A New Hedyotis from Kauai, Hawaiian Islands 
Benjamin C Stone and Irwin Lane 1 
The most recent revision of the Hawaiian 
species of Hedyotis (Rubiaceae) is that of F. R. 
Fosberg (1943), who treated all the Polyne- 
sian species, describing many new forms. The 
genus as considered by Fosberg includes, with 
good reason, the segregate genera Oldenlandia 
L., Gerontogea Cham, and Schlecht., Kadua 
Cham, and Schlecht., Diplophragma Meisn., 
as well as Gouldia romanzoffiensis A. Gray, a 
species not properly in Gouldia . 
The type species of Hedyotis is H. auricularia 
L., which forms also the basis of the subgenus 
Hedyotis. This subgenus contains the species 
native to southern Asia which have axillary 
inflorescences, indehiscent or septicidal fruits, 
and usually a depressed habit of spermacoc- 
coid appearance. The sections and subgenera 
found in Polynesia are as follows. 
Subgenera: Oldenlandia , including only 
Hedyotis biflora L., a wide-spread plant of tropi- 
cal Asia, the islands of the Indian Ocean, 
Malaysia, Micronesia, Melanesia, Fiji, and, 
in Polynesia, Samoa and Tonga. 
Diplophragma , of southern and western Pol- 
ynesia, eastern Melanesia, and Micronesia, 
but not known from Hawaii. 
Kadua , two variable species confined to the 
Hawaiian Islands. 
Oceanica , comprising the single species 
transferred from Gouldia , and present only in 
southern and central Polynesia. 
1 Botany Department, University of Hawaii. Man- 
uscript received March 4, 1957. 
Polynesiotis , with 19 species, principally de- 
veloped in Hawaii, with a secondary center 
in southern Polynesia. This subgenus has five 
sections : Wiegmannia , Protokadua , Gouldiopsis , 
Bikkiocarpa , and Austro gouldia. 
The new species described herein fits well 
into the subgenus Polynesiotis and into the 
section Wiegmannia. However, it differs in 
two of the key characters employed in Fos- 
berg’s key to the subgenera. First, in our 
specimens the stigmas are consistently quadri- 
fid, not bifid; second, the width of the corolla 
tube is not "much less than Vs the length" of 
the corolla tube, as the key states, but is in 
some cases as wide as it is long. At first 
glance the inflorescences seem axillary, but 
on closer inspection it can be seen that they 
are strictly terminal; however, the first axillary 
bud below the inflorescence grows into a 
stem (or in some cases both of the two axil- 
lary buds), and these in turn eventually ter- 
minate in inflorescences; this gives the plants 
an aspect of branching which might be termed 
subscorpioid. 
Within the section Wiegmannia of the sub- 
genus Polynesiotis , our specimens are evidently 
very closely related to Hedyotis littoralis (Hbd.) 
Fosberg, a striking and characteristic species 
distinguished by its fleshy leaves, which are 
closely set on a decumbent corky stem, and 
by its habitat on cliffs or rocks close to the 
sea. It is known mostly from Molokai and 
Maui; although there exist specimens from 
Kauai, Oahu, and Hawaii, they are old (Hille- 
brand’s from Kauai and Oahu, Abbe Faurie’s 
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