Diploschistes diacapsis

Thallus crustose, white, thick and lax, with convex and verrucose and pruinose areoles.

Reproduction: Apothecia 2-5mm; punctiform, urceolate to lecanorine, open at the end, with radiale striated margin and concave black disc. Asci 8-spored. Spores muriform, with 3-6 transverse and 1-2 longitudinal septa, first hyaline then turning green-brown, broadly ellipsoid, 20-40 x 9-17 µm.

Photobiont: Chlorococcoid.
Spot tests: K- or K+ yellow to red, C+ red, KC-, P-, UV-.
Chemistry: diploschistesic and lecanoric acids and orsellinic acid (minor).
Habitat: On carbonate soils or gypsum outcrops, in dry meadows. Also, in thymes on clay soils.
Distribution: Arid and semi-arid regions of all continents.
Position in classification: Graphidaceae, Ostropales, Ostropomycetidae, Lecanoromycetes, Pezizomycotina, Ascomycota, Fungi.

Locality data:
Ecology, geology: On soil, W28C Petric Calcisol and Haplic Calcisol.
Altitude: 242 m
Location: Tossal de Montllober, Massalcoreig-Seròs (Segrià)
Climate: Dry Continental Mediterranean (Tmm=15-16ºC, 337mm)
  

Source: https://www.biodiversitylibrary.org/page/8152386#page/242/mode/1up

Source: https://www.biodiversitylibrary.org/page/44219615#page/371/mode/1up

Etymology of names:

Diploschistes (Norman, Conat. Praem. Gen. Lich.: 20, 1852) from the Greek δίπλοσ-σχίζω, meaning "doubly divided”) we interpret that the author means that the spores have transverse and longitudinal septa, since it is detailed in the description of the species (see attached description). The epithet diacapsis, from the Greek διακαψής. We have not found the explanation for this designation in the bibliography, δια means "through" and κάψής could be derived from κάμψα meaning "box".

Source: http://linnaeus.nrm.se/botany/kbo/flyttas/ach/tz/l1626.html.en

Mariano Lagasca (1776–1839), was a Spanish botanist, writer and doctor. He was the director of the Royal Botanical Garden of Madrid. Lagasca sent Erik Acharius samples of lichens that he considered of interest, as is the case of a sample of Diploschistes diacapsis that has been designated as the lectotype of the species.

Bibliography:

• Fernández-Brime, S., 2012. Els líquens saxícoles i terrícoles del Parc Natural de Cap de Creus, amb un estudi filogenètic aplicat a la sistemàtica dels gèneres Diploschistes i Ingvariella.
• Index Fungorum https://www.indexfungorum.org/names/NamesRecord.asp?RecordID=1621
• Lumbsch HT. The Identity of Diploschistes Gypsaceus. The Lichenologist. 1988;20(1):19-24. doi:10.1017/S0024282988000052
• Nimis P.L., 2024. ITALIC - The Information System on Italian Lichens. Version 7.0. University of Trieste, Dept. of Biology, (https://dryades.units.it/italic), accessed on YYYY, MM, DD. for all. All data are released under a CC BY-SA 4.0 licence. https://italic.units.it/index.php?procedure=taxonpage&num=902
  
• Roux C, et al. 2020, Catalogue des lichens et champignons lichénicoles de France métropolitaine. 3e édition revue et augmentée (2020). Édit. Association française de lichénologie (AFL), Fontainebleau, 1769 p.