Fig. 5. Thelebolus microsporus, ascus and paraphysis.
Fig. 6. Ascodesmis microscopica, ascospores.

38([37])Apothecia bright yellow. Asci cylindrical clavate, attenuate below, 65-90 × 10-15µm. Spores 12-14 × 6-8.5µm. Paraphyses branched, apices inflated to 4-5µm, with yellow contents.
Coprotus aurorus
-Apothecia white/pale yellow, with darker margin. Asci broadly clavate, stalked below 40-55 × 15-30µm. Spores 9-15 × 6.5-9.5µm. Paraphyses inflated above to 5-8µm, hyaline.
Coprotus granuliformis
39([5])Spores spherical or broadly ellipsoid, brown, ornamented with warts, anastomosing ridges or a reticulum. Asci clavate. Apothecium without excipulum.
(Ascodesmis, [fig. 6]) [40]
-Spores ellipsoid or spherical, hyaline at first, then purple, becoming brown at maturity; epispore smooth, finely verruculose, warted or cracked. Asci cylindrical. Excipulum present.[45]
40([39])
Spores 18-21.5 × 13.5-17.5µm.Ascodesmis macrospora
-Spores up to 16µm.[41]
41([40])Spores ± spherical, L/B ratio mostly up to 1.2.[42]
-Spores ± broadly ellipsoidal, L/B ratio mostly 1.2 or more.[43]
42([41])Spores ornamented with round warts, 8.5-11 × 8.3-10µm.
Ascodesmis nana
-Spores ornamented with a network of ridges, 10.5-14 × 9-12µm.
Ascodesmis sphaerospora
43([41])Spores with a prominent reticulum of ridges ([fig. 6]), 11-15.5 × 8-13.5µm. Apothecia 150-300µm diam.
Ascodesmis microscopica ([fig. 6])
-Spore ornament not a reticulum.[44]
44([43])Spores with 1 simple or branched ridge and isolated or occasionally connected warts, 11-14.5 × 7-11.5µm. Apothecia up to 500µm diam.
Ascodesmis porcina
-Spores with isolated warts, some joined to form short ridges, but not a reticulum, often capitate, 9.5-12.5 × 7.5-10µm. Apothecia 50-150µm diam.
Ascodesmis nigricans
45([39])
Spores separate in the ascus.(Ascobolus) [46]
-Spores firmly joined together, both in the ascus and after ejection ([fig. 10]).
(Saccabolus) [66]
46([45])Spores spherical.[47]
-Spores ellipsoid.[48]
47([46])Spores 10.5-13.5µm, epispore with numerous but isolated warts.
Ascobolus brassicae (figs [8], [9])
-Spores 11.5-13.5(15)µm, epispore with subparallel occasionally anastomosing lines.
Ascobolus crosslandii
48([46])Spores very large, mostly 50-70 × 25-35µm, almost oblong with rounded ends, typically with few cracks in the epispore.
Ascobolus immersus (figs [7], [9])
-Spores smaller, with epispore smooth, warted or with cracks.[49]
49([48])Epispore strongly and irregularly wrinkled with a vesiculose layer of pigment, 11.6-16 × 6.5-9.3µm. Paraphyses capitate up to 18µm. Apothecia up to 0.6mm diam.
Ascobolus rhytidiosporus
-Epispore not strongly wrinkled/vesiculose.[50]
50([49])Epispore basically smooth or warted, perhaps with a few irregular cracks.[51]
-Epispore with a clear pattern of cracks or lines.[56]

Fig. 7. Apothecia of, from left, Ascobolus furfuraceus, A. immersus and A. albidus.
Fig. 8. A. brassicae, ascus with spores and detail of operculum.
Fig. 9. Ascospores of, clockwise from left, A. immersus, A. stictoideus, A. albidus, A. brassicae and A. crenulatus.

51([50])Spores up to 25µm long.[52]
-Spores longer, 25µm or more.[54]
52([51])Epispore smooth, finely granular or punctate. Gelatinous material unilateral, not surrounding spore.[53]
-Epispore warted, spores 18.5-21(22.5) × (9)10-11.5µm, surrounded by gelatinous sheath.
Ascobolus hawaiiensis
53([52])Spores 18-24 × 10-13µm. Hymenial mucus greenish yellow. Excipulum not brown.
Ascobolus mancus
-Spores 20-25 × 11-13µm. Hymenial mucus sulphur yellow. Excipulum with rich brown intercellular pigment.
Ascobolus boudieri
54([51])Epispore smooth or finely granular, spores 23-29(32) × 12-17µm.
Ascobolus elegans
-Epispore warted.[55]
55([54])Spores with a regular pattern of warts and intact epispore, 26-32 × 15-17.5µm.
Ascobolus stictoideus ([fig. 9])
-Spores with irregular patches of thicker pigment, especially at the poles, 28-35 × 16-18µm.
Ascobolus degluptus
56([50])Spores mostly 18 × 10µm or larger.[57]
-Spores mostly smaller than 20 × 10µm.[61]
57([56])Apothecia small, mostly up to 1mm diam., colourless. Spores 20-35 × 11-14µm, epispore cracks distant, irregular, often anastomosing.
Ascobolus albidus (figs [7], [9])
-Apothecia larger, usually 1mm diam. or more, disc yellowish, greenish, purplish or brownish.[58]
58([57])Apothecia crowded, purplish or purplish brown with intercellular pigment. Spores 18-28 × 10-12µm, with longitudinal anastomosing cracks.
Ascobolus roseopurpurascens
-Apothecia yellowish or greenish.[59]
59([58])Spores 17-22 × 9.5-12µm with a few widely spaced and irregularly oriented cracks.
Ascobolus michaudii
-Spores with closely spaced, ± longitudinal, cracks, with varying degrees of anastomosis.[60]
60([59])Apothecia furfuraceous, sessile. Ascus wall blue in iodine. Spores 19-28 × 10-14µm.
Ascobolus furfuraceus ([fig. 7])
-Apothecia smooth, substipitate. Ascus wall only faintly blue in iodine. Spores 19-22 × 9.5-13µm.
Ascobolus perplexans
61([56])Apothecia large, stipitate, 5-10mm diam. Spores 16-19.5 × 8.5-10µm, with subparallel, longitudinal, only rarely anastomosing lines.
Ascobolus lignatilis
-Apothecia up to 2mm diam.[62]
62([61])Apothecia white.[63]
-Apothecia yellow, green or brownish.[64]
63([62])Spores 13-17 × 7.5-8.5µm, with a coarse reticulum of fine cracks when mature. Only recorded on grouse, capercaillie etc. (Tetraonidae) dung.
Ascobolus carletonii
-Spores 16-20 × 8-10µm, with a pattern of longitudinal anastomosing cracks. Only recorded on deer dung.
Ascobolus sacchariferus
64([62])Spores 14.5-16 × 8-9µm, epispore lines not densely crowded.
Ascobolus cervinus
-Spores smaller, epispore with densely crowded, rarely anastomosing cracks.[65]
65([64])Apothecia greenish yellow, furfuraceous, with crenulate margin. Spores 9.5-15 × 6-8µm.
Ascobolus crenulatus ([fig. 9])
-Apothecia brownish yellow to brown, smooth, with undifferentiated margin. Spores 12.5-14.5 × 7-8.5µm.
Ascobolus minutus
66([45])Asci 4-spored. Spore clusters 42-58 × 14-20µm. Spores 16.5-23 × 9.5-12µm, smooth to finely punctate, but with a thick cap or girdle of reticulated or warted pigment.
Saccobolus quadrisporus
-Asci 8-spored.[67]
67([66])Spore clusters ± globular, 17-26(39) × 15-20µm.[68]
-Spore clusters elongated, 2-3 times as long as wide.[69]
68([67])Spore clusters compact, subglobose, with only the exposed surface of spores pigmented, ornamented with small and coarse warts.
Saccobolus dilutellus
-Spores loosely united in cluster, ornamented with small isolated warts covering most of their surface.
Saccobolus globuliferellus
69([67])Apothecia yellow. Spores in 4 rows of 2 longitudinally arranged spores ([fig. 10]).[70]
-Apothecia hyaline or violaceous (some mature darker). Spores in 2 rows of 3 and 1 row of 2 ([fig. 10]).[73]
70([69])Spore clusters 40µm or longer.[71]
-Spore clusters up to 40µm long.[72]
71([70])Spore clusters 50-71 × 16-25µm. Spores 22-29 × 8.5-14.5µm, smooth or rarely finely punctate, with distant irregular cracks.
Saccobolus glaber ([fig. 10])
-Spore clusters 43-51 × 14-17µm. Spores 16-22 × 7.5-9µm, with fine isolated warts.
Saccobolus citrinus
72([70])Spores 14-17.5(19.5) × 7.5-8.5(10)µm, easily separated at maturity. Spore clusters becoming shorter and more rounded with maturity. Apothecia up to 300µm diam., inconspicuous due to their solitary nature and the predominantly brownish colour due to the mature spores.
Saccobolus truncatus ([fig. 10])
-
Spores 11.5-13.5 × 5.5-6.5µm.Saccobolus minimus
73([69])Apothecia white, covered with tapering squamules composed of septate hyphae. Spore clusters 38-43 × 15-17µm. Spores 16-17.5 × 7-8.5µm, smooth or finely punctate.
Saccobolus caesariatus
-Apothecia not white, without tapering scales.[74]
74([73])Spore clusters mostly over 40µm long.[75]
-Spore clusters mostly under 40µm long.[76]
75([74])Spore clusters 38-62 × 14-19µm. Spores 13-21.5 × 6.5-9.5µm, smooth, finely warted or with reticulate cracks. Apothecia 0.2-2mm diam.
Saccobolus versicolor ([fig. 10])
-Spore clusters 42-60 × 18-24µm. Spores very coarsely warted, 17.5-23 × 8.5-10µm (inc. warts).
Saccobolus beckii