Asterina michelifolia, Hosagoudar & Riju, 2011

Hosagoudar, V. B. & Riju, M. C., 2011, Two new Asterina species on Michelia champaca from Kerala, India, Journal of Threatened Taxa 3 (7), pp. 1942-1946 : 1942-1943

Asterina michelifolia sp. nov.

( Images 1–5, Fig. 1 )

Materials examined:

20.ix.2008, on leaves of Michelia champaca L. ( Magnoliaceae ), Chennalode, Padinharathara, Wyanad, Kerala, India, coll. M.C. Riju, HCIO 49111a (holotype), TBGT 3366a (isotype). MycoBank No. ( MB 561622).

Coloniae hypophyllae, tenues, ad 2mm diam., confluentes. Hyphae flexuosae vel anfractuae, irregulariter acuteque vel laxe ramosae, formans retes arte reticulatae, cellulae 12–40 x 3–5 µm. Appressoria dispersa, unicellularis, opposita, alternata, unilateralis, antrorsa vel retrorsa, globosa vel cylindracea, integra, 5–18 x 5–8 µm. Pycnothyria dispersa, orbicularis, ad 58µm diam., stellatim dehiscentes et perlate orificium ad centro; pycnothyriosporae globosae, clavatae, 15–20 µm, parietus glabrus. Thyriothecia dispersa, orbicularis, ad 85µm diam., stellatim dehiscentes et perlate orificium ad centro et asci distinctum; asci globosi vel ovati, 37–45 µm diam.; ascosporae brunnneae, uniseptatae, constrictus ad septatum, 22– 25 x 10–13 µm, parietus glabrus.

Colonies hypophyllous, thin, up to 2mm in diameter, confluent. Hyphae flexuous to crooked, branching irregular at acute to wide angles, forming closely reticulated rings, cells 12–40 x 3–5 µm. Appressoria scattered, unicellular, opposite, alternate, unilateral, antrorse to retrorse, globose to cylindrical, entire, 5–18 x 5–8 µm. Pycnothyria scattered, orbicular, up to 58µm in diameter, stellately dehisced and widely opened at the centre; pycnothyriospores globose, clavate, 15–20 µm, wall smooth. Thyriothecia scattered, orbicular, up to 85µm in diameter, stellately dehisced and widely opened at the centre by exposing asci; asci globose to ovate, 37–45 µm in diameter; ascospores brown, uniseptate, constricted at the septum, 22–25 x 10–13 µm, wall smooth.

Etymology: Specific epithet based on the host genus.

This species differs from Asterina micheliae Hansf. reported on Michelia nilagirica from Sri Lanka ( Hansford 1947) in having typical thyriothecium and differs from A. micheligena in having straight mycelium and larger ascospores.

b - thyriothecium;

c - ascus; d - ascospores;

e - pycnothyriospores

1 - infected leaf;

2 - colony with thyriothecia;

3 - thyriothecium;

4 - asci;

5 - germinating ascospore

Figures

Figure 1. Asterina michelifolia sp. nov. a - apprassoriate mycelium;