Molecular and morphological data suggest a new species of big-eared bat (Vespertilionidae: Corynorhinus) endemic to northeastern Mexico Author López-Cuamatzi, Issachar L. Centro de Investigaciones Tropicales, Universidad Veracruzana, Xalapa de Enríquez, Veracruz, Mexico, Author Ortega, Jorge Author Ospina-Garcés, Sandra M. Centro de Investigaciones Tropicales, Universidad Veracruzana, Xalapa de Enríquez, Veracruz, Mexico, & Centro de Investigación en Biodiversidad y Conservación, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexic Author Zúñiga, Gerardo Departamento de Zoología, Instituto Politécnico Nacional, Escuela Nacional de Ciencias Biológicas, Mexico City, Mexico, & @ aol. com (JO); cmacswiney @ uv. mx (MCMG) Author G., M. Cristina MacSwiney text PLoS ONE 2024 e 0296275 2024-02-21 19 2 1 35 journal article 10.1371/journal.pone.0296275 6237f2fd-84d2-4c9d-9984-e14473d561f8 1932-6203 10779341 Corynorhinus leonpaniaguae sp. nov. urn:lsid:zoobank.org:act: 98B459DC-ADF6-4F7A-88A7-8F5FEAC58C10 Vernacular name: León Paniagua’s Big-eared Bat, Murciélago-mula de León-Paniagua ( Spanish ) Synonyms. Corynorhinus macrotis pallescens Miller, 1897 , (Part) Corynorhinus megalotis mexicanus Allen, 1916 Corynorhinus rafinesquii mexicanus Miller, 1924 , (Part) Plecotus rafinesquii mexicanus Dalquest, 1953 , (Part) Plecotus mexicanus Handley, 1959 Corynorhinus mexicanus G. M. Allen, 1916 , (Part) Holotype . Colección de Mamíferos, Museo de Zoología Alfonso L. Herrera ( MZFC-M ), No. MZFC-M16326 is an adult female with skin and skull dry preserved and collected on April 18 th , 2022 , by Juan Cruzado , Silvino Hernández and Issachar L. López-Cuamatzi ( Fig 12 ). Fig 12. Holotype pictures. Coloration of the dorsal and ventral fur of the holotype (MZFC-M16326) of Corynorhinus leonpaniaguae sp. nov. (A, B). Cranium, mandible (C, D, E) and lateral view of the first upper double-cuspid incisor (F) of the holotype. https://doi.org/10.1371/journal.pone.0296275.g012 Type locality. Cave El Hundido ( 25.16096 , -100.622985 ; 2072 msnm), 2.5 Km NE from Puerto Grande , Galeana , Nuevo León , Mexico . Etymology. Corynorhinus leonpaniaguae is named in honor of Dr. Livia S. León Paniagua, in recognition of her outstanding contribution to the knowledge of the systematics and natural history of Mexican mammals. In addition to being a pioneering woman in Mexican mammalogy, Livia has been a great mentor, dedicated to the training of new scientists. This species name is a noun in the genitive case formed by adding -ae to the stem of the name [ 110 ]. Habitat and distribution. Corynorhinus leonpaniaguae lives in open pine forests located on slopes and canyons of the northern Sierra Madre Oriental and mountains of the state of Coahuila . Records of the presence of this species occur mainly between 300 and 2000 meters above sea level (masl) in the states of Coahuila , Nuevo León , and Tamaulipas . It is an endemic species of Mexico with distribution restricted to the northeast of the country ( Fig 13 ). In the localities of Galeana, Nuevo León , and Sierra de Zapalinamé in Arteaga, Coahuila , specimens were captured in sites close to forests where globose and cylindrical cacti are present. Other plant species present are Pinus cembroides , Pinus sp , Juniperus sp , Yucca filifera , Y . linearifolia , and Yucca carnerosana . The characteristics of the roosts used by this species are unknown; however, in Coahuila , one specimen was captured during the day inside an abandoned mine, and, in Nuevo León , a colony with pregnant females was found in a limestone, dolomite, and gypsum cave. Fig 13. Historical records of the presence of Corynorhinus mexicanus and Corynorhinus leonpaniaguae sp. nov. The Mexican administrative boundaries layer was downloaded from the GADM (https://gadm.org/ downloadcountryv3.html). https://doi.org/10.1371/journal.pone.0296275.g013 Description and comparison. The specimens from Nuevo León present a brownish to grayish colored dorsal fur with dark bases and slightly lighter tips that appear to contrast between bands. However, this contrast is not equivalent to that observed in Corynorhinus townsendii ( Fig 14 ). Like C . mexicanus and C . rafinesquii , C . leonpaniaguae presents a double cuspid in the first upper incisor ( Figs 12 and 14 ). Its dental formula is i 2/3, c 1/1, p 2/3, and m 3/3, with a total of 36 teeth in its adult stage. The average values of cranial measurements and external measurements for females and males are reported in Table 4 . In external appearance, it is similar to and is almost indistinguishable from C . mexicanus specimens from the Sierra Madre Occidental (SMOC). Corynorhinus leonpaniaguae is distinguished from C . townsendii because the latter presents a tragus of> 13 mm and a naked uropatagium with ten or more interfemoral grooves, while the former presents a tragus of < 13 mm and a hairy uropatagium with nine or fewer interfemoral grooves. Moreover, C . townsendii usually has a larger forearm ( 39 to 47 mm ) and cranium maximum length ( 15.2 to 17.3 mm ) than C . leonpaniaguae . In external appearance, C . leonpaniaguae is also similar to C . rafinesquii ; however, C . leonpaniaguae has bicolored ventral fur with brown bases and light tips, while C . rafinesquii has more contrasting fur due to the presence of hairs with black bases and white tips. Fig 14. Comparison between C . mexicanus , C . leonpaniaguae , and C . townsendii . Specimens shown correspond to C . mexicanus from (A) Puebla (ENCB27986), (B) Tlaxcala (ENCB4405), and (C) Durango (CRD11777); C. leonpaniaguae from the cave of San Josecito, in Gral. Zaragoza, Nuevo Leon, Mexico (D- CRD11774; E- CRD11778; and F- CRD11777). Specimen of C . townsendii from Durango (G- CRD4831). Some differences in color bands on the dorsal fur are shown for C . leonpaniaguae (H), C . mexicanus (I), and C . townsendii (J). Double-cuspid on upper incisor tooth (white arrow) observed in C . leonpaniaguae (K), C . mexicanus (L), and C . townsendii (M). https://doi.org/10.1371/journal.pone.0296275.g014 Geographic variation. With the restricted distribution and limited sample size, it was not possible to detect morphological variation associated with geography. Only two haplotypes of Cyt- b sequences have been detected within Corynorhinus leonpaniaguae . Subspecies. Corynorhinus leonpaniaguae is a monotypic species. Table 4. Morphological measurements of external structures obtained in Corynorhinus leonpaniaguae .

Females	Males
Mean	SD	Range	CV	Mean	SD	Range	CV
Maximum length	14.87	0.34	14.19–15.20	2.28	15.10	0.31	14.8–15.68	2.05
Zygomatic width	7.94	0.36	7.05–8.37	4.60	8.08	0.24	7.79–8.38	3.01
Postorbital width	3.36	0.08	3.24–3.49	2.43	3.36	0.12	3.17–3.54	3.64
Width of the braincase	7.73	0.27	7.33–8.07	3.43	7.72	0.34	7.35–8.38	4.44
Maxillary toothrow length	4.74	0.08	4.67–4.94	1.78	4.69	0.07	4.60–4.80	1.47
Width between upper molars	5.82	0.11	5.66–5.96	1.88	5.74	0.16	5.57–5.97	2.78
Total length	91.59	5.73	84.37–102.79	6.25	90.56	6.00	82.08–101.14	6.62
Tail length	43.37	6.15	34.95–55.75	14.19	40.12	3.53	35.20–44.91	8.79
Ear length	28.66	1.24	27.37–30.43	4.33	28.43	1.39	27.13–31.30	4.89
Tragus length	10.89	0.93	9.54–12	8.54	10.23	0.80	8.69–10.79	7.80
Forearm length	41.91	1.48	38.71–43.94	3.54	40.52	0.99	39.54–42.08	2.44
Mean, standard deviation (SD), range, and coefficient of variation (CV) values are shown. Measurements are reported in millimeters (mm).

https://doi.org/10.1371/journal.pone.0296275.t004 Natural history. There is no published information documenting the natural history of this species. Some observations made during the fieldwork of this study suggest certain aspects of the biology of Corynorhinus leonpaniaguae . In two expeditions conducted in August 2021 and April 2022 at the type locality of this species, several specimens of Myotis thysanodes , Corynorhinus townsendii , Leptonycteris nivalis , Idionycteris phyllotis , and Antrozous pallidus were captured. These specimens were captured at the entrance of the El Hundido Cave both entering and exiting the cave. This suggests that Corynorhinus leonpaniaguae may share its roosts with these species. Of those mentioned above, M . thysanodes and C . townsendii were the only species, apart from Corynorhinus leonpaniaguae , that were captured on both field trips, indicating that all three species are probably residents of the cave. In August 2021 , four juvenile male individuals were captured, indicating that weaning of these specimens had occurred in June-July, which is similar to that reported for C . mexicanus [ 39 ]. In April 2022 , twelve adult females in an advanced state of pregnancy were captured, suggesting that births probably occur between the end of April and mid-May. All specimens captured in May and August presented a considerable number of ectoparasitic flies, presumably of the Trichobius corynorhini species. The acoustic characteristics of Corynorhinus leonpaniaguae were obtained from ten specimens recorded using the hand-release technique and an Echo Meter Touch 2 Pro bat detector. Recordings were analyzed with the Batsound 1 software using Hanning window and 2048 of FFT size. Two sonotypes composed of modulated and harmonic pulses were observed from the recordings ( Fig 15 ). The first sonotype consisted of combinations of two pulses repeated serially with a longer time interval between combinations than between the pulses in the combination. Although two-pulse combinations were predominant, three-pulse combinations were observed in some specimens. The second sonotype was characterized by the absence of pulse combinations and the presence of modulated pulses of longer duration. Details of frequency, duration, and interval are presented in Table 5 . Differences in acoustic characteristics among the species of Corynorhinus are still unknown.