Cortinarius sect. Olorinati Soop & Dima, 2020

Dima, Bálint & Soop, Karl, 2020, The ‘ xenosmatoid’ group of Cortinarius (Agaricales) in New Zealand, Phytotaxa 438 (4), pp. 223-236 : 232-234

Cortinarius sect. Olorinati Soop & Dima , sect. nov.

Type: C. olorinatus E. Horak in Horak & Wood (1990: 92).

MycoBank MB 833327

Description:— Basidiomata myxacioid or phlegmacioid, small to medium, viscid. Pileus 25–40 mm diam., white to yellow-brown. Lamellae white to pale yellow. Stipe ± viscid to dry, whitish with or without bulbous base. Universal veil white, sparse. Alkaline reaction reddish or insignificant. Basidiospores ellipsoid, 7.5–10 × 4.5–5 µm, moderately verrucose. In Nothofagaceae forest, New Zealand and South America.

Comments:—The section appears as sister to sect. Vibratiles. The type species was described in subg. Myxacium (Fr.) Trog. (1944: 42) ( Horak & Wood 1990), while C. cf. dulciorum has a more phlegmacioid habit with a dry, bulbous stipe. Unfortunately, no morphological data are available for C. cf. xenosma , whose single collection ( OTA 60162) was labelled ‘ C. xenosma ’. The unnamed South American species were included in Truong et al. (2017), but without description. In addition, a separate check shows that at least two unnamed species from New Caledonia ( ITS in GenBank KY 774115 and KY 774172; cf. Carriconde et al. 2019) may belong to the section (data not shown). Currently included species with their known provenance: C. olorinatus (NZ) , C. cf. dulciorum (NZ) , C. choloides (SAm), C. cf. xenosma (NZ) , Cortinarius sp. I (SAm), Cortinarius sp. II (SAm), Cortinarius sp. III (SAm).

Key to the xenosmatoid Cortinarii of New Zealand

General characters are mentioned in the Introduction.

1. Pileus viscid, stipe with a marginate bulb ................................................................................................................... C. myxenosma

- Pileus dry, stipe cylindrical or with a small rounded bulb .................................................................................................................2

2. Basidiomata robust, stipe mostly> 7 mm at apex...............................................................................................................................3

- Basidiomata small, stipe slender ........................................................................................................................................................6

3. Lamellae with a blue to violet tinge ...................................................................................................................................................4

- Lamellae pale greyish to pale grey-brown .........................................................................................................................................5

4. Pileus mahogany red with a red alkaline reaction, basidiospores <9.3 µm long.......................................................... C. cupreonatus

- Pileus purple brown, alkaline reaction trivial, basidiospores larger........................................................................... C. trichocarpus

5. Stipe, universal veil, and/or context slightly reddening with age, many basidiospores>7.5 µm long, weakly verrucose, almost smooth .............................................................................................................................................................................. C. xenosma

- Stipe, universal veil, and/or context with distinctly red to rosy zones, basidiospores shorter, moderately verrucose......................... ................................................................................................................................................................................... C. paraxenosma

6. Lamellae yellow-brown, basidiospores subglobose ...........................................................................................................................7

- Lamellae red-brown, basidiospores ellipsoid.......................................................................................................... C. xenosmatoides

7. In Nothofagaceae forest, alkaline reaction red on cutis and universal veil ........................................................................ C. caryotis

- In Myrtaceae forest, alkaline reaction trivial................................................................................................................... C. minilacus