Fungalpedia – Note 1065, Halotestudina

 

Halotestudina. Dayar. & K.D. Hyde.

Citation when using this data: Dayarathne MC et al. 2020 (in prep.) – Fungalpedia, Ascomycota.

Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig 1

Classification: Testudinaceae, Incertae sedis, Dothideomycetidae, Dothideomycetes, Pezizomycotina, AscomycotaFungi

Saprobic on mangrove wood. Sexual morph: Ascomata subglobose, completely or partially immersed, carbonaceous to coriaceous, black, gregarious, ostiolate. Peridium coriaceous to carbonaceous, two-layered, outer layer composed of elongate cells, inner layer composed of smaller hyaline cells. Hamathecium comprising trabeculate pseudoparaphyses, unbranched at the base, anastomosing above the asci, embedded in a gelatinous matrix. Asci 8-spored, bitunicate, fissitunicate, cylindrical, long-pedicellate, with a refractive non-amyloid, apical ring. Ascospores biseriate, ellipsoidal to broadly fusiform, muriform, pale brown to brown, with hyaline to pale brown apical cells, glabrous, with a gelatinous cap or a mucilaginous sheath. Asexual morph: Unknown.

Notes – Halotestudina can be easily distinguish from other Testudinaceae genera by its brown muriform ascospores that are constricted at each septum. The genus Muritestudina resembles Halotestudina by having muriform ascospores but it can be clearly distinguished as it has hyaline ascospores surrounded by a thick, mucilaginous sheath (Wanasinghe et al. 2017). Verruculina is clearly different form Halotestudina in ascospore morphology which are 1-septate, while ascospores of Halotestudina are muriform. In our phylogenetic analyses they formed a moderately-supported (73% ML) clade. Halotestudina and Verruculina are two marine genera referred to Testudinaceae. Halotestudina shows a close phylogenetic placement to the genera Trematosphaeria and the Angustospora. Trematosphaeria species are different form Halotestudina in having a trabeculate hamathecium embedded in a gelatinous matrix and reddish-brown ellipsoid to fusoid transversely septate ascospores sometimes with paler end cells (Boise 1985, Barr 1990b, Mckeown et al. 2001). Angustospora is morphologically quite different from Halotestudina in having large ascospores with a median septum and additional septa near the poles of the ascospores (Li et al. 2016). 

Type species: Halotestudina muriformis Dayar. & K.D. Hyde, in Dayarathne, Jones, Maharachchikumbura, Devadatha, Sarma, Khongphinitbunjong, Chomnunti & Hyde, Mycosphere 11(1): 69 (2020).

Other accepted species: Species Fungorum – search Halotestudina.

 

image

 

Figure 1 – Halotestudina muriformis (MFLU 17-2634, holotype). a Ascoma on host surface. b Section of ascoma. c Peridium. d, e Asci and pseudoparaphyses. f–h Immature and mature ascospores. s Germinating ascospore. n, o Cultures on sea water PDA (n-upper, o lower). Scale bars: a, b = 200 μm, d, e = 100 μm, c = 50 μm, f–i = 20 μm.

 

References

Barr ME 1990b – Some dictyosporous genera and species of Pleosporales in North America. Memoirs of the New York Botanical Garden 62, 1–92.

Boise J. 1985 – An amended description of Trematosphaeria. Mycologia 77, 230–237.

Li S, Liu C, Huang J, Liu Y et al. 2016 – Transcriptome and biomineralization responses of the pearl oyster Pinctada fucata to elevated CO2 and temperature. Scientific Reports 6, 18493.

Mckeown TA, Alias SA, Moss ST, Jones EBG. 2001 – Ultrastructural studies of Trematosphaeria malaysiana sp. nov. and Leptosphaeria pelagica. Mycological Research 105, 615–624.

Wanasinghe DN, Hyde KD, Jeewon R, Crous PW et al. 2017 – Phylogenetic revision of Camarosporium Pleosporineae, Dothideomycetes and allied genera. Studies in Mycology 87, 207–256

 

Entry by

Monika Dayarathne, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand, School of Science, Mae Fah Luang University, Chiang Rai57100, Thailand, World Agro forestry Centre East and Central Asia Office, 132 Lanhei Road, Kunming 650201, China, Key Laboratory for Plant Biodiversity and Biogeography of East Asia (KLPB), Kunming Institute of Botany, Chinese Academy of Science, Kunming 650201, Yunnan, China

 

Published online 13 January 2020