Tuber pustulatum – Sociedad Ibérica de Micología

Tuber pustulatum M. Leonardi, A. Paz, G. Guevara & Pacioni, Mycologia 111 (4): 682. 2019.

MycoBank MB828722

Author: PAZ A.

Taxonomic classification

phy Ascomycota

sbp Pezizomycotina

cls Pezizomycetes

sbc Pezizomycetidae

ord Pezizales

fam Tuberaceae

gen Tuber

sp Tuber pustulatum

Description

Ascomata globose to slightly lobed, sometimes with a basal cavity, surface when young with pinkish tones and ferruginous when mature, reddish brown. Surface covered with polygonal, truncate warts. Smell acid, intense, slightly unpleasant. Peridium thick, 370-550 μm, formed by a) a pseudoparenquimatous external layer (exoperidium), 160-220 μm thick, with subglobose, irregular or polygonal cells, mostly 17-23 x 13-18 μm, thick-walled (up to 4 µm), pale yellow to pale brown, aggregated in polygonal, truncate warts, 350-400 μm high and 0,18-1,1 mm broad at the base, visible on the ascoma surface, que se aprecian en la superficie del ascoma; and b) an internal layer (endoperidium), often bistratified, 210-350 μm thick, with cells progressively diminishing in size, around 7-12 x 4-9 μm, hyaline, thin-walled, sometimes, with skeletal hyphae mixed with globose cells underneath the gleba. Gleba with scarce sterile venae, gelatinized and branched, hyaline and contrasting over the fertile part, which is pinkish when young, and brown when mature, with hialine hyphae mostly 4-8 μm broad, swollen at their terminal up, up to 10-14 μm. Asci ellipsoid to subglobose, 80-120 x 72-85 μm, with the wall 1-1.5 μm thick and a forked stalk at the base, 30-45 x 7-12 μm, containing 1-6 ascospores. Ascospores coloured, spiny-reticulate, ovoid, often apiculate, sometimes ellipsoid, 27.45 ± 5.7 x 22.63 ± 4.55 μm, Q= 1.22 ± 0.3 (excluding ornamentation), with erect spines 3.5-7.0 μm high, united at the base by a low, well defined reticulum.

Ascospore size depends on the number of ascospores per ascus:

1 ascospore: 34-46 x 29-37 μm;

2 ascospore: 29-43 x 23-34 μm;

3 ascospore: 21-39 x 19-30 μm;

4 ascospore: 20-32 x 18-28 μm;

5 ascospore: 18-29 x 16-19 μm;

6 ascospore: 21-25 x 16-19 μm.

Growth habit, habitat and distribution: Growth generally disperse or in small groups and in different habitats. The holotype collection was made in Cantabria under Corylus avellana, but other collections were made under Fagus sylvatica, Betula pendula, Populus canadiensis, Quercus ilex, Quercus pyrenaica, Pinus sp., and Abies alba. Its distrubution area ranges between Spain, France and the Balcans.

References in our territory

Leonardi, M; Paz-Conde, A; Guevara, G; Salvi, D; Pacioni, G. 2019. Two new species of Tuber previously reported as Tuber malacodermum. Mycologia. 111(4):676-689

Specimens in scientific collections

* sequenced material

Reference specimen marked in bold

IC: private herbarium of A. Paz

Co: IC04121501

S: BCN-myc IC10011503* holotipo (isotipo: AQUI 9725*); IC02111506* (duplicado AQUI 9726*); IC22121301* (duplicado AQUI 9727*); IC06121403; IC01011706; IC12121607