Erioscyphella papillaris Tochihara, 2022

Tochihara, Yukito & Hosoya, Tsuyoshi, 2022, Examination of the generic concept and species boundaries of the genus Erioscyphella (Lachnaceae, Helotiales, Ascomycota) with the proposal of new species and new combinations based on the Japanese materials, MycoKeys 87, pp. 1-52 : 1

Erioscyphella papillaris Tochihara sp. nov.

Figs 11 , 12

Diagnosis.

Characterized by protruding papillary hairs with hyaline apical amorphous materials.

Holotype.

Japan, Gunma, Minakami, Yubiso, Mt. Tanigawadake, 36.064014, 141.344653, ca 710 m, 16 Jul. 2017, on both sides of a fallen leaf of bamboo, Y.Tochihara (TNS-F-81272).

GenBank/UNITE no. ex holotype.

LC669473/UDB0779085 (ITS), LC533161 (LSU), LC533285 (mtSSU), LC533204 (RPB2).

Etymology.

Referring to papillate hair apices.

Japanese name.

Sasaba-hina-no-chawantake.

Description.

Apothecia gregarious, superficial, minute, 0.1-0.3 mm in diameter, short-stipitate, up to 0.25 mm high, externally densely covered with pure white short hairs. Disc concave, white to lemon yellow when fresh and dry. Ectal excipulum textura prismatica composed of cuboid cells, 3-13 × 2.5-7 µm, hyaline, thin-walled, lacking carotenoid pigments; cell walls smooth. Medullary excipulum textura intricata of hyaline hyphae up to 3 µm wide. Hairs straight, cylindrical, 45-75 × 3-5 µm, 2-3-septate, hyaline, totally granulate, thin-walled, arising from swollen cells; apical cells rather longer than other cells, 30-40 µm long, with papillate at the apex, sometimes swelling, equipped with hyaline and globose apical amorphous materials not dissolved with CB/LA, lacking any crystals or resinous matters. Asci (59-)59.8-66(-69) × (7.5-)7.6-8.3(-9) µm (av. 63 ± 2.9 × 8.0 ± 0.4 µm, n = 16), 8-spored, cylindrical-clavate; pore inamyloid with MLZ without 3% KOH pretreatment, faint blue with MLZ with 3% KOH pretreatment, dark blue with IKI with and without KOH pretreatment; vesicle apparatus inverted-v-shaped present near the apices; croziers absent at the basal septa; base sympodially branched. Ascospores (16-)17.5-21.7(-24) × (2-)2.3-2.8(-3) µm (av. 20 ± 2.1 × 2.6 ± 0.3 µm, n = 20), Q = (6.4-)6.8-8.9(-9.8) (av. 7.8 ± 1.0, n = 20), fusiform, aseptate, or one-septate (rarely two-septate), filled with hyaline oil drops. Paraphyses straight, cylindrical, up to 3 µm wide, septate, containing small hyaline lipid bodies, equal or scarcely exceeding the asci.

Culture characteristics.

Colony of NBRC 113937/ TNS-F-81272 on PDA divided into two semicircular zones. The first zone umbonate, pruinose, white, producing white aerial mycelia densely, presenting wooly appearance; margin distinct, entire, flat. The second zone flat, glutinous, white to beige with concentric patterns, producing few aerial mycelia; margin entire, flat and immersed into agar, irregularly undulate. The reverse uniform unrelated to the zoning position, beige to pale dark brown throughout. Soluble pigment and asexual morph absent throughout the colony.

Distribution.

Japan (Mt. Tanigawa). Currently known only from the type locality.

Notes.

This species is similar to Lachnum sclerotii var. microascum in the dimension and shape of asci and ascospores, habitats, and inconspicuous ascus apex reaction in MLZ ( Zhuang 2004). However, E. papillaris has ascospores containing conspicuous guttules in any mount (Fig. 11G ) and filiform paraphyses rarely exceeding the asci (Fig. 11F , Fig. 12D , and Fig. 12G ), whereas L. sclerotii var. microascum has non-guttulate asci and narrowly lanceolate to lanceolate paraphyses exceeding the asci by 15-18 µm ( Zhuang 2004). Although DNA sequences of L. sclerotii var. microascum are not available, we judged the present fungus as different from it, because the presence or absence of guttules in ascospores is a significant taxonomic character at the species level ( Baral 2015).

Papillate hairs are also shown in the line drawings of Lachnum gahniae Spooner ( Spooner 1987), suggesting the relationship of the present fungus to Australasian species. However, L. gahniae can be distinguished by having longer hairs, occurring on different substrates (leaves of Cyperaceae ) and showing different ascal-iodine reactions (MLZ+) ( Spooner 1987), although DNA sequences of L. gahnia are not available.

Figures

Figure 11. Erioscyphella papillaris TNS-F- 81272 (Holotype) A dried apothecia B pure culture on PDA (NBRC 113937) C Ascus arising from ascogenous hyphae D an ascus E ascal pore iodine reactions E 1 MLZ (-) without 3 % KOH pretreatment E 2 MLZ (-) with 3 % KOH pretreatment E 3 IKI (+) without 3 % KOH pretreatment F paraphysis G ascospores with guttules H ectal excipulum I hair-apex with a apical amorphous material J hairs. Mounted in CB / LA (C, D, F-J), MLZ (E 1, E 2), IKI (E 3). Scale bars: 0.5 mm (A); 10 µm (C-J).

Figure 12. Erioscyphella papillaris TNS-F- 81272 (Holotype) A apothecium B vertical section of an apothecium C ascospores D expansion of an vertical section of an apothecium E ectal excipular cells F asci G paraphyses H hairs with cap-like structures.