19(18) Spores with a collar at the base of the apiculus. 20 - Spores without a collar at the base of the apiculus, 16-21 × 8-12µm. Thecotheus apiculatus
20(19) Apothecia white. Spores 20-22 × 10-12µm, apiculus 4-6µm diam. Thecotheus perplexans - Apothecia yellowish. Spores 12-15 × 7.5-9µm, apiculus 2.5-3.5µm diam. Thecotheus africanus
21(16) Spores smooth, without guttules. 22 - Spores verruculose or spinulose, 15-18 × 8-9µm, with 1 guttule. Paraphyses with clavate apices, with brown contents. Apothecia asymmetrical, extended on one side. Peziza pleurota
22(21) Spores 19-24 × 10.5-14µm. Apothecia yellowish brown, up to 10cm diam. Peziza vesiculosa - Spores up to 10µm wide. 23
23(22) Apothecia ca 1cm diam., umber with a paler margin. Spores 15-22 × 9-10µm. Peziza bovina - Apothecia up to 2cm diam., pale brown. Spores 13-16 × 7-9µm. Peziza fimeti
24(14) Apothecia robust, up to 4mm diam., orange or with brownish or purple tints. 25 - Apothecia smaller, rarely more than 1mm, pale, yellowish green, orange, grey or chestnut. 32
25(24) Apothecia orange or red. 26 - Apothecia discrete, brownish or purple. (Fimaria) 27
26(25) Apothecia crowded, 1-3mm diam., orange, with a granular surface. Asci up to 190 × 15µm. Spores 15-18.5 × 7-9.5µm. Paraphyses strongly clavate to apex up to 14µm diam, filled with orange granules. Coprobia granulata - Apothecia discrete, 1-2mm diam., orange or red. Asci 240 × 10-12µm. Spores 12-15 × 7-8µm. Paraphyses yellow, only slightly swollen from 2µm to 3-4µm at apex. Ascophanus bresadolae
27(25) Spores 8-9.5 × 4-4.5µm. Fimaria equina - Spores larger. 28
28(27) Spores 20-38 × 10-13µm. Fimaria hepatica - Spores shorter. 29
29(28) Spores 10-13 × 7-9µm. Fimaria porcina - Spores 13-17 × 7-11µm. 30
30(29) Disc punctate with asci. Paraphysis tips swollen up to 3-5µm. Spores 14.5-16 × 9.5-11µm. Fimaria leporum - Disc not punctate with asci. Paraphysis tips not or only slightly swollen. 31
31(30) Apothecia pale yellowish. Spores 13-15.5 × 7.5-8.5µm. Fimaria theioleuca - Apothecia chestnut/purplish brown. Spores 14-17 × 7-8.5µm. Fimaria cervaria
32(24) Spores less than 10µm long. 33 - Spores mostly longer than 10µm. 36
33(32) Paraphyses markedly capitate to 5-6µm, with yellowish green contents. Apothecia dull at first, yellowish at maturity. Spores 7-10 × 2-4.5µm. Thelebolus microsporus (fig. 5) - Paraphyses only slightly inflated above, without coloured contents. Apothecia whitish or grey. 34
34(33) Spores 5-7 × 3-4µm. Asci 38-42 × 6-7µm. Apothecia smoky grey, 0.3-0.4mm diam. Ascophanus cinerellus - Spores larger. Apothecia pale, white or yellowish. 35
35(34) Apothecia up to 1.2mm diam. Asci short stalked, 40-55 × 8-12µm. Spores 7.5-9 × 4.5-5.5µm. Coprotus glaucellus - Apothecia 0.2-0.5mm diam. Asci attenuate below, 65-85 × 10-15µm. Spores 8-10 × 5-6.5µm. Coprotus lacteus
36(32) Apothecia chestnut brown up to 1mm diam. Asci 160 × 13µm. Spores 13-16 x 8-11µm. Paraphyses forked, with swollen tips. Ascophanus misturae - Apothecia lighter coloured. Asci less than 150µm long. 37
37(36) Spores 14-18 × 9-11µm. Apothecia pale yellow/orange, up to 1.5mm diam. Asci cylindrical, 110-150 × 12-15µm. Paraphyses yellowish, slightly inflated to 4-5µm at apices. Coprotus ochraceus - Spores less than 15µm long. Apothecia up to 0.6mm diam. Asci less than 100µm long. 38
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
Keys to Fungi on Dung · The Wunder Library — complete classics, free to read, with narration.