PART 1

7. Ascospores narrower, with pointed ends, 42-53(-61)
× (7-)8-11(-12) µm, 8(-10)-celled; eastern Florida,
Citrus to Dade County .................................................................................Porina sp. 674
6. Ascospores 60-75 × 10-13(-15) µm, 8-celled, ends pointed,
± evenly tapered at both ends; ascomatal warts rather large,
ca. 0.6 mm diam.; Collier, Dade, Putnam and Seminole
counties ................................................................................................................Porina sp. 6
5. Ascospores small, 25-33 × 5-6 µm, 8-celled; ascomatal warts small,
ca. 0.3 mm diam.; Collier County ....................................................................Porina sp. 30308
4. Ascospores clavate with long tapering tail, (9-)11-13-septate,
85-110 × 12-14 µm; common, Texas to North Carolina south to
Seminole County in Florida .................................................... P. heterospora (Fink) R. C. Harris
3. Growing on HCl- rock; thallus relatively smooth; asci ca. 130 × 20 µm;
ascospores 8-celled, fusiform, 43-49 × 8-9 µm; Hillsborough County................................................
.....................................................................................................................Porina sp. Buck 22669
2. Ascospores fusiform, muriform, 9-13-septate with few to most cells longitudinally
or obliquely 1-2-septate, 55-80 × 13-18 µm, usually with well developed gel sheath;
Dade and Lee? counties .......................................................P. nuculastrum (Müll. Arg.) R. C. Harris
1. Thallus and/or ascomatal warts isidiate; ascospores 8-celled, 25-47(-57) × 6.5-8 µm;
North Florida, Louisiana and South Carolina ...................................................... P. scabrida R. C. Harris
NOTES
Porina heterospora (Fink) R. C. Harris
McCarthy (1993) placed this taxon as a synonym of Porina guaranitica Malme. Although I am generally
rather broad minded at the species level, I cannot bring myself to accept this disposition. I have examined the
lectotype of P. guaranitica. It is on rock with a very smooth pinkish thallus. Porina heterospora occurs on bark
and has a verrucose, usually tan thallus. One might be able to dismiss the difference as a consequence of the
semiaquatic habitat of P. guarantica and I would probably be willing to do so if the ascospore size ranges were
more congruent. Based on ten ascospores from the lectotype of P. guaranitica the mean ascospore length is
65.1 µm (range 57-71 µm) with a mean number of 9.5 septa. A small sample of P. heterospora gives 87.3 µm
(range 60-112 µm) and 11.1 septa. McCarthy gave a mean ascospore size of 71.5 µm, presumably based on
a mixture of P. guaranitica and P. heterospora but still well under that of North American collections. The form
of the ascospores is different also. Both are clavate but P. heterospora has a longer tail, seemingly
accounting for the greater ascospore length. Therefore, on the basis of larger, more sepate, longer tailed
ascospores, thallus characters and corticolous substrate, I am maintaining P. heterospora as a distinct
species. This would seem to be the most common species of Porina in the southern Coastal Plain. NY holds
specimens of typical P. heterospora from Cuba and Venezuela but none seen as yet from Brazil. Since the
epithet heterospora has a history of usage both in North America and Great Britain, even if it were a synonym,
I suspect it would be conserved.
Porina nucula Ach.
McCarthy (1993) cited H-Ach 731 as the holotype of this name. However, this consists of two nonidentical
pieces. H-Ach 731-A should be considered the lectotype. H-Ach 731-B is Porina mastoidea s. lat. A
narrow species concept is used here, including only those collections with rather broad, rather short
ascospores with rather blunt ends. Obviously the break between this circumscription and other putative taxa
is not as tidy as one might like. However, I prefer to cut too finely rather than lose information in too broad a
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