LEJEUNIA - Lichens of Belgium, Luxembourg and northern France

Lecidea siderolithica Müll. Arg.
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Belgium, Ard.: Stavelot, vallée de l’Amblève, rocher de Challe (G8.52), paroi siliceuse
fortement enrichie en métaux lourds, 8.1997, E. Sérusiaux s. n. (LG); ibid., 3.1998, M.
Minet, E. Sérusiaux & P. van den Boom (LG, hb van den Boom).
France, Ard.: Ardennes, bois de Fumay, le long de la route entre Fumay et Revin, paroi
schisteuse subverticale fortement ferrophile, 6.1967, J. Lambinon 67/345 (LG); ibid.,
7.1978 (excursion de l’Association Française de Lichénologie 1978), R. Iserentant &
E. Sérusiaux (LG, hb Iserentant).
These collections have been examined by the most distinguished specialist of
the genus Lecidea, Dr H. Hertel, and were found to be close to Lecidea siderolithica
Müll. Arg. Several anatomical details however bring them somewhat apart from
it, but no alternative name could be found. L. siderolithica belongs to the Lecidea
fuscoatra aggr. and needs further investigations; typical populations are known
from the British Isles, France and Germany (HERTEL, 1995: 171).
The rock substrate at both localities is strongly enriched with iron and
typical ferrophilous lichen communities develop: at the Rocher de Challe in
Stavelot, Acarospora sinopica is the dominant species while yellow Lecanora
are lacking; at the Fumay locality, Lecanora epanora is very abundant,
together with Acarospora sinopica, Lecanora handelii and L. subaurea. The
species is new for the area covered by the checklist.
Leiorreuma lyellii (Sm.) Staiger
Syn.: Phaeographis lyellii (Sm.) Zahlbr.
France, Pic.: Somme, au N d’Abbeville, forêt domaniale de Crécy, lots 35-37 (H21.41),
alt. 75 m, sur Carpinus dans une forêt, 7.2001, P. Diederich 15089 (h).
See comments under Phaeographis dendritica. New for the study area.
Leptogium byssinum (Hoffm.) Nyl.
Belgium, Mosan: Oret (près de Mettet), hameau de Coroy (H5.32), carrière de sable,
2.2003, J.-P. Duvivier (h) & D. Ertz 3040 (BR, LG, hb Diederich).
This species was known from a single Belgian locality in the Mar. district
(DIEDERICH & SÉRUSIAUX, 2000: 117), and is here reported as new for the Mosan
district. It covers a surface of 1-2 m 2 at the edge of a quarry, where it grows in
open grass vegetation over clay.
Leptogium teretiusculum (Wallr.) Arnold
Belgium, Ard.: Villers-Sainte-Gertrude, au N du village, vallée du ruisseau de Pont-le-
Prêtre (H7.13), sur Juglans, dans un pâturage, 4.2001, E. Sérusiaux s. n. (LG).
This species was known from five Belgian and two Luxembourg saxicolous
collections (SÉRUSIAUX et al., 1999). The new record is most interesting, as it is
the first corticolous population in the study area.