Acervus epispartius (Berk. & Broome) Pfister, Occasional Papers, 1975

Lin, Jia Y., Liu, Zhen-Chao, Li, Guang-Mei, Yang, Zhu L. & Yang, Kun L., 2025, Three new species of Acervus (Ascomycota, Pezizales) from South China, Phytotaxa 700 (1), pp. 73-86 : 82

Acervus epispartius (Berk. & Broome) Pfister, Occasional Papers of the Farlow Herbarium of Cryptogamic Botany

8: 3 (1975)

≡ Peziza epispartia Berk. & Broome , Journal of the Linnean Society, Botany 14(74): 103 (1873) (≡ Phialea epispartia (Berk. & Broome) Pat. , Bulletin de la Société Mycologique de France 29: 221 (1913); ≡ Phaedropezia epispartia (Berk. & Broome) Le Gal, Les Discomycètes de Madagascar: 181 (1953)).

= Acervus aurantiacus Kanouse, Papers of the Michigan Academy of Sciences 23: 149 (1938).

= Peziza flavotingens Berk. & Broome , Journal of the Linnean Society, Botany 14(74): 104 (1873) (≡ Humaria flavotingens (Berk. & Broome) Sacc., Sylloge Fungorum 8: 129 (1889); ≡ Phaedropezia flavotingens (Berk. & Broome) Le Gal , Bulletin du Jardin Botanique de l'État à Bruxelles 29(2): 96 (1959)).

= Peziza radiculosa Berk. & Broome , Journal of the Linnean Society, Botany 14(74): 103 (1873) (≡ Sarcoscypha radiculosa (Berk. & Broome) Sacc., Sylloge Fungorum 8: 155 (1889)).

= Peziza microspora Berk. & M.A. Curtis , Grevillea 3(28): 150 (1875) (≡ Humaria microspora (Berk. & M.A. Curtis) Sacc., Sylloge Fungorum 8: 131 (1889)).

Description: — Ascomata tiny to small, sessile, at first globular and top-flattened with an indented ring-like structure, then the indented ring separating from the surrounding material by the expansion of apothecium and resulting in a flap-like tissue attached to the edge of apothecium or fallen off. Apothecium 7.5–10.5 mm broad, 2–3.5 mm high, cupulate to nearly plane, with an often ruptured margin when mature, arising from a yellowish mycelial pad. Hymenium surface smooth, autumn orange (#F5C040), honey orange (#FFAC2A) to dark persimmon orange (#EC8D32) when fresh, becoming deer orange (# E69754 ) after dried. External surface relatively rough, yolk orange (#FEDC3D) to sun orange (#FCD742) when fresh, becoming walnut orange (#E9C680) to curry orange (#CDA546) after dried. Context fragile, yellowish to orangish. Odour indistinct. Taste unknown.

Ascospores ellipsoid to oblong, uniseriate, nearly colourless, thin- to slightly thick-walled, non-septate, smooth, {40/2/2} 6–7 (7.5) [6.63 ± 0.38, 6.50] × 3.5–4.5 [3.84 ± 0.30, 4.00] µm, Q = 1.44–2.00 [1.73 ± 0.13, 1.75] including spore wall, uniguttulate. Asci narrowly cylindrical, operculate, eight-spored, nearly colourless, 75–120 µm in length, with a sporiferous part 41–48 × 6–8 µm when mature, with a crozier at the base. Paraphyses abundant, filiform, yellowish, 4.5–7 µm wide at the middle, septate, unbranched to frequently branched. Subhymenium up to 25.5 µm thick, slightly yellowish to yellowish. Medullary excipulum up to 415 µm thick, composed of a gelatinized textura intricata of yellowish, 6.5–20 µm wide, thick-walled hyphae. Ectal excipulum up to 185 µm thick, composed of a slightly gelatinized textura globulosa, textura angularis to textura epidermoidea of slightly yellowish to yellowish, 10.5–50 × 10–30 µm, thin-walled cells, with abundant hyphae up to 7.5 µm wide at the middle arising from the external surface.

Habitat and distribution: —Gregarious, on soil in the field or in mushroom cultivation farms. Currently known from Africa ( Benin: GenBank No. PQ528032 (nrLSU)), Asia ( China), Europe ( Italy) and North America ( USA) with molecular evidence.

Collections examined: — CHINA. Yunnan Province: Kunming City, Kunming Botanical Garden , on soil, 25°08'33"N, 102°44'26"E, elevation 1975 m, August 28, 2020, Zhu L. Yang, HKAS112794 ; same location, October 12, 2023, Zhu L. Yang, HKAS131151 ; same location, August 18, 2024, Kun L. Yang, K24072 ( HTBM2087 (nrLSU: PV168191; rpb2: PV172438; tef-1α: PV172442 )) .

Notes: —Although a form, namely Acervus epispartius f. albus , has been reported within this species, A. epispartius f. epispartius has vividly coloured ascomata, larger ascospores, longer and wider asci and wider paraphyses, suggesting that these two taxa may actually represent two independent species.