Thelotrema paralbidum Riddle

• Authority

  Britton, Nathaniel L. & Millspaugh, Charles F. 1920. The Bahama Flora.

• Family

  Graphidaceae

• Scientific Name

  Thelotrema paralbidum Riddle

• Description

  Species Description - Thallus epiphloeodes crustaceus uniformis effusus haud limitatus, sordide albidus, in crassitudine mediocris, rimoso-areolatus areolis subquadrangularibus 0.6-1.0 mm. latis inaequalibus vel leviter eonvexis. Gonidia chroolepoidea. Apothecia approximata aut partim dispersa, areolis thallinis immersa haud verrucas formantia, suborbicularia 0.5-0.8 mm. lata, disco aperto piano albissimo farinoso, superficiem thalli subaequante aut paullum submerso, margine duplice crenato aut sublacerato parum prominente; intus hyalino. Paraphyses simplices. Asci clavati, 8-spori. Sporae incolores ovideae murali-divisae, 8-10- loculares, loculis cubicis 2-3-locellatis, 22-25 X 9-11 µ.

• Discussion

  On bark, Maidenhead Coppice, New Providence (Elizabeth G. Britton, February, 1905, 323J,, type). Thelotrema paralbidum is externally similar to Ocellularia albida (Nyl.) Riddle, (Thelotrema albidum Nyl. Act. Soc. Sci. Fenn. 7: 451. 1863), but differs in sporecharacters. It is, perhaps, most closelv related to T. velatum Muell. Arg. (Bull. Soc. Roy. bot. Belg. 321 : 26. 1894), but differs in the thicker, areolate thallus, the white disk, and the shorter spores.