Appendices: Keys to Taxa Glomeromycota Species 1.1 Appendix A: Key to Taxa Gigaspora Species Proposed by Gerdemann and Trappe in 1974 1a Azygospores hyaline to yellow or yellowish green, smooth 2 1b Azygospores light to dark brown 4 2a Spores hyaline when fresh, with brown suspensor-like cells and G. gilmorei brown knobby, clustered soil-borne vesicles 2b Spores hyaline to yellow or greenish-yellow with concolorous 3 suspensor-like cells smooth to echinulate soil-borne vesicles 3a Globose spores less than 300 μm diam; vesicles smooth to knobby, G. formed singly calospora 3b Globose spores generally larger than 300 μm; vesicles echinulate G. gigantea formed in clusters 4a Globose spores larger than 300 μm, ornamented with scattered, G. irregularly shaped, hyaline warts and ridges 2 μm tall; vesicles coralloidea coralloid 4b Globose spores less than 300 μm, ornamented with minute spines; G. vesicles smooth (extra-limital species). heterograma © Springer International Publishing Switzerland 2015 129 T. Souza, Handbook of Arbuscular Mycorrhizal Fungi, DOI 10.1007/978-3-319-24850-9 130 Appendices: Keys to Taxa Glomeromycota Species 1.2 Appendix B: Key to Taxa Family Endogonaceae Proposed by Tandy in 1975 Chlamydospores are subtended by one hypha, and the spore and sporophore contents are directly connected or divided by a distinct septum. Zygospores are subtended by two hyphae and the endospore in continuous 1a Sporocarp containing zygospores 2 ( Endogone spp.) 1b Sporocarp containing chlamydospores 6 ( Glomus spp.) 2a Zygospores aggregated in distinct groups 3 2b Zygospores not aggregated, scattered throughout 5 fructifi cation 3a Zygospore wall in one thick (9–22 μm) layer Endogone crassa 3b Zygospore wall in two distinct layers, 25 μm together 4 4a Gametangia usually widely separated, discrete Endogone aggregata 4b Gametangia fused Endogone tuberculosa 5a Zygospore surrounded by a whorled sheath in surface Endogone view resembling a fi ngerprint fl ammicorona 5b Zygospore surrounded by a ramifying sheath, reticulate Endogone reticulata in surface view 6a Chlamydospore with septum at its base Glomus pulvinatus 6b Chlamydospore without septum at its base 7 7a Chlamydospore mostly more than 130 μm in diameter Glomus macrocarpus var. macrocarpus 7b Chlamydospores less than 130 μm in diameter 8 8a Chlamydospore wall in one thick (3–4 μm) layer, Glomus tubiformis sporophore usually occlused 8b Chlamydospore wall in two layers, to 8 μm together, Glomus tener sporophore open 1.3 Appendix C: Key to Taxa Family Endogonaceae Proposed by Nicolson and Schenck in 1979 Key to Florida Endogonaceae 1a Forming chlamydospores free in the soil, in sporocarps or within 2 roots 1b Forming azygospores on terminally swollen hyphae 3 2a Chlamydospores only in sporocarps containing a single tightly Sclerocystis packed layer of spores around a central plexus of hyphae 2b Chlamydospores usually free in soil or within roots; if in a Glomus sporocarp, not as in 2 above (continued) (continued) 3a Azygospores terminally attached to a swollen hyphal tip Gigaspora (suspensor-like cell) that frequently bears a smaller hypha projecting towards the spore; Spores usually free in soil with a bulbous (suspensor-like cell) attachment 3b Azygospores laterally attached to a swollen hypha tapering to a Acaulospora large terminal vesicle which collapses with age; spores usually free in the soil with no hyphal attachment Glomus 1a Chlamydospore walls on mature spores predominantly hyaline, 2 white or yellow occasionally becoming dark yellow to brown with age 1b Chlamydospore walls on mature spores predominantly brown to 5 black, occasionally yellow brown when young 2a Chlamydospore walls hyaline (becoming yellow with age), walls Glomus clarus 7–31 μm thick, frequently formed within the roots 2b Chlamydospore walls yellow to yellow brown, not formed within 3 the roots 3a Hyphal attachment to spore frequently funnel shaped, spores Glomus 100–300 μm in diam, spores formed ectocarpically or within mosseae sporocarps of 1–10 spores 3b Hyphal attachment not funnel shaped, spores usually less than 4 100 μm 4a Spores greater than 50 μm in diam, usually formed in sporocarps Glomus fulvus above the soil surface 4b Spores 50 μm in diam or less, hypogeous Glomus microcarpus 4c No spores usually formed, when present 10–12 μm in diam; Glomus tennis hyphae on roots thin (0.5–3.0 μm wide), with irregular swellings 5a Spores formed ectocarpically or in old roots, spore diam not 6 exceeding 150 μm 5b Spores not formed in old roots, spore diam frequently exceeding 7 150 μm 6a Young spores with an ephemeral outer wall up to 5 μm thick and a Glomus laminate inner wall 2–8 μm thick etunicatus 6b Spore without an ephemeral outer wall; spore wall yellow brown, Glomus 3–17 μm in diam; spores frequently tightly packed in sporocarps fasciculatus 7a Chlamydospores dark brown to black; not formed in sporocarps G. macrocarpus v. geosporus 7b Chlamydospores yellow brown; spores formed ectocarpically or in G. sporocarps macrocarpus v. macrocarpus Sclerocystis 1a Sporocarps enclosed in a peridium 2 1b Sporocarps not in a peridium; resembling a miniature blackberry Sclerocystis rubiformis 2a Sporocarp peridium composed of thick walled, sinuous hyphae Sclerocystis tightly enclosing the spores sinuosa 2b Sporocarp peridium without sinuous hyphae Sclerocystis coremioides (continued) 132 Appendices: Keys to Taxa Glomeromycota Species (continued) Acaulospora 1a Azygospores over 100 μm in diam 2 1b Azygospores less than 100 μm in diam Acaulospora trappei 2a Azygospores with two readily separable walls; outer spore wall Acaulospora with cerebriforme folds up to 12 μm tall gerdemannii 2b Azygospores without readily separable walls, walls smooth Acaulospora laevis Gigaspora 1a Azygospores light brown to dark brown or black 2 1b Azygospores hyaline, white, yellow or greenish yellow 5 2a Azygospores wall black, pitted with pores; spores over 250 μm Gigaspora diam; accessory vesicles in clusters nigra 2b Azygospores light to dark brown 3 3a Azygospores 250 μm or larger 4 3b Azygospores usually less than 250 μm; outer wall with minute Gigaspora spines; accessory vesicles in clusters heterograma 4a Accessory vesicles in clusters; outer wall continuous with Gigaspora irregular shaped projections 1–7 × 3–12 μm gregaria 4b Accessory vesicles borne singly, coralloid; wall surface with Gigaspora openly spaced hyaline ridges 2 μm tall by 0.5 6 μm broad (not coralloidea known to occur in Florida) 5a Azygospores with an outer wall readily separating under pressure 6 from the inner wall; azygospores hyaline 5b Azygospores without separable walls 7 6a Azygospores under 250 μm in diam; suspensor cell hyaline; Gigaspora accessory vesicles brown, knobby, borne singly or in clusters pellucida 6b Azygospores over 250 μm in diam; suspensor cell light brown; Gigaspora accessory vesicles pale brown, knobby, borne in clusters (not gilmorei known to occur in Florida) 7a Azygospore walls consisting of one layer, usually less than 5 μm Gigaspora thick; spores hyaline, white or shades of yellow; accessory calospora vesicles knobby, borne singly (not known to occur in Florida) 7b Azygospore walls consisting or more than one layer; accessory 8 vesicles borne in clusters 8a Azygospores predominantly some shade of yellow 9 8b Azygospores predominantly some shade of white 10 9a Azygospores yellow to greenish yellow; accessory vesicles spiny, Gigaspora borne in clusters; suspensor-like cell 41–51 μm in diam gigantea 9b Azygospores pale yellow to dull yellow, never turning greenish Gigaspora yellow; accessory vesicles in clusters, spiny to knobby; suspensor- aurigloba like cell 40–70 μm diam 10a Azygospores white to cream with a pink tint in the area of the Gigaspora suspensor-like cell; spores usually less than 300 μm in diam rosea 10b Azygospores white to cream; usually greater than 300 μm in diam Gigaspora margarita Appendices: Keys to Taxa Glomeromycota Species 133 1.4 Appendix D: Key to Taxa Family Endogonaceae Proposed by Hall and Fish in 1979 1a Sporocarps present, may be fused into mats; if few spores 2 in sporocarp (1–4) then peridium well-developed 1b Sporocarps absent but spores may be aggregated into loose 57 clusters 2a Spore sessile or spore attachments not seen (attachments 3 may be obscured by peridial hyphae) 2b Spore not as above 11 3a Spore wall single, or, if double, outer wall thin and diffi cult 4 to discern; if single may be laminate 3b Spore wall double or multiple 7 4a Sporocarp often exuding a sticky latex when cut; spores Glomus melanosporus containing a white latex; spore wall grading in colour from Gerdemann and Trappe dark at outer surface to subhyaline near inner surface 4b Sporocarp not exudes sticky latex when cut; spores not 5 containing White latex; spore wall uniform in colour 5a Spores in sporocarps arranged in single layer around a Sclerocystis sinuosa central plexus of sterile hyphae; peridium of tightly Gerdemann and Bakshi 5b Spores in sporocarps arranged randomly 6 6a Spores enclosed in tightly appressed hyphal mantles Glomus convolutus (cursory exanimation may suggest that the mantle is an Gerdemann and Trappe ornamentation of the spore wall); diam of sporocarps greater than 1 mm 6b Spores not enclosed in hyphal mantles; diam of sporocarps 21 less than 1 mm 7a Sporocarps often exuding sticky latex when cut; hyphal 46 mantle may be present 7b Sporocarps never exuding sticky latex when cut; Hyphal 8 mantle never present 8a Spores sessile or almost sessile, borne in a cluster on the Glomus fuegianus (Speg.)