text: parasola auricoma parasola auricoma is a species of agaric fungus in the family psathyrellaceae . first described scientifically in 1886 , the species is found in europe , japan , and north america . the small , umbrella - shaped fruit bodies ( mushrooms ) of the fungus grow in grass or woodchips and are short - lived , usually collapsing with age in a few hours . the caps are up to 6 cm ( 2 . 4 in ) wide , initially elliptical before flattening out , and colored reddish - brown to greyish , depending on their age and hydration . they are pleated with radial grooves extending from the center to the edge of the cap . the slender , whitish stems are up to 12 cm ( 4 . 7 in ) long and a few millimeters thick . microscopically , p. auricoma is characterized by the presence of setae ( thick - walled bristles ) in its cap cuticle . this characteristic , in addition to the relatively large , ellipsoid spores can be used to distinguish it from other morphologically similar parasola species . taxonomy the species was first described in 1886 by french mycologist narcisse théophile patouillard as coprinus . it was transferred to parasola in 2001 when molecular phylogenetics was used to sort the coprinoid genera ( i.e. , coprinus and the segregate genera coprinopsis , coprinellus , and parasola ) into natural monophyletic groups . according to the nomenclatural database mycobank , parasola , described by jakob emanuel lange in 1915 and named in honor of danish mycologist emil christian hansen , is a facultative synonym ( based on a different type ) . although this synonymy is accepted by several authorities , p.d. orton and roy watling disagree , suggesting that c. is a forgotten species that requires reanalysis . in a 2010 study of the type material of several coprinoid taxa , laszlo nagy and colleagues assigned patouillard 's plate 453 ( containing the original description ) as the lectotype for p. auricoma , as they believed it to be " sufficiently diagnostic for a clear - cut definition of this taxon . " they also determined that pseudocoprinus and coprinus ( both species were described in a 1946 publication by alexander h. smith and lexemuel ray hesler ) were conspecific with p. auricoma . the placement of p. auricoma within parasola is somewhat controversial . it has often been classified in the section , a grouping of species characterized by the absence of a veil , and the occasional presence of caulocystidia ( cystidia on the stem ) , pileocystidia ( cystidia on the cap surface ) , or dark setae - like elements . several molecular phylogenetics studies have confirmed its inclusion in the parasola clade , but its relationship to other members of the group have not been fully resolved due to limited sampling . a recent analysis suggests that in the phylogenetic tree of parasola , p. auricoma and p. form a with the crown parasola species . description the fungus produces fruit bodies with caps that are initially egg - shaped with margins curled inward ; as the cap expands , it becomes conical and eventually flat or slightly depressed in the center , ultimately reaching a diameter of 6 cm ( 2 . 4 in ) . the fruit bodies are hygrophanous , and so will change color depending on their state of hydration . when the fruit bodies are young and fresh , the caps are reddish brown and can glisten , especially if wet . as the mushroom matures , the outer edge of the cap turn a greyish color while the center remains reddish brown . radial grooves extend from the center of the cap to the margins . the caps have minute hairs ( setae ) that are visible through a hand lens . the gills are free from attachment to the stem , and have a width of 0 . 2 – 0 . 4 cm ( 0 . 08 – 0 . 16 in ) . they are initially whitish before turning greyish brown , and eventually become blackish with a dark margin as the spores mature . unlike some other coprinoid mushrooms , the gills do not — a process whereby the gills dissolve into an inky black mass as they release their spores . the whitish stem is up to 12 cm ( 4 . 7 in ) long and 0 . 4 cm ( 0 . 16 in ) thick , hollow , and fragile . young fruit bodies can have abundant , thick - walled hairs at the base of the stem , but these typically disappear as the mushroom matures . the flesh is thin , fragile , yellowish to brownish , and lacks any appreciable odor or taste . the spore print is brownish - black . the edibility of p. auricoma is not known with certainty , but the fruit bodies are small and insubstantial . the spores are ellipsoid , have a central germ pore , and measure 10 – 14 by 5 . 75 – 8 μm . the basidia ( spore - bearing cells ) are club - shaped and four - spored . the colorless pleurocystidia ( cystidia on the gill face ) measure 70 – 140 by 20 – 45 μm , and are roughly elliptical to flask - shaped , while the similarly shaped cheilocystidia ( found on the gill edge ) measure 50 – 95 by 15 – 25 μm . clamp connections are present in the hyphae of all tissues of p. auricoma . the cap cuticle comprises a layer of club - shaped , thin - walled cells measuring 25 – 40 by 10 – 30 μm interspersed with long , dark , thick - walled setae . - brown setae are plentiful on the cap surface , and consist of an elongated , hair - like segment up to 315 μm long , attached to the surface by a bulbous base that is 3 – 9 μm wide . similar species several characters serve to help distinguish parasola auricoma from similar coprinoid mushrooms that grow in woodchips , including a lack of deliquescence , and the lack of a veil . microscopically , it is characterized by the long , gold - pigmented , thick - walled setae on the cap , and ellipsoid spores with a germ pore . the distinctly grooved and pleated cap margin indicates that it is allied with the coprinoid species and not with the genus psathyrella . similar parasola species include the common and widespread p. , p. , p. , and p. . only microscopy will definitively separate these from p. auricoma — none of them have setae on the cap . habitat and distribution parasola auricoma is a saprobic species , and so obtains nutrients by breaking down organic matter into simpler molecules . the fruit bodies grow either singly or in groups , often in large numbers , at road sides in deciduous forests , or on grassy areas . the mushrooms are short - lived , usually lasting only for a few hours before collapsing . common in europe and north america ( including hawaii ) , it has also been recorded from japan . in europe , fruit bodies appear most commonly in spring and summer months , while in north america , fruiting is more common in the late summer and autumn , after rains .