Genus

Halobyssothecium

Species

obiones

Author

M. Dayarathne, E.B.G. Jones & K.D. Hyde, Mycological Progress (2018)

Class

Dothideomycetes

Order

Pleosporales

Family

Lentitheciaceae, Subclass Pleosporomycetidae

Synonymy: ≡Byssothecium obiones (P. Crouan & H. Crouan) M.E. Barr, Mycotaxon 82: 378 (2002). ≡Passeriniella obiones (P. Crouan & H. Crouan) K.D. Hyde & Mouzouras, Trans Br Mycol Soc 91(1): 183 (1988). ≡Didymosphaeria spartinae Grove, J Bot, Lond 71: 259 (1933). ≡Heptameria obiones (P. Crouan & H. Crouan) Cooke, Grevillea 18 (no. 86): 30 (1889). ≡Leptosphaeria discors Sacc. & Ellis, Michelia 2 (no. 8): 567 (1882). ≡Leptosphaeria obiones (P. Crouan & H. Crouan) Sacc., Syll Fung (Abellini) 2: 24 (1883). ≡Leptosphaeria obiones f. evolutior Grove, J Bot, Lond 71: 281 (1933). ≡Leptosphaeria obiones (P. Crouan & H. Crouan) Sacc., Syll Fung (Abellini) 2: 24 (1883). ≡Metasphaeria discors (Sacc. & Ellis) Sacc., Syll. Fung. (Abellini) 2: 173 (1883). ≡Passeriniella discors (Sacc. & Ellis) Apinis & Chesters, Trans Br. Mycol Soc 47(3): 432 (1964).

Description

Halobyssothecium M. Dayarathne, E.B.G. Jones & K.D. Hyde, Mycol Prog 17(10): 1165 (2018).

Type and marine species:
Halobyssothecium obiones (M.E. Barr) M. Dayarathne, E.B.G. Jones & K.D. Hyde, Mycol Prog 17(10):1165 (2018).
≡Byssothecium obiones (P. Crouan & H. Crouan) M.E. Barr, Mycotaxon 82: 378 (2002).
≡Passeriniella obiones (P. Crouan & H. Crouan) K.D. Hyde & Mouzouras, Trans Br Mycol Soc 91(1): 183 (1988).
≡Didymosphaeria spartinae Grove, J Bot, Lond 71: 259 (1933).
≡Heptameria obiones (P. Crouan & H. Crouan) Cooke, Grevillea 18 (no. 86): 30 (1889).
≡Leptosphaeria discors Sacc. & Ellis, Michelia 2 (no. 8): 567 (1882).
≡Leptosphaeria obiones (P. Crouan & H. Crouan) Sacc., Syll Fung (Abellini) 2: 24 (1883).
≡Leptosphaeria obiones f. evolutior Grove, J Bot, Lond 71: 281 (1933).
≡Leptosphaeria obiones (P. Crouan & H. Crouan) Sacc., Syll Fung (Abellini) 2: 24 (1883).
≡Metasphaeria discors (Sacc. & Ellis) Sacc., Syll. Fung. (Abellini) 2: 173 (1883).
≡Passeriniella discors (Sacc. & Ellis) Apinis & Chesters, Trans Br. Mycol Soc 47(3): 432 (1964).

MycoBank: MB 554757 Facesoﬀungi: 03929

Saprobic on Spartina sp. and other salt marsh halophytes in marine habitats. Sexual morph: Ascomata 360–400 μm high, 340–380 μm diameter, subglobose or ellipsoidal, immersed to semi-immersed, scattered, ostiolate, carbonaceous, dark brown to black, gregarious. Papilla conical, 25–35 μm high, 130–145 μm wide at the apex, composed of several layers of pseudoparenchymatous cells. Peridium 30–45 μm wide, comprising two layers: outer layer of brown pseudoparenchyma; inner layer of elongated, hyaline cells. Pseudoparaphyses 4–6 μm wide, septate, branched. Asci 180–214 × 12–16 μm (x̄= 185.5 × 14 μm, n = 20), 8-spored, clavate to subcylindrical, short pedicellate with an ocular chamber. Ascospores 28–47 × 10–18 μm (x̄= 38.5 × 14 μm, n = 20), versicolored, end cells hyaline, central cells brown, 3-septate, and constricted at the septa, slightly curved. Asexual
morph: Not observed.

The description was based on Dayarathne et al. (2018).

Key references:

Dayarathne, MC, Wanasinghe, DN, Jones, EBG, Chomnunti, P, Hyde, KD (2018). A novel marine genus, Halobyssothecium (Lentitheciaceae) and epitypification of Halobyssothecium obiones comb. nov. Mycol Prog. 17(10): 1161-1171.

Barr ME (2002). Teichosporaceae, another family in the Pleosporales. Mycotaxon 82:373–389.

Hyde KD, Mouzouras R (1988). Passeriniella savoryellopsis sp. nov., a new ascomycete from intertidal mangrove wood. Trans Br Mycol Soc 91(1):179–185.

Grove WB (1933). New or noteworthy fungi. XIII. London J Bot 71:251–259.

Apinis AE, Chesters CGC (1964). Ascomycetes of some salt marshes and sand dunes. Trans Br Mycol Soc 47(3):419–435.

Khashnobish A, Shearer CA (1996). Re-examination of some Leptosphaeria and Phaeosphaeria species, Passeriniella obiones and Melanomma radicans. Mycol Res 100(11): 1341–1354.

Boise J (1983) On Trematosphaeria circinans and Reinstatement of the Genus Byssothecium. Mycologia 75(4):666–669.

Image:

Halobyssothecium obiones (MFLU 18–1075 epitype). a, b Appearance of ascomata on Spartina culms. c Sections of ascomata. d Section through peridium. e Pseudoparaphyses. f–i Asci. j–m Ascospores. Scale bars: b, 200 μm; c, 100 μm, f–i, 50 μm; d, e, j–m, 20 μm.

The figure was taken from Darayathne et al. (2018).

Type & Location:

Other Specimens:

Substratum:

On Spartina sp. culms

Habitat:

Distribution:

Argentina, Iceland, Portugal, Germany, Japan, UK, USA

Pertinent Literature:

Dayarathne, MC, Wanasinghe, DN, Jones, EBG, Chomnunti, P, Hyde, KD (2018). A novel marine genus, Halobyssothecium (Lentitheciaceae) and epitypification of Halobyssothecium obiones comb. nov. Mycol Prog. 17(10): 1161-1171.

Comments:

The new strain of Halobyssothecium obiones (MFLUCC) collected from Spartina sp. shares similar morphological features with previously described strains (Khashnobish and Shearer 1996a, 1996b; Barr 2002). However, the dark pigmented substance encrusting the ascospores after release from the ascus, as reported by Boise (1983) for B. circinans (type), was not seen in the observations of Dayarathne et al. (2018) and by Khashnobish and Shearer (1996a). The holotype of this species was not found so the new strain was designated as the epitype for this taxon. Phylogenetic results showed that B. obiones did not group in the same clade as B. circinans (type) or within families Massarinaceae or Dacampiaceae but, grouped in Lentitheciaceae. Hence, a final analysis was constructed with Lentitheciaceae representatives and strains of B. obiones (08AV2569, 13AV2143, 20AV2566, 27AV2385 and MFLUCC) formed a well-separated (100% ML, 100% MP, 1.00 PP) lineage within Lentitheciaceae. The notes were taken from Dayarathne et al. (2018).

Images

Fig 1