Rhodosticta Woron., Izv. Imp. St.-Peterburgsk. Bot. Sada 11: 13 (1911)
Facesoffungi number: FoF 07575
Sordariomycetes, Sordariomycetidae, Phyllachorales, Phyllachoraceae
Parasitic on the host plant. Sexual morph: undetermined. Asexual morph: Conidiomata yellowish brown, stromatic, pycnidial, usually epiphyllous, scattered to gregarious, immersed, globose to irregular in shape, multilocular, occasionally convoluted, glabrous. Ostiole single to each locule, circular to irregular. Conidiomatal wall composed of thin-walled, loose, hyaline cells of textura angularis in the base and lateral part, merging with a few septate, unbranched, pale brown, hyphal elements extending towards and lining the ostiole. Conidiophores formed from the inner wall layer of the conidiomata, hyaline, cylindrical to subcylindrical, branched at the base, septate, smooth-walled. Conidiogenous cells hyaline, enteroblastic, phialidic, cylindrical to lageniform, usually integrated, determinate, smooth-walled, apertures terminal or on short lateral branches which form immediately below septa, with flared collarettes and marked periclinal thickenings around the apertures. Conidia hyaline, cuneiform to obovoid, rounded at the apex, blunt and truncate at the base, unicellular, smooth-walled, eguttulate (adapted from Sutton 1980, Nag Raj and DiCosmo 1982).
Type species: Rhodosticta caraganae Woron., Izv. Imp. St.-Peterburgsk. Bot. Sada 11: 13 (1911)
Notes: Rhodosticta was re-described and illustrated by Sutton (1980) and Nag Raj and DiCosmo (1982). The sexual morph of Rhodosticta has been assigned to Apiosphaeria Höhn. (Sydow 1930, 1935, Hanlin 1997) and Polystigma DC. (von Höhnel 1917, Sutton 1980, Cannon and Kirk 2007). Dianese et al. (1994) studied the asexual morph of A. guaranitica (Speg.) Höhn. (type species of Apiosphaeria) and stated that Oswaldina icarahyensis Rangel was its asexual morph, rather than R. caraganae. The connection between Rhodosticta and Polystigma has not been successfully demonstrated. Maharachchikumbura et al. (2015) listed Rhodosticta as a member of Chaetosphaeriaceae (Chaetosphaeriales, Sordariomycetes). However, Wijayawardene et al (2017a, 2017b) placed it in Phyllachoraceae (Phyllachorales, Sordariomycetes) and included two taxa. Rhodosticta caraganae has been reported to be associated with leaf lesions on Caragana frutescens (Fabaceae) (Sutton 1980). There is no molecular data available for Rhodosticta. Fresh collections are needed to place it in a natural group.
Distribution: USA (Sutton 1980).
Rhodosticta caraganae (redrawn from Sutton 1980) a Vertical section of conidioma. b Conidia. c Conidiophores, conidiogenous cells and developing conidia.
Li WJ, McKenZie EHC, Liu JK, Bhat DJ, Dai DQ, Caporesi E, Tian Q, Maharachcikumbura SSN, Luo ZL, Shang QJ, Zhang JF, Tangthirasunun N, Karunarathna SC, Xu JC, Hyde KD (2020) Taxonomy and phylogeny of hyaline-spored coelomycetes. Fungal Diversity 100: pages279–801.