Key 2. Perithecial, pseudothecial, cleistothecial and gymnothecial fungi

1
(key 1,2)
Perithecia occurring singly or in groups, but directly on the dung or buried in it (figs 16, 28, 19, 22, 27, 30, 32, 34-36). 2
- Perithecia occurring in or on a mass of fungal tissue (stroma) growing in or on the dung (figs 32, 37). 135
2(1) Spores black, brown or dark olive-greenish. 3
- Spores hyaline or pale coloured, at least under the microscope (may be coppery red en masse). 117
3(2) Spores smooth, without an ornamentation of hyaline pits. 4
- Spores 1-celled, ornamented with hyaline pits.
(Gelasinospora) 114
4(3) Perithecia dark, olive, brown or black. 5
- Perithecia reddish brown, orange or golden, globose, with a neck. Spores black, limoniform. 116
5(4) Perithecia globose, surmounted by a dense tuft of greyish green hairs, which may be branched or simple, straight or curly. Spores olivaceous, limoniform. Asci clavate, soon disappearing. (A large genus not characteristic of dung, but occurring occasionally).
Chaetomium (fig. 16)
- Perithecia more pyriform, or if globose then with a distinct neck, may be setose but not densely hairy, with clavate or cylindrical asci. 6
6(5) Each spore composed of 4 or more cells in a row (figs 17, 21). Asci bitunicate (figs 20, 23). 7
- Spores 1- or 2-celled. Asci bitunicate or unitunicate. 29
7(6) Spores 16-32-celled, united firmly together in a bundle both in the ascus and after discharge. Germ slits usually absent.
(Sporormia) 8
- Spores each with 4 or more cells, each spore free and surrounded by its own gelatinous sheath. Germ slits usually present.
(Sporormiella) 11
8(7) Spores 16-20-celled. 9
-
Spores 29-32-celled, 130-160 × 4-6µm. Sporormia mirabilis
9(8)
Spores 16-celled, 85-116 × 5-6.5µm. Sporormia fimicola
- Spores smaller. 10
10(9) Spores 16-celled, 37-45 × 3µm. Asci 50-60 × 10-12µm.
Sporormia sp. (fig. 17)
[recorded as S. fimetaria by Richardson (1972); see also Bell (1983) and Dissing (1992)]
- Spores 16-20-celled, 50-57 × 3.5-4.5µm. Asci 70-80 × 12-16µm.
Sporormia fimetaria
(These two taxa may represent the extremes of S. fimetaria).
11(7) Spores 4-celled. 12
- Spores more than 4-celled. 22
12(11) Spores more than 65-70µm long. 13
- Spores less than 65-70µm long. 15
Figures 16-21

Fig. 16. Chaetomium sp., perithecium and spore.
Fig. 17. Sporormia sp., ascus and spores.
Fig. 18. Sporormiella ovina, pseudothecium.
Fig. 19. S. intermedia, pseudothecium.
Fig. 20. S. intermedia, immature bitunicate ascus and mature ascus with outer layer ruptured.
Fig. 21. Ascospores of, from left, S. ovina, S. intermedia (with gelatinous sheath characteristic of the genus), S. lageniformis, S. vexans, S. bipartis and S. minima.

13(12)
Spores 65-95 × 15-18µm. Sporormiella megalospora
- Spores longer than 90µm. 14
14(13) Spores 90-118 × 15-20µm. Asci tapering gradually from the broadest part near the apex to a 'stipe'.
Sporormiella ovina (figs 18, 21)
- Spores 91-114 × (14)18-21µm. Asci cylindrical, abruptly contracted below to a short 'stipe'.
Sporormiella borealis
15(12) Spores mostly less than 35µm long. 16
- Spores mostly between 35-60µm long. 19
16(15) Spores less than 25µm long. 17
- Spores 25-35(38)µm long. 18
17(16) Spores (15)17-24(26) × 5-7µm, end cells broadly conical. Ascospores uniseriate. Asci 120-135µm long. Pseudothecia 250-300µm diam.
Sporormiella pulchella
- Spores 16-22 × 4.5-5.5µm, end cells subovate. Ascospores biseriate. Asci 95-125µm long. Pseudothecia 300-350µm diam.
Sporormiella nigropurpurea
18(16) Spores 30-38.5 × 5.5-6.5µm. Asci clavate, tapering gradually below to a 'stipe'.
Sporormiella leporina
- Spores 27-36(38) × 4-6(8)µm, tending to break in two at the middle septum. Asci cylindrical, abruptly contracted below.
Sporormiella minima (fig. 21)
19(15) Spores with end cells rounded. Asci cylindrical, abruptly contracted below. 20
- Spores with end cells tapered and slightly conical. Asci clavate, tapering gradually to a long stalk. 21
20(19) Spores 45-65 × 8-11.5µm.
Sporormiella intermedia (figs 19-21)
-
Spores 38-46 × 6.5-8µm. Sporormiella australis
21(19) Spores 45-60 × 11.5-14µm, germ slits parallel with long axis.
Sporormiella grandispora
- Spores 35-45(48) × 7-9(10)µm.
Sporormiella lageniformis (fig. 21)
22(11)
Spores 5-celled, 70-80 × 17-19µm. Sporormiella pentamera
- Spores more than 5-celled. 23
23(22) Spores 7- or 8-celled. 24
-
Spores 13-celled, 46-60 × 9-10µm. Sporormiella antarctica
24(23) Spores 7-celled. 25
- Spores 8-celled. 26
25(24) Spores 40-55 × 7-9µm, readily disarticulating, the end cells longer than wide, the rest shorter than wide.
Sporormiella vexans (fig. 21)
- Spores 70-80 × 16-18µm, end cells rounded.
Sporormiella heptamera
26(24) Spores mostly longer than 45µm. 27
- Spores less than 50µm long, not disarticulating at the central septum. 28
27(26) Spores 45-60 × 5-7.5µm, disarticulating at the central septum, all cells the same width.
Sporormiella bipartis (fig. 21)
- Spores 50-59 × 10-12µm, not disarticulating, 3rd cell down wider than the others.
Sporormiella corynespora
28(26) Spores (33)37-40(49) × 7-9µm, cylindrical. Asci abruptly contracted below.
Sporormiella pascua
- Spores 40-48 × 7-8µm, fusiform cylindrical. Asci gradually tapered below.
Sporormiella octomera
29(6) Spores obviously 2-celled at maturity. 30
- Spores 1-celled, or appearing 1-celled at maturity. (Those of Podospora, Schizothecium etc. are 2-celled in early stages of their development, but only one cell matures to become pigmented; the other remains hyaline, often collapses, and may be difficult to see). 47
30(29) Spores 23-28 × 13-17µm, upper cell dark, 15-19µm, with close, blunt spines giving the impression of a pitted spore surface, with apical germ pore, the lower cell hyaline, 6-8.5µm, smoky-brown. Asci unitunicate, 4-spored. Perithecia 400µm diam.
Apiosordaria verruculosa (fig. 24)
- Both cells of spore similar in shape, size and colour. 31
31(30) Asci unitunicate. Spores with a 'gelatinous' appendage at each end. Perithecial neck with setae. 32
- Asci bitunicate. Spores without gelatinous appendages, although a sheath may be present. 33
32(31) Spores 38-48 × 11-14µm, appendages longitudinally fibrillate.
Zygospermella striata
- Spores 46-68 × 11-17µm, appendages hollow, not fibrillate.
Zygospermella insignis (fig. 25)
33(31) Spores with each end truncated by a germ pore. Pseudothecia with dark bristles at neck.
(Trichodelitschia) 34
- Spores with rounded ends and germ slits along the sides. Pseudothecial neck smooth or hairy, but without setae.
(Delitschia, fig. 26) 36
34(33)
Spores 28-34 × 9-12µm. Trichodelitschia aedelphica
- Spores smaller. 35
35(34) Spores 20-27.5 × 8-11µm.
Trichodelitschia bisporula (figs 22, 23)
-
Spores 18-21 × 6-7µm. Trichodelitschia munkii
36(33) Asci ca 256-spored. Spores 14-15 × 6-8µm.
Delitschia myriaspora
- Asci 8-spored. 37
37(36) Spores less than 20µm long. 38
- Spores more than 20µm long. 41
38(37)
Spores 8-11 × 3-5µm. Delitschia perpusilla
- Spores 10-20µm long. 39
39(38)
Spores 10-14 × 5-6µm. Delitschia marchalii
- Spores longer. 40
40(39) Spores 14-18 × 6-10µm, uniseriate. Asci 70-90 × 7-16µm.
Delitschia niesslii
- Spores (16)18-20(22.5) × 6-7.5µm, biseriate. Asci 80-145 × 20-25µm.
Delitschia consociata (fig. 26)
41(37) Spores mostly wider than 20µm. 42
- Spores mostly less than 20µm wide. 43
42(41)
Spores 50-64 × 19-23µm. Delitschia furfuracea
- Spores 50-70 × 25-33µm.
Delitschia winteri (fig. 26)
43(41) Spores 20-25 × 4.5-6µm, the cells slightly tapered and almost completely separated. Pseudothecia hairless, globose, ca 200µm diam.
Delitschia leptospora (fig. 26)
- Spores longer and wider. 44
44(43) Spores transversely septate. 45
- Spores obliquely septate, deeply constricted at the septum, 35-50 × 15-18µm.
Delitschia didyma
45(44) Pseudothecia hairy. Spores 37-50 × 17-20µm, not deeply constricted at the septum.
Delitschia chaetomioides
- Pseudothecia smooth. 46
46(45) Spores biseriate, 45-55 × 13-16µm, one cell usually larger than the other, deeply constricted at the septum and readily separating.
Delitschia canina
- Spores uniseriate, 40-55 × 16-21µm, both cells equal.
Delitschia patagonica
Figures 22-26

Fig. 22. Trichodelitschia bisporula, pseudothecium.
Fig. 23. T. bisporula, expanded ascus broken through the outer wall, with spores.
Fig. 24. Apiosordaria verruculosa, ascospores.
Fig. 25. Zygospermella insignis, ascus and ascospore.
Fig. 26. Ascospores of, from left, Delitschia winteri, D. consociata and D. leptospora.

47(29) Spores with colourless 'gelatinous' secondary appendages (caudae, fig. 28) at one or both ends (not always easy to see; mounting in Indian ink is useful, and essential for some). A hyaline (empty) cell, the primary appendage (fig. 28), may also be present. 48
- Spores without caudae, although a colourless gelatinous sheath may be present. Primary appendages present or absent. 88
48(47) Perithecia often hairy or tomentose when young. Immature spores long, wavy cylindrical, with a row of globules, and more likely to be seen than mature spores (fig. 29). Secondary appendages thin, simple, up to 60 × 3µm. Mature spores with a dark cell 14-25 × 7-13µm and pedicel (primary appendage) 25-50 × 3-6µm.
(Cercophora) 49
- Perithecia often with scales or setae at the neck or tomentose. Caudae, simple or compound. Immature spores clavate or ellipsoid, not long, wavy cylindrical. Mature spores readily observed. 51
49(48) Immature spores 45-70 × 4-6µm. 50
- Immature spores smaller, 38-52 × 3-3.5µm. Mature spores with upper (dark) cell 14-18 × 7-9µm; hyaline pedicel 27-36 × 3-3.5µm.
Cercophora silvatica
50(49) Perithecia with white or grey tomentum. Young spores 45-65 × 4.5-6µm. Mature spores with upper cell 17-25 × 8.5-13µm and pedicel 30-50µm long.
Cercophora coprophila (fig. 29)
- Perithecia with flexuose brown hairs and, at the neck, tufts of agglutinated, swollen, obtuse hairs. Young Spores 52-68 × 4-5µm. Mature spores with upper cell 15-25 × 9-11µm and pedicel 35-45µm long.
Cercophora mirabilis
51(48) Primary appendage absent.
(Arnium, fig. 28) 52
- Primary appendage present. 60
52(51) Asci (64-)128-spored. Spores 18-26 × (10)12-15µm. Perithecial neck sometimes with rigid, brown, septate hairs up to 330µm.
Arnium leporinum
- Asci 4- or 8-spored. 53
53(52) Asci 4-spored. 54
- Asci 8-spored. 55
54(53) Spores ellipsoid, sometimes inequilaterally flattened, 44-54 × 22-30µm, with 1 apical germ pore, caudae not swelling in water. Perithecium usually with lateral tufts of agglutinated hairs up to 550µm long.
Arnium arizonense
- Spores evenly ellipsoid-fusiform, 31-55 × 18-25µm, with germ pore at each end, caudae covering germ pores, 35-60 × 7-11µm, but rupturing and swelling to up to 130 × 50µm, and becoming diffuse and irregular. Perithecial neck covered with rigid hairs up to 190 × 2.5µm.
Arnium hirtum
55(53) Perithecial neck distinctly setose with rigid hairs. 56
- Perithecial neck without setae. 57
56(55) Spores evenly ellipsoid-fusiform, 31-55 × 18-25µm, with germ pore at each end, caudae covering germ pores, 35-60 × 7-11µm, but rupturing and swelling up to 130 × 50µm, and becoming diffuse and irregular. Perithecial neck covered with rigid hairs up to 190 × 2.5µm.
Arnium hirtum
- Spores slightly inequilateral, 35-43 × 17-23µm, caudae 50-75 × 5-8µm, not covering germ pores. Perithecial neck with brown hairs up to 250µm long.
Arnium cervinum
57(55) Perithecia covered with a dense tomentum of septate flexuous hairs. Spores mostly longer than 45µm. Only occasionally fimicolous. 58
- Perithecia without a tomentum. Spores up to 45µm. 59
58(57) Spores (40)45-54 × 25-35µm, uniseriate. Tomentum pale or grayish.
Arnium olerum
- Spores 47-70 x 20-30µm, biseriate above. Tomentum olivaceous brown.
Arnium tomentosum
59(57) Spores somewhat inequilateral, rounded below, pointed above, 31-40 × 18-24µm, caudae 50-120 × 6-10µm, with 1 apical germ pore not covered by cauda.
Arnium caballinum
- Spores equilateral, 36-44 × 20-23µm, caudae 50-80 × 6-8µm, covering germ pores.
Arnium mendax
60(51) Perithecia with scales at the neck, composed of inflated and agglutinated cells (fig. 27, S. conicum).
(Schizothecium) 61
- Perithecia setose or hairy at the neck, but not with inflated cells, or neck black but almost hairless.
(Podospora) 70
61(60) Asci 4-spored. 62
- Asci 8-spored. 63
62(61) Spores 11-14.5 × 6.5-9µm.
Schizothecium nanum (fig. 28)
-
Spores 19-24 × 12-14.5µm. Schizothecium tetrasporum
63(61) Spores more than 30µm long. 64
- Spores less than 30µm long. 65
64(63) Perithecia crowned with a fascicle of long agglutinated hairs at the neck, up to 335µm long. Spores 31-40 × 15-25µm, biseriate.
Schizothecium aloides
- Perithecia with shorter, less remarkable tufts. Spores 30-45 × 19-24µm, ± uniseriate.
Schizothecium glutinans
65(63) Perithecial neck with rigid setae, as well as agglutinated hairs (which may be greatly reduced). Asci 140-210 × 19-25µm, broadest at the markedly rounded apex. Spores 18-23 × 11-14µm.
Schizothecium pilosum
- Perithecial neck without rigid setae. Asci broadest in the middle. 66
66(65) Spores mostly over 23µm long. 67
- Spores up to 23µm long. 69
67(66) Spores 22-25(27) × 11-13µm. Scales at neck distinct.
Schizothecium hispidulum
- Spores wider, 12-19µm 68
68(67) Perithecia 0.5-1mm high, scales at neck usually well developed. Spores (23)26-30 × 12-17µm.
Schizothecium conicum (fig. 27)
- Perithecia 1-2mm diam., subpyriform, neck velvety with indistinct scales. Spores 24-28 × 15-19µm.
Schizothecium squamulosum
69(66) Spores 17-23 × 8.5-13.5µm, primary appendage slender cylindrical, 6-8 × 2µm. Perithecia 0.25-0.7mm high, sometimes with poorly developed scales.
Schizothecium vesticola (fig. 28)
- Spores 11-14 × 6-8µm, primary appendage short, 2µm long, almost triangular. Perithecia 0.3-0.45mm high, with short agglutinated hairs.
Schizothecium cervinum
70(60)
Asci 4-spored. Spores 35-40 × 18-19µm. Podospora pauciseta
- Asci with more than 4 spores. 71