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Female big free-tailed bats Nyctinomops macrotis have been captured over water in northern Arizona in high elevation (> 2,400 m) forests and low elevation (1,500 m) desert scrub vegetation. We hypothesized that roost sites were in vertical walls of cliffs that were up to 25 km away from capture sites given the flight capability of these bats. During summer 2005 we captured eight females over ponds and attached radio transmitters to locate day roosts. We also identified locations used during nightly movements from 1 to 6 nights of radio tracking. We found three day roosts for seven bats; average distance (± SE) from a capture site to a roost was 12.1 ± 3.0 km. Roosts were small maternity colonies used by ≥ four N. macrotis in cracks or crevices in upper portions of vertical cliffs and faced south or southeast. Average dimensions for ponds where we found N. macrotis were 24 × 46 m, larger than the average pond size (14 × 19 m) where we did not capture this species. We identified 73 night locations for five N. macrotis and for one individual with 32 night locations calculated a 95% activity area (minimum convex polygon method) of 29,590 ha. Straight line distance between successive locations averaged 5.1 ± 0.8 km. Maximum distance detected from roost averaged 25.3 ± 4.9 km. We conservatively estimated a maximum flight speed of 61 km per hour. Most locations were in desert scrub vegetation but three bats moved to higher elevations, using pinyon-juniper (Pinus edulis-Juniperus spp.) woodland and ponderosa pine (Pinus ponderosa) forest. The maternity roosts we located for N. macrotis were remote, difficult to access, and within protected areas (national parks) in northern Arizona; however, foraging areas and ponds used for drinking are managed by different public or private agencies. These features are not as well protected and could be critically important in this arid environment.
The fossil turtle Kayentachelys aprix is known from Early Jurassic sediments of the Kayenta Formation, Arizona, USA. The detailed description of this taxon’s cranium offered in this paper demonstrates that this turtle presents a mixture of primitive and derived character states. Among others, the presence of an interpterygoid vacuity, a basipterygoid process, a prootic that is exposed in ventral view, and a foramen posterius canalis carotici interni that is formed entirely by the basisphenoid are generally considered primitive for turtles. On the other hand, the presence of an undivided apertura narium, a well developed cavum tympani, an incipient cavum postoticum, and an unpaired vomer are considered to be derived. Kayentachelys aprix has previously been hypothesized to be the oldest stem cryptodiran turtle because of the presence of a flat, vertical plate on the processus pterygoideus externus, and the presence of a processus trochlearis oticum. However, the presence of these characters cannot be confirmed in the available specimens. Other putative stemcryptodiran characters, such as the prefrontal−vomer contact and the presence of an epipterygoid, are herein corroborated as being symplesiomorphies, because they generally appear to be present in basal turtles.
Subgenus Caverneleodes of the genus Eleodes is diagnosed and revised. Six new species from the United States: California (E. microps); Utah and Northern Arizona (E. wynnei), Central Arizona (E. wheeleri), Southern New Mexico (E. guadalupensis), and Mexico (E. thomasi and E. grutus) are described. The biogeography of the subgenus is discussed. Diagnoses and a key are provided to known species of Caverneleodes. Relationships with other Eleodes are discussed. Cave associated Amphidorini are surveyed.
Three genera of xenacanths, based on isolated teeth, occur in the lepospondyl (amphibian)−dominated fauna from the upper Black Prince Limestone (late Bashkirian). Orthacanthus donnelljohnsi sp. nov. teeth, with carinae lacking serrations on the compressed principal cusps, and only one intermediate cusp, represent both adult and juvenile teeth. Heterodonty occurs in both adult and juvenile dentitions. The absence of serrations is unique among Pennsylvanian species of Orthacanthus. Teeth with often highly asymmetrical bases with an aborally−flexed lingual marginal flange (= anterolingual shelf) and a single intermediate cusp are assigned to Triodus elpia sp. nov. A central foramen occurs in the base, unlike most other species; the moderately compressed principal cusps bear generally straight cristae. They represent the first reported occurrence of Triodus in the Paleozoic of North America. Five teeth, with cristae extending from the cusps onto their bases, belong to Bransonella. Two are questionably assigned to Bransonella nebraskensis, one to B. ?lingulata with its labio−lingually elongated apical button and smaller than normal intermediate cusp, and one each to Bransonella sp. “A” and “B”. Bransonella sp. “A” has a base wider (labio−lingual) than long, the reverse of the other Bransonella teeth. Bransonella sp. “B” is distinctly different, as it lacks an intermediate cusp (as in some B. lingulata teeth), and the basal tubercle is beneath one of the cusps (with no evidence of deformity).
The holotype of the brachyopoid temnospondyl Hadrokkosaurus bradyi, represented by a right lower jaw ramus, is re−examined based upon new data and revision of various morphological features. Additional fragmentary jaw material referred to this species is briefly described. Prominent features are a large postsymphyseal foramen that is anteriorly open, and prearticular and surangular buttresses for support of the articular. Brachyopoid characters include a long and robust postglenoid area formed by surangular and prearticular, anterior and posterior keels on at least some marginal dentary teeth, and subtriangular outline of the adductor fossa in dorsal view. Five features of the holotype ramus, long thought to be at odds with its brachyopoid or temnospondyl nature, are critically re−evaluated. A phylogenetic analysis of lower jaw characters in temnospondyls retrieves most of the clades found in more comprehensive data sets, but the statistical node support is low. Brachyopoids are monophyletic, with Hadrokkosaurus emerging as their most basal taxon.
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