Dacampia rhizocarpicola (All Fungi)
Anamorph: unknown.
Teleomorph: Ascostromata formed in shallow cavities within the host thallus, 700–950 µm diam, perithecial, shallowly domed to subglobose, 1- to 2-loculate, the base ± flat, the ostioles minute and not papillate, the upper part pale grey-brown, darker at the base and with amorphous melanized material deposited around the ostioles. Ascostromatal wall thick (to ca 50 µm), composed of a thick inner layer of rather amorphous cells intermediate between textura angularis and globulosa in form, and an outer layer of similar cells with more extensive melanin deposits. Interascal tissue composed of copious many-septate cellular pseudoparaphyses 2–2.5 µm in diam, anastomosing at the base, apparently lacking a distinct mucous coat although the hymenium as a whole is strongly gelatinized. Asci formed from croziers, 116–146 (–164) × 21–24 µm, narrowly clavate, fairly long-stalked, thick-walled and fissitunicate, the apex rounded with a well-developed ocular chamber, 2- (to 4-) spored. Ascospores 28–36 × 15–16.5 × 13–14.5 µm, rather variable in shape (possibly due to differences in maturity) but usually cylindric-ellipsoidal, laterally flattened, muriform, golden to dark brown. Primary septum transverse, slightly constricted and only slightly submedian, with four secondary transverse septa, the cells immediately each side of the primary septum with two or three equally spaced longitudinal septa (thus dividing into two or three cells), the intermediate cells with two septa and the end part aseptate. Ascospore wall minutely verrucose, with a thin gelatinous sheath ca 1 µm thick.
This species is only known from a single collection made in 1989, and despite extensive field surveys for lichenicolous fungi in general in the region from where it is known, it has not been rediscovered. Its collection locality is not known in detail, which makes monitoring more difficult. It must be provisionally regarded as endangered.
Recorded from a lichen identified as Rhizocarpon obscuratum (Ach.) A. Massal. This name has been used for two species in the UK, now referred to as R. lavatum (Fr.) Haszl. and R. reductum Th. Fr. (Smith et al., 2009). The host lichen is degenerated and its identity is not certain, but the pale brown thallus and ascomata that tend to be umbonate points towards the former species.
Only known from Scotland (Angus).