Geastrum senoretiae

Geastrum senoretiae J.C. Zamora in Zamora et al., Mycologia 106: 1205. 2014. [pdf]

MycoBank MB800471 

AUTHORS: Zamora, J.C. & Sánchez, L.
Taxonomic classification

phy Basidiomycota

sbp Agaricomycotina

cls Agaricomycetes

sbc Phallomycetidae

ord Geastrales

fam Geastraceae

gen Geastrum

sp Geastrum senoretiae


Basidiocarps subglobose just prior expansion, hypogeal. Exoperidium splitted in 4–8 unequal rays, 8–29 mm diam. apparently, 13–31 (–35) mm diam. when forced in horizontal position, mostly arched but sometimes planar, not saccate when mature, not hygrometric although some basidiomata may show the tips of the rays curved to the endoperidial body. Mycelial layer thin, whitish to pale cream, strongly intermixed with debris from the substrate, attached to the fibrous layer (rarely peeling off in some areas). Rhizomorphs sometimes present, up to 9 mm long, whitish, and intermixed with debris. Fibrous layer mostly papyraceous when denuded, sometimes moderately coriaceous, whitish to cream colored. Pseudoparenchymatous layer whitish to pale cream in newly expanded, fresh basidiomata, soon cream to ochraceous cream, later ochraceous brown to brownish, darker when dried, frequently cracked, attached to the fibrous layer, up to 1.5 mm thick when fresh, <0.2 mm thick in dry state, not very persistent. Endoperidium subglobose to ovoid, sometimes irregular, 3–10 mm diam., pale ochraceous brown to dark greyish brown; endoperidial surface mostly glabrous or almost so, rarely with very scattered and short protruding hyphae, with small crystals from the mesoperidium in young basidiocarps. Peristome finely plicate, mostly with the same color as the endoperidium or slightly lighter or darker, conical to almost flat, rarely irregular, <0.5–1.5 (–2) mm high, indistinctly to very faintly delimited, with (19–) 23–48 (–65) shallow folds, ≤0.2 mm depth, sometimes reduced to irregular ridges; ostiole often fimbriate. Stalk almost absent or very short, 0–0.8(1) mm high, whitish to cream. Apophysis absent or poorly developed, with the same color or slightly lighter than the rest of the endoperidium. Mature gleba dark greyish brown. Columella weak, subglobose to broadly ellipsoid, about 1.5–3 mm high.

No basidiocarps in a proper basidial state seen, but sporadic sclerified basidia have been observed in some mature basidiomata of the holotype, being ellipsoid to clavate, rarely subglobose, mostly stalked, 10–22.5 × 6–10.5 µm (stalk not included), stalk 1.5–6 µm long, complete clamps were not observed at basis, but a basal “clamp scar” is often visible; mostly with cytoplasmic drops; thin- to thick-walled, walls almost hyaline to brownish; with 2–6 apical sterigmata, 1–2 µm long. Basidiospores globose, 4–5.5 µm (n= 200) diam. including ornamentation, brownish to yellowish brown, with 0.3–0.6 (–0.8) µm high brown warts. Capillitial hyphae 3–7.5 µm wide, aseptate, very rarely branched, mostly straight, thick-walled (walls 1.5–3 µm thick), with narrow lumen, mostly visible; tips acute to rounded, about 1–2.5 (–3) µm diam.; surface naked or encrusted with debris. Prismatic crystals up to 10 × 7 µm, and bipyramidal crystals up to 12 µm diam., sometimes present in the mature gleba. Endoperidium composed of 5–11 µm wide, brownish to yellowish brown, aseptate, mostly unbranched, slightly sinuous, strongly intertwined, thick-walled (walls 1.5–4 µm thick) hyphae, lumen visible; surface normally with few protruding hyphae, not well differentiated from the rest, 7–13 µm wide, and some bipyramidal crystals, about 5–15 µm diam. Peristomal hyphae (5–) 6–11 µm wide, aseptate, mostly unbranched, thick-walled (walls 2–3.5 µm thick), lumen visible, slightly sinuous, narrowing  at base and apex, tips mostly rounded, a few acute, (2.5–) 3–5(6.5) µm  diam.; surface more or less naked or with a few encrusted debris. Mesoperidium difficult to discern, present at least in the youngest basidiomata but reduced, consisting of 2–15 µm diam. bipyramidal crystals and a few (2–) 2.5–3 µm wide, hyaline, branched, thin-walled, clamped hyphae. Pseudoparenchymatous layer of thin-walled (walls c.1 µm thick), hyaline to yellowish cells, variable in shape and size, about 35–90(100) µm diam. Fibrous layer with 3.5–7 (–7.5) µm, hyaline to yellowish, aseptate, straight or slightly sinuous, intertwined, mostly unbranched, thick-walled (walls 1.5–2.5 µm thick) hyphae, lumen visible. Mycelial layer double-layered; inner layer consisting of 2–4 µm wide, strongly glued together, more or less hyaline, branched, thin-walled and clampled hyphae; outer layer with 1.5–3.5 (–4) µm wide, hyaline to somewhat yellowish, aseptate, rarely branched, comparatively more or less thick-walled (walls 0.5–1.5 µm thick) hyphae, lumen very narrow and difficult to perceive. Rhizomorphs mainly made up of 1–3 µm wide, hyaline to slightly yellowish, aseptate, sparsely branched, comparatively thick-walled (walls c.0.5–c.1.5 µm thick) hyphae, without lumen or with an almost indistinct lumen; some thin-walled, clamped hyphae present in the core; rose-like aggregates of bipyramidal crystals observed on the surface.


Ecology and distribution

The species was found in rather anthropized localities of “Iberian sclerophyllous and semi-deciduous forests”, and “Northeastern Spain and Southern France Mediterranean forests” ecoregions (Mediterranean forests, woodlands and shrub biome of the Paleartic ecozone). These areas are located in clayish or sandy, and neutral or slightly acidic soils, which climacic vegetation should be Quercus ilex s.l. (including Q. rotundifolia) woodlands, but alternatively they may include Cistus spp. and Erica arborea shrubs, or implanted Pinus trees, with patches of naked soil in the most degraded parts. ESP: B (unpublished), Cc, CR, Co, J, Or.


References of the species in our territory
  • Zamora JC, Calonge FD, Martín MP. 2014. Combining morphological and phylogenetic analyses to unravel systematics in Geastrum sect. Schmidelia. Mycologia 106(6): 1199–1211. (Protologue) [ESP: Cc, CR, Co, J, Or] [pdf]


Specimens in scientific collections

* sequenced material

Reference specimen marked in bold

  • B: Herb. L. Sánchez LSS20151121-1; LSS20151128-4; LSS20161117-3.
  • Cc: Herb. Zamora 145*.
  • CR: MA-Fungi 39564*.
  • Co: MA-Fungi 30257.
  • J: MA-Fungi 86915* (holotype), isotypes in AH 44862 and UPS F-700348; herb. Zamora 144; herb. Zamora 451; herb. Zamora 534.
  • Or: MA-Fungi 32382*; MA-Fungi 32120.


Sequences in public databases obtained from material collected in our territory

Left: fruiting bodies. Upper right: detail of the peristome. Lower right: detail of the stalk. MA-Fungi 86915 (holotype).

Fruiting bodies. Herb. Zamora 451.

Fruiting bodies. Herb. Zamora 451.

Fruiting bodies. Herb. LSS20161117-3.

Fruiting bodies. Herb. LSS20151128-4.

Basidiospores under the light microscope. Herb. LSS20151121-1.

Micromorphological characters. Left: endoperidial surface with calcium oxalate dihydrate crystals and some collapsed generative hyphae. Right: basidiospore. MA-Fungi 86915 (holotype).