Rhachomyces cruralis W. Rossi & M. Leonardi, sp. nov.
Index Fungorum number: IF 559505; MycoBank number: MB 559505; Facesoffungi number: FoF 13385; Fig. 1
Etymology – From Latin crus=leg, because the thalli of the new species are found only on the legs of the host insect.
Holotype – FI WR1997
Axis of the receptacle is straight or slightly curved, consisting of 10–15 brownish cells gradually increasing in size and bearing a dark brown band in the lower portion. Appendages almost straight, more numerous in the upper portion of the thallus, usually consisting of 5–6 dark brown cells separated by back septa and slight constriction, the distal one being distinctly longer and gradually paler, with the lower portion slightly inflated and the tip hyaline or almost so. Antheridial appendages very few, consisting of a short and brownish lower cell followed by a straight hyaline antheridium. Perithecium reddish-brown, subsessile, symmetrically elliptical, about twice as long as it is broad, regularly tapering to the darker, subconical tip and almost hyaline, rounded apex. Length from foot to perithecial apex 270–350 µm. Perithecium, including basal cells 125–175 × 60–80 µm. Longest appendages 100 µm.
Material examined – South Africa, E Transvaal, Mt. Sheba Nat. Res., 14–15.II.1995, S. Zoia, on posterior legs of Pachydesus rufipes (Boheman) (Carabidae, Trechini) (FI WR1997, holotype). Same data as the type, M. Zapparoli
legit (FI WR1987 and WR 2000, paratypes); same data as the type, A. Vigna Taglianti legit, FI WR1998 and WR1999, paratypes).
Notes – The species is more similar to Rhachomyces cruralis and R. moreti W. Rossi et Proaño, parasitic on Trechisibus calathiformis Deuve from Ecuador. The latter fungus, however, has an oblong perithecium, the axis of
the receptacle consists of 16–18 cells, and the appendages are paler and slenderer (Rossi and Proaño Castro 2009).
Figure 1 – Rhachomyces cruralis (FI WR1997, holotype). Scale bar=50 µm