E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
{See also Otidea Table.} Features include a lopsided cup-shaped fruitbody with a shorter side that is split lengthwise, an interior spore surface colored tan to grayish brown or yellowish brown, a similarly colored exterior that is often slightly scurfy, brittle yellowish flesh, a short stem-like base (usually present), growth on the ground in woods often along roadsides, and microscopic characters. |Kanouse describes a variety microspora with paler and more yellow color and smaller spores (9-10 x 5.5-6.5 microns) from Washington and California: it was later raised to species status as Otidea microspora (but see SIMILAR section). |She lists var. typica from WA and CA also. |Olariaga(1) consider Otidea alutacea sensu lato to comprise a species complex. We are using the term Otidea alutacea group to represent this Otidea alutacea complex. Their molecular study resolved several clades. "It appears that the spore sizes within each clade have a fairly narrow range, but overlap exists between the clades. Patterns of continental speciation are suggested as well; two clades have North American specimens (clades 2, 4), and the rest contain samples from Europe and Asia" (Otidea alutacea sensu stricto and clades 1, 3a, and 3b). The two North American clades, with non-overlapping spore lengths, correspond to the two species distinguished by Peterson, E.T.(1) as O. alutacea (clade 2) and O. umbrina (clade 4). "Clades 2 and 4 have spores that overlap with European clades, and it is so far problematic to distinguish them using only morphology and disregarding the geographical origin." |E.T. Peterson(1) distinguished the two on the basis of the color of the hymenium in dried specimens: for the long-spored taxon "tawny olive", "sayal brown", or "raw umber", and for the short-spored taxon "pale horn color", "drab-gray", lighter than "chamois" or "tawny olive". Peterson further distinguished the two by saying that in the long-spored taxon the exterior lost color slowly on drying whereas in the short-spored taxon the exterior lost color quickly on drying. Peterson also says (italicizing the Latin names), "O. alutacea tends to be lighter in color and more brittle than O. umbrina and has slightly larger spores", but does not specify whether this refers to fresh or dried specimens. |The Otidea alutacea complex needs more research before names can be assigned to different species. |Olariaga(1) give a detailed description of Otidea alutacea sensu stricto in Europe. The descriptions of Breitenbach(1), Dennis(1), and Hansen, L.(1) would also be describing European members of the group.

Collections in the different clades were examined by Olariaga(1) from WA (4 collections), OR (1 collection) (clade 2), OR (10 collections) (clade 4), Denmark, France, Italy, Norway, Spain, and Sweden (O. alutacea s.str.), Denmark and Sweden (clade 1), Norway and Sweden (clade 3a), and Denmark and Sweden (clade 3b). According to Larsen(1), Otidea alutacea is found in WA, ID, AB, and CA. There are collections from BC at the University of British Columbia by Paul Kroeger and Pam Janszen.

Upper surface:
2-4cm wide, 2-6cm high, "usually cup-shaped but lop-sided (the shorter side split lengthwise or open) and semierect, but often irregularly wavy or contorted with growing in clusters", apex often truncate when growing erect; tan or light brown to grayish brown or brown; smooth, (Arora), 3-6cm tall, slit on the side, often also elongated on one side, but not distinctly ear-shaped; dark loam-colored to dingy gray-brown, (Breitenbach), 2-4cm across, 3-5cm high, cup-shaped or somewhat elongated on one side, split down the other; clay color or grayish brown, (Dennis), 2-4cm broad, 1-3cm high, the vertical split edges often closely inrolled; yellowish brown or pale brownish, (Hansen), 2-4cm wide, 2-6cm high, truncate, "avellaneous" to "wood brown" (fresh), smooth, bald, drying wrinkled, (Kanouse)

Flesh:
brittle (Arora), yellowish (Breitenbach), rather thick; yellowish, (Dennis), fragile (Kanouse)

Underside:
pale to dull brown (or yellowish in one variety), often slightly scurfy, (Arora), dingy ocher (Breitenbach), fawn; finely scurfy, (Dennis), colored as interior; bald, (Hansen), "tawny olive", "pinkish buff" or "cinnamon buff" to "clay color", "wood brown", (dry)

Stem:
"absent or present as a narrowed, whitish, downy base", (Arora), subsessile (Dennis), short (Hansen), subsessile or short stipitate (Kanouse)

Microscopic:
spores 14-16 x 7-9 microns (or smaller in one variety), elliptic, smooth, typically with 2 oil droplets, (Arora), spores 12.5-17.5 x 6-8 microns, elliptic, smooth, colorless, with 2 droplets; asci 250-300 x 8-10 microns; paraphyses slender, 3-4 microns wide, "tips bent over, slightly thickened, septate and forked at the base", (Breitenbach), spores 12-15 x 6-7 microns, with 2 oil drops; asci about 250 x 15 microns; paraphyses slender, curved at tip and sometimes slightly lobed, (Dennis), spores 14-16 x 7-9 microns, (Hansen), spores 14-16 x 7-9 microns, narrowly elliptic, smooth, slightly colored yellowish, with 2 drops, 1-seriate or obliquely arranged in the asci; asci 150-200(250) x 8-10 microns, inamyloid; paraphyses filiform, occasionally branched in lower part one or two times, septate, colorless, apices hooked, (Kanouse), spores for clade 2 are 15-18 x 7-8 microns, for clade 4 are 12-14.5 x 6.5-8.5 microns, for Otidea alutacea sensu stricto are (13.5)14.5-16.5(17.5) x 6.5-7.5(8) microns, for clade 1 are 12-13.5 x 5.5-7 microns, for clade 3a are 13.5-15 x 6.5-8 microns, and for clade 3b are 15.5-17.5 x 7.5-8 microns.