Flora of New Zealand Series

Mycelium growing between layers or groups of algal cells. Ascocarps solitary or gregarious, subglobose, immersed or erumpent, ostiolate, epapillate, coriaceous, top and base dark brown, sides hyaline or dark, ostiolar canal periphysate and with a turgid pulvillus. Paraphyses absent, centrum with or without a gelatinous matrix enclosing the asci. Asci 8-spored, clavate, pedunculate, unitunicate, at first thick-walled, finally deliquescing, developing along the inner wall of the ascocarp up to the ostiolar canal. Ascospores ellipsoid to ovoid, simple, colourless. Pycnidia solitary, subglobose, to lentiform, immersed, irregularly chambered, ostiolate, coriaceous, top and base brown, sides hyaline. Coniodiophores conical or cylindrical, simple. Conidia filiform or subglobose, simple, hyaline. Hosts: Marine algae (Chlorophyta).

Turgidosculum is a genus of two species of marine fungi forming mycophycobioses or obligate symbiotic associations with marine macroalgae (species of Prasiola) in which the habit of the alga dominates. The chlorophytes Prasiola borealis and P. tesselata are associated with ascomycete T. complicatulum. Hyphae grow throughout the algal thallus and separate it into groups of cells. These groups consist of tetrads or rows of algal cells. Large dark ascocarps and smaller pycnidia are embedded in this thallus, giving it a watery appearance. The question is still unresolved whether T. complicatulum is a symbiont or a parasite [Kohlmeyer and Kohlmeyer "Marine Mycology. The higher fungi", p. 77 (1979)]. In lichen literature this association is often treated as the lichen Mastodia tessellata (J.D. Hook. et Harvey) J.D. Hook. et Harvey ex J.D. Hook.; see Dodge [ Rep. B. A. N.Z. Antarctic Res. Exped. B, 7: 56-59 (1948)] and Brodo [ Bryologist 79: 396-399 (1976)]. One species is known from New Zealand.