Geastrum tenuipes (An earthstar)

The spore sac of Geastrum tenuipes (1) is between 1 and 2 cm in diameter; (2) has a strongly pleated, conical mouth; (3) is held up from the star-like base by a slender stem, which may grow to more than 5 mm in length. The spore sac may be slightly kinked towards its base and the base may be grooved. You may see a fleshy collar around the stem, soon after the fruiting body opens, but that collar shrivels and is easily eroded. For many years the name Geastrum pectinatum was used for earthstars of this appearance and that species was thought to be cosmopolitan, but the authors of a 2015 paper (Zamora et al, Persoonia vol. 34, pp. 130-165) concluded that several species were hiding under that name. The Australian material that they studied (including three collections from suburban Canberra) was found to be distinct from other 'pectinatums', but all the Australian collections were the one species, for which the authors used the epithet tenuipes, thereby resurrecting a species name first published in 1848 for a Geastrum collected in Tasmania, but synonymized with Geastrum pectinatum in the interim.