PART 1

6. Isidia scattered on the surface of the thallus; on trees and rocks; throughout
the state .................................................................................................................... L. austroamericanum (Malme) Dodge
4. Lobes irregularly anastamosing, the margins thickened; isidia becoming granular;
scattered throughout Florida .........................................................................................................................L. milligranum Sierk
3. Thallus not wrinkled; throughout Florida.................................................................................... L. cyanescens (Rabenh.) Körber
2. Thallus not isidiate................................................................................................................................................................................ 7
7. Thallus smooth, not wrinkled............................................................................................................................................................ 8
8. Thallus not pitted .......................................................................................................................................................................... 9
9. Thallus blue-gray, lobes 1-5 mm broad; scattered throughout Florida ......................................... L. azureum (Swartz) Mont.
9. Thallus gray-brown, lobes 2-3 mm broad; Duval County?, reported by Sierk
on the basis of a Calkins collection..........................................................................................................L. juniperinum Tuck.
8. Thallus pitted; peninsular Florida ........................................................................................................... L. microstictum Vainio
7. Thallus wrinkled.............................................................................................................................................................................. 10
10. Spores acicular or fusiform ...................................................................................................................................................... 11
11. Spores acicular, 50-85 µm long; thallus gray; Sarasota and Seminole counties.................................... L. adpressum Nyl.
11. Spores fusiform, 25-40 µm long; thallus usually brownish; peninsular Florida
north to Levy County...............................................................................................................L. fusisporum (Tuck.) Dodge
10. Spores ellipsoid or subfusiform................................................................................................................................................ 12
12. Lobes distinct, not anastamosing........................................................................................................................................ 13
13. Thallus naked above, shiny, with large pustules; cited by Moore
from four counties, not found by me nor have I seen her material,
Florida records possibly equal the next species............................................................. L. corticola (Taylor) Tuck.
13. Thallus sparsely hairy above; hairs short with cylindrical cells; thallus naked
below, dull, with small pustules ................................................................................................ Leptogium sp. 31815
12. Lobes irregularly anastomosing .......................................................................................................................................... 14
14. Thallus heavily wrinkled longitudinally, lobes narrow and
elongate or inflated and hollow ................................................................................................................................ 15
15. Apothecia not at the ends of hollow lobes; cortical cells
usually more than 5 µm wide.............................................................................................................................. 16
16. Thallus thickened but not warty, generally appearing gray
or gray-green ................................................................................................................................................. 17
17. Thallus gray; thalloid exciple lobulate; scattered throughout
the state ................................................................................................... L. phyllocarpum (Pers.) Mont.
17. Thallus green or gray-green; thalloid exciple not lobulate;
scattered throughout the peninsula................................................................L. chloromelum (Ach.) Nyl.
16. Thallus warty, usually appearing bluish; north to Lake
and Seminole counties..................................................................................................... L. floridanum Sierk
15. Apothecia at the ends of elongate hollow lobes; cortical cell
usually less than 5 µm wide; peninsular Florida from Levy and
Marion counties south to Palm Beach County......................................................................L. stipitatum Vainio
14. Thallus wrinkled but flattened, lobes rounded; Lake, Polk and
Seminole counties ............................................................................................................................ L. sessile Vainio
1. Thallus small, appearing almost crustose; reported from Seminole County by Sierk ....................L. tenuissimum (Dickson) Körber
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