Desmodus stocki (Stock's Vampire Bat)

[sordes]

Desmodus stocki

This little known "giant" vampire bat is not only known from pleistocene but also holocene fossils. There are fossils from the San Miguel Island off southern California (Ray et al. 1988), which are only 3000 years old.

Some further information at Darren Naish´s Tetrapod Zoology: scienceblogs.com/tetrapodzoology/2007/02/camazotz_and_the_age_of_vampir_1.php

[another specialist]

Type Specimen: Natural History Museum of Los Angeles County, former California Institute of Technology Museum of Paleontology collection, LACM (CIT) 3129, cranium lacking post-incisor dentition on the left side, zygomatic arches and auditory bullae.

Type Locality and Horizon: Cueva de San Josecito, near Aramberri, Nuevo León state, México; late Pleistocene (late Rancholabrean); cave deposits.

Diagnosis (from Jones 1958): Resembling the Recent Desmodus rotundus but differing from it as follows: Skull larger, heavier and more massive; rostrum and braincase relatively as well as actually broader, interorbital region relatively more constricted; braincase more rounded (less elongate) as viewed from above; nasals less concave in lateral view; narial vacuity broader in relation to greatest length of skull, more nearly heart-shaped; palate broad, less concave medially; mesopterygoid fossa relatively and actually broader anteriorly, the sides nearly parallel; zygomatic arches less rounded in outline, appearing broader owing to the more constricted interorbital region.
Dentition larger and heavier than that in D. rotundus, but otherwise differing only slightly from it; upper incisor less concave on cutting surface; premolar and molar slightly less bladelike, with heavier roots.
The peculiar shape of the incisor of D. stocki is shared to some extent with Diaemus youngi, a Recent South American vampire. However, D. stocki does not otherwise resemble D. youngi, differing from it as follows: Skull larger and heavier; interorbital constriction much narrower; zygomatic arches less strongly bowed; skull less compact, more elongate; braincase and rostrum relatively much narrower in relation to greatest length of skull. Furthermore, specimens of D. stocki show no trace of the minute M2 attributed to D. youngi.

Remarks: Includes Desmodus magnus Gut 1959 as a junior synonym (Hutchison 1967; Morgan 1991).

Other records (summarized in Morgan 1991; and Arroyo-Cabrales and Ray 1997):

Pleistocene (Irvingtonian or Rancholabrean):
Haile 1A local fauna, NE of Newberry, Alachua County, Florida, USA.

Late Pleistocene (Rancholabrean):
Cueva de La Boca, E of Santiago, Nuevo León, México (Arroyo-Cabrales and Ray 1997).

Cueva La Presita, near Matehuala, San Luis Potosí, México (Arroyo-Cabrales and Ray 1997).

Grutas de Loltún, Yucatán, México (Arroyo-Cabrales and Alvarez 1990).

Haile 11B local fauna, NE of Newberry, Alachua County, Florida, USA.

Arredondo 2A local fauna, SW of Gainesville, Alachua County, Florida, USA.

Reddick 1 fauna, Marion County, Florida (as Desmodus magnus, a junior synonym of D. stocki; Gut 1959).

Potter Creek Cave, Shasta County, California, USA (Hutchison 1967).

Rampart Cave, Mohave County, Arizona, USA.

Arkenstone Cave, Pima County, Arizona, USA (Czaplewski and Peachey in press).

U-Bar Cave, Hidalgo County, New Mexico, USA.

Little Thirty-eight Mine, Brewster County, Texas, USA.

New Trout Cave, Pendleton County, West Virginia, USA (Grady et al. 2002).

Holocene:

www.snomnh.ou.edu/collections-res....tml#Anchor-7431

[another specialist]

Stock's vampire D. stocki Jones, 1958 was the most northerly-occurring vampire, and occurred in California and West Virginia as well as Mexico and elsewhere. In being about 15-20% bigger than the Common vampire, it introduces us to the interesting fact that a few extinct vampires were rather bigger than the living species. A species named from Florida, D. magnus Gut, 1959, is regarded nowadays as a synonym of D. stocki. Jones' 1958 paper on D. stocki was submitted for publication 11 days prior to Gut's 1959 paper on D. magnus, and while D. stocki was first named for crania, D. magnus was first named for lower jaws. While writing their descriptive papers, both authors were unaware of the other's work, and subsequent study has shown the bats they named to be the same species. D. stocki had relatively larger and broader cheek teeth than the Common vampire, its upper incisors were different in shape, and its hindlimbs were shorter and more robust. The adjacent image is a D. stocki humerus [borrowed from here].



scienceblogs.com/tetrapodzoology/2007/02/giant_extinct_vampire_bats_ban.php

[another specialist]

Desmodus stocki
Type Specimen: Natural History Museum of Los Angeles County, former California Institute of Technology Museum of Paleontology collection, LACM (CIT) 3129, cranium lacking post-incisor dentition on the left side, zygomatic arches and auditory bullae.

Type Locality and Horizon: Cueva de San Josecito, near Aramberri, Nuevo León state, México; late Pleistocene (late Rancholabrean); cave deposits.

Diagnosis (from Jones 1958): Resembling the Recent Desmodus rotundus but differing from it as follows: Skull larger, heavier and more massive; rostrum and braincase relatively as well as actually broader, interorbital region relatively more constricted; braincase more rounded (less elongate) as viewed from above; nasals less concave in lateral view; narial vacuity broader in relation to greatest length of skull, more nearly heart-shaped; palate broad, less concave medially; mesopterygoid fossa relatively and actually broader anteriorly, the sides nearly parallel; zygomatic arches less rounded in outline, appearing broader owing to the more constricted interorbital region.
Dentition larger and heavier than that in D. rotundus, but otherwise differing only slightly from it; upper incisor less concave on cutting surface; premolar and molar slightly less bladelike, with heavier roots.
The peculiar shape of the incisor of D. stocki is shared to some extent with Diaemus youngi, a Recent South American vampire. However, D. stocki does not otherwise resemble D. youngi, differing from it as follows: Skull larger and heavier; interorbital constriction much narrower; zygomatic arches less strongly bowed; skull less compact, more elongate; braincase and rostrum relatively much narrower in relation to greatest length of skull. Furthermore, specimens of D. stocki show no trace of the minute M2 attributed to D. youngi.

Remarks: Includes Desmodus magnus Gut 1959 as a junior synonym (Hutchison 1967; Morgan 1991).

Other records (summarized in Morgan 1991; and Arroyo-Cabrales and Ray 1997):

Pleistocene (Irvingtonian or Rancholabrean):
Haile 1A local fauna, NE of Newberry, Alachua County, Florida, USA.

Late Pleistocene (Rancholabrean):
Cueva de La Boca, E of Santiago, Nuevo León, México (Arroyo-Cabrales and Ray 1997).

Cueva La Presita, near Matehuala, San Luis Potosí, México (Arroyo-Cabrales and Ray 1997).

Grutas de Loltún, Yucatán, México (Arroyo-Cabrales and Alvarez 1990).

Haile 11B local fauna, NE of Newberry, Alachua County, Florida, USA.

Arredondo 2A local fauna, SW of Gainesville, Alachua County, Florida, USA.

Reddick 1 fauna, Marion County, Florida (as Desmodus magnus, a junior synonym of D. stocki; Gut 1959).

Potter Creek Cave, Shasta County, California, USA (Hutchison 1967).

Rampart Cave, Mohave County, Arizona, USA.

Arkenstone Cave, Pima County, Arizona, USA (Czaplewski and Peachey in press).

U-Bar Cave, Hidalgo County, New Mexico, USA.

Little Thirty-eight Mine, Brewster County, Texas, USA.

New Trout Cave, Pendleton County, West Virginia, USA (Grady et al. 2002).

Holocene:
Cerro de Tlapacoya, SE of la Ciudad de Mexico, México (Alvarez 1972; Arroyo-Cabrales and Ray 1997).

San Miguel Island, Santa Barbara County, California, USA (Guthrie 1980).

www.snomnh.ou.edu/collections-research/cr-sub/vertpaleo/fossil_bats/IT_phyllostomidae.html

[Melanie]

Desmodus stocki Jones, 1958
Referred Specimens

right I1 fragment (OMNH 70522); left I1 (58565; Fig. 2); left C1 (58622; Fig. 2); periotic (57192; Fig. 1); basioccipital fragment and other small braincase fragments (57416); clavicle (58623); 4 fragments of humerus (58566); 4 shaft fragments of radius (57369); metacarpal fragment (58653); left astragalus (57368); phalanges (58567, 70523); ungual phalanx (57417).
Comments

The upper incisors are greatly enlarged, flattened, and bladelike. The left I1 from Arkenstone Cave measures 3.3 mm in anteroposterior length (along the approximate alveolar edge), 6.7 mm in overall length (actual dimension from root apex to crown apex, not accounting for slight breakage at both ends), and 1.0 mm in transverse width. Crown height of I1 above the alveolus cannot be measured directly because the tooth is not in situ in the premaxilla and its tip is broken, but this measurement was estimated at 3.7 mm.

Although the tip of the left upper incisor is slightly damaged and the right one is more heavily damaged, the shape of these unique teeth is diagnostic of vampires, Desmodontinae (Fig. 2). No other mammals possess incisors of this shape. Known vampires include the extant species Desmodus rotundus, Diphylla ecaudata, and Diaemus youngi, and the extinct species Desmodus archaeodaptes, Desmodus stocki, and Desmodus draculae. Desmodus rotundus is also known as a fossil in the late Pleistocene in Mexico, Cuba, and South America, and Diphylla ecaudata is also known near the Pleistocene-Holocene boundary in Mexico and in the late Pleistocene in South America. Desmodus archaeodaptes is known only from the late Pliocene of Florida. Desmodus stocki occurs in the late Pleistocene to middle Holocene of Mexico and the United States. Fossils of Desmodus draculae are found in the late Pleistocene to late Holocene of Central America (including the Yucatan Peninsula of Mexico) and South America.

The Arkenstone Cave incisors are much larger than those of D. archaeodaptes, D. rotundus, D. ecaudata, and D. youngi, and are slightly smaller than in D. draculae of Central and South America (Arroyo-Cabrales and Ray, 1997; Czaplewski and Cartelle, 1998). Their dimensions match those in the extinct North American Quaternary species D. stocki. Desmodus stocki and D. draculae are separable based on shape characteristics of the skull (Morgan et al., 1988), but the critical parts of the cranium are not preserved in the Arkenstone Cave fragments.

Another distinctive element is the upper canine (58622). The crowns of the upper canines of vampires, like the first upper incisors, are flattened and bladelike. The isolated tooth from Arkenstone Cave has an expanded root with a strong twist about its longitudinal axis. It is 6.15 mm in overall length (from root apex to crown apex). The anteroposterior length at the level of the alveolus is 2.6 mm, transverse width is 0.9 mm, and crown height above the estimated level of the alveolus is 3.1 mm. Like the upper incisor, these canine measurements fall between those of modern specimens of D. rotundus and of D. draculae (Pardiñas and Tonni, 2000; pers. obser.).

Only a few poorly preserved scraps represent the radius of this bat; a 1-cm-long fragment of the shaft has a greatest diameter of 2.5 mm. The astragalus is larger than that in a modern specimen of Desmodus rotundus but matches its morphology; fossil astragali of D. stocki were not available for comparison. Other than the upper incisor and canine, the periotic bone (Fig. 1) is the most distinctive element in the available sample of specimens. Its size and morphology, as well as those of the fragments of radius and basioccipital, match the same elements of D. stocki to which they were compared. In attempting to identify the periotic and compare its size with periotics of other fossil vampires, we measured known specimens from other localities. We also compared the shape of the periotic (where disarticulated or dissected comparative specimens were available, or periotics still attached to crania were not obscured by the auditory bullae) to that of other genera of Phyllostomidae and to representative genera of the Emballonuridae, Mormoopidae, Noctilionidae, Natalidae, Thyropteridae, Molossidae, and Vespertilionidae. The periotic of the Arkenstone Cave specimen differs in morphology from periotics of these other families and also from other large Neotropical phyllostomids. It is similar in shape, size, and in the dimensions of its various minute openings to several periotics of D. stocki from New Trout Cave, West Virginia (Grady et al., 2002), and Reddick, Florida (Morgan, 1991) (Table 1). A single periotic of the large D. draculae was available for comparison; it is barely larger in most measurements than periotics of D. stocki, including the Arkenstone Cave specimen.

Among the Arkenstone Cave vampire bones there are no redundant skeletal elements and no indication that more than 1 bat is represented in the deposit. No elements of any other large species of bat are present among the thousands of bones recovered from the small deposit. We conclude that the separate elements belong to a single species and probably a single vampire bat.

Aside from the relatively subtle morphological differences among the late Quaternary vampires D. draculae, D. stocki, and D. rotundus (Morgan et al., 1988), the size differences in certain dimensions of some skeletal and dental elements among these species might overlap if larger samples of better preserved fossils were available (Morgan et al., 1988; Arroyo-Cabrales and Ray, 1997). In the future, better samples of D. stocki and D. draculae, as well as Pleistocene fossils of D. rotundus, might eventually show clinal variation or indicate that these named species are temporal or geographic variants of a single lineage. Such a possibility has been mentioned by previous authors (Morgan et al., 1988; Arroyo-Cabrales and Ray, 1997), but its determination is beyond the conclusions that can be supported by currently available specimens of the 3 species, and also beyond the scope of this paper. In the meantime, available dimensions of the scraps from Arkenstone Cave match the size criteria currently associated with D. stocki and are smaller than those associated with D. draculae. We therefore refer the Arkenstone specimens to D. stocki.

The vampire D. stocki is known from several late Pleistocene localities in southern North America (Ray et al., 1988; Arroyo-Cabrales and Ray, 1997); its presence in Arkenstone Cave, combined with its known and inferred distribution elsewhere, suggests a late Pleistocene age for the Arkenstone Cave deposit. This represents the first record of D. stocki as a fossil in southern Arizona.

LATE PLEISTOCENE BATS FROM ARKENSTONE CAVE, ARIZONA

www.bioone.org/doi/abs/10.1894/0038-4909%282003%29048%3C0597%3ALPBFAC%3E2.0.CO%3B2?prevSearch=%255BAllField%253A%2Bdesmodus%2Bdraculae%255D&searchHistoryKey=&queryHash=51f263c2024172fdbd7e1a063faf36fe

[Melanie]

The first description of Desmodus stocki is online:

J. Knox Jones, jr.: "Pleistocene Bats from San Josecito Cave, Nuevo Leon, Mexico" In: University of Kansas publications, Museum of Natural History. 1958, p 392-393

www.biodiversitylibrary.org/page/2978496#page/426/mode/1up

[Sebbe]

Desmodus stocki :: Florida Museum of Natural History

www.flmnh.ufl.edu/florida-vertebrate-fossils/species/desmodus-stocki/

[Sebbe]

Flightless ducks, giant mice and pygmy mammoths: Late Quaternary extinctions on California’s Channel Islands

Explanations for the extinction of Late Quaternary megafauna are heavily debated, ranging from
human overkill to climate change, disease and extraterrestrial impacts. Synthesis and analysis of Late
Quaternary animal extinctions on California’s Channel Islands suggest that, despite supporting
Native American populations for some 13,000 years, few mammal, bird or other species are known
to have gone extinct during the prehistoric human era, and most of these coexisted with humans for
several millennia. Our analysis provides insight into the nature and variability of Quaternary
extinctions on islands and a broader context for understanding ancient extinctions in North
America.

courtneyhofman.com/wp-content/uploads/2014/09/Rick-et-al.-2012.pdf

[Sebbe]

Paleoclimatic Reconstruction Based on the Late Pleistocene San Josecito Cave Stratum 720 Fauna Using Fossil Mammals, Reptiles, and Birds.

Advances in technology have equipped paleobiologists with new analytical tools to assess the fossil record. The functional traits of vertebrates have been used to infer paleoenvironmental conditions. In Quaternary deposits, birds are the second-most-studied group after mammals. They are considered a poor paleoambiental proxy because their high vagility and phenotypic plasticity allow them to respond more effectively to climate change. Investigating multiple groups is important, but it is not often attempted. Biogeographical and climatic niche information concerning small mammals, reptiles, and birds have been used to infer the paleoclimatic conditions present during the Late Pleistocene at San Josecito Cave (~28,000 14C years BP), Mexico. Warmer and dryer conditions are inferred with respect to the present. The use of all of the groups of small vertebrates is recommended because they represent an assemblage of species that have gone through a series of environmental filters in the past. Individually, different vertebrate groups provide different paleoclimatic information. Birds are a good proxy for inferring paleoprecipitation but not paleotemperature. Together, reptiles and small mammals are a good proxy for inferring paleoprecipitation and paleotemperature, but reptiles alone are a bad proxy, and mammals alone are a good proxy for inferring paleotemperature and precipitation. The current paleoclimatic results coupled with those of a previous vegetation structure analysis indicate the presence of non-analog paleoenvironmental conditions during the Late Pleistocene in the San Josecito Cave area. This situation would explain the presence of a disharmonious fauna and the extinction of several taxa when these conditions later disappeared and do not reappear again.

www.mdpi.com/1424-2818/15/7/881