NOTES ON THE TAXONOMY OF Calomys laucha (RODENTIA, CRICETIDAE), WITH THE DESIGNATION OF A NEOTYPE.
Calomys laucha (Fischer, 1814) is a small phyllotine rodent (<20 g), widely distributed from northern Paraguay and southeastern Bolivia to southern Brazil, Uruguay and central Argentina (Salazar-Bravo 2015). The species name was coined by Fischer (1814: 71) as Mus Laucha et Lauchita, based on the "rat septieme ou rat laucha" described by the Spanish naturalist Felix de Azara in 1801. The original description was also taken by Olfers (1818: 209), who used it as a reference for his M[us]. laucha. Like other several forms described by Azara, the absence of a type specimen and the uncertainty about the exact location of the collection site have been decisive in the subsequent complex taxonomic history of this species (Tate 1932).
Hershkovitz (1962) revised C. laucha, including as synonyms several nominal forms that today are recognized as valid species (e.g., C. hummenlincki, C. musculinus, C. tener) and restricted its type locality to Asuncion, eastern Paraguay. Massoia et al. (1968) redefined the concept of C. laucha, referring its terra typica to the vicinities of Buenos Aires, Argentina, and removing from under its synonymy the currently accepted C. musculinus (Thomas, 1913). Other nominal taxa, such as C. tener (Winge, 1887) and C. hummelincki (Husson, 1960) have not been studied and compared to the detail that Massoia et al. (1968) employed in comparing C. laucha and C. musculinus. However, phylogenetic analyses of mitochondrial genes, coupled with chromosomal counts, spermatic morphology and skull morphometrics have been useful in assigning specific status to these species (e.g., Olds 1988; Perez-Zapata et al. 1997; Bonvicino & Almeida 2000; Salazar-Bravo et al. 2001). Most of subsequent authors maintained Paraguay as the type locality of C. laucha (e.g., Musser & Carleton 2005; Salazar-Bravo 2015), following the restriction made by Hershkovitz (1962).
In a recent contribution, Gonzalez-Ittig et al. (2014), based on the analyses of cytochrome b (Cyt-b) sequences, recognized two main clades in the current distribution of C. laucha, one encompassing populations in southern Brazil and Uruguay and another including those from the remainder of the distribution in Argentina, Bolivia and Paraguay. However, these authors did not include specimens from the Argentinean Mesopotamia, leaving some doubts about the limits between both clades. Finally, Gonzalez-Ittig et al. (2014) recorded only C. tener in eastern Paraguay, challenging the traditional view of this area as occupied by C. laucha.
With the above described scenario, the present work has two objectives: 1) to provide, based on cytochrome b (Cyt-b) sequences, an update on the genetic composition of eastern and western clades of C. laucha, increasing the sampling made by Gonzalez-Ittig et al. (2014); 2) to stabilize the taxonomy of this widespread sigmodontine, by designating a neotype and assigning a new type locality for the species.
MATERIALS AND METHODS
We expanded and complemented the Cyt-b gene matrix of Gonzalez-Ittig et al. (2014) by incorporating sequences of individuals from new localities in Uruguay and Argentina: Uruguay: Rincon del Colorado (Canelones), Punta Gorda (Colonia), Estancia Loma del Queguay (Paysandu), Estancia Los Paraisos (Artigas) and Valle Platon (Rivera). Argentina: Estacion San Jose (Buenos Aires), Arraga (Santiago del Estero) and Nogoya (Entre Rios). Thus, the present study includes 12 localities from Argentina, 6 from Paraguay, 1 from Bolivia, 6 from Uruguay and 1 from Brazil (Table 1 and Fig. 1).
DNA extractions were performed according to the standard CTAB protocol. The complete Cyt-b was amplified with the primer combination Mus14095/ Mus15398 according to the conditions described in Gonzalez-Ittig et al. (2010). All sequencing reactions were performed by Macrogen USA Inc. (http://www. macrogenusa.com). Nucleotide alignments were produced using MAFFT v7 (Katoh & Standley 2013). We used different iterative refinement methods to detect changes in the Cyt-b alignment; the slow options LINS-i and G-INS-I, with gap opening penalty: 1.53, gap extension penalty: 0.1, were tested. Regardless of the method used, the alignment was always the same, since no gap was detected.
The number of haplotypes was obtained with the program DnaSP v5 (Rozas et al. 2003). We used Network v220.127.116.11 (Bandelt et al. 1999), with the maximum parsimony post-processing analysis, to draw a median-joining network and to analyze the relationships among the haplotypes detected. To compare with other studies, we used the Kimura 2 parameters (K2P) algorithm to estimate the levels of genetic distances and sequence divergence within and between clades.
Nomenclature used to describe the anatomy of the skull follows Carleton & Musser (1989) and Steppan (1995), and that of the molars follows Reig (1977). The measurements provided were taken with a digital caliper and recorded to the nearest 0.01 mm following Hershkovitz (1962) and Musser et al. (1998).
Thirty-three specimens of C. laucha were clustered into 23 haplotypes, which formed two haplogroups (Fig. 2). Haplogroup A included 20 haplotypes corresponding to 24 specimens from Argentina, Bolivia and Paraguay, and haplogroup B included 3 haplotypes corresponding to nine individuals from one locality in the Argentinean Mesopotamia (#12 in Fig. 1), and from all sampled localities of Brazil and Uruguay. A total of 36 substitutions separated the haplogroups (Fig. 2); the mean inter-subclade K2P genetic differentiation was 5.47% (4.74% - 6.53%). None of the haplotypes of subclade A were shared among individuals from different countries; the mean intra-sub-clade A differentiation was 1.11% (0.13% - 2.71%).
The International Code of Zoological Nomenclature (ICZN 1999; see Article 75.3.1) justifies the designation of a neotype under "... the express purpose of clarifying the taxonomic status or the type locality [italics are ours] of a nominal taxon." Based on the premises discussed above, we designate a neotype for Calomys laucha as follows:
Calomys laucha (Fischer, 1814)
Neotype.--MACN-Ma 18795 (original collector's number 7317), adult scrotal male collected by James N. Mills on November 30th, 1988; preserved as skin and skull in good condition (Fig. 3).
Measurements of the neotype in mm (external measurements were taken from the label).--Total length = 140; tail length = 55; hindfoot length (with claw) = 17; ear length = 14; greatest length of skull = 22.21; condylo-incisive length = 20.53; greatest zygomatic breadth = 11.76; least interorbital breadth = 3.40; length of nasals along midline = 9.05; breadth of braincase = 9.45; breadth of the zygomatic plate = 2.37; length of incisive foramina = 5.10; maximum breadth across the incisive foramina = 1.65; length of palatal bridge = 3.55; bullar length less tube = 3.35; alveolar length of the maxillary toothrow = 3.04; alveolar length of the mandibular toothrow = 2.84.
Type locality.--Estacion Experimental Agropecuaria Pergamino (33[degrees]55'S, 60[degrees]35'W; 65 m a.s.l.), Partido de Pergamino, Provincia de Buenos Aires, Argentina.
Distribution.--Natural grasslands, cultivate fields and forest fringes, up to an elevation of 1000 m, from northern Paraguay and southeastern Bolivia to southern Brazil, Uruguay and central Argentina (Salazar-Bravo 2015; see inset on Fig. 1).
Emended diagnosis (modified from Salazar-Bravo 2015).--A member of the tribe Phyllotini, subfamily Sigmodontinae, characterized by the following combination of characters: size small (12-20 g; total length ~125 mm), overall dorsal coloration olive gray, with brown and golden hairs intermingled, darker at the midline and clearly separated from the white of the venter; ears with a white patch of hairs behind; tail bicolored, ~43% of the combined length of the head and body; skull small (GLS ~22 mm), with straight lateral profile, rostrum short and narrow; interorbital region wide, with posterior divergent supraorbital edges; braincase large and rounded; zygomatic plate broad, with free upper border enclosing a poorly developed zygomatic notch; palate long, wide and flat; upper incisors smooth, hyperopisthodont and faced with light orange enamel; molars small (upper molar series <3.3 mm), brachydont, trilophodont and crested; main lingual and labial cusps in alternate pairs; M1 subrectangular in outline; procingulum well developed deeply divided by an anteromedian flexus and with a single anteromedian style typically present; M3 approximately equal to 50% of the M2 and rounded; stomach unilocular-hemiglandular; glans penis complex, with a tridigitate bacular cartilage; gall bladder present; 2n = 64; FN = 68-72.
Remarks.--The morphological distinction between C. laucha and the widely sympatric C. musculinus was explored by Massoia et al. (1968). Synonymy, description, distribution, geographical and karyotypic variation and natural history were synthesized by Salazar-Bravo (2015); stomach morphology was described by Carleton (1973); morphology of male accessory glands was documented by Voss & Linzey (1981). Ecology, diet, reproduction and habitat selection well characterized, especially for the pampean region of Buenos Aires and Cordoba provinces populations (see review in Polop & Busch 2010). The species C. laucha from Argentina and Uruguay has a 2N = 64, FN = 68-72 (Bonvicino et al. 2010). The karyotype with a 2N = 56; FN = 59, reported by Brum-Zorrilla (1962) for one specimen attributed to this species should dismissed as no voucher is available to confirm the identification (EG, pers. obs.).
The current concept of C. laucha includes two main clades, one encompassing sampled populations in southern Brazil, Uruguay and 1 locality in Argentina and another including those from the remainder of the distribution in Argentina, Bolivia and Paraguay. The karyotype of individuals assigned to both of these haplogroups is the same and includes a diploid count of 2N = 64 (Gardenal et al. 1977; Brum-Zorrilla et al. 1990; Mattevi et al. 2005; Badzinski et al. 2012). No metric or detailed qualitative or quantitative morphological studies encompassing populations from throughout the range of this species have been published to date. According to Gonzalez-Ittig et al. (2014), if the two main clades represent distinct, cryptic species, the available names for them would be C. bimaculatus Waterhouse, 1837 (type locality "Maldonado," Maldonado, Uruguay [Waterhouse, 1837: 18]) and C. laucha. However, these authors overlooked the fact that Mus (?) dubius Fischer, 1829, with type locality restricted to "Sao Gabriel (30[degrees]19'S, 54[degrees]19'W, 118 m, Rio Grande do Sul, Brazil" (Pardinas et al. 2007: 401) is also an available name for Uruguayan and Brazilian populations. If dubius proves to be a synonym of bimaculatus, then this name should correspond by priority, at species or subspecies level, to those populations of Brazil and Uruguay. Mus (?) dubius Fischer, 1829 was based on the "blanco debaxo," described also by Azara (1802). Cabrera (1961: 477) used the name dubius as valid and included into its synonymy, at subespecific level, the nominal forms bimaculatus and bonariensis Osgood, 1933 (type locality "Torrecita, province of Buenos Aires, Argentina;" Osgood 1933: 14).
Regarding the type locality of C. laucha, when discussing his "rat septieme ou rat laucha," Azara indicated that his servant Francisco had taken two animals from a "paille de mais d'un Chacarra of Buenos-Ayres, et un autre dans les Pampas, par les vingt-cinq degres de latitude" (freely translated as "from a maize straw at a farm in Buenos Aires, and another from the Pampas, by the twenty-five degrees of latitude"). Olfers (1818: 209) referred the origin of laucha as "Paraguay" and Hershkovitz (1962: 153), following Olfers (1818) and invoking his right as first reviser, restricted the type locality to "neighborhood of Asuncion [sic], Paraguay." Cabrera (1961: 479) instead, referred the type locality of this species to "...las quintas de Buenos Aires." Mistakenly, Hershkovitz (1962: 153) concluded that in the late XVIII century, Buenos Aires included the current areas of Uruguay and the Argentinean provinces of Misiones, Corrientes and Entre Rios, electing to restrict the type locality to the vicinity of Asuncion, Paraguay, in reference to the "vingtcinq ... degres of latitude" from Azara's statement. Part of the ideas of Hershkovitz (1962: 153) were based on the assumption that Azara had not worked in the area of the present province of Buenos Aires, an inference widely refuted by historic documents (e.g., Mones & Klappenbach 1997; Contreras Roque 2010). Clearly, the specimens that Azara (1801) used in his description correspond to animals caught at two different localities, one in the vicinity of Buenos Aires ("paille de mais d'un Chacarra of Buenos-Ayres,..") and another in Paraguay ("... dans les Pampas, par les vingt-cinq degres de latitude"). The restriction made by Hershkovitz (1962) to Paraguay is not convenient; based on our current knowledge, only C. tener is confidently reported in the eastern portion of this country (see Gonzalez-Ittig et al., 2014). Thus, conceivably, Azara's "rat septieme ou rat laucha" could be a composite between these two, externally very similar, taxa. As the designation of a neotype implies a redefinition of the type locality, we chose this action to correct the restriction made by Hershkovitz (1962), restoring part of the original reference of Azara (1801) to northern Buenos Aires, central-eastern Argentina. The choice of a neotype from central Argentina has the additional benefit that populations of northern Buenos Aires province have been pivotal in defining the current concept of C. laucha (e.g., Massoia & Fornes 1965; Massoia et al. 1968). Other sigmodontines and didelphids described by Azara (1801, 1802) have similar taxonomic histories, where the need to avoid confusion has led to the designation of neotypes; among others, Oligoryzomys nigripes (Myers & Carleton 1981), Oxymycterus rufus (Oliveira & Goncalves 2015), Sooretamys angouya (Musser et al. 1998), or Thylamys pusilla (Voss et al. 2009).
The course of action taken above has implications on many fronts, especially for the taxonomy of small-bodied Calomys present in the provinces of Corrientes and Entre Rios, between the Parana and the Uruguay rivers; this region, known as the Argentinean Mesopotamia, covers upwards of 167 000 [km.sup.2]. In the present study we included one specimen from Entre Rios Province, which clustered within the haplogroup B. If this is the only form present in Mesopotamia, then the Parana River might potentially be acting as a geographic barrier separating individuals of these distinct clades. This is an important issue, since both the Parana and Uruguay rivers appear to be barriers for other species' distributions; for example, Scapteromys (in which eastern and western clades are separated by the Uruguay River; see D'Elia & Pardinas 2004) and Reithrodon (in which the clades referred to the species typicus and auritus are apparently separated by the Parana River; see Pardinas et al. 2015). Nevertheless, we sequenced only one individual from Entre Rios, and many other populations of small-sized Calomys are known from this region (e.g., Hershkovitz 1962; Massa et al. 2014). In fact, we cannot exclude the possibility that C. tener could also be present in the northern portion of the Mesopotamia, since C. tener and C. laucha clade B are nearly sympatric at similar latitudes in southern Brazil (Quintela et al. 2014). Calomys tener is present in eastern Paraguay and in the Argentinean province of Misiones (Gonzalez-Ittig et al. 2014), and the southern limit of its distribution, as well as those of C. laucha in this region, are currently unclear. In fact, although we lack Cyt-b confirmation about the presence of C. laucha in eastern Paraguay and northeastern Argentina, the species has been mentioned several times for these territories (see Salazar-Bravo 2015). C. laucha was first mentioned for Misiones province by Massoia (1980, 1983), based on materials derived from owl pellets recovered in the locality of El Cruce, about 7 km NE Aposteles. Later, Massoia (1988) introduced the first reference to C. tener based on animals from Campo Ramon, a forested region near Obera. In his synthesis on the rodents from Misiones, Massoia (1993) stated the presence of both species of Calomys in this province, referring the distribution of C. laucha to the southern unforested portion and restricting C. tener to central forested localities. The occurrence of C. tener in Misiones was summarily dismissed by Pardinas & Teta (2006) and the sylvan populations of Calomys were referred to C. laucha. Clearly, Calomys is an important component of the small mammal assemblages in central and southern Misiones as well as in northeastern Corrientes (Teta & Pardinas 2007) and its alpha-taxonomy in this large territory deserves further inspection. The same is true for the eastern half of Paraguay, an area of fragmented forests intermixed with agricultural lands and open grasslands, in which both species appear as sympatric (cf. Salazar-Bravo 2015).
In summary, additional data are still needed to better address the taxonomy of C. laucha and to delimit with accuracy its geographical distribution, especially in the areas in which C. laucha and C. tener could be sympatric (e.g., northeastern Argentina). Additional qualitative and quantitative morphological approaches are needed, as they could add substantial data, together with molecular markers, to the recognition of eastern and western clades as different entities (i.e., species or subspecies). In addition, the analysis of DNA sequences of more specimens from the Argentinean Mesopotamia is necessary to solve their taxonomic status, and consequently, to add a new piece in the biogeographical puzzle of the mammals of this part of the La Plata River Basin.
Recibido 29 noviembre 2016. Aceptado 27 abril 2017. Editor asociado: E Palma
Sergio Lucero (MACN) helped us at the first stages of this work. James Mills shared with us some field notes about the individual here selected as neotype. We thank Silvana Levis, Gladys Calderon and Maria Laura Martin from INEVH (Pergamino, Argentina) for providing some of the specimens and sequences used in this study. The following institutions supported this study: Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET, PIP 11220150100474C0 to Cristina N. Gardenal), Secretaria de Ciencia y Tecnologia (SECYT) of the Universidad Nacional de Cordoba, and Agencia Nacional de Promocion Cientifica y Tecnologica (PICT 2012-1275 to Cristina N. Gardenal and PICT 2014-1039 to UFJP). JSB acknowledges the support of the American Philosophical Society, a grant from the Systematics Research Fund of the Systematics Association and Faculty Research Award from Texas Tech University.
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Pablo Teta (1), Raul E. Gonzalez-Ittig (2), Enrique M. Gonzalez (3), Ulyses F. J. Pardinas (4), and Jorge Salazar-Bravo (5)
(1) Division Mastozoologia, Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", Buenos Aires, Argentina. [Correspondence: Pablo Teta <email@example.com>]
(2) Instituto de Diversidad y Ecologia Animal (IDEA), CONICET-UNC and Facultad de Ciencias Exactas, Fisicas y Naturales, Universidad Nacional de Cordoba, Cordoba, Argentina.
(3) Museo Nacional de Historia Natural, Montevideo, Uruguay.
(4) Instituto de Diversidad y Evolucion Austral (IDEAus, CONICET), Puerto Madryn, Chubut, Argentina.
(5) Department of Biological Sciences, Texas Tech University, Lubbock, Texas 79409, USA.
Caption: Fig. 1. Map of geographical locations of individuals listed in Table 1. Circles represent localities sampled in the present study; the star corresponds to the type locality of the neotype designated herein for Calomys laucha. The inset depicts the distributional range of C. laucha based on marginal localities (modified from Salazar-Bravo, 2015).
Caption: Fig. 2. Minimum spanning network showing the relationships and relative abundance of the Cyt-b haplotypes of C. laucha. The geographic origin of each haplotype is indicated with a different color or drawing pattern. Each bar through the solid line represents one nucleotide difference between haplotypes.
Caption: Fig. 3. From top to bottom: right lateral, ventral and dorsal views of the skull and labial view of the mandible of the neotype of Calomys laucha (MACN 18795; Argentina, Buenos Aires, Estacion Experimental Agropecuaria Pergamino). Scale = 5 mm.
Table 1 Field identification code or collection numbers of the specimens from which tissues were obtained. Location of the sampling sites is showed in Fig. 1 (in parenthesis, the provinces or departments), geographic coordinates, GenBank accession numbers and Museums or Collections where the voucher specimens are deposited. Voucher Sample location Number Argentina 12942 (1) Pergamino (Buenos Aires) 1874 (2) Chillar (Buenos Aires) 1882 (2) Chillar (Buenos Aires) 1297 (3) Orense (Buenos Aires) 1320 (3) Orense (Buenos Aires) CNP 5053 (4) Estacion San Jose (Buenos Aires) CE21 (5) Capilla de los Remedios (Cordoba) CE29 (5) Capilla de los Remedios (Cordoba) CE32 (5) Capilla de los Remedios (Cordoba) SL2 (6) Donovan (San Luis) SL26 (6) Donovan (San Luis) NK15988 (7) Maximo Paz (Santa Fe) 19328 (8) Uranga (Santa Fe) 21978 (9) Maciel (Santa Fe) B18 (10) Berna (Santa Fe) 37981 (11) Arraga (Santiago del Estero) 38779 (12) Nogoya (Entre Rios) Paraguay TK122109 (13) Rio Verde, Estancia Salazar (Presidente Hayes) NK72376 (14) Filadelfia (Boqueron) TK122274 (15) Fortin Teniente Montania (Boqueron) TK66497 (16) Parque Nacional Teniente Enciso, 4 km NW of administration (Boqueron) TK65638 (17) Destacamento Gabino Mendoza (Alto Paraguay) TK67304 (18) Estancia Kamba Aka (Alto Paraguay) Bolivia NK25158 (19) Estancia Bolivar (Tarija) NK25156 (19) Estancia Bolivar (Tarija) Uruguay MNHN5311 (20) Rincon del Colorado (Canelones) PV52 (21) Puntas de Valdez (San Jose) PV54 (21) Puntas de Valdez (San Jose) MNHN7962 (22) Punta Gorda (Colonia) MNHN7963 (23) Estancia Loma del Queguay (Paysandu) MNHN7156 (24) Estancia Los Paraisos (Artigas) MNHN6314 (25) Valle Platon (Rivera) Brazil LF952 (26) Taim Ecological Station (Rio Grande do Sul) Voucher Latitude Longitude Accession Number Number Argentina 12942 33[degrees]53'S 60[degrees]34'W KF917357 1874 37[degrees]17'S 59[degrees]58'W KF917358 1882 37[degrees]17'S 59[degrees]58'W KF917359 1297 38[degrees]41'S 59[degrees]45'W KF917360 1320 38[degrees]41'S 59[degrees]45'W KF917361 CNP 5053 38[degrees]11'S 59[degrees]00'W KX685933 CE21 31[degrees]30'S 63[degrees]54'W KF917362 CE29 31[degrees]30'S 63[degrees]54'W KF917363 CE32 31[degrees]30'S 63[degrees]54'W KF917364 SL2 33[degrees]20'S 66[degrees]14'W KF917365 SL26 33[degrees]20'S 66[degrees]14'W KF917366 NK15988 33[degrees]29'S 60[degrees]56'W AF385593 19328 33[degrees]16'S 60[degrees]42'W KF917368 21978 32[degrees]26'S 60[degrees]54'W KF917367 B18 29[degrees]16'S 59[degrees]52'W KF917369 37981 28[degrees]01'S 64[degrees]15'W KX685932 38779 32[degrees]24'S 59[degrees]44'W KX853855 Paraguay TK122109 23[degrees]04'S 59[degrees]15'W KF917374 NK72376 22[degrees]21'S 60[degrees]04'W AY033190 TK122274 22[degrees]04'S 59[degrees]58'W KF917375 TK66497 21[degrees]10'S 61[degrees]40'W KF917372 TK65638 20[degrees]03'S 61[degrees]51'W KF917371 TK67304 19[degrees]50'S 58[degrees]45'W KF917373 Bolivia NK25158 21[degrees]38'S 62[degrees]34'W AY033189 NK25156 21[degrees]38'S 62[degrees]34'W AF385594 Uruguay MNHN5311 34[degrees]41'S 56[degrees]20'W KX685935 PV52 34[degrees]35'S 56[degrees]42'W KF917378 PV54 34[degrees]35'S 56[degrees]42'W KF917379 MNHN7962 33[degrees]55'S 58[degrees]24'W KX685936 MNHN7963 32[degrees]11'S 57[degrees]30'W KX685937 MNHN7156 30[degrees]28'S 57[degrees]28'W KX685934 MNHN6314 30[degrees]57'S, 55[degrees]43'W KX685938 Brazil LF952 32[degrees]29'S 52[degrees]34'W AY964052 Voucher Source Haplotype Number Argentina 12942 INEVH 22 1874 INEVH 20 1882 INEVH 21 1297 INEVH 18 1320 INEVH 19 CNP 5053 CNP 20 CE21 MZ-UNC 15 CE29 MZ-UNC 14 CE32 MZ-UNC 17 SL2 DAE 16 SL26 DAE 13 NK15988 MSB 4 19328 INEVH 11 21978 INEVH 12 B18 MZ-UNC 8 37981 INEVH 23 38779 INEVH 3 Paraguay TK122109 TTU 10 NK72376 MSB 6 TK122274 TTU 6 TK66497 TTU 6 TK65638 TTU 6 TK67304 TTU 9 Bolivia NK25158 MSB 7 NK25156 MSB 5 Uruguay MNHN5311 MNHN 2 PV52 INEVH 1 PV54 INEVH 1 MNHN7962 MNHN 1 MNHN7963 MNHN 1 MNHN7156 MNHN 1 MNHN6314 MNHN 1 Brazil LF952 MCMN 1 CNP: Coleccion de Mamiferos del Centro Nacional Patagonico, Chubut, Argentina. MNHN: Museo Nacional de Historia Natural de Montevideo, Uruguay. INEVH: Instituto Nacional de Enfermedades Virales Humanas, Pergamino, Buenos Aires, Argentina. MZ-UNC: Museo de Zoologia, Universidad Nacional de Cordoba, Cordoba, Argentina DAE: Departamento de Ecofisiologia Animal, Universidad Nacional de San Luis, San Luis, Argentina MSB: Museum of Southwestern Biology, University of New Mexico, Albuquerque, New Mexico, USA TTU: Museum of Texas Tech University, Lubbock, Texas, USA MCMN: Mammal Collection of the Museu Nacional, Rio de Janeiro, Brazil.