Catillaria subviridis (Nyl.) Zahlbr. Cf.

     Thallus crustose relatively thick in places, rimose, beige, greenish-grey, becoming whitish when wet, matt, prothallus poorly defined and barely visible. Apothecia numerous sometimes grouped and then more or less deformed, at first included and punctiform then emerging and finally sessile, 0.1-0.3 mm in diameter, disc flat to rarely slightly convex, blackish-brown when wet, black when dry, margin irregular, persistent. Asci subcylindrical 45-60 x 10-16 µm with a thick I+ blue apex acording to the literature, 60-70 x 20-25 µm acording to our measurement. Paraphyses simple with a blackish-brown apex. Spores elliptical, 1-septate, 10-16 x 4.5-6 µm according to the literature, 13-16 x 6-8 µm according to our measurements. No pycnidia. Photobiont: Dictyochloropsis. No significant chemical color reactions. Nitrophilous species found in the mesic supralittoral zone on organic-rich rocks near Hydropunctaria (Verrucaria) maura, and seemingly associated with Hydropunctaria amphibia (see photographs).

_ Similar in appearance and difficult to differentiate in the field from certain species and forms of Catillaria that can venture to the seashore, such as: Catillaria chalybeia; Catillaria atomarioides; and Catillaria lenticularis, which have smaller spores.

N.B. This species was poorly defined by the authors due to the lack of a well-preserved reference herbarium sample; therefore, we have added [see Cf.] pending clarification.

N.B. Taxon still under study because it is possible that it is a Lecidella with spores abnormally septate once by a false septum due to a plasma bridge (pseudodiblastic spores).