Diachea radiata G. Lister & Petch, 1916

Moreno, G., Castillo, A. & Thüs, H., 2024, Critical revision of Physarales and Reticulariales (Myxomycetes) at the Natural History Museum London (BM), Phytotaxa 644 (2), pp. 79-101 : 94-95

publication ID	https://doi.org/ 10.11646/phytotaxa.644.2.1
DOI	https://doi.org/10.5281/zenodo.13357145
persistent identifier	https://treatment.plazi.org/id/2F1A2035-1549-FFBA-B6F2-0D3BAFEAFDEC
treatment provided by	Felipe
scientific name	Diachea radiata G. Lister & Petch
status

Treatment

Diachea radiata G. Lister & Petch View in CoL , in Farquharson & G. Lister (1916: 130).

Lectotype (designated by Lado & Wrigley de Basanta 2018):— NIGERIA. Oyo State: Ibadan , 7º23’N 3º55’E, spring 1915, C.O.Farquharson, B.M. 4002 [ BM001089754 !] GoogleMaps , + two historic slides: B.M. s.n. [ BM 001089137!], COF. 74A [ BM 001089136!], + one freshly prepared slide: [ BM 001247529!]. Isolectotype:— NIGERIA. Oyo State: Ibadan, 7º23’N 3º55’E, spring 1915, C.O. Farquharson, B.M. 3683 [ BM 001089755!]. Syntype:— SRI LANKA (Ceylon). Trincomalee: 8º34’N 81º14’E, on decayed leaves, Sep 1910, E.E. Green, B.M. 4003 [ BM 001089756!].

Farquharson & Lister (1916) described this new species based on material from Sri Lanka and Nigeria, collected on dead leaves and sticks. Lado & Wrigley de Basanta (2018) studied and typified the three specimens preserved in BM. We have seen all three samples, and provide SEM details for the lectotype ( BM 4002) and syntype ( BM 4003).

The species is characterized by its gregarious or crowded sporocarps with a hemispherical to globose shape. They are sessile or rarely shortly stalked. Hypothallus white and extensive. Stalk when present short and with white containing granules of calcium carbonate. Columella white, conical or shortly cylindrical (according to Neubert et al. 1995 “sometimes absent”). Threads of the capillitium radiating from the columella. Spores globose, 8–11µm in diam., warted to spinulose.

It differs from Diachea leucopodia mainly by the shape of the sporotheca (hemispherical to globose in D. radiata , cylindrical in D. leucopodia ), a longer stalk and white plasmodium, while D. radiata has a globular sporotheca, a shorter or no stalk and an orange-yellow plasmodium. The spore dimensions of both species are similar, although there are authors such as Lister (1925) who assign smaller dimensions (7–9 µm) to D. leucopodia .