Fleshy Fungi of New Brunswick >> Lactarius trivialis

Lactarius trivialis (Fr.) Fr.

Scattered (3) in leaf litter in mixed forest of Acer saccharum, Betula allegheniensis, B. papyrifera, Abies balsamea and Populus tremuloides, Nepisiguit Protected Natural Area, New Brunswick (16-08-16/01).

Basidiospores broadly ellipsoidal, amyloid, 7.8-9.6 X 6.4-8.0 μm (height of ridges not included), D/d = 1.13-1.34 (average[27]: 8.7 X 7.1 μm, D/d = 1.22), with ornamentation composed of short lines and ridges up to 1.3 μm high, with ridges occasionally branched or connected but never forming a reticulum. Pileipellis an ixotrichoderm 90-106 µm deep. Stipitipellis an ixotrichoderm 30-40 µm deep.

Lactarius affinis Peck, frequently reported in North America, is very similar and can be distinguished from L. trivialis only when young fruiting bodies are available. These are dark purplish to wine-red at first in L. trivialis but more tan to orange-brown in L. affinis. Since L. affinis was described from North America and L. trivialis from Europe there may be some justification for using the latter name with trepidation here. Genetic studies using collections from both continents are needed.

Photo: D. Malloch (16-08-16/01).