Expanding the knowledge of the bat fauna of the Brazilian Caatinga: new geographical records of molossid bats (Chiroptera, Molossidae) for the Chapada Diamantina region, with taxonomic notes Author García, Franger J. 0000-0001-6764-225X Programa de Pós-graduação em Zoologia, Universidade Estadual de Santa Cruz, Ilhéus, Brazil Author Ochoa-G, José https://orcid.org/0009-0000-4095-0463 Centro de Estudios en Zoología Aplicada (CEZA), Facultad de Ciencias y Tecnología, Universidad de Carabobo, Valencia, Venezuela Author Poma-Urey, José L. 0000-0002-2426-9819 Área de Zoología, Museo de Historia Natural Noel Kempff Mercado de la Universidad Autónoma Gabriel René Moreno, Santa Cruz, Bolivia Author Miller, Bruce W. 0000-0001-5719-1942 Neotropical Bat Acoustic and Risk Assessments, 11384 Alpine Rd., Canadian Lakes, MI 49346, USA Author Falcão, Fábio C. 0000-0002-2748-7117 Tetrapoda Consultoria Ambiental Ltda, Ilhéus, Bahia, Brazil Author del Valle Alvarez, Martín Roberto 0000-0001-6908-8547 Programa de Pós-graduação em Zoologia, Universidade Estadual de Santa Cruz, Ilhéus, Brazil text ZooKeys 2024 2024-08-29 1210 333 371 journal article 10.3897/zookeys.1210.128570 9D29FB86-005C-4D6C-AA62-85314A59C419 Molossops temminckii (Burmeister, 1854) Summary of captures. One female ( CMARF 2144) and one male ( CMARF 2145). External measurements and weights. Female: TLB : 85.00, TL : 33.00, LHL : 5.00, EL : 12.00, W: 6.00. Male: TLB : 80.00, TL : 28.00, LHL : 5.00, EL : 13.00, W: 6.00. Morphological description. Dorsal pelage is chestnut-brown at the tips and yellow at the bases, while ventrally, the coloration is slightly paler (Fig. 8 ). Ears triangular, with a small and triangular tragus. Antitragus broad and slightly inclined posteriorly. Snout elongated, flat, wide, and blunt, featuring a slightly prominent tip and an obtuse projection between the nasal orifices. Lips smooth and bordered by a fine fringe of hook-shaped hairs, accompanied by a tuft of bristles below the nostrils. Small warts or papillae are notably present on the upper edge of the nostrils. Dorsal, ventral, and lateral views of the skull of a female (CMAR 2144 A, C upper) and a male ( CMARF 2145 B, C lower) of Molossops temminckii collected in the Caatinga, northeastern Brazil D external body features of a female of Molossops temminckii from the same locality. Scale bar 5 mm. Skull with dorsoventral flattening (Fig. 8 ), characterized by an elevation extending from the nasal tip to the posterior part of the braincase. Postorbital constriction is prominently defined, accompanied by deep lacrimal canals. The sagittal crest is distinctive, reaching its peak at the junction with a well-developed lambdoidal crest. Tympanic bullae small. Basisphenoid pits are shallow. Third upper molar is well-developed in the female, surpassing the maxillary bone (Fig. 9 ). Third upper molar is less developed in the male, not extending beyond the maxillary bone (Fig. 9 ). Lower incisors are bilobed. Some skull measurements are shown in Table 1 . Magnified view (not to scale) of upper molar teeth in specimens of Molossops temminckii , showing the sexual dimorphism in the development of the third molar indicated with white arrows ( A female B male). Identification. The relatively small size (forearm < 33 mm ) and condylobasal length < 15 mm allowed for the assignment of the denomination M. temminckii to the specimens referred to here, distinguishing them from the only known congener in Brazil ( M. neglectus S. L. Williams & Genoways, 1980 ), whose reported distribution corresponds to the southeastern region ( Gregorin et al. 2020 ). Molossops griseiventer Sanborn, 1941 a taxon recently validated as a full species ( Ramírez-Chaves et al. 2023 ), has an Andean distribution in Colombia . It can be differentiated from M. temminckii by the less pronounced shape of the nasal septum. However, it is important to consider that Ramírez-Chaves et al. (2023) did not provide information on sex differences in their comparisons. The variations between M. temminckii and M. griseiventer , suggested by Ramírez-Chaves et al. (2023) , could be related to sexual dimorphism, as reported in our study. These authors compared both species without considering the marked sexual dimorphism in Molossidae ( Eger 2008 ) ; future studies could clarify the possible separation between M. griseiventer and M. temminckii . <emphasis id="566503EFFBE27D091E657C00E08A1BAF" italics="true">Molossops</emphasis> sp. Summary of captures. One female ( CMARF 2146). External measurements and weight. TLB : 71.00, TL : 21.14, LHL : 4.87, EL : 11.03, W: 6.60. Morphological description. The dorsal pelage is chocolate brown at the tips and yellow at the base, while the coloration is slightly paler ventrally. Ears triangular, with small and triangular tragus. Antitragus broad and slightly inclined posteriorly. Snout elongated, flat, wide, and blunt, featuring a slightly prominent tip and an obtuse projection between the nasal orifices. Lips smooth and bordered by a fine fringe of hook-shaped hairs, accompanied by a tuft of bristles below the nostrils. The skull exhibits dorsoventral flattening, with a slight elevation from the tip of the nasals to the back of the braincase. Postorbital constriction is prominently defined, accompanied by deep lacrimal canals. The sagittal crest is present but is low at the junction with the lambdoidal crest. Lambdoidal crest weakly developed. Tympanic bullae are small, and the basisphenoid pits are shallow. The third upper molar has two well-developed posterior commissures, surpassing the maxillary bone. Lower incisors are trilobed. Some skull measurements are shown in Table 1 . Identification. The presence of three-lobed lower incisors and two well-developed posterior commissures in the third upper molar, surpassing the maxillary, represent unique characteristics that differentiate this specimen from the two specimens previously assigned to Molossops temminckii or its other congener, Molossops griseiventer .