Rhachomyces latellae W.Rossi & M.Leonardi, 2020

Rossi, Walter & Leonardi, Marco, 2020, New Laboulbeniales from China (Ascomycota), Cryptogamie, Mycologie 20 (1), pp. 1-7 : 4

Rhachomyces latellae W.Rossi & M.Leonardi , sp. nov.

( Fig. 2A )

Differs from Rhachomyces girardii Lepesme & G.Temp. ex Santam. by the shape of antheridia and antheridial appendages, the difference between lower and upper appendages, and the lower number of cells forming the main axis of the receptacle.

ETYMOLOGY. — Named after the Italian entomologist Leonardo Latella, who collected one of the host insects of the new species.

MATERIAL EXAMINED. — China. Guizhou, Quianxi County, Honglin Town, cave Oa Tian Guizhou, on an unidentified Carabid beetle, 21.XI.2003, leg. A. Bileddo, (holo-, FI [ FI WR3033 ]); Quianxi County, Honglin Town, Shu Jia Yan Dong (Shu’s House Cave ), GZ/ Qx/21, alt. 1409 m, on an unidentified Carabid beetle, 17.XI.2001, leg. L. Latella (para-, FI [ FI WR3032 ]).

MYCOBANK. — MB 831067.

DESCRIPTION

Axis of the receptacle from almost straight to variably curved, consisting of 11-18 brownish cells gradually increasing in size and becoming paler from below upwards. The sterile appendages are relatively few: the ones born on the lower portion of the axis are long and slender, consisting of dark brown elongate cells, becoming gradually shorter, paler and more robust in the upper portion of the axis; the appendages surrounding the base of the perithecium are distinctly shorter, usually consisting of five cells about twice longer than broad, except for the uppermost cell which is longer and has a tapering hyaline tip. Antheridial appendages very numerous, each consisting of two brownish cells and a terminal antheridium; the lower of the two cells is short and truncate-conical, the upper about trice longer than broad, the antheridium is straight, broadly bottle-shaped, slightly asymmetrical, with a paler neck. Perithecium sessile, pale brownish yellow, with the two transverse septa between the three lower tiers of the wall-cells highlighted by slight elevations, the tip truncate-conical, the apex flattened. Length from foot to perithecial apex 425-525 µm; perithecium 88-142 × 25-44 µm; longest appendage 240 µm. Thalli growing on the hind femurs are much shorter: 270-310 µm from foot to perithecial apex.

REMARKS

Rhachomyces latellae , sp. nov., bears a superficial resemblance in the general habitus with R. girardii , which is parasitic on Aphaenops , spp. ( Carabidae , Trechini), from the Pyrenees (Europe). The latter fungus, however, has a longer receptacle consisting of up to 29 cells, longer and darker antheridial appendages, curved antheridial necks, shorter sterile appendages with an enlarged hyaline terminal portion, appendages surrounding the base of the perithecium not differing from the others ( Santamaría & Faille 2007).

Figures

FIG. 2. — A, Rhachomyces latellae, sp. nov.; B, Rhachomyces spiralis, sp.nov., immature thallus from the elytra; C, Rhachomyces spiralis, sp. nov., mature thallus from the legs; D, E, Rhachomyces toledanoi, sp. nov.; F, Stigmatomyces ferrugineus, sp. nov. Scale bars: 50 µm.