Pseudozeugandromyces tachypori De Kesel & Haelew., sp. nov. – Fig. 21

MycoBank number: MB 835915; Index Fungorum number: IF 835915; Facesoffungi number: FoF;

Holotypus . – BELGIUM. West Flanders Province, Knokke-Heist, Nature reserve Het Zwin, on Tachyporus pusillus Gravenhorst, 1806 (Coleoptera, Staphylinidae, Tachyporinae, Tachyporini), ADK658 [host label], 17 July 1992, leg. G. Haeghebaert, slide BR5020212154341V (2 thalli from abdomen; holotype).

Description. – Thallus 229–290 μm, amber in color. – R e c e p t a c l e 70–83 μm high, its axis composed  of  superposed  cells  I, II, and  III. – C e l l I 25–35 μm high, 2–3× higher than broad, widest above. – C e l l I I 25–35 μm high, up to 2× higher than broad, pentagonal, apically supporting cells III and VI. – C e l l I I I 12–18 μm high, isodiametrical, apically carrying the primary appendage.

– P r i m a r y a p p e n d a g e up to 80 μm long; com- posed of a single, dark basal cell of 9–10 × 8–10 μm, carrying two simple antheridial branches at the apex. – Antheridial branches simple, very thin, hyaline to amber, composed of a series of 4–6 single, intercalary antheridia with bent and later- ally extending necks. – C e l l V I 30–40 μm high, 2× higher than broad, free, apically supporting cells VII and m. – C e l l s V I I a n d V I together measuring 50–80 μm high. – C e l l s V I I a n d m of similar height, both higher than broad, laterally connected and frequently kinked in dorsal (posterior) direction. – P e r i t h e c i u m 135–173 × 55–88 μm, asymmetrical, with venter, widest in the middle, gradually tapering upwards, apex slightly curved in anterior direction, wall cells of unequal height; apex relatively broad and round, with very similar and poorly differentiated ostiolar lips. – A s c o s p o r e s 42 × 5.0 μm.

Etymology. – Named after the host on which the fungus was found.

Hosts and distribution. – Thus far only known on Tachyporus pusillus in Belgium.

Additional material examined. – BELGIUM. West Flanders Province, Knokke-Heist, Nature reserve Het Zwin, on Tachyporus pusillus, ADK656 [host label], 19 June 1992, leg. G. Haeghebaert, slides BR5020212153313V (4 thalli from left protrochanter) and BR5020212152286V (1 thallus from left procoxa); Ibid., on T. pusillus, ADK1682 [host label], 12 April 1992, leg. G. Haeghebaert, slides BR5020212151258V (3 thalli from metathorax) and BR5020212150220V (3 thalli from metathorax).

Notes . – Since 2010, three new genera of Laboulbeniales have been described (Rossi & Santamaría 2012, Santamaría et  al. 2017, Reboleira  et al. 2018). These are Opilionomyces Santam., Enghoff, Gruber & Reboleira from harvestmen (Opiliones, Dicranolasmatidae), Rodaucea W. Rossi & Santam. from cholevine beetles (Coleoptera, Leiodidae), and Thaxterimyces Santam., Reboleira & Enghoff from millipedes (Chordeumatida, Metopidiotrichidae). Elsewhere in this paper, we reinstate Appendiculina Berl. and Fanniomyces T. Majewski, bringing the number of accepted genera in the or- der to 144. Here, we introduce another new genus, Pseudozeugandromyces, to accommodate a species that we long thought of as a member of Zeugandromyces Thaxt. (De Kesel 1997).

Fig. 21. Pseudozeugandromyces tachypori from Tachyporus pusillus. a. Mature thallus from abdomen, slide BR5020212154341V (holotype). b. Mature thallus from abdomen, slide BR5020212154341V (holotype). c. Mature thallus from left protrochanter, slide BR5020212153313V. d. Mature thallus from left procoxa, slide BR5020212152286V. e. Mature thallus from metathorax, slide BR5020212151258V. Scale bar 50 μm, del. A. De Kesel.