Cryptosphaeria bathurstensis (K.D.Hyde & Rappaz) Dayarathne & K.D.Hyde, 2020

Dayarathne, Monika C., Wanasinghe, Dhanushka N., Devadatha, B., Abeywickrama, Pranami, G, E. B., Jones, areth, Chomnunti, Putarak, Sarma, V. V., Hyde, Kevin D., Lumyong, Saisamorn, C., Eric H. & Mckenzie, 2020, Modern taxonomic approaches to identifying diatrypaceous fungi from marine habitats, with a novel genus Halocryptovalsa Dayarathne & K. D. Hyde, gen. nov., Cryptogamie, Mycologie 20 (3), pp. 21-67 : 38

Cryptosphaeria bathurstensis (K.D.Hyde & Rappaz) Dayarathne & K.D.Hyde , comb. nov.

( Fig. 7 )

Eutypa bathurstensis K.D.Hyde & Rappaz, Mycological Research 97 (7): 861 (1993).

MYCOBANK. — MB 825271.

FACESOFFUNGI NUMBER. — FoF 04597.

MATERIAL EXAMINED. — Australia, North Queensland, Avicennia sp. , Bathurst Heads , 10.VII.1991, K.D. Hyde (holo-, BRIP [BRIP- 78339 ]).

DISTRIBUTION. — Australia, Bahamas, Egypt, Hong Kong, India, Malaysia, Taiwan, Thailand.

DESCRIPTION

Sexual morph

Stromata. Up to 1-2 cm long, immersed, blackening the wood surface.

Entostroma. Poorly developed, dorsally limited by a black zone binding the stromatic area.

Ascomata. 450-520 × 600-750 µm, spherical to sub-spherical, regularly spaced, submerged in the wood, occasionally deeply buried, long necked, raised, blackening the wood surface.

Ostiole. 100-270 × 120-220 µm, poorly developed or conical, not sulcate.

Peridium. 35-45 µm wide, comprising thin white line under the black hymenium, composed of three layers; a subhymenial layer of hyaline hyphae of textura globosa-angularis mixed with ascogenous elements, a middle layer comprising guttulate hyaline cells, forming a textura globosa, an outermost layer composed of melanized cells interspersed with wood elements, wider near the ostiolar canal.

Hamathecium. Lining the whole cavity.

Paraphyses. Numerous, hyaline, aseptate, persistent.

Asci. 35-40 × 7-10 µm (ẍ = 35.5 × 8 µm, n = 10) (spore bearing part), 8-spored, clavate, J-, long pedicellate.

Ascospores. 6-10 × 2-2.6 µm (ẍ = 8 × 2.2 µm, n = 30), olivebrown, aseptate, allantoid, guttulate.

Asexual morph

Undetermined.

NOTES

Cryptosphaeria bathurstensis (K.D.Hyde & Rappaz) Dayarathne & K.D.Hyde , comb.nov., was first collected on branches of Avicennia located in the upper intertidal region, inundated by seawater for several days each month at Bathurst Heads, northeast Queensland. This (and an unidentified Eutypa and Eutypella ) was the first species of Diatrypaceae collected in such an “unusual habitat” ( Hyde & Rappaz 1993). It is unusual amongst the Diatrypaceae in possessing a thick, hyaline wall under the hymenium ( Hyde & Rappaz 1993). The wall comprised three strata: subhymenial, median, and external layers. Hyde & Rappaz (1993) described the presence of numerous crystals in middle and outermost layers, which were interspersed with the peridium cells, but we did not observe this in our study. Hyde & Rappaz (1993) described the asexual morph of Cryptosphaeria bathurstensis (K.D.Hyde & Rappaz) Dayarathne & K.D.Hyde , comb. nov., as hyaline, filiform conidia in axenic cultures, which were similar to those previously described within the Diatrypaceae ( Glawe & Rogers 1982, 1986; Rappaz 1987). Our morphological studies showed that this species is similar to Cryptosphaeria species, comprises exclusively corticolous species of the Diatrypaceae , with widely effuse and poorly developed stromata that often are covered by the periderm, which is penetrated only by the separately emerging ostioles. Asci are generally spindle-shaped, long-stipitate, with subolivaceous to brown ascospores ( Glawe & Rogers 1984; Rappaz 1987). This species also resembles Halodiatrype species in lacking stromatic tissues and ascospore morphology. However, ascomata of Halodiatrype species are deeply immersed in a darkened pseudostroma while stromata of Cryptosphaeria bathurstensis (K.D.Hyde & Rappaz) Dayarathne & K.D.Hyde , comb. nov., are immersed but blackening the wood surface with a poorly developed entostroma. Cryptosphaeria bathurstensis (K.D.Hyde & Rappaz) Dayarathne & K.D.Hyde , comb. nov., lacks the unique characteristics of Eutypa species, such as welldeveloped stromata, flask-shaped ascomata, scattered evenly in to a single layer just beneath the surface, often prominent sulcate ostioles or ostioles that are distinctly beaked, black, sometimes ornamented with radial furrows and hyaline or yellowish ascospores ( Wehmeyer 1975; Glawe & Rogers 1984). Cryptosphaeria avicenniae Devadatha & V.V.Sarma , sp. nov., grouped with Cryptosphaeria species in our phylogenetic analyses. Considering the above morphological observations and phylogenetic placement of other morphologically related species we transfer Eutypa bathurstensis to the genus Cryptosphaeria .

Figures

FIG. 7. — Cryptosphaeria bathurstensis (K.D.Hyde & Rappaz) Dayarathne & K.D.Hyde,comb.nov.(BRIP 78339 – holotype):A, herbarium material;B, horizontal section through ascostroma; C, appearance of ascostromata on host; D, section through ascoma; E, peridium; F-H, asci; I, paraphyses; J-N, ascospores. Scale bars: B, 500 μm; C, 1000 μm; D, 100 μm; E-H, 20 μm; I, 10 μm; J-N, 5 μm.