Malmidea eeuuae

Malmidea eeuuae
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Lecanoromycetes
Order:	Lecanorales
Family:	Malmideaceae
Genus:	Malmidea
Species:	M. eeuuae
Binomial name
Malmidea eeuuae Kalb (2011)
Holotype: Khao Yai National Park, Nakhon Ratchasima province, Thailand

Malmidea eeuuae is a corticolous (bark-dwelling), crustose lichen in the family Malmideaceae. It was described in 2011 from Khao Yai National Park in north-eastern Thailand. The species has a finely warted thallus and non-septate, halonate ascospores, and it differs from M. coralliformis by its larger spores.

Taxonomy

The species was introduced as Malmidea eeuuae by Klaus Kalb in 2011 within a study on Malmidea and the family Malmideaceae. The holotype was collected in a very disturbed tropical rainforest near the students' lodges (Ban Krong Kaew) in Khao Yai National Park, Nakhon Ratchasima province, at about 760 m elevation. The specific name honours Jutarat Sutjaritturakan ("Eeuu"), a Thai lichenologist.

Description

The thallus is thin, crust-like and continuous (about 150–200 μm thick) on bark, densely warted (verrucose) with warts 0.1–0.15 mm high and 0.1–0.25 mm wide; soredia and isidia are absent. The medulla is cream-coloured and reacts potassium hydroxide (KOH)-positive (dark orange to orange-red). The photobiont is chlorococcoid (cells 5–8 μm in diameter). Apothecia are sessile, rounded to slightly flexuose, 0.2–0.5 mm across and 0.1–0.2 mm high; the disc is plane to slightly convex and light leather-brown to tawny, with a thin biatorine margin of the granifera type that starts entire and prominent but becomes slightly recurved and warty; the margin is 80–130 μm thick and whitish to cream. The proper exciple is hyaline at the periphery and internally shows a medullary layer of loosely arranged, periclinal hyphae with constricted septa, 30–50 μm wide, bearing yellowish to ochraceous-yellow hydrophobic granules that partly dissolve in KOH with a yellowish to greenish-yellow reaction. The subhymenium is about 50 μm high and chocolate- to olive-brown; the hypothecium is 50–75 μm high, brown and K–; the hymenium is 100–120 μm high and hyaline. Asci measure 55–70 × 16–20 μm. Ascospores number 4–6 (more rarely up to 8) per ascus, are colourless, ellipsoid, non-septate and halonate, typically 16–20 × 8–11 μm with a 1–1.5 μm halo. Reported chemistry includes xantholepinone G (major), contortin (submajor), concontortin (minor) and three unknown xantholepinones (minor).

Habitat and distribution

Known from Khao Yai National Park, Malmidea eeuuae grows on tree bark in very disturbed tropical rainforest around 760 m elevation, near the students' lodges at Ban Krong Kaew.

References