.--
In a study of a collection of Upper Pleistocene bird fossiis from the Itchtucknee
River, Columbia County, Florida, McCoy (1963, Auk 80:335) described and
named a new genus and species of heron, Palaeophoyx columbiana. This was based
on a nearly complete type coracoid, a less complete paratype coracoid, and a
referred complete left ulna (the type is from the left side and the paratype from
the right--not vice versa as stated by McCoy in the description and the figure
caption). The genus was said to be "referable to the subfamily Ardeinae due to
greater rounding and internal projection of the internal surface of the coraco-
humeral area than found in the Botaurinae" (p. 337). The alleged differences in the
coraco-humeral areas of the two subfamilies are not apparent to me, and the type
and paratype of Palaeophoyx exhibit several distinctive features that are charac-
teristic of Botaurus.
The long and quite slender shaft of the coracoid separates Palaeophoyx from all
the Ardeinae except the night herons (Nycticorax and Nyctanassa), to which
McCoy felt Palaeophoyx most similar. This slenderness is characteristic also of
Botaurus. In the following characters, the type and paratype of Palaeophoyx differ
from the Ardeinae, including the night herons, and agree exactly with Botaurus:
the distinctive bulging of the shaft below the head, the presence of a groove
along the ventral external edge of the shaft immediately above the sterno-coracoidal
process, the lip of the sternal facet placed higher on the shaft and extending only
a little over halfway across the distal expansion. All of these characters are well
shown in McCoy's illustration of the type of Palaeophoyx (p. 338).
The referred ulna was said to differ from modern herons "because of the
external cotyla being more narrow and projected" (p. 339). It differs in several
other respects as well, and I found on comparison that this specimen is from
a Barn Owl, Tyro alba, a species not reported by McCoy from the Itchtucknee.
The error is not quite as egregious as at first might seem. Several skeletal elements
TABLE 1
CORACOID MEASUREMENTS OF "PALAEOPHOYX COLUMBIANA ' COMPARED
TO NEW WORLD BITTERNS
Anterior margin of
Head to glenold facet to
internal distal angle internal distal angle
(mm) (mm)
"Palaeophoyx columbiana" type 47.0 44.9
"Palaeophoyx colurnbiana" paratype -- 46.2
Botaurus lentiginosus (n ----- 27) 47.7-59.6 (54.3) 45.4-56.6 (51.9)
Botaurus pinnatus (n 1) 52.8 50.4
show a superficial resemblance between herons and owls; these are: the humerus,
ulna, distal coracoid, proximal tibia, and femur. The two groups are easily separable
on comparison, and it is unlikely that these superficial similarities are indicative of
any relationship. Nevertheless, it is a pitfall that the avian paleontologist should
be aware of.
The genus Palaeophoyx is clearly untenable and must now be considered
synonymous with Botaurus. Apart from size, I could find no characters to
separate columbianus from Botaurus lentiginosus. Size variation is considerable
in B. lentiginosus (Table 1) but the type of columbianus is smaller (by less than
a millimeter, however) than the smallest of 27 specimens of B. lentiginosus and
one of B. pinnatus examined. B. stellaris of the Old World is a larger species than
lentlginosus. The paratype of columbianus falls within the lower ranges of lenti-
ginosus, only 3 of the 27 specimens of the latter being smaller. It would seem that
B. lentlginosus may have been smaller during the Pleistocene than its modern
representative. Unless further analysis of fossil material should indicate otherwise,
columbianus may be regarded as a somewhat smaller temporal form of Botaurus
lentiginosus.
I am deeply grateful to Pierce Brodkorb for allowing me to examine the speci-
mens of "Palaeophoyx" in his collections and for providing the facilities to study
them.--SToRRs L. OLSON, National Museum of Natural History, Smithsonlan Institu-
tion, Washington, D.C. 20560. Accepted 30 Apr. 73.