Falco powelli sp, nov, (1 Viewer)

[Fred Ruhe]

teven D. Emslie,& Jim I. Mead, 2023

Two New Late Quaternary Avifaunas from the East-Central Great Basin with the Description of a New Species of Falco

Western North American Naturalist. 83 (1): 33–50.
oi:10.3398/064.083.0104

Abstract

We report 2 new late Quaternary avifaunas from cave deposits in Snake Valley, White Pine County, eastern Nevada, that provide new records of extinct and extant species in the east-central Great Basin. These avifaunas collectively represent at least 24 species, including the most northern inland record of California Condor (Gymnogyps californianus) in western North America and a new species of kestrel (Falco sp.) described herein. Two extralimital living species also were identified—the Harlequin Duck (Histrionicus histrionicus) and Snowy Owl (Bubo scandiacus)—and are the first fossil records of these species in the Great Basin. We report the first radiocarbon dates on these 2 species as well as 4 new dates on Greater Sage-Grouse (Centrocercus urophasianus) and 1 on California Condor. The avifauna from these 2 sites, along with 2 other previously published late Pleistocene avifaunas from Smith Creek and Crystal Ball Cave in Snake Valley, comprise a remarkable diversity of extant, extralimital, and extinct species, especially waterfowl, shorebirds, raptors, and vultures that currently occupy a variety of communities, including coniferous forest and woodland, riparian, open sagebrush-steppe, and wetlands and lakes. This avian diversity was facilitated by climatic transitions that occurred before, during, and after the Last Glacial Maximum, when coniferous forest and woodland extended downward in elevation to areas where these caves are located. In addition, a southern arm of Lake Bonneville extended into Snake Valley, with associated wetlands and a high-stand lakeshore that existed only 3–4 km from the mouth of Smith Creek Canyon. The location of these caves placed them in an ecotone adjoining these various mixed communities; their fossil deposits add considerably to our knowledge of late Pleistocene avian communities in the eastern Great Basin.

The authors decribe Faloco powelli

Hope to find the paper so I can give more details.

Fred

 

[Melanie]

Hope to find the paper so I can give more details.

Fred

You've got mail.

 

[Fred Ruhe]

SYSTEMATIC PALEONTOLOGY

Class Aves
Order Falconiformes
Family Falconidae

A complete left tarsometatarsus of a small falcon (Falco sp.) recovered from Level 6 and similar to the American Kestrel (Falco sparverius) in size, is recognized to the genus Falco by its long hypotarsal ridge extending approximately half the length of the shaft (Becker 1987, Suárez and Olson 2001). It is similar to Falco sparverius, but has slightly greater length and other distinct characters described below. Given these differences, this specimen is recognized as a new fossil species of kestrel.

Falco powelli new species

HOLOTYPE.—Complete left tarsometatarsus.

CHRONOLOGY.—Radiocarbon dates from Com bustion Cave range from modern to >52,800 BP (Table 1), with lack of a stratigraphic chronology indicating mixing of cave sediments, likely from rodent activities. The fossil tarsometatarsus, upon recovery, had a thin layer of calcium carbonate over part of the shaft and proximal end, suggesting an older age for this specimen, and it is assumed to be late Pleistocene in age (Holocene fossils exhibit little or no calcium carbonate coating).

ETYMOLOGY.—Named for John D. Powell, U.S. Forest Service, in recognition of his lifelong commitment to the preservation, protection, and conservation of cave resources.

DIAGNOSIS.—Shaft relatively long and slender (the shaft is shorter in Falco sparverius; length of the fossil approaches that of Falco columbarius, but the ends and shaft are distinctly broader and more robust in this latter species). Proximal end with relatively more robust tubercle for tibialis anticus that projects more from the shaft in the fossil species (tubercle less robust and not as prominent in Falco sparverius and Falco columbarius); distal trochleae relatively large and more robust (smaller and less robust in Falco sparverius and Falco columbarius); middle (third) trochlea extends slightly farther up shaft in both anterior and posterior views, with proximal edges more sharply outlined and raised above the shaft than in Falco sparverius and FFalco columbarius.

TYPE LOCALITY.—Combustion Cave, Snake Valley, White Pine County, eastern NevadaNevasa, United States

Fred

P. S.

For all the other species describef in this paper see the paper.


Fig. 1. Holotype tarsometatarsus of Falco powelli new species (left bone in each of the 2 pairs) compared to a large female Falco sparverius (right; UF 24010, formerly 20070) in anterior (left) and posterior (right) views.