Subtribes Goodyerinae and Cranichidinae - The Pollination Biology of North American Orchids: North of Florida and Mexico - page 15

or apomictic. Sun and Wong ( 2001 ) found that populations near Hong Kong are
apomictic and occur only as colonizers of recently disturbed habitats. Adventitious
embryony was, in fact, documented earlier for Z. sulcata 2OXB,INDLEX7IGHT
(Sesshagiriah 1941 ; Swamy 1946 ), now recognized as synonymous with Z. strateu-
matica (World Checklist of Monocotyledons 2008 ) . Such a breeding system would
be consistent with reported low levels of genetic variation within populations and
high levels of population differentiation (Sun and Wong 2001 ). Of five identified
cytotypes all but the 2 n = 20 cytotype have abnormal meiosis (Vij and Vohra 1974 ;
Ackerman 2002a ).
Platythelys Garay
Platythelys is a genus of about 10 species found in the southern United States,
-EXICO#ENTRALAND3OUTH!MERICAANDTHE#ARIBBEAN0RIDGEONETAL 2003 ).
A single species, P. querceticola (Lindl.) Garay (low erythrodes, jug orchid)
( Erythrodes querceticola (Lindley) Ames), occurs in Florida and Louisiana. No
information is available on its pollination, but the presence of a rostellum, viscid-
ium, and saccate nectar spur (Ackerman 2002b ) implies insect vectors.
Cranichidinae
The Cranichidinae include about 17 genera largely restricted to South and Central
!MERICA-EXICOANDTHE#ARIBBEAN0RIDGEONETAL 2003 ). A single genus is pres-
ent in our flora.
Ponthieva R. Brown
Ponthieva is a genus of about 30 widely distributed, tropical and subtropical, Western
Hemisphere species (Pridgeon et al. 2003 ). One, Ponthieva racemosa (Walter)
C. Mohr (shadow witch), is present in our flora. It has a nonresupinate flower
(Fig. 1.4b ) and occurs in the Atlantic and Gulf Coast states from Virginia to east
4EXAS,UER 1972 ; Ackerman 2002c ). Information is limited, but Ackerman ( 1975 )
found Florida populations to be self-compatible and not autogamous. He reported
natural fruit set in 35% of the flowers at one site in northern Florida. Luer ( 1972 )
observed very small halictid bees visiting the flowers in central Florida, but Dressler
( 1993 ) reported that the lip secretes oil, not nectar, and suggested the pollinators
might be anthophorid bees that collect the oil to feed to their larvae.