Leccinum in Costa Rica

Key to Leccinum

The most diagnostic feature of the genus is the presence of a conspicuous stipe ornamentation in the form of scabers or semi-recurved scales. This ornamentation becomes pigmented with maturity and ranges from yellow (L. andinum), pink (L. cartagoense) to brown/black (remaining taxa). This feature is best seen in the image of L. monticola. There are seven species of Leccinum currently recognized from Costa Rica, although some boletologists would place L. eximium and L. cartagoense in Tylopilus because these taxa produce pinkish flesh colored spore deposits rather than deposits with olivaceous to umber or cinnamon brown colors.
Interactive key

Vouchers for all collections are on deposit at the Universidad de Costa Rica (USJ) mycological herbarium or Instituto Nacional de Biodiversidad (INB). Duplicates are in the Field Museum (F) and the New York Botanical Garden (NY).

1. Hymenophore yellow, bluing when injured . . . . L. andinum Halling
1. Hymenophore rarely yellow, NEVER bluing when injured

2. Pileus rugulose during some stage of development

3. Context becoming pink to reddish orange in the pileus and upper part of the stipe when exposed

4. Context changing to pink in the pileus and deep blue in the lower half of the stipe; stipe scabers dark gray to black . . . . L. talamancae Halling, Gómez, & Lannoy
4. Context not changing to blue green or dark blue in the lower half of the stipe; stipe scabers caramel colored to light brown . . . . L. rugosiceps (Peck) Singer

3. Context unchanging

5. Pileus dark reddish brown; hymenophore yellow; stipe scabers tan to gray brown; stipe surface developing some red or yellow tones . . . . L. neotropicalis Halling
5. Pileus light gray brown to tan; hymenophore white to orangish white; stipe scabers gray to black; stipe surface white . . . . L. tablense Halling & G. M. Mueller

2. Pileus even throughout development

6. Stipe with pink scabrosities on white ground color over upper part, chrome yellow at the base . . . . L. cartagoense (Wolfe & Bougher) Halling & G. M. Mueller
6. Stipe with dark colored scabers (brown to black), never chrome yellow in the base

7. Pileus orange brown to red brown, with sterile flap at margin; stipe white with brown to black scabers . . . . L. monticola Halling & G. M. Mueller
7. Pileus violet brown to chocolate brown, lacking sterile flaps; stipe pale violet with brown scabers . . . . L. eximium (Peck) Singer

The most diagnostic feature of the genus is the presence of a conspicuous stipe ornamentation in the form of scabers or semi-recurved scales. This ornamentation becomes pigmented with maturity and ranges from yellow (L. andinum), pink (L. cartagoense) to brown/black (remaining taxa). This feature is best seen in the image of L. monticola. There are seven species of Leccinum currently recognized from Costa Rica, although some boletologists would place L. eximium and L. cartagoense in Tylopilus because these taxa produce pinkish flesh colored spore deposits rather than deposits with olivaceous to umber or cinnamon brown colors.	Interactive key

Vouchers for all collections are on deposit at the Universidad de Costa Rica (USJ) mycological herbarium or Instituto Nacional de Biodiversidad (INB). Duplicates are in the Field Museum (F) and the New York Botanical Garden (NY).