Figs 1-5. Besa papillaeformis, topotype material (Setchell #6485, UC173490). Figs 1-4. Habit of specimens borne on crust. Fig. 5. Ostiolar region (arrow) in cystocarpic upright.
Figs 6-10. Besa papillaeformis, topotype material (Setchell #6485, UC173490). Longitudinal sections through vegetative thalli. Figs 6-7. Uprights arising from crust surface. Figs 8-9. Crust composed of isodiametric and vertically elongated cell files, and secondary pit connection formation. Fig. 10. Dome-shaped bulges welling up from surface of crust.
Figs 11-14. Besa papillaeformis, topotype material (Setchell #6485, UC173490). Longitudinal sections through vegetative thallus; note abundant formation of secondary pit connections. Lower cells of upright are elongated, central medullary cells are loosely compact and slightly radiating thallus outward, small-celled cortical zone is composed of longitudinally concavo-convex divided surface cells.
Figs 15-19. Besa papillaeformis, topotype material (Setchell #6485, UC173490). Longitudinal sections through spermatangial thalli. Figs 15-16. Surface cells dividing by concavo-convex division into spermatangial parent cells. Figs 17-18. Branched spermatangial parent cells. Fig. 19. Elongate spermatangial parent cells with terminal spermatangia.
Figs 20-25. Besa papillaeformis, topotype material (Setchell #6485, UC173490). Female thalli. Figs 20-21. Grazed section showing scattered unfertilized procarps (arrows). Figs 22-25. Longitudinal sections. Fig. 22. Unfertilized procarps (arrowheads) buried in cortex. Fig. 23-24. Procarps consisting of supporting cell (su) bearing a 3-celled carpogonial branch [cb1=first cell, cb2=second cell, cp=terminal carpogonium with trichogyne (t)]; cb1 bears sterile cell (st). Fig. 25. Longitudinal section. Gonimoblast cells course across medullary region. Supporting cells of unfertilized procarps degenerate.
Figs 26-32. Besa papillaeformis, topotype material (Setchell #6485, UC173490). Longitudinal sections through cystocarpic thalli. Fig. 26. Young internal cystocarp in upright borne on crust. Figs 27-28. Young internal cystocarp centrally immersed in upright. Note absence of carpostomes in cortex and lack of specialized nutritive tissue in medulla. Fig. 28. Fusion of fusiform gonimoblast conjunctor cells (arrow) to vegetative cells (v), and partial fusion of gonimoblasts within same cell file (top). Fig 29. Stellate and stretched vegetative cells bearing gonimoblasts (g) that have become carposporangia. Fig. 30, Fig. 31. Mature cystocarp. Fig. 32. Excised carposporophytic network released together through ostiolar region leaving behind cavity.
Fig. 33. One of ten maximally parsimonious trees inferred from rbcL sequences from 51 Phyllophoraceae (Length = 1722, Consistency Index = 0.36, Retention Index = 0.6