Calycina alstrupii Suija & Motiejūnaitė, 2017

Suija, Ave & Motiejūnaitė, Jurga, 2017, Calycina alstrupii sp. nov. (Pezizellaceae, Helotiales), a new lichenicolous fungus from Norway, Phytotaxa 307 (2), pp. 113-122 : 119

Calycina alstrupii Suija & Motiejūnaitė , sp. nov.

MycoBank: MB#819298; Fig. 3

Diagnosis: — Calycina alstrupii differs from all known Calycina species by being lichenicolous on Lobaria pulmonaria and by the combination of 8-spored asci and comparatively small, (5–)5.8(–7) × (1.5–)2.03(–2.5) μm, ascospores.

Type:— NORWAY, Nord-Trøndelag county, Flatanger municipality, Dale Nature Reserve, 64°26’31.9”N, 10°58’14.901”E, elev. 20–200 m, on Lobaria pulmonaria growing on trunk of Alnus incana , 5 Aug 2015, J. Motiejūnaitė (holotype, BILAS-10761!); ibid, on Alnus, A. Suija (paratype, TU76273!)

GenBank accession nos. holotype (lab code Pz162): KY305095 (rDNA ITS), KY305097 (nuLSU), KY305099 (mtSSU) ; paratype (lab code Pz167): KY305096 (rDNA ITS), KY305098 (nuLSU), KY305100 (mtSSU)

Ascomata superficial, solitary or gregarious (two to five ascomata in clusters), sessile, growing mostly on the underside, rarely on the upper side (some ascomata of paratype) of Lobaria pulmonaria thalli, cream to yellowish to light orange (when young), translucent, slightly gelatinous; disc concave to plane, (0.24–)0.34(–0.47) mm (n=18), roundish to somewhat elongated and irregular in shape; receptacle cupulate, with margin distinct, becoming indistinct in mature ascomata, somewhat pubescent but without setae ( Fig. 3a, b ). Apothecial structures hyaline to slightly yellowish under microscope, inspersed with oil droplets. Ectal exciple distinct, hyaline, with some yellowish pigmentation, c. 25 μm wide, with elongated-prismatic cells (textura prismatica), the cells in outer part shorter, angular (textura angularis), hairs at the margin scattered, short, straight, obtuse at tips (hyphoid), I–, K/I–; without granules on the surface ( Fig. 3c ). Medullary exciple (hypothecium) hyaline, with elongated interwoven cells (textura prismatica - porrecta). Hymenium hyaline (upper part) to yellowish (lower part), c. 60 μm tall. Asci eight-spored, cylindrical to subcylindrical ( Fig. 3d ), narrowed towards base, arising from single septa without basal protuberances (observed in Congo red), (44–)55.3(–67) × (5–)5.7(–7) μm (n=13), pars sporifera (23–)28.6(–35) μm; ascus apex roundish, with apical thickening; ascus apical ring structure of the Calycina- type, turning blue in K/I ( Fig. 3e, f ); ascus wall surface CRB– or only slightly CRB+ blue in dead state. Ascospores uniseriate to biseriate in the ascus, hyaline, aseptate, ellipsoid, with apices attenuated at one or both ends ( Fig. 3d ), or obtuse, 2–3-guttulate, (5–)5.8(–7) × (1.5–)2.03(–2.5) μm (n=23), l/w=2–3.5; wall CRB+ blue in dead state. Paraphyses aseptate, simple, unbranched to bifurcate, apically not widened ( Fig. 3e ), c. 1–1.5 μm wide, not taller than asci, I–, K/I–, containing hyaline vacuolar bodies which are CRB+ blue. Anamorph unknown.

Etymology: — named in the memory of Vagn Alstrup, a dedicated Danish researcher of lichenicolous fungi.

Habitat and host:— found in Picea abies -dominated boreal rainforest. The ascomata are located on the convex, naked and non-tomentose parts, mainly on the underside, of Lobaria pulmonaria thallus. Both the upper- and undersides of the host thallus remain healthy and relatively undamaged at the site of infection. However, other parts of the same thalli show signs of senescence, are discolored and are covered by aggregations of green algae and goniocyst-type thalli of an unindentified lichen. These observations suggest that Calycina alstrupii is a parasymbiotic species.

Known distribution:—reported from only a single locality in Nord-Trøndelag county, Norway. However, taking into account the overall distribution area of the host, we would expect the new species to be more widespread, and suspect that it has been overlooked due to the fact that the ascomata develop mainly on the underside of the host thallus and there are no specific signs of infection on the upper side.

Figures

FIGURE 3. Calycina alstrupii (holotype, BILAS 10761). a, b ascomata on the underside of Lobaria pulmonaria thallus (scale in mm); c hyphoid-type excipular hyphae in K/I; d single ascus with ascospores and an ascospore in water; e asci and paraphyses pre-treated with K/I (c–e scale in μm); f Calycina-type apical apparatus observed in K/I.