Fuscoporia sirumalaiensis E. Arumugam, S. Gunaseelan & M. Kaliyaperumal, 2025

Gunaseelan, Sugantha, Kezo, Kezhocuyi, Arumugam, Elangovan, Karunarathna, Samantha C., Fahad Al-Arjani, Al-Bandari, Elgorban, Abdallah M., Kumla, Jaturong, Suwannarach, Nakarin, Chukeatirote, Ekachai & Kaliyaperumal, Malarvizhi, 2025, Three new species of Fuscoporia (Hymenochaetales, Basidiomycota) from southern India revealed by morphological and multigene phylogenetic analyses, MycoKeys 125, pp. 147-166 : 147-166

Fuscoporia sirumalaiensis E. Arumugam, S. Gunaseelan & M. Kaliyaperumal sp. nov.

Fig. 3

Diagnosis.

Morphologically, Fuscoporia sirumalaiensis is unique with a perennial, imbricate to pileate, dimidiate basidiome, smooth to glabrous, concentrically zonate pilear surface, the presence of cystidioles, hymenial setae, and ellipsoidal basidiospores.

Holotype.

India • Tamil Nadu, Dindigul District, Sirumalai ( 10°28'23"N, 78°01'54"E), on hardwood, 31 Dec. 2022, M. Kaliyaperumal, SRM 09 ( holotype MUBL 1106 ). GenBank: PP 390500 ( nrLSU); PQ 098037 ( ITS); PV 638737 ( rpb 2); PV 638741 ( tef 1-α) .

Etymology.

Refers to the type locality “Sirumalai,” India.

Description.

Basidiomes biennial to perennial, imbricate to pileate, sessile, applanate. Pilei dimidiate, projecting up to 5.2 cm long, 7 cm wide, and 2 cm thick near the attachment. Pilear surface dark brown (6 F 7) to greyish brown (6 E 3), smooth to glabrous, concentrically zonate. Margin brown (6 E 8), acute, up to 1 mm. Context light brown (6 D 8) to brown (6 E 8), duplex, 0.4 cm. Pore surface, light brown (6 D 6) to brown (6 E 7). Pores circular, 5–8 per mm. Tubes light brown (6 D 8) to brown (6 E 8), up to 1 cm long, each stratum up to 0.2 cm.

Hyphal system. Hyphal system dimitic; generative hyphae simple septate; tissue darkening but otherwise unchanged in KOH.

Context. Generative hyphae rare, hyaline, thin to slightly thick-walled, branched, frequently septate, 2–5 µm; skeletal hyphae rust-brown, thick-walled with a narrow to wide lumen, unbranched, aseptate, 2.5–5 µm.

Trama. Generative hyphae hyaline, thin to thick-walled, mostly present at dissepiment edges and subhymenium, frequently branched with simple septate, a few are encrusted at dissepiment edges and in the hymenium, 2.5–5.2 µm; skeletal hyphae dominant, yellowish brown, thick-walled with a medium to wide lumen, aseptate, subparallel along the tubes, 2.5–5.6 µm. Hymenial setae subulate to ventricose, indistinctly encrusted, dark brown, 20-45 × 5.2-9 µm. Cystidioles hyaline, fusoid to subulate, infrequent, tapering at the end, 9–28 × 2.5–7.2 µm. Basidioles broadly clavate 6.5–18 × 3.5–6.2 µm. Basidia broadly clavate, hyaline, four sterigmata, 6–17 × 4–6.5 µm. Basidiospores ellipsoid, hyaline, thin-walled, smooth, CB ̄, IKI ̄, (2.8 –) 3.1–3.6 (– 3.8) × (1.8 –) 2.1–2.6 (– 2.8) µm, Q = 1.5, Q range = 1.2–1.6, (n = 30 / 2).

Distribution.

India ( Tamil Nadu).

Additional specimen examined.

India • Tamil Nadu, Dindigul District, Sirumalai ( 10°27'73"N, 78°01'57"E), on hardwood, 31 December 2022, M. Kaliyaperumal, SRM 21. GenBank: PQ 113746 ( nrLSU); PQ 098038 ( ITS); PV 638738 ( rpb 2); PV 638742 ( tef 1-α) .

Notes.

Multigene phylogenetic analyses revealed that Fuscoporia sirumalaiensis forms a sister clade to F. rhabarbarina (83 % ML / 1 BI) within the F. torulosa complex ( Chen et al. 2023 a, b). Fuscoporia sirumalaiensis and F. rhabarbarina are similar only in their concentrically zonate brown basidiomes, but the two species differ greatly in other morphological characteristics such as the size of cystidioles, hymenial setae, and basidiospores ( Dai 2010). The phenetic features of F. sirumalaiensis vary significantly from those of F. callimorpha , F. dhofarensis , and F. licnoides ( Dai 2010; Oliveira and Gibertoni 2023). Fuscoporia sirumalaiensis differs from F. indica in having larger hymenial setae, differences in cystidiole size, and smaller basidiospores ( F. sirumalaiensis (2.8 –) 3.1–3.6 (– 3.8) × (1.8 –) 2.1–2.6 (– 2.8) μm vs. F. indica (3.2 –) 3.5–4.5 (– 4.8) × (2.2 –) 2.5–2.9 (– 3.2) μm) (present study).

Figures

Figure 3. Fuscoporia sirumalaiensis (holotype MUBL 1106). a. Basidiomes; b. Pore surface; c. Transverse section of a basidiome (arrows indicate the stratified tube layers); d. Dissepiment edges and skeletal hyphae; e. Hymenial setae; f. Cystidioles; g. Basidioles; h. Basidia; i. Basidiospores. Scale bars: 2 cm (a – c); 5 μm (d – i).