Hispidicarpomyces Nakagiri, Mycologia 85(4): 639 (1993)
Sordariomycetes orders incertae sedis, Spathulosporales, Hispidicarpomycetaceae, Hispidicarpomyces
Index Fungorum number: IF26466; Facesoffungi number: FoF 02110; 1 morphological species.
Parasitic on a marine alga. Sexual morph: Ascomata superficial, solitary to gregarious, ostiolate, apapillate. Peridium composed of three-layers: outer layer with thick-walled, short hyphal projections, brown to dark brown, middle layer of light brown to dark brown, thick-walled hyphal, flattened cells of textura epidermoidea, and an inner layer of pale brown, thin-walled, flattened cells of textura epidermoidea, lining the whole ascomatal venter. Paraphyses septate branched. Asci 8-spored, unitunicate, thin-walled, clavate to pyriform, deliquescing early and lacking an apical ring. Ascospores hyaline, ellipsoid to elliptic-fusiform, unicellular, lacking appendages or a sheath, overlapping. Reproductive state of brown hyphae, Spermodochia composed of a mass spermatiosphores. Spermatiosphores, verticilliate, asymmetrical penicilliate-like, brown at the base, paler and hyaline towards the apex. Stipes septate, branched, brown at the base. Spermatia cylindrical, unicellular, hyaline. Trichogynes septate, cylindrical, brown (Hyde et al. 2020).
Type species: Hispidicarpomyces galaxauricola Nakagiri, Mycologia 85(4): 639 (1993)
Notes: Hispidicarpomyces was introduced by Nakagiri (1993) and is a monotypic genus which shares similar morphological features with Spathulospora. There is no sequence data available for this genus; therefore, further taxon sampling is essential to determine its phylogenetic position within the Ascomycota (Jones et al. 2015, 2019).
The single species in the genus, H. galaxauricola, has been reported to be biotrophic on the marine alga Galaxaura falcata (Rhodophyta), which was found along the Japanese coast (Nakagiri 1993). Infection of the host alga by the fungus probably occurs in June to July when its ascospores are abundantly released (Nakagiri 1993). Spermodochia and ascocarps are produced from the base up to around the first to third branches of the algal frond. It is believed that the absorption of photosynthetic nutrients from the epithelial cells can be occurring due to dense distribution of hyphae beneath the epithelial layer. However, there was no evidence of hyphal invasion into a host cell, though close contact of the hyphae with algal cells was often observed (Nakagiri 1993).
Hispidicarpomyces galaxauricola is similar to members of Spathulospora in morphology and parasitism on marine red algae (Kohlmeyer 1973, Kohlmeyer & Kohlmeyer 1979). However, they are different in that H. galaxauricola has true hyphae growing throughout the algal frond and, in contrast, those of Spathulospora spp. are reduced-hyphoid (Kohlmeyer 1973). Further, intracellular invasion into the algal cell by an infection peg and formation of intracellular crusts can be seen in Spathulospora species, but H. galaxauricola showed only intercellular infection (Nakagiri 1993).
Species illustrated in this entry:
Hispidicarpomyces galaxauricola Nakagiri
Hyde KD, Norphanphoun C, Maharachchikumbura SSN, Bhat DJ et al. 2020 – Refined families of Sordariomycetes. Mycosphere 11, 305–1059.
Jones EBG, Pang KL, Abdel-Wahab MA, Scholz B et al. 2019 – An online resource for marine fungi. Fungal Diversity 96, 347–433.
Jones EBG, Suetrong S, Sakayaroj J, Bahkali AH et al. 2015 – Classification of marine Ascomycota, Basidiomycota, Blastocladiomycota and Chytridiomycota. Fungal Diversity 73, 1–72.
Kohlmeyer J, Kohlmeyer E. 1979 – Marine mycology: the higher fungi. Academic Press, New York 690.
Kohlmeyer J. 1973 – Spathulosporales, a new order and possible missing link between Laboulbenniales and Pyrenomycetes. Mycologia 65, 614–647.
Nakagiri A. 1993 – A New Marine ascomycete in Spathulosporales, Hispidicarpomyces galaxauricola gen. et sp. nov. (Hispidicarpomycetaceae fam. nov.), inhabiting a red alga, Galaxaura falcata. Mycologia 85, 649.