Lentinus badius

Lentinus badius (Berk.) Berk.

Index Fungorum number: IF473358; Facesoffungi number: FoF 14089

Pileus 20–33 mm diam., convex when young with slightly depressed center, expanding to plano–convex to infundibuliform with depressed center, with inflexed to involved margin; background viscid and shiny when wet, smooth or glabrous when dried, with long striate margin, 8–10 mm long, greyish brown to brown (7E3–5) when young, lighter when mature, brownish orange to brown (6C4–6, 6D6–7), dark brown at center (6F7–8), covered with light brown to brown (6D4–6, 6E6–7) large warts at center toward margin; with white to light brown (6D4–6) warts at margin. Lamellae subdecurrent, white to orange–white (5A2–3), turned to greyish orange (5B3–4) with age, ventricose and wider at middle, smooth edge, furcate, with 2 branched levels, glutinous and solid when dry. Stipe central, 22 × 4–5 mm, cylindrical, with white fibrillose background, turned light brown (6D4–6) with age, covered concolorous warts same as pileus. Annulus with, membranous with split margin, attached at base zone of lamellae attachment. Context white at pileus and stipe, fleshy–tough to leathery, turned brown and solid when dried. Oder and Taste not observed. Spore print white. Hyphal system at tramal structure dimitic with generative hyphae and skeletal–ligative hyphae; generative hyphae thick–walled, hyaline, with clamp connection, 4–6 µm wide, cylindrical to irregular cylindrical; skeletal–ligative hyphae thick–walled, hyaline, up to 8 µm wide, very long with 3–6 branches. Hyphae of scale on pileus irregular epithelium to hymenoderm made up of arranged elongate, short clavate, clavate, sub–clavate, sub–globose, globose elements, 13–25 × 5– 15 µm, slightly thick–walled, pale brown, branched. Basidiospores 5.5–6.8 × 2.8–3.2 µm, smooth, oblong to cylindrical, slightly thin–walled, hyaline, non–dextrinoid. Basidia clavate, 20–25 × 5–7.5 µm, thin–walled, hyaline, 4–spored. Cheilocystidia absent. Pleurocystidia abundant, clustered, composed of several cylindrical to nettle hair–shaped, 50–90 × 3–10 µm, mostly wider or swollen at base zone (up to 12 µm wide) and tick–walled, cylindrical, or attenuate to apex (3–4 µm wide) and thin–walled, hyaline.

Habitat and distribution: Solitary, grows on dead wood, in wet rain forests with large trees and wet forest ground.

Material examined: Thailand; Krabi Province, Ao Luek District, Khlong Ya, 09 January 2020, P. Sysouphanthong, PS2020–20 (MFLU22–0029); Chiang Mai Province, Mae Kam Pong, 23 August 2019. P. Sysouphanthong, PS2019–85 (MFLU22–0028).

Notes: During our mushroom surveys of in Thailand, a single fruiting body was found in two collections was found; MFLU22–0028 was collected from Chiang Mai, northern Thailand, in a young stage without basidiospore production; and MFLU22–0029 was collected from Krabi, south Thailand, in a mature stage, from which the main description and ITS sequences were received from this species. However, Lentinus badius was reported from a dense humid forest in northern Thailand with abundant fruit bodies on rotten wood by Høiland & Schumacher (1982). Seelan et al. (2015) reported L. badius from central (Nakhon Ratchasima) and southern (Phuket) Thailand. Lentinus badius is the only species in the sect. Dicholamellatae Pegler (Seelan et al. 2015), and was described from Sri Lanka by Berkeley (1847) based on macromorphology only, and a comprehensive description was absent in later studies. Available molecular data of L. badius are from tropical countries such as India, Indonesia, Malaysia, and Thailand (Seelan et al. 2015). A specimen of L. badius from this study clustered well with samples from those tropical countries (Fig. 1). Lentinus badius was also recorded from Brazil with smaller basidiospores (3.75–4.25 × 1.75–2 µm) (Baltazar & Gibertoni 2009, Drechsler–Santos et al. 2008). According to available literature, Lentinus badius was only recorded in a checklist, and described based on macro–characters in Thailand. Here, we redescribe L. badius with morphology and molecular data, and its distribution in Thailand.

Fig. 1 Maximum likelihood tree of Lentinus based on ITS–LSU sequences. The taxa in blue are specimens from Thailand. Support values of ML and MP≥70% and BI ≥ 0.95 are indicated on the nodes. Specimen voucher numbers are indicated after species names. Ganoderma boninense Pat. was used as the outgroup.

Fig. 2 Macrocharacters of Lentinus badius. a–d MFLU22–0029 (mature). e–f MFLU22–0028 (young)