Asteridiella elaeocarpicola var. gadgilii A. Sabeena & H. Biju, 2022

Sabeena, Aliyarukunju & Biju, Haridas, 2022, A new species and a new variety of Meliolaceae fungi from India, Phytotaxa 541 (1), pp. 57-65 : 62

Asteridiella elaeocarpicola var. gadgilii A. Sabeena & H. Biju var. nov. ( Figs 3 , 4 )

MycoBank No.: MB 842474

Type:— INDIA. Kerala: Thiruvananthapuram, Ponmudi , on leaves of Elaeocarpus gadgili Maya et al. (Elaeocarpaceae) , 25 August 2021, Sabeena & Biju, 7117 (holotype TBGT!) ; Ponmudi, 9 October 2020, Sabeena & Biju 7118 (paratype TBGT!).

Etymology:— The new taxon is named after its host species.

Colonies epiphyllous, thin to sub-dense, up to 2 mm in diameter, confluent. Hyphae straight to flexuous, branching opposite at acute to wide angles, loosely reticulate, cells 25–40 × 5 μm. Appressoria alternate to opposite, antrorse to subantrorse, straight to curved, 12–17 μm long; stalk cells cylindrical to cuneate, 2.5–5 μm long; head cells globose, oblong, truncate, entire, 10–12 × 7–10 μm. Phialides mixed with appressoria, opposite to unilateral, ampulliform, 12.5– 20 × 5–10 μm. Perithecia scattered, up to 170 μm in diameter; perithecial wall cells prominent, conoid, mammiform, attenuated, straight to curved at the tip, up to 37 μm long; ascospores oblong to ellipsoidal, 4-septate, constricted at the septa, 42–47 × 15–17 μm.

Notes:— Amazonia elaeocarpi Hosag. et al. , Appendiculella elaeocarpi Hosag. & P.J. Robin , Asteridiella elaeocarpi-tuberculati Hosag. , Asteridiella elaeocarpicola Hansf. , Meliola elaeocarpi H.S. Yates and Meliola elaeocarpicola Lini K. Mathew ( Table 2) are the known meliolaceous fungi occurring on the host genus Elaeocarpus ( Hosagoudar 1996, 2008, 2013, Hosagoudar et al. 1997, Hosagoudar & Agarwal 2008, Hansford 1961, Yates 1917, Mathew&Thomas 2020).The new taxon differs from Asteridiella elaeocarpicola in the presence of alternate and opposite appressoria and comparatively smaller ascospores, whereas Asteridiella elaeocarpicola has only alternate appressoria and larger ascospores. The Beeli formula of present taxon is 3103.4222 whereas in Asteridiella elaeocarpicola , it is 3101.6320. The other reported Asteridiella species, A. elaeocarpi-tuberculati clearly shows differentiation in having alternate appressoria and phialides borne on a separate mycelial branch.

Figures

FIGURE 3. Asteridiella elaeocarpicola var. gadgilii. a. Appressorium. b. Phialide. c. Perithecial wall cells. d. Ascospores. Illustrator: Aliyarukunju Sabeena.

FIGURE 4. 1. Infected leaves of Elaeocarpus gadgilii. 2. Colony with perithecia. 3, 4. Appressoriate mycelium. 5. Hyphae showing phialides mixed with appressoria. 6. Mature perithecium. 7, 8. Ascospores. Photographer: Haridas Biju.