms[1]
Knightiella queenslandica Kantvilas (2018)

The genus name Siphulopsis combines the name Siphula, referring to a similar genus, with the Greek suffix -opsis, which denotes resemblance. This naming reflects the similarity in thallus morphology between this species and those of Siphula.^[5]

Description

The species Siphulopsis queenslandica initiates its growth as small, scale-like patches (squamulose) and soon develops into shrub-like, cushioned clumps (fruticose), typically presenting a whitish to pale ashen-grey colour. This species lacks rhizines (root-like structures for attachment). Upon examination of a cross-section of the thallus, a pseudocortex can be observed. This outer layer is about 20–30 μm thick and consists of poorly differentiated, short-celled hyphae, each approximately 5 μm wide. This layer also contains sporadically interspersed dead cells of its photosynthetic partner, a unicellular green alga. The algal cells are spherical and measure between 6 and 10 μm in diameter.^[5]

Reproductive structures known as ascomata are not observed in this species. However, it possesses pycnidia, which are small, flask-shaped structures embedded within the thallus, producing bacilliform (rod-shaped) conidia, which are involved in asexual reproduction.^[5]

The chemical composition of Siphulopsis queenslandica includes thamnolic acid, a secondary metabolite common in many lichen species.^[5]

The generic description of Siphulopsis references its fruticose thallus that contains thamnolic acid, which is somewhat similar to Siphulaebut lacks rhizines and is not genetically related to this genus.^[5]