Hydnum umbilicatum Peck, Ann. Rep. N.Y. St. Mus. 54: 953 (1902)

Swenie, Rachel A., Baroni, Timothy J. & Matheny, P. Brandon, 2018, Six new species and reports of Hydnum (Cantharellales) from eastern North America, MycoKeys 42, pp. 35-72 : 35

Hydnum umbilicatum Peck, Ann. Rep. N.Y. St. Mus. 54: 953 (1902) Figs 5C, D, 6N, O

Type.

UNITED STATES. New York: Rensselaer County, Sandlake, ground in thin woods, September, ca. 1901, C.H. Peck (holotype: NYS-F-3258). Epitype. UNITED STATES. New York: Cortland County, Lime Hollow Nature Center Tunison Aquatic Lab (42.5578; -76.2486), on humus in wet, boggy area with Tsuga , Betula alleghaniensis , 27 Aug 2014, T.J. Baroni 10651TJB (CORT 012241, epitype here designated).

Description.

Pileus 15-70 mm wide, round, conico-campanulate to irregularly convex, disc shallowly depressed to umbilicate; surface matt, glabrous or felty-fibrillose, orange-cream to orange-brown (5C6-8); margin entire and incurved when young to undulating in age, often paler in color than the rest of the pileus. Spines 1-8 mm long, aculeate, adnexed, fleshy pinkish to light orange (5A2-3). Stipe 20-80 × 4-15 mm, central or eccentric, equal to slightly enlarged downwards, glabrous or densely matted with fluffy fibrillose; white to peachy-pallid buff, staining ochre to medium brownish orange ("Mars Yellow" to "Orange Rufous"). Context white. Odor mild or pleasant. Taste mild, sometimes with nutty aftertaste.

Basidiospores 7.5 –8.4– 9.5 μm × 7 –8– 9 μm, Q=1.00 –1.06– 1.18 (n=97/5), globose to subglobose, smooth, thin-walled, hyaline in KOH. Basidia 43-52 × 7.5-10 μm with (1)2-4 sterigmata. Pileipellis an interwoven cutis, hyphae smooth, cylindrical, thin-walled, mostly 4-8 μm wide. Clamp connections present.

Distribution.

Eastern North America - Michigan, Massachusetts, New York (type), Tennessee, North Carolina, Newfoundland and Labrador (GenBank KX388676), and Quebec (GenBank KX388675).

Ecology.

In coniferous or mixed woods with Tsuga , Pinus , Abies , Quercus , Betula , Fagus . July to November.

Other specimens examined.

UNITED STATES. Massachusetts: Worcester County, Rutland State Park, in arcs scattered singly or gregarious with Quercus , Pinus strobus , 260 m, 1 Nov 2003, P.B. Matheny PBM2511 (TENN 066875). Michigan: Marquette County, Big Bay, Alder Creek, 240 m, 2 Sep 1971, R.H. Petersen TFB36346 (TENN 036346). New York: Tompkins County, Ridgewood Reserve, 305 m, 13 Sep 2007, O. Akinyemi OA14 (CORT 008175). Tompkins County, Eames Bog, 325 m, 22 Sep 2011, B. Demo BD14 (CORT 007319). North Carolina: Transylvania County, Pisgah National Forest, Yellow Gap Road, under Quercus , 850 m, 18 Jul 2000, Jason TFB9766 (TENN 058667). Blue Ridge Parkway near Little Switzerland, coniferous woodlot, 1000 m, 19 Aug 2016, N. Byers RAS103 (TENN 073013). Yancey County, Carolina Hemlocks Recreation Area, picnic area under Tsuga carolinensis , Quercus , possibly Betula or Carpinus , 840 m, 29 Sep 2017, R.A. Swenie RAS234 (TENN 058667). Yancey County, Mount Mitchell State Park, Balsam Mountain trail, under Abies fraseri , 1920 m, 19 Aug 2016, R.A. Swenie RAS099 (TENN 073009). Yancey County, Mount Mitchell State Park, Balsam Mountain trail, under Abies fraseri , 1920 m, 19 Aug 2016, R.A. Swenie RAS101 (TENN 073011). Yancey County, Mount Mitchell State Park, Balsam Mountain trail, under Abies fraseri , 1920 m, 29 Sep 2017, R.A. Swenie RAS238 (TENN 073066). McDowell County, Armstrong Creek trail, under Quercus , Pinus , Liriodendron , 450 m, 30 Sept 2017, R.A. Swenie RAS239 (TENN 073067). Great Smoky Mountains National Park, Big Creek, Baxter Creek Trail, with Tsuga , Pinus , Quercus , 936 m, 25 Aug 2004, E.B. Lickey TFB12039 (TENN 060288). Tennessee: Great Smoky Mountains National Park, Maddron Bald Trail, scattered on soil and hardwood leaf litter with Tsuga , Quercus , Fagus , Pinus , 575 m, 29 Aug 2013, S.A. Trudell SAT1324109 (TENN 068871). Great Smoky Mountains National Park, Greenbrier, Injun Creek Trail, under Tsuga , 450 m, 18 Nov 2004, E.B. Lickey TFB12369 (TENN 060445). Great Smoky Mountains National Park, Cosby, Gabes Mountain Trail, with Tsuga and mixed hardwoods, 685 m, 16 Oct 2006, E.B. Lickey TFB13482 (TENN 061745). Big South Fork National River & Recreation Area, John Litton Farm Trail, scattered at base of dead Tsuga , in mixed woods with Tsuga , Quercus , Pinus , 425 m, 29 Oct 2017, R.A. Swenie RAS247 (TENN 073181).

Discussion.

Hydnum umbilicatum is widespread in eastern North America at low and high elevations, mostly in conifer-dominated forests or mixed woods including conifers. The macromorphology can vary dramatically among basidiomes with some specimens displaying the namesake umbilicate pileus while others do not. The presence of an umbilicus is not a unifying taxonomic feature as its presence has been observed in several distantly related clades of Hydnum . Peck (1901) included a color plate illustration with his description depicting basidiomes with thin, convex, umbilicate pilei and slender stipes that are slightly longer than the diameter of the pileus. Unfortunately, we were unable to obtain DNA sequences from the type collection. However, in comparison to other closely related clades, specimens of H. umbilicatum have slightly larger globose to subglobose basidiospores averaging 8.4 × 8 μm with average Q values below 1.08, which closely matches our spore measurements of the holotype. In addition, Peck mentioned that "sometimes a definite line separates the paler margin from the more highly colored center of the pileus", a trait that has been observed in several of the specimens of this species that cluster in a single ITS lineage.