Anamorphs reported for genus: none Literature: Cain 1956; Malloc

Anamorphs reported for genus: none. Literature: Cain 1956; Malloch and Cain 1972. Type species Phaeotrichum hystricinum Cain & M.E. Barr, Can. J. Bot. 34: 677 (1956). (Fig. 103) Fig. 103 Phaeotrichum hystricinum (from TRTC 4361,

holotype). a Superficial ascomata on host surface. Note the long and black appendages. b Part of peridium. Note the large cells in surface view. c–f Released reddish brown ascospores with hyaline end cells. Note the strongly constricted middle septum. Scale bars: a = 0.5 mm, b–f = 20 μm (Some information for the following description is from Cain 1956) Ascomata 170–280 μm diam., cleistothecial, solitary, or in small groups, superficial, with 15–20 long straight or slightly flexed, thin, black appendages evenly scattered on the surface of the ascomata, 0.5–1 mm long, 15–25 μm wide at base, click here tapering to less than 5 μm at the blunt apex, with few or without septa, globose, black, smooth (Fig. 103a). Peridium thin, carbonaceous-membraneous, 1-layered, composed of dark brown thick-walled cells of textura angularis, cells 8–16 μm diam., cell wall 0.5–1.5 μm thick (data obtained from Cain 1956) (Fig. 103b). Hamathecium not observed. Asci 42–48 × 14–17 μm, 8-spored, bitunicate form not typical, lacking fissitunicate dehiscence, broadly clavate, with a relatively

thick pedicel which is about 18 μm (data obtained from Cain 1956). Ascospores 14–16 × 4–5 μm, 4-seriate, oblong to ellipsoid, hyaline when young, turning reddish brown at maturity, 1-septate, deeply constricted at the septum, each end this website with a subhyaline and broadly rounded germ pore, smooth, readily separating into partspores Adenosine at the septum at maturity (Fig. 103c, d, e and f). Anamorph: none reported. Material examined: CANADA, Ontario, Muskoka, Stoneleigh, on porcupine dung, 18 Aug. 1932, Cain (TRTC 4361, holotype). Note: the ascomata of the specimen are fragile and no asci could be obtained. Notes

Morphology Phaeotrichum was formally established by Cain (1956) to accommodate two new coprophilous fungi, i.e. P. hystricinum and P. circinatum Cain, and P. hystricinum was selected as the generic type. Phaeotrichum is mainly characterized by its coprophilous habitat, superficial cleistothecial ascocarps covered by long hairy appendages, reddish brown 1-septate ascospore with a broadly rounded germ pore at each end, readily breaking into partspores (Cain 1956). According to Cain (1956), Phaeotrichum possesses untypical bitunicate ascus, and the ascospore releasing is described as “simply break down and allow the contents to become free in the cavity of the ascocarp”. This ascospore releasing mechanism is considered as evolutionarily developed compared to those that “discharge the ascospores through an apical pore” (Cain 1956).

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