Gliophorus europerplexus Dentinger, A.M.Ainsw., & P.F.Cannon

Ainsworth, A. Martyn, Cannon, Paul F. & Dentinger, Bryn T. M., 2013, DNA barcoding and morphological studies reveal two new species of waxcap mushrooms (Hygrophoraceae) in Britain, MycoKeys 7, pp. 45-62 : 51-53

Gliophorus europerplexus Dentinger, A.M.Ainsw., & P.F.Cannon sp. nov. Figures 4-6

Holotype.

UNITED KINGDOM. Wales. Pembrokeshire (vice county 45): Hundleton, Somerton Farm, 51°39.88'N, 4°59.54'W (Nat. Grid Ref. SM931004), 11 Oct 2012, D.J.Harries DJH064B WX664 (K(M)181246)

Description.

Pileus 10-25 mm diam., hemispherical to conical or campanulate, sometimes with incurved margin, becoming plano-convex or remaining broadly conical, often umbonate, sometimes with irregular, lobed outline, margin faintly to strongly translucently striate to half-way, viscid or at least very lubricous, sometimes partially flared, at first usually pink-brown to orange-brown (brick, rusty tawny to fulvous), margin paler sometimes with orange (sienna to apricot) tints, hygrophanous, dried pilei dull orange (saffron to rust). Lamellae ventricose, mostly narrowly to broadly adnate with some slightly decurrent elements, intervenose, concolorous with pileus near pileal attachment, becoming paler towards free edge. Stipe 12-60 × 2-8 mm, cylindrical or compressed, sometimes with clavate base, hollow, sometimes flexuose, viscid but usually slightly less so than pileus, apically concolorous with pileus, paler below, sometimes basally tinted orange (apricot). Dried lamellar trama (lens) often darker than subhymenium and lamellar surfaces. Green pigments entirely absent. Without distinctive taste or smell, although one specimen [K(M)181241*] was noted to have a faint rubbery smell reminiscent of Gliophorus laetus . Spores [70, K(M)181241*, K(M)181245*, K(M)181246*] (6.5 –)7.0– 9.0 × (4.0 –)4.5–5.5(– 6.0) µm, per-basidioma mean values 7.5-8.0 × 5.0 µm, Q=1.3-1.8, mean 1.6, short-ellipsoidal to ellipsoidal, not constricted. Basidia predominantly 4-spored, clavate with attenuated base, (30 –)34– 57 × 5-9 µm excluding sterigmatal length (3.0-7.0 µm). Clamp connections on basidia, within lamellar trama and pileipellis usually normal, occasionally with conspicuously looped hook cells (medallion clamps). Lamellar trama subregular, compartments 20-120 × 4-21 µm. Stipitipellis and pileipellis are ixotrichoderms.

Distribution.

Identified from two sites in west Wales (Merionethshire and Pembrokeshire) supported by DNA sequence data. Fruiting was probably observed at the type locality by D.J. Harries on 6 August 2009 but no material was kept.

Ecology.

In unimproved short acid-neutral rough pasture in Merionethshire and found fruiting on bare soil near mosses on an almost vertical south-facing earth bank on farmland in Pembrokeshire.

Etymology.

Named to distinguish this European taxon from the morphologically similar Hygrophorus perplexus A.H.Smith & Hesler, a species with North American type material.

Conservation status.

Initially, it seemed likely that historic British collections assigned to Hygrocybe psittacina var. perplexa would be redetermined as Gliophorus europerplexus following DNA sequencing. However, two specimens filed in K under the former name yielded distinct ITS sequences (Fig. 1). Therefore, the distribution of Gliophorus europerplexus is currently unknown and it should be assessed as Data Deficient.

Other specimens examined.

United Kingdom. Wales. Merionethshire (vice county 48): Croesor, Cnicht, 52°58.34'N, 4°0.22'W (Nat. Grid Ref. SH64 but estimated to be SH655435 for conversion to latitude and longitude), 11 Oct 2011, E.J.M.Arnolds WX359 (K(M)181241*). Pembrokeshire (vice county 45): Hundleton, Somerton Farm, 51°39.88'N, 4°59.54'W (Nat. Grid Ref. SM931004), 19 Aug 2012, D.J.Harries DJH064A WX663 (K(M)181245*; immature).