Hydropunctaria orae Cf. Orange

    Thallus superficial, most often regular circle-shaped, 5-10 cm diam., 0.04-0.1 mm thick, cracked, notably towards the center, forming an incomplete network partly delimiting incomplete areoles, only visible when dry or on herbarium specimen, surface smooth or minutely warted, warts 20-40 µm high, clustured (dirty marks-like), greenish, grey-greenish, olive-green greyish, prothallus absent except in some young specimen (and not forming mosaics) and then whitish to very pale brown, dark green pigment present within pseudo-cortex (visible under magnification lens in the thallus cracks). Perithecia little prominent, 0.3-0.8 mm diam., apex rounded, blackish. Ascii 50-65 x 25-30 µm according to our measures. Ascospores oblong, simple, 15-18 x 7-8 µm according to literature, 15-17(19) x (6)7-8(9) µm according to our measures. Chemical spot tests negative. Raher rare. On rocks, at high tide level of greater ranges, in locations mainly shaded and subjected to brackish water inputs, often together with the black and much more common Hydropunctaria maura. This crypto-species was recently identified by means of molecular analyses. The other isolated crypto-species is  Hydropunctaria oceanica of which the thallus is thin, partially cracked, but with a colour similar to the one of Hydropunctaria maura and up to now distinguishable only throuh molecular maker analysis. For the following photographs we propose here the name of Hydropunctaria orae subject to the validation and reliability of the characters currently retained for this identification, in particular the greenish color and the general appearance of the thallus. This study is in progress but already for comparison an identification by biomolecular analyzes was carried out with typical samples by Tony ROBINET at the MNHN laboratory in Concarneau see Hydropunctaria orae ss. str. and it seems that some photographs correspond to an unknown species not described and whose sequence has not been deposited.

ORANGE A.  Semi-cryptic marine species of Hydropunctaria (Verrucariaceae, lichenized Ascomycota) from north-west Europe. The lichenologist. 44 (3) : 299-320 (2012).*