Cortinarius langeorum Frøslev & T. S. Jeppesen, 2006

Frøslev, Tobias G., Jeppesen, Thomas S. & Laessøe, Thomas, 2006, Seven new calochroid and fulvoid species of Cortinarius, Mycological Research 110, pp. 1046-1058 : 1052-1053

Cortinarius langeorum Frøslev & T. S. Jeppesen , sp. nov.

MycoBank no.: MB 500730

( Figs 1D , 2D & 4D )

Etym.: langeorum (Latin), after the family Lange.

Pileo 50–100 mm lato, hemisphaerico, dein plano-convexo, glutinoso, primo luteo, dein a centro ochraceo-luteo vel brunneo, interdum centro e velo pallide virido-flavescenti maculato, in laesionibus safrano-ochrascenti, KOH ope brunneo, dein roseobrunneo. Velo universale virido-flavo, KOH ope obscuro roseobrunneo. Lamellis emarginatis, in juventute pallide eburneis, nec luteis. Stipite pallido, albido, non luteo, bulboso, bulbo distincte marginato. Margine bulbi e velo virido-luteo, KOH ope obscuro roseo-brunneo. Facie externa mycelioque lutea, KOH ope nullo. Velo partiale albido vel virido-flavo. Carne albida, interdum in apice stipitis pallide ochraceo-brunnea, sapore miti, odore subnullo, KOH ope nullo. Sporis limoniformibus, grosse verrucosis, 11-12.5 X 6.5-8 µm.

Typus: Denmark: Østjylland: Århusskovene , Jens Baeks Vedkast , under Fagus sylvatica, 15 Sep. 2000, T. G. FrØslev, TF2000- 012 ( C – holotypus)

Pileus 60–120(–140) mm, hemispherical then plano-convex, glutinous, glabrous, with age slightly innately fibrillose, at first yellow (2A4–2A5–3A4–3A5–4A6), soon becoming ochre–yellow (4B6–4B7) then brownish (4C7–5D7), margin remains yellow (3A4–3A5), often with veil remnants seen as pale greenish yellow to whitish patches, or sometimes as small brownish scales, where damaged often more or less saffron-coloured to red brown (7E7). Lamellae emarginate, greyish white to cream when young. Stipe 50–120 X 10–25 mm with a broad marginate bulb (– 45 mm), whitish. Bulbipellis and mycelium characteristically pale cream yellow to bright greenish yellow (1A3–1A4), bulb margin often bright greenish yellow from veil remnants. Cortina whitish to greenish yellow, fairly abundant. Veil pale greenish yellow to white. Context whitish, sometimes with a very pale greyish brown tinge in stipe apex, a thin greenish yellow line is seen in the lower bulb cortex when the bulbipellis is strongly coloured. Taste mild, indistinct, smell somewhat yeast-like (like many phlegmacioid species, e.g. C. saporatus ), sometimes with a faint curry component. Spores citriform, with distinct net-like ornamentation, 11–12.5(–13) X 6.5–8 µm, average 12.0 ± 0.5 X 7.1 ± 0.4 µm; Q ¼ 1.69 ± 0.07.

Chemical reactions: KOH on pileus at first brown (7E8), becoming deep red brown (8E8–9E8) after 2–3 min, on universal veil on bulb margin deeper red brown (9E8–10E8), in context and on bulbipellis negative.

Habitat: Known from temperate forests dominated by Fagus sylvatica on calcareous or mineral rich soil in Denmark and Sweden, almost always found in bare soil in erosion zones or on soils with a very thin litter layer.

Observations/Discussion: Cortinarius langeorum is distinguished from all other fulvoid (and calochroid) species by the lack of yellow colour on lamellae, context and stipe, a rather strong alkaline reaction on the pileus in combination with the characteristic yellow veil (seen as remnants on the bulb margin) and a pale greenish yellow bulbipellis. It is most similar to the less pigment rich fulvoid species ̅ i.e. C. humolens (syn. C. claroflavus sensu Moser ) and C. sulphurinus . The most similar species, C. humolens , differs in several respects. C. humolens has an earth-like smell, whereas C. langeorum has a neutral Phlegmacium- like smell, sometimes with a faint curry-like component. C. humolens has a weak alkaline reaction (negative to pale brownish) on the pileus, whereas C. langeorum reacts strongly brown to red–brown. Furthermore, C. humolens has yellowish colours on both lamellae and usually also on the stipe, where C. langeorum has colourless lamellae and stipe contrasting the yellow bulbipellis and veil remnants on the bulb margin. C. sulphurinus differs by the parsley-like smell, greenish yellow colours on the lamellae, stipe and context, and has a strong red alkaline reaction on the mycelial strands. C. flavovirens also has weak colours on the lamellae and in the context, but has a strong farinose smell and much smaller spores. Seen from above the pileus of C. langeorum oxidises in a way that makes it resemble more pigment-rich species (e.g. C. alcalinophilus , C. olearioides ), which all, however, have yellow context and lamellae. Due to the lack of colours in the context and lamellae, it seems possible that the species could have been treated in the section Multiformes or Calochroi – but no names published in these sections fit the species to our knowledge. Aberrant specimens of C. caesiocortinatus may show a certain resemblance, but are easily identified by the (sub-)globose spores. The illustration of C. sulphurinus in Flora Agaricina Danica ( Lange 1938) shows an expanded fruit body with brownish yellow colours on a pileus with velar patches. The original description of C. sulphurinus presents a more pigment rich species than the one collected and illustrated by Lange. Presently C. sulphurinus sensu Lange is widely perceived as a synonym of C. saporatus sensu Brandrud et al. ( Brandrud et al. 1989 – 1998) syn. C. subturbinatus . This interpretation, however, has to be rejected as the drawing of Lange clearly shows an agaric with bright yellow colours on the bulb. In the many years after Lange drew his plate C. saporatus has never been found on or near the locality of C. sulphurinus sensu Lange. Contrarily , C. langeorum has one of its localities there. Therefore, as both the macroscopic and microscopic features fits well with C. langeorum , we dare to postulate that C. sulphurinus sensu Lange has found its final interpretation. It has only been found in localities hosting several other rare species of phlegmacioid Cortinarius , and seems to be among the top ten rarest phlegmacioid species in Denmark. Although the species is well known to us and easily recognisable, we have never encountered the species in southern parts of Europe or with other hosts than Fagus sylvatica, nor in the literature. We have chosen to name our species after the family Lange, which has given us three generations of prominent figures in mycology, and especially as an appreciation of Jakob E. Lange’s monumental work on agarics. The species was included in the study of Frøslev et al. (2005) as C. neolangei ined. (TF2000-012, TSJ2003-078 and TSJ2003-057). An ITS sequence from the holotype of C. langeorum is available at GenBank (accession DQ083798 ).

Additional specimens examined: Denmark: Sjaelland: Allindelille Fredskov, Fagus sylvatica on calcareous soil, 4 Oct. 2003, T.S.J., TSJ2003-093 ; loc.cit., 20 Sep. 2004, T.G.F. & T.S.J., TSJ2004-011 ; loc.cit., 8 Oct. 2004, T.S.J. & T.G.F., TSJ2004-065 ; loc. cit., Lellinge Skovhusvaenge at Køge , F. sylvatica on mineral rich to calcareous soil, 19 Sep. 2003, T.S.J., TSJ2003-023 ; loc. cit., 25 Sept. 2003, T.S.J., TSJ2003- 057 , TSJ2003-058 ; loc. cit., 5 Oct. 2003, T.S.J., TSJ2003-098 ; Østjylland: Århusskovene , Jens Baeks Vedkast , F. sylvatica on mineral rich soil, 8 Oct. 1997, T.G.F. & T.S.J., TT1997-040 ; loc.cit., 16 Oct. 1999, T.S.J. & T.G.F., TSJ1999-089 ; loc. cit., TSJ 1999 -090 ; loc.cit., 3 Oct. 2004, T.S.J., TSJ2004-058 . ̅ Sweden: Skåne: Vittskövle , Herremöllan , F. sylvatica on mineral rich soil, 30 Sep. 2003, B. Hägg & T.S.J., TSJ2003- 078 ; loc. cit., TSJ2003-079 .

Figures

Fig 1 – Fruit bodies of the new species of Cortinarius. (A) C. albertii, TF2000-058 (holotype). (B) C. chailluzii, TSJ2000-085 (holotype). (C) C. cisticola, TSJ2002-081 (holotype). (D) C. langeorum, TF2000-012 (holotype). (E) C. sancti-felicis, TSJ2002-072 (holotype). (F) C. selandicus, TF2004-104 (holotype). (G) C. vesterholtii, TT1997-009 (holotype). Photographs A, D and G by T.G.F., B, C, E and F by T.S.J.

Fig 2 – Basidiospores. (A) Cortinarius albertii, TF2000-058 (holotype). (B) C. chailluzii, TSJ2000-085 (holotype). (C) C. cisticola, TSJ2002-081 (holotype). (D) C. langeorum, TF2000-012 (holotype). (E) C. sancti-felicis, TSJ2002-072 (holotype) (F) C. selandicus, TF2004-104 (holotype). (G) C. vesterholtii, TT1997-009 (holotype). (H) C. catharinae, TF2004-105. Scale bar = 10 Mm in each case.

Fig 4 – Fruit body habit of the new Cortinarius species. C. albertii, TF2000-058 (holotype). (B) C. chailluzii, TSJ2000- 085 (holotype). (C) C. cisticola, TSJ2002-081 (holotype). (D) C. langeorum, TSJ2003-057 (middle) and TSJ1999-089. (E) C. sancti-felicis, TSJ2002-072 (holotype). (F) C. vesterholtii, TSJ1999-039 (right) and TF2004-101. Drawn to scale. Scale bar = 1 cm in each case.