Pachypeltis insularis (Poelt) Vondrák & I.V.Frolov

Vondrák, Jan, Frolov, Ivan, Davydov, Evgeny A., Yakovchenko, Lidia, Malíček, Jiří, Svoboda, Stanislav & Kubásek, Jiří, 2019, The lichen family Teloschistaceae in the Altai-Sayan region (Central Asia), Phytotaxa 396 (1), pp. 448-450 : 448-450

Pachypeltis insularis (Poelt) Vondrák & I.V.Frolov , combinatio nova

MycoBank: MB826776

Fig.: 7B.

Basionym: Caloplaca insularis Poelt in Planta 51: 300–301 (1958). Type:—[ FRANCE]. Westalpen: Dept. Htes Alpes, Montagne de Chaillol über dem Col du Lautaret, um [altitude] 2300 m, über schiefrigem Gestein [on schist, lichenicolous on calcicolous Aspicilia ] 8. 1957, Georges Clauzade & Josef Poelt (holotype M; currently not available).

Taxonomy: The type specimen was not seen, but we studied a topotype collected and identified by J. Poelt and deposited in GZU: “Südosthänge des Grand Area, NNW of Briancon, altitude 2300 m, on limestone, lichenicolous on Aspicilia , 11 July 1970 ”. The topotype morphology and the description ( Poelt 1958), both clearly indicate that Caloplaca insularis belongs to Pachypeltis : thallus squamulose forming tight spots on host thalli, apothecial disc brown and rough, apothecial margin thick, medulla and part of the cortex at base of squamules amyloid (I+ blue). The topotype and a few other specimens from the Alps (deposited in GZU) are almost identical with specimens from the Altai-Sayan region, but the latter tend to form larger and thicker spots on the host thalli.

Geographic note: New to Greece from Mt Olympus (specimen Frolov 1671), see Table 1 for details.

4 localities at altitudes 1750–2900 m, in arid alpine habitats, but a single record from humid alpine site. Substrate: limestone, lichenicolous on Aspicilia .

Pachypeltis intrudens (= Caloplaca infestans ), Fig. 7C : 3 localities at altitudes 1530–2900 m, in arid alpine class. Substrate: siliceous rocks or limestone; lichenicolous on various lichen crusts.

Caloplaca infestans was described by Magnusson (1944) from Mongolia (syntype L 3406 in S!) and Caloplaca intrudens (= Pachypeltis intrudens ) was described by Magnusson (1940) from Gansu, China (Syntype L 2604 in S!). Magnusson distinguished Caloplaca infestans from Caloplaca intrudens by smaller apothecia, less lax paraphyses and larger ascospores with broader septa. Our measurements in the specimen Vondrák 18059 revealed large differences in ascospore sizes and thickness of septa among three measured apothecia: (1) ascospores (14‒)14.8(‒15) × (8‒)8.1(‒8.5) μm, septum 4.5‒6 μm; (2) (13‒)14.4(‒17) × (7‒)7.4(‒8) μm, septum 3‒5 μm; (3) (12.5‒)14.2(‒15.5) × (6‒)7.5(‒8) μm, septum 4‒5 μm. Spore characters observed in our specimen overlap with values characterizing both Magnusson’s species: ascospores 12‒13 × 5.5‒6.5 μm with septa 3‒3.5 μm in C. intrudens and 13‒15 × 8.5 μm with septa 4‒5 μm in C. infestans . Type specimens of both species are lichenicolous on epilithic crustose lichens without differences in external appearance. The names are considered synonyms here, and the epithet intrudens has priority.

Figures

FIGURE 7. ‘Caloplaca’ anularis group (A) and Pachypeltis (B–E). A, ‘Caloplaca’ cf. bohlinii (Vondrák 18251) distinguished from ‘C.’ anularis by orange thallus with more frequent apothecia; B, Pachypeltis insularis (Vondrák 10340); C, Pachypeltis intrudens (Vondrák 18059); D, Pachypeltis cf. pachythallina (large squamules) on Calogaya (Vondrák 12649); E, Pachypeltis phoenicopta (Vondrák 18695) having deep orange pycnidia contrasting with pale yellow colour of thallus; F, detail of areoles of P. phoenicopta (Vondrák 18695) showing patches of white pruina that gives the typical pale yellow colour to the thallus.All bars, 1 mm.