Myotis barquezi, Novaes & Cláudio & Díaz & Wilson & Weksler & Moratelli, 2022

Novaes, Roberto Leonan M., Claudio, Vinicius C., Diaz, M. Monica, Wilson, Don E., Weksler, Marcelo & Moratelli, Ricardo, 2022, Argentinean Myotis (Chiroptera, Vespertilionidae), including the description of a new species from the Yungas, Vertebrate Zoology 72, pp. 1187-1216 : 1187

Myotis barquezi sp. nov.

Holotype.

Dried skin, skull, and mandible of an adult female (CML 7623; Figs 2 and 3 ), collected by M. D. Miotti (field number 540) on September 14, 2006. The specimen is deposited in the Colección Mamíferos Lillo (CML, Tucumán, Argentina).

Type locality.

Finca Alto Verde, ca. 20 km SW San Ramón de La Nueva Orán, Orán Department, Salta Province, Argentina (23°13′S, 64°32″W; 670 m elevation).

Paratype.

Dried skin, skull and mandible of an adult female (CML 7622), collected by M. D. Miotti (field number 539) on September 14, 2006 at the type locality.

Distribution and habitat.

Myotis barquezi is known only from the type locality, in Salta Province, northern Argentina, where it inhabits lowland tropical forests inside the Southern Andean Yungas ecoregion (Fig. 4 ). This vegetational domain is classified as tropical and subtropical moist broadleaf forest ( Olson et al. 2001) and is located between the Eastern slope of the Andes and the lowlands of the Alto Chaco ecoregion. The locality where M. barquezi was captured is close to Orán city and consists of a Premontane Forest ("selva pedemontana palo blanco and palo amarillo") of the Upper Bermejo River Basin distributed altitudinally between 400 and 900 m, with dominance of Calycophyllum multiflorum and Phyllostilon rhamnoides ( Jayat and Ortiz 2010). Some dominant species of trees in the area include pink lapacho ( Tabebuia impetiginosa ), pink cedar ( Cedrela balansae ), oak ( Amburana cearensis ), red cedar ( Anadenanthera colubrina ), cinchona ( Myroxylon peruiferum ), afata ( Cordia tricotoma ), palo lanza ( Patagonula americana ), and urundel ( Astronium urundeuva ) ( Brown 1995). The area is closely related to the Eastern Cordillera and the piedmont forest reaches only 700 m, bordering extensively with the Montane Forest of Argentina and Bolivia; to the east it is bordered by areas of highly disturbed Premontane Forests and highland Chaco environments ( Jayat and Ortiz 2010).

The climate presents hot, rainy summers and cold, dry winters, and the annual mean temperature exceeds 21°C ( Adámoli et al. 1972; Ojeda and Mares 1989). Summer temperatures (December to March) may approach 40°C, whereas winter minima (June to September) are near 6°C; annual rainfall mean ranges from 500 to 800 mm ( Adámoli et al. 1972; Cabrera 1976; Ojeda and Mares 1989). During the cooler months, the condensed water mist that characterizes these "cloud forests" is captured and cooperates to partially compensate for the lack of rains in that season ( Burkart et al. 1999).

Etymology.

Myotis barquezi is named in honor of Dr. Rubén M. Barquez, in recognition of his outstanding contributions to Neotropical mammalogy, especially on the bat fauna from Argentina. This species name is a noun in the genitive case formed by adding -i to the stem of the name (ICZN, 1999; 31.1.2).

Common name.

Barquez’s Myotis [English]; Myotis de Barquez [Spanish].

Diagnosis.

Small to medium sized species (FA 35.1-35.2 mm; GLS 13.1-13.5 mm); sagittal crest present but low; robust and broad skull; braincase inflated and remarkably high in lateral profile; braincase roof formed by the parietal bone strongly inclined forward; frontal bone with a slight slope towards the rostrum; posterior region of the braincase flattened and non-projected beyond the limit of the occipital condyles; well-developed mastoid processes; dorsal fur moderately long (LDF 5-6 mm), woolly and clearly bicolored, with tips ranging from Dresden Brown to Snuff Brown, and darker bases (Natal Brown); legs and dorsal surface of the uropatagium covered by fur that extend up to the knees or just beyond; plagiopatagium inserted into the foot by a broad band of membrane.

Morphological description and comparisons.

Myotis barquezi is a small to medium species of Myotis (Table 3 ), and fur texture and cranial morphology reassembles species allocated to the Myotis ruber -group (q.v., Moratelli et al. 2013, 2019a). Ears dark brown and comparatively medium-sized (EL 13-15 mm), reaching the portion of the rostrum between the eyes and nostrils when extended forward. Tragus long and slender, with a wide base and narrower spear-shaped terminal half, almost straight anterior edge, and rounded tip. Similar to M. armiensis and M. keaysi , membranes are Bone Brown, the dorsal surface of elbow, tibia, and uropatagium are densely furred, with hairs extending to the level of the knees or just beyond. The uropatagium lacks the fringe of hairs along the trailing edge. Plagiopatagium attached to the foot at the level of the toes by a broad band of membrane; toe nails are light brown.

Dorsal and ventral fur woolly and medium-sized (LDH 5-6 mm, LVH ~4.5 mm). Dorsal pelage clearly bicolored with medium-brown bases (near Natal Brown) and reddish tips, ranging from Dresden Brown to Snuff Brown. Darker bases comprise 2/3 of total hair length and changes abruptly from darker to lighter, with lighter tips comprising about 1/3 of hair length. Ventral pelage is also strongly bicolored, with Natal Brown bases (2/3 of hair length) and bright orangish tips (1/3 of hair length [near Clay Color]). The orangish venter contrasts with the reddish-brown dorsum.

Dental formula is I 2/3, C 1/1, PM 3/3, M 3/3 (2x) = 38, typical of most species of Myotis . Skull robust and medium-sized in length, resembling Myotis species of the Myotis ruber -group (GLS 13.1-13.5 mm). The second upper premolar (P3) aligned with toothrow, not displaced to the lingual side, and barely smaller than first upper premolar (P2). First lower molar (m1) myotodont, with postcristid connecting hypoconid and entoconid ( Menu 1987). Braincase robust and globose; sagittal and lambdoidal crests presents, but sagittal crest does not reach the posterior edge of the skull or join the lambdoidal crests, although there is a triangular-shaped elevation between them; occipital region flattened and not projecting beyond the posterior limits of occipital condyles; well-developed mastoid processes. Frontal bone slightly sloping; rostrum comparatively short.

Myotis barquezi can be distinguished from all the species in the Myotis ruber -group ( Myotis armiensis , Myotis elegans , Myotis keaysi , Myotis midastactus , Myotis moratellii , Myotis pampa , Myotis pilosatibialis , Myotis riparius , Myotis ruber , and Myotis simus ), and species from the Myotis albescens -group that confirmedly or potentially occur in the South American southern cone ( Myotis albescens , Myotis chiloensis , Myotis dinellii , Myotis izecksohni , Myotis lavali , Myotis levis , Myotis nigricans , and Myotis oxyotus ), by the set of diagnostic traits reported above.

Among species from the Myotis ruber -group, M. barquezi most resembles M. keaysi from the Central Andes (see Novaes et al. 2021b), but it is much smaller, and differs in all external and cranial dimensions (e.g., FA> 38 mm and GLS> 13.5 mm in M. keaysi ; whereas FA ~ 35 mm and GLS <13.5 mm in M. barquezi ), it also has shorter fur, and a lower sagittal crest. In addition, M. barquezi differs conspicuously from M. keaysi from Argentina by its reddish fur color, in contrast to brownish in M. keaysi populations from Argentina.

Myotis barquezi differs from M. ruber by its smaller size (both external and cranial; FA> 37.5 mm and GLS> 14.0 mm in M. ruber ), shorter and clearly bicolored dorsal fur, dense fur along the leg and dorsal surface of the uropatagium, narrower interorbital constriction, and more developed mastoid processes. It differs from M. armiensis by its smaller size (FA> 36.0 mm in M. armiensis ), clearly bicolored dorsal fur, lower sagittal crest, posterior region of the braincase flattened and non-projected beyond the limit of the occipital condyles. It differs from M. pilosatibialis by its smaller size (both external and cranial; FA> 36.0 mm in M. pilosatibialis ), clearly bicolored dorsal fur, globose braincase (elongated in Myotis pilosatibialis ), parietal bone strongly inclined forward, and shorter and broader rostrum. It differs from M. moratellii by its general smaller size (FA> 35.0 and GLS> 13.8 in Myotis moratellii ), clearly bicolored dorsal fur, braincase lower in profile, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles, and sagittal crest lower.

Myotis barquezi can be distinguished from M. riparius by its clearly bicolored and reddish dorsal fur, presence of dense fur along the leg and dorsal surface of the uropatagium, parietal bone strongly inclined forward, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles, narrower interorbital constriction, and more developed mastoid processes. It differs from M. elegans by its larger size (both external and cranial; FA <34.5 mm and GLS <13.0 mm in M. elegans ), more robust skull, higher sagittal crest, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles, narrower interorbital constriction, and more developed mastoid processes. It differs from M. pampa by its shorter fur (LDF <6 in M. barquezi , LDF> 7 in M. pampa ), ventral fur bicolored (being tricolored in M. pampa ), skull more robust, sagittal crest present, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles, and more developed mastoid processes.

Myotis barquezi can be easily distinguished from M. simus and M. midastactus by its smaller size (FA> 36.0 mm and GLS> 13.5 mm in M. simus and M. midastactus ), longer and clearly bicolored dorsal fur (being shorter [LDF <4] and unicolored in M. simus and M. midastactus ), legs and dorsal surface of the uropatagium covered by fur that extend up to the knees, plagiopatagium inserted into the foot by a broad band of membrane (attached at ankles in M. simus and M. midastactus ); and narrower skull. In addition, tympanic bullae are comparatively larger in M. barquezi than in any other species from Myotis ruber -group, except M. elegans .

In comparison to the species from the Myotis albescens -group, M. barquezi can be easily distinguished from M. albescens by the absence of a fringe of hairs on the posterior margin of the uropatagium, reddish dorsal fur clearly bicolored (brownish with frosted appearance in Myotis albescens ), yellowish ventral fur (whitish in Myotis albescens ), frontal bone slightly sloping, sagittal crest present, and posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles. It differs from M. dinellii and M. levis by its smaller size, absence of a fringe of hairs on the posterior margin of the uropatagium, comparatively shorter ears, narrower skull, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles. It differs from M. izecksohni and M. nigricans by the reddish and clearly bicolored dorsal fur, parietal bone strongly inclined forward, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles, and well-developed mastoid processes.

Myotis barquezi can be distinguished from M. chiloensis from its general smaller size (FA <35.2 in M. barquezi ; FA> 37 mm in M. chiloensis ), ventral fur strongly bicolored with bright orange tips, shorter and broader skull, less inflated braincase, parietal bone strongly inclined forward, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles. It differs from M. lavali by its shorter and reddish fur, broader skull, parietal bone strongly inclined forward, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles, and well-developed mastoid processes. Differs from M. oxyotus by its smaller size (FA> 37 mm), shorter dorsal fur, ventral fur strongly bicolored with bright orange tips, shorter and broader skull, broader skull, parietal bone strongly inclined forward, posterior region of the braincase flattened and not projected beyond the limit of the occipital condyles. In addition, M. barquezi can be distinguished from all species of the Myotis albescens -group by its woolly fur (silky fur in Myotis albescens -group species, except M. chiloensis ), dense fur on dorsal surface of the uropatagium (absent in all species of Myotis albescens -group), and tympanic bullae comparatively larger.

Remarks.

The specimens used here to describe M. barquezi (CML 7622 and 7623) were originally misidentified as Myotis lavali ( Barquez et al. 2017: 291).

Other Myotis species from Argentina

Figures

Figure 2. Dorsal (A) and ventral (B) views of the skin of the holotype of Myotis barquezi (CML 7623).

Figure 3. Dorsal, ventral and lateral views of the skull, and lateral view of the mandible of the holotype of Myotis barquezi (CML 7623). Scale bar = 10 mm.

Figure 4. Map of part of South America with type locality of Myotis barquezi (red star).