Constrictolumina Aptroot, M.P. Nelsen & Lücking in Lücking et al., Lichenologist 48: 756 (2016).

MycoBank number: MB 816872; Index Fungorum number: IF 816872; Facesoffungi number: FoF 08795; five morphologically defined species (this paper); molecular data available for two species (Lücking et al. 2016).

Lichenized on bark in terrestrial, chiefly lowland to lower montane tropical habitats. Thallus ecorticate, usually whitish. Photobiont Trentepohlia. Ascomata solitary to rarely aggregate, erumpent to prominent, carbonaceous, ostiolate, ostiole apical to rarely lateral. Involucrellum carbonized. Excipulum prosoplectenchymatous, brownish to colorless below. Hamathecium comprising ca. 1 µm wide, hyaline, straight, branched and anastomosing, pseudoparaphyses, embedded in a gelatinous matrix. Asci 4–8-spored, bitunicate, fissitunicate, clavate, short pedicellate, with a non- amyloid ocular chamber. Ascospores irregularly arranged to biseriate, fusiform-ellipsoid, hyaline, 1–3-septate, euseptate, with secondary constrictions in each cell and often with slightly thickened walls, smooth-walled, slightly constricted at the septum, with a gelatinous halo, rather small (15–30 × 5–11 µm). Pycnidia unknown.

Chemistry: no substances detected by TLC.

Type species: Constrictolumina cinchonae (Ach.) Lücking, M.P. Nelsen & Aptroot in Lücking et al., Lichenologist 48(6): 756 (2016).

Notes: This genus was recently introduced for lichenized species of Arthopyrenia sensu lato with secondary cell wall constrictions clustering within Trypetheliaceae (Aptroot and Lücking 2016; Lücking et al. 2016). At the time, it was already noted that the species formed two lineages, C. malaccitula coming out separate. A phenotype-based phylogenetic binning approach of 11 species included in the genus demonstrated that about half of them each cluster with either with notable differences in the ascospores, those of the C. malaccitula group being mostly larger [(20–)30–50 × (7–)10–16 µm)], with more distinct secondary constrictions, and granular ornamented. We therefore introduce the genus Macroconstrictolumina for this group below. Constrictolumina in a strict sense then retains five species, which are keyed out below.


  • Constrictolumina cinchonae