Asterina micheligena, 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 : 1944-1945

Asterina micheligena sp. nov.

( Images 6–11 , Fig. 2 )

Materials examined: 20.ix.2008, on leaves of Michelia champaca L. ( Magnoliaceae ), Chennalode, Padinharathara, Wyanad, Kerala, India, coll. M.C. Riju HCIO 49111b (holotype), TBGT 3366b (isotype). MycoBank No. ( MB 561623).

Coloniae epiphyllae, densae, ad 3mm diam., confluentes et saepe et nervicolae. 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, integra, mammiformes, 4–7 x 4–9 µm. Pycnothyria dispersa, orbicularis, ad 75µm diam., stellatim dehiscentes et perlate orificium ad centro; pycnothyriosporae globosae vel leniter ovatae, 17–25 µm diam., parietus glabrus. Thyriothecia dispersa, orbicularis, ad 188µm diam., stellatim dehiscentes et perlate orificium ad centro et asci distinctum; asci globosi vel ovati, ad 63µm diam.; ascosporae brunneae, uniseptatae, constrictus ad septatum, 25–33 x 15–18 µm, parietus glabrus.

Colonies epiphyllous, dense, up to 3mm in diameter, confluent and often trait along the major veins of the upper surface of the leaves. Hyphae substraight to flexuous, branching opposite, alternate to irregular at acute to wide angles, loosely to closely reticulate, cells 9–24 x 4–6 µm. Appressoria scattered, unicellular, opposite, alternate, unilateral, globose, entire, mammiform, 4–7 x 4–9 µm. Pycnothyria scattered, orbicular, up to 75µm in diameter, stellately dehisced and widely opened at the centre; pycnothyriospores

6 - infected leaves; 7 - colony with apressoriate mycelium; 8 - thyriotheca; 9 - asci; 10 - germinating ascospore;

11 - germinating pycnothyriospore

b - thyriothecium;

c - ascus;

d - ascospores;

e - pycnothyriospores

Key to the Asterina species on the genus Michelia

1 Only anamorph known ............................................................................................... Asteostomella micheliae

1 Teleomorph known .......................................................................................................................................... 2

2 Mature fruiting body resembles perithecia ........................................................................... Asterina micheliae

2 Mature fruiting body resembles thyriothecia ................................................................................................... 3

3 Ascospores less than 28µm long ..................................................................... Asterina michelifolia sp. nov.

3 Ascospores more than 28µm long .................................................................................................................. 4

4 Ascospores more than 15µm broad ............................................................... Asterina micheligena sp. nov.

4 Ascospores less than 15µm broad .................................................................................................................. 5

5 On Manglietia .............................................................................................................................. A. manglietiae

5 On Michelia ................................................................................................................................. A. micheliicola

globose to slightly ovate, 17–25 µm in diameter, wall smooth. Thyriothecia scattered, orbicular, up to 188µm in diameter, stellately dehisced and widely opened at the centre by exposing asci; asci globose to ovate, up to 63µm in diameter; ascospores brown, uniseptate,

constricted at the septum, 25–33 x 15–18µm, wall smooth.

Etymology: Specific epithet based on the host genus.

Figures

Figure 2. Asterina micheligena sp. nov. a - apprassoriate mycelium;

Images 6–11. Asterina micheligena sp. nov.