Tremella poilkavensis A. Thomas & T.K.A. Kumar

Thomas, Anjitha & Kumar, T. K. Arun, 2023, A new species of Tremella from India, Phytotaxa 600 (1), pp. 35-42 : 38

Tremella poilkavensis A. Thomas & T.K.A. Kumar Fig.1 : A–P.

MycoBank: 847007

Etymology:—Refers to the collection locality, Poilkave sacred grove.

Diagnosis:— T. poilkavensis differs from other Tremella species by their medium-sized, amber brown to blackish brown basidiocarp, pyriform to capitate basidia, ellipsoid, subcylindrical, subglobose or amygdaliform basidiospores, conidiospores budding off from basidia, growth on ascomata of Biscogniauxia species and presence of host hyphae within the basidiocarp.

Holotype:— INDIA. Kerala State, Kozhikode District, Poilkave sacred grove, on ascomata of a Biscogniauxia sp. growing on dead and decaying wood, 14 July 2021, Anjitha Thomas , ZGCAT243 .

Basidiocarp medium-sized, 55–75 × 7–26 mm, gelatinous to cartilaginous, cerebriform, hollow, sessile, broadly attached to the substratum, amber brown to blackish brown when fresh, turning more blackish when dry. Spore print pale yellow.

Hymenium pale yellow to brownish yellow in water, dikaryophyses absent. Basidia 19–31 × 9–13.3 µm (including stalk), pyriform to capitate, four-celled, oblique or longitudinally septate, cruciate, thick-walled, guttulate, pale yellow to brownish yellow, with basal clamp connection. Stalk of basidia 5–21 × 2.5–4.5 µm. Sterigma 21–38 × 2–3 µm. Basidia budding off subglobose to ellipsoid conidiospores. Basidiospores 6–9.8 × 4–6.2 µm (Q=1.06–1.8 µm, Qm=1.43 µm), ellipsoid, subcylindrical, subglobose or amygdaliform, hyaline, thin-walled, smooth, apiculate, guttulate. Direct germination, secondary spore production and microconidia formation observed. Microconidia 2–3 × 1.5–2 µm, subglobose to ellipsoid. Terminal swollen cells present within the trama, 7.7–13.3 × 4–7.6 µm, broadly fusiform, ellipsoid, lemoniform, oblong, capitate or clavate in shape, sometimes with 1–3 × 1–1.53 µm apical protuberances. Tramal hyphae mixed with host hyphae, 2–4 µm wide, thick-walled, branched, smooth, guttulate, with clamp connections. Haustoria abundantly present throughout the trama, frequently branching, with basal clampconnection, often attached to the host hyphae.

Additional specimens examined:— INDIA. Kerala State, Kozhikode District, Poilkave sacred grove, on ascomata of an unknown host on dead and decaying wood log, 29 August 2018, Anjitha Thomas ZGCAT14 .

Figures

FIGURE 1. A–P: Tremella poilkavensis. A. Basidiocarp growing on host (white arrow); B–G. Swollen cells; H. Basidiospores with microconidia; I & L. Basidia; J. Conidiospores from basidia; K. Cross section showing hymenium, trama; M. Yeast-like microconidia; N. Branched haustoria; O–P. Haustoria attached to the host hyphae.