New insights into the distribution of Myotis riparius Handley, 1960 (Mammalia, Chiroptera) in northern Central America: first records for Guatemala, Belize, and El Salvador

the journal of biodiversity data NOTES ON GEOGRAPHIC DISTRIBUTION 930 Academic editor: Guilherme Garbino Received: 24 June 2025 Accepted: 6 October 2025 Published: 10 October 2025 Copyright © The authors. This is an open‑access article distributed under terms of the Creative Commons Attribution License (Attribution 4.0 International – CC BY 4.0) Abstract. We provide new records of Myotis riparius Handley, 1960, expanding its known range in northern Central America. These include the first confirmed records for Guatemala, Belize, and El Salvador, as well as new localities in Honduras and Nicaragua. An individual was collected in Bocas del Polochic Wildlife Refuge, Izabal, Guatemala. Acoustic vouchers confirm its presence in the Maya Mountains of Belize and Ahuachapán and Sonsonate, El Salvador. This finding highlights the importance of combining capture and acoustic sam‑ pling, and reanalyzing archived recordings as new vocal signatures are validated. Key words. Bioacoustics, geographic distribution, range extension, Vespertilionidae Trujillo LA, Miller B, Ordoñez-Mazier DI, Salguero D, Ávila-Palma H, Estrada N, Mansilla D, Hooper K, Alvarez W, Martínez-Fonseca JG (2025) New insights into the distribution of Myotis riparius Handley, 1960 (Mammalia, Chiroptera) in northern Central America: first records for Guatemala, Belize, and El Salvador. Check List 21 (5): 930–939. https://doi.org/10.15560/21.5.930 INTRODUCTION The genus Myotis Kaup, 1829, is among the most species‑rich mammalian genera, comprising over 140 rec‑ ognized species worldwide (Moratelli et al. 2019b; MDD 2025; Simmons and Cirranello 2025). In the Neo‑ tropics, the genus exhibits both high species richness and remarkable diversification, including numerous endemic taxa (Carrión‑Bonilla et al. 2024; Moratelli and Wilson 2011, 2014; Moratelli et al. 2011, 2013, 2016, 2017, 2019a, 2019b; Novaes et al. 2021, 2022a, 2022b, 2023, 2024). In Central America, Myotis is the most diverse bat genus, with 14 recognized species documented to date (Owen and Girón 2012; Martínez‑Fonseca et al. 2020; Turcios‑Casco et al. 2020; Ramírez‑Fernández et al. 2023; Trujillo et al. 2024; Simmons and Cirranello 2025). Central America encompasses a wide range of ecological and elevational gradients, supporting a high diversity of Myotis throughout the region. Guatemala harbors the highest richness, with 11 species, including the endemic M. cobanensis Goodwin, 1955, and several North American taxa that reach their southernmost limits in the country (Kraker‑Castañeda et al. 2016; Trujillo et al. 2024). Panama and Costa Rica each host seven species, while Honduras supports six, Nicaragua five, El Salvador four, and Belize only two (Owen and Girón 2012; Martínez‑Fonseca et al. 2020; Miller 2003b, 2009; Turcios‑Casco et al. 2020; Simmons and Cirranello 2025). Among the species reported in Central America is the Riparian Myotis, Myotis riparius Handley, 1960, a widely distributed Neotropical bat ranging from Olancho, Honduras to Buenos Aires, Argentina. This broad latitudinal range reflects its remarkable ecological plasticity, as the species occurs in habitats from lowland and montane forests to savannas and even human‑modified environments such as agricultural fields and pastures (Barquez et al. 2011). Although M. riparius is known from sea level to about 2,000 m in elevation, most records come from lowland areas (Reid 2009; Barquez et al. 2016; Novaes et al. 2017). Despite this ex‑ tensive distribution, the species had not previously been confirmed for Guatemala, Belize, or El Salvador, 21 (5) · https://doi.org/10.15560/21.5.930 21 (5): 930–939 New insights into the distribution of Myotis riparius Handley, 1960 (Mammalia, Chiroptera) in northern Central America: first records for Guatemala, Belize, and El Salvador Luis A. Trujillo1, 2, Bruce Miller3, Diego I. Ordoñez-Mazier4, 5, Diana Salguero1, 2, Hefer Ávila-Palma6, Nereyda Estrada7, Diana Mansilla1, 2, Katarina Hooper2, Walter Alvarez-Jacinto1, José G. Martínez-Fonseca8 1 Fundación Defensores de la Naturaleza, Guatemala City, Guatemala 2 Escuela de Biología, Universidad de San Carlos de Guatemala, Guatemala City, Guatemala 3 Neotropical Bat Acoustic Assessments, Canadian Lakes, Michigan, USA 4 Asociación Para La Sostenibilidad e Investigación Científica en Honduras (ASICH), Francisco Morazán, Honduras 5 Department of Behavioral Ecology, Faculty of Biological Sciences, University of Wrocław, Sienkiewicza, Wrocław, Poland 6 PANTHERA, Tegucigalpa, Honduras 7 Escuela de Biología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras 8 School of Forestry, Northern Arizona University, Flagstaff, Arizona, USA Corresponding author: Luis A. Trujillo (trujillososalui[email protected]om) Check List 21 (5) · https://doi.org/10.15560/21.5.930 Trujillo et al. · Myotis riparius in northern Central America 931 underscoring the existence of significant gaps in the distributional and taxonomic knowledge of the genus in northern Central America. Although M. riparius remains poorly documented in northern Central America, recent discoveries from South America, such as the range extension reported by Bocchiglieri and Bezerra (2018) in the Atlantic For‑ est of northeastern Brazil, continue to refine the species’ known distribution and underscore its remarkable ecological plasticity across the Neotropics. Species distribution models indicate that M. riparius is primarily associated with forested habitats and reveal pronounced discontinuities among populations across South American ecoregions. This spatial separation suggests that the species once formed a widespread, pan‑ mictic metapopulation that fragmented during the Middle Pleistocene, likely in response to climate‑driven environmental shifts (Novaes et al. 2023). The recognition of at least four allopatric or parapatric cryptic evolutionary units further raises the possibility that Mesoamerican populations represent distinct lineages from those in South America (Novaes et al. 2023). To address existing distributional and taxonomic gaps, we present the first confirmed record of M. riparius, in Guatemala, based on a collected specimen from the Bocas del Polochic Wildlife Refuge. We also report the first verified records for Belize and El Salvador, supported by acoustic vouchers from the southern V.a Mountains and the departments of Ahuachapán and Sonsonate, respectively. In addition, we provide new acoustic detections from Honduras and Nicaragua, extending the known distribution of M. riparius beyond previously documented localities (GBIF 2025). Collectively, these records clarify the northern limits of the species and underscore the importance of integrating acoustic monitoring into regional assessments of Myotis diversity, particularly in under‑sampled areas (O’Farrell and Gannon 1999). METHODS Field records were obtained in the Reserva Natural Privada Selempim within the Refugio de Vida Silves‑ tre Bocas del Polochic, Izabal, Guatemala,, an area of humid tropical forest located along the transition between lowland Caribbean floodplains and premontane slopes (Fundación Defensores de la Naturaleza 2003; IARNA‑URL 2018). In Belize, acoustic vouchers confirmed the presence of the species in the Maya Mountains, a region characterized by extensive evergreen and submontane forests at elevations ranging from 200 to 800 m (Meerman and Sabido 2001). In El Salvador, detections were concentrated in the depart‑ ments of Ahuachapán and Sonsonate, where remnant moist forests and riparian corridors persist within a mosaic of agricultural landscapes (Komar 2002). We compiled records from independent survey efforts in each country, including mist‑netting in Guate‑ mala and acoustic surveys in Belize, El Salvador, Honduras, and Nicaragua. In Guatemala, bats were captured using four mist nets of 12 m in length, set at ground level along natural flyways such as forest trails and water bodies, following the methodology described by Kunz and Parsons (2009). Nets were opened shortly be‑ fore sunset (approximately 17:30 h) and remained open for approximately 5 h. For each captured individual, morphometric data were recorded, including head and body length (HB), forearm length (FA), ear length (E), tail length (T), hindfoot length (HF), and body mass (Wt). Species identification was conducted in the field using diagnostic characters from Reid (2009), Medellín et al. (2008), and York et al. (2019), and followed current taxonomic criteria (Simmons and Cirranello 2025). All procedures adhered to the ethical guidelines of the American Society of Mammalogists (Sikes et al. 2016). The voucher specimen, comprising skin, skull, tissue, and photographic records, was deposited in the Mammal Collection of the Universidad de San Carlos de Guatemala (USAC). Specimen collection was conducted under permits issued by the Consejo Nacional de Áreas Protegidas (CONAP), as co‑administrators of the protected area (Government Decree No. 93‑93). Additionally, we conducted a comprehensive reassessment of archived acoustic voucher records in northern Central America to evaluate its potential occurrence within the species’ northern range. The anal‑ ysis was performed using the Acoustic Data Management System (ADMS), a relational database with cus‑ tom‑built modules for managing and analyzing more than two million bat call records collected between 1995 and 2025 across the Neotropics, with extensive coverage in Central America. The dataset was queried for verified M. riparius calls, files initially identified as sonospecies, and “Myotis‑like” sequences overlapping with the diagnostic characteristic frequency (Fc) of the dominant harmonic. Among the parameters used for species identification, the Fc of the dominant harmonic proved especially diagnostic, remaining consis‑ tent across full‑spectrum and zero‑crossing recordings and unaffected by recording amplitude or analytical configuration (Miller and Corben 2020; Corben 2025). To distinguish M. riparius from other Myotis species occurring in northern Central America, verified call parameters were compiled and compared in R (R Core Team 2025) to visualize diagnostic variation. A species‑specific Anabat filter was developed using frequency, temporal, and slope parameters, as well as the proportion of maximum frequency to characteristic frequen‑ cy (PMC), to exclude calls from species with partially overlapping frequency ranges (Corben 2022). The filter was applied to more than 1.5 million archived recordings, yielding approximately 6,000 candi‑ date files for manual review in AnalookW (v. 4.7.w; Corben 2025). Because multiple species can occur within Check List 21 (5) · https://doi.org/10.15560/21.5.930 Trujillo et al. · Myotis riparius in northern Central America 932 a single 15‑second call sequence, all flagged files were manually verified using split‑screen comparisons with confirmed M. riparius vouchers. Sequences matching the diagnostic acoustic profile were updated to “Myorip” in the metadata, while uncertain or fragmentary files were reassigned or left unclassified. Verified records were georeferenced and exported as point shapefiles in ArcGIS Pro (v. 3.5.3; Esri Inc. 2025) for spatial analysis. Visualization of these data revealed numerous verified acoustic records beyond the previously recognized range of M. riparius, prompting a reassessment of its distributional limits in northern Central America. A distribution map for M. riparius was generated using the species range provided by the International Union for Conservation of Nature (Barquez et al. 2016) as a base layer. Occurrence data available in the Global Biodiversity Information Facility (GBIF 2025) were used for reference; of the 1,803 records listed globally, only six were located within the northern portion of the range, corresponding to two localities in Honduras and four in Nicaragua (GBIF 2025). To complement this limited representation, we incorporated additional confirmed records from Nicaragua (Martínez‑Fonseca et al. 2020). All occurrence data were compiled and mapped in ArcGIS Pro v. 3.5.3 to visualize the updated northern distribution of the species (Figure 1). RESULTS Myotis riparius Handley, 1960 Figure 2 New records. GUATEMALA — Izabal• El Estor, Reserva Natural Privada Selempim, Refugio de Vida Sil‑ vestre Bocas del Polochic; 15.3244, −089.3867; 33 m elev.; 10.XII.2024; Luis A. Trujillo leg.; mist net set along a forest path in a small fragment of lowland tropical rainforest; HB 48.6 mm; FA 34.8 mm; E 12 mm; T 36 mm; HF 7 mm; Wt 5 g; 1♂, adult, sink, skull and tissues, USAC 6607. BELIZE —Toledo • CRFR Expedition Camp; 16.3817, −089.1208; 19–21.II.1997; BMW obs.; acoustic recording Figure 1. Updated distribution of Myotis riparius based on GBIF records (n = 1,803) and new confirmed localities in Guatemala, Belize, El Salvador, and Honduras. The newly documented records represent significant range extensions beyond previously verified occurrences. Check List 21 (5) · https://doi.org/10.15560/21.5.930 Trujillo et al. · Myotis riparius in northern Central America 933 • CRFR Expedition Camp 2; 16.38762, ‑89.09105; 18.II.1997; BMW obs.; acoustic recording. EL SALVADOR — ahuachapán • El Imposible National Park; 13.8262, −089.9473; 15.V.2003, 18.V.2003; BMW obs.; acoustic recording — SanTa ana • Volcano de Santa Ana; 13.8658, −089.6215; 14–16.V.2003; BMW obs.; acoustic recording. HONDURAS — GracIaS a dIoS • Mosquitia, Auka; 14.940, −083.8323; 37 m elev.; 21–25.VII.2021; MATC obs.; acoustic recording • Mosquitia, Mavita, Rus Rus; 14.7480, −084.4488; 70 m elev.; 9–10.XII.2024; MATC obs.; acoustic recording • Prahbani, Mosquitia; 15.2634, −083.7719; 11 m elev.; 22–24.VII.2021; MATC obs.; acoustic recording • Mosquitia, Tipi; 15.2634, −083.7719; 11 m elev.; 25–26.VII.2021; MATC obs.; acoustic recording — corTéS • San Pedro Sula, Parque Nacional Cusuco; 15.4961, −088.2122; 1,606 m elev.; 4.V.2021; HDAP obs.; acous‑ tic recording — ISlaS de la bahía • Guanaja, east end; 16.4885, −085.8290; 37 m elev.; 25–26.VII.2021; MATC obs.; acoustic recording — InTIbucá • Intibucá, Refugio de Vida Silvestre Mixcure; 14.9402, −088.1712; 1,951 m elev.; 2.III.2025; MATC obs.; acoustic recording. NICARAGUA — carazo • Santa Teresa, Rio La Chota; 11.5967, −086.1442; 47 m elev.; 8.XII.2024; JGMF obs.; FA 31mm; Wt 3.5 g; 1♂, adult, released — JInoTeGa • Macizo Peñas Blancas; 13.271, −085.7162; 1,067 m elev.; 14.III.2024; JGMF obs.; FA 35 mm; Wt 5 g; 1 ♂, adult, released — reGIón auTónoma coSTa carIbe norTe • Cerro Waylawás, near Siuna; 13.6452, −084.8139; 124 m elev.; 24.II.2024; JGMF obs.; FA 34 mm; Wt 4 g; 1♀, adult, released — reGIón auTónoma coSTa carIbe Sur • Kukra Hill, Greenfields; 12.2216, −083.7466; 5 m elev.; 24.III.2024; JGMF obs.; FA 33mm; Wt 5 g; 1♂, adult, released • Kukra Hill, Greenfields; 12.2216, −083.7466; 5 m elev.; 25.III.2024; JGMF obs.; FA 34mm; Wt 4 g; 1♂, adult, released. Morphological identification. Myotis riparius is currently recognized as a complex of at least four cryp‑ tic species exhibiting allopatric and parapatric distributions. The specimen examined in this study (Figure 2A) is morphologically distinguishable from closely related congeners in the region, including M. nigricans Schinz, 1821, M. extremus Miller & Allen, 1928 (Novaes et al. 2024), and M. pilosatibialis LaVal, 1973. Diagnostic features include the position of a small upper P3 displaced lingually relative to the tooth row (Figure 2B), and distinct differences in pelage and skin coloration (Reid 2009; Novaes et al. 2017). The dorsal fur of M. riparius is long and woolly, typically reddish‑brown to cinnamon, with sharply bicolored ventral hairs (dark bases and yellowish tips), a pattern that creates a strong contrast within the pelage (Figure 2C). This marked differenti‑ ation is distinctive when compared to the less‑contrasting, shorter, and darker pelage of M. nigricans, and to the paler, grayish tones with only subtle contrast in M. pilosatibialis. Additionally, facial skin pigmentation is a diagnostic trait: M. riparius shows a distinctive pinkish‑brown facial skin coloration (Figure 2A), contrasting with the blackish skin observed in M. nigricans and M. extremus. Finally, M. riparius can be separated from M. pilosatibialis by the near absence of hair on the uropatagium and feet, whereas M. pilosatibialis bears dense fur along the tibia extending onto the legs, feet, and tail membrane, a feature that readily distinguishes the two taxa. Acoustic identification. Field identification of M. riparius and M. pilosatibialis based on external mor‑ phology can be challenging due to their similar size and general appearance; however, the two species are readily distinguished by their echolocation calls (Figure 3). As demonstrated in prior studies, Myotis species Figure 2. Myotis riparius Handley, 1960 from Bocas del Polochic Wildlife Refuge, Guatemala (USAC 6607). A. Lateral view. B. Small upper P3 displaced toward the lingual side in relation to the tooth row. C.Ventral fur coloration. Check List 21 (5) · https://doi.org/10.15560/21.5.930 Trujillo et al. · Myotis riparius in northern Central America 934 that are difficult to differentiate morphologically can often be reliably identified by their vocal signatures (O’Farrell 1999). A comparison of the characteristic frequency (Fc) among all Myotis species potentially oc‑ curring in the region reveals clear separation between taxa (Figure 4). A summary of the vocal signature of M. riparius, based on confirmed calls from free‑flying individuals, is presented in Table 1. The diagnostic Fc, ranged from 54.05 to 56.74 kHz in 90% of recorded calls. This range matched the Fc values of the un‑ identified Myotis recorded in Belize in 1997 and El Salvador in 2003. These findings support the acoustic identification of M. riparius from archived voucher files and represent the first verified records of the species for both countries. Although call parameters allow reliable identification using Fc (Figure 4) in most cases, partial overlap V. occur within individual variation among other Myotis species of similar size, emphasizing the need for continued development of regional acoustic libraries to refine species‑level discrimination in northern Central America. DISCUSSION This study provides the first specimen of Myotis riparius from Guatemala, and first acoustic detection for the species in Belize and El Salvador, significantly extending the known northern distribution of the species in Central America. These records fill critical gaps in its documented range and expand its global distribu‑ tion by approximately 390 km northeastward into the Maya Mountains of Belize. Prior to this study, the northernmost verified occurrence was from Olancho, Honduras (GBIF 2025). In addition to refining distri‑ butional limits, these new records increase the number of documented bat species to 106 in Guatemala (Kraker‑Castañeda et al. 2016; Trujillo et al. 2020, 2021, 2024), 72 in Belize (Herrera et al. 2018), and 66 in El Salvador (Owen and Girón 2012). Our findings demonstrate that M. riparius is distributed more broadly across the northern Central Amer‑ ican region, encompassing Guatemala, Belize, El Salvador, and Honduras, within what has been referred to as Nuclear Central America (Schuchert 1935). This core area, lying between the Isthmus of Tehuantepec and the Nicaraguan depression, is characterized by a complex physiography that spans dry Pacific lowlands, interior valleys, and humid Caribbean slopes (McCarthy et al. 1993). The occurrence of M. riparius across this heterogeneous landscape indicates that the species is not constrained by sharp ecological barriers but in‑ Figure 3. Comparison of the two Myotis species recorded in the Maya Mountains clearly demonstrates differences in the frequency of maximum energy (Fc). Frequency is shown on a logarithmic scale, and time (in milliseconds) is displayed in compressed mode, with intervals between pulses visually removed. Table 1. Summary of key call parameters of M. riparius with the diagnostic Fc of the dominant harmonic bolded. In‑ cluded are values of where 90% of call pulses occur. Dur is pulse duration measured in ms, frequencies are in kHz, and the characteristic slope (Sc) is measured as octaves per second. Variable NMin. Max. Mean Std. dev. Median 90% Dur 145 2.08 6.70 3.77 1.12 3.56 5.36 Fmin 145 52.12 57.55 54.58 0.99 54.61 55.86 Fmax 145 58.39 108.11 74.20 13.41 69.57 96.39 Fmean 145 55.15 64.83 58.86 2.42 58.16 62.89 Fc 145 54.05 57.76 55.65 0.85 55.56 56.74 Sc 145 −34.19 104.91 31.26 28.11 33.55 62.91 Check List 21 (5) · https://doi.org/10.15560/21.5.930 Trujillo et al. · Myotis riparius in northern Central America 935 stead persists in diverse environments associated with water bodies and forest cover, from lowland riparian systems to submontane forests (Barquez et al. 2011). In this context, the species exemplifies broader biogeo‑ graphical patterns in a region where Nearctic, Neotropical, and Pan‑American faunal elements converge, underscoring both its ecological flexibility and the role of northern Central America as a transitional zone for bat assemblages (McCarthy et al. 1993; Barquez et al. 2016). Central America harbors a substantial proportion of the global range of M. riparius and represents both the northernmost and southernmost range boundaries for several taxa (Trujillo et al. 2024). Integrative anal‑ yses show that M. riparius is monophyletic but genetically structured into at least four cryptic evolutionary units with no haplotype sharing across populations (Novaes et al. 2023). Thus, the new Central American records are taxonomically important, as they help define the limits of northern lineages and provide an opportunity to reassess relationships both within the M. riparius complex and with other members of the ruber group, such as M. elegans and M. pilosatibialis (Novaes et al. 2023). The integration of multiple lines of evidence is essential for documenting and reassessing species boundaries in Myotis. In this regard, archived acoustic recordings play a role comparable to museum speci‑ mens, serving as time‑stamped vouchers that can be revisited as taxonomic knowledge advances (Miller et al. 2024). Their value is particularly evident for sequences originally identified only to the sono‑species level, which can later be reanalyzed as vocal signatures are validated and taxonomic frameworks refined. More‑ over, acoustic datasets extend beyond species diagnoses, as Ochoa et al. (2000) demonstrated that they also capture diagnostic features at higher taxonomic levels, including genera and families. From this perspective, acoustic vouchers complement morphological and genetic evidence, ensuring that past records remain sci‑ entifically relevant. Collectively, these elements underscore the enduring contribution of acoustic archives to refining species identifications and advancing our understanding of bat diversity. Our results provide solid acoustic evidence for the occurrence of M. riparius in Belize and El Salvador. However, reliance on bioacoustic data alone to delimit the occurrence of Myotis should be approached with caution. The genus exhibits high diversity, frequent cryptic species, and poorly documented intraspecific variation (Novaes et al. 2023), while comprehensive acoustic verification remains lacking for most Neotrop‑ ical taxa (Zamora‑Gutiérrez et al. 2020). Moreover, the presence of other Myotis species of similar size and with partially overlapping call parameters highlights the risk of misidentification, particularly when records depend solely on unverified acoustic data or on automated classification algorithms without expert valida‑ tion. Therefore, the collection of voucher specimens or genetic samples remains essential for confirming species identity and expanding the reference base needed to refine acoustic diagnostics (Miller et al. 2023; Ochoa et al. 2025). At the same time, the development of open‑access regional call libraries will be critical for documenting geographic variation in echolocation and, together with voucher material, will provide a more comprehensive framework for understanding the evolutionary history of the M. riparius complex in northern Central America. Taken together, these findings reinforce the role of northern Central America as a key region for bat diversity and demonstrate how combining mist‑netting with acoustic monitoring enhances the detection of cryptic or under‑recorded species such as M. riparius. From a conservation perspective, documenting M. riparius in new localities has direct implications for riparian and forested habitats in Guatemala, Belize, and El Salvador, where ongoing pressures from deforestation, agricultural expansion, and watercourse alteration V. threaten populations at the edge of their distribution. Figure 4. Characteristic frequency (Fc) values of five Myotis species from northern Central America, including species of simi‑ lar body size and phylogenetic relatedness to M. riparius. Note the clear separation in the frequency of maximum energy, with interquartile range (50%), median (dark bar),andoutliers. Check List 21 (5) · https://doi.org/10.15560/21.5.930 Trujillo et al. · Myotis riparius in northern Central America 936 ACKNOWLEDGEMENTS We want to thank all field personnel, with special recognition to Alfonzo Pérez. Our appreciation also goes to the Director of the Bocas del Polochic Wildlife Refuge (BPWR), Luis Barrientos, and the Executive Director of Fundación Defensores de la Naturaleza (FDN), Javier Márquez, along with the entire FDN team, for their invaluable support and unwavering dedication to the conservation of Guatemala’s biodiversity and natural heritage. We are also grateful to the Miskito communities of Auka and Tipi, the NGO Forest of the World, and Mopawi for their logistical support during fieldwork in the Honduran Moskitia forest. Finally, we are grateful to the reviewers and editors whose comments and suggestions significantly improved this manuscript. ADDITIONAL INFORMATION Conflict of interest The authors declare that no competing interests exist. Ethical statement No ethical statement is reported. Funding This publication is based upon work partially supported by the United States Agency for International De‑ velopment under award number (Cooperative agreement N. 72052023CA00006). Author contributions Conceptualization: LAT, BM, JGMF. Data curation: LAT, BM, JGMF. Investigation: LAT, BM, DIOM, DS, HAP, NE, DM, KH. WAJ, JGMF. Writing – original draft: LAT. Writing – review and editing: LAT, BM, DIOM, DS, HAP, NE, DM, KH. WAJ, JGMF. Visualization: LAT, BM, JGMF. Author ORCIDs Luis A. Trujillo https://orcid.org/0000‑0001‑8364‑6189 Bruce Miller https://orcid.org/0000‑0001‑5719‑1942 Diego Ordoñez‑Mazier https://orcid.org/0000‑0001‑6285‑662X Diana Salguero https://orcid.org/0000‑0002‑9563‑4668 Hefer Ávila‑Palma https://orcid.org/0000‑0002‑7098‑7635 Nereyda Estrada https://orcid.org/0000‑0002‑0731‑6521 Diana Mansilla https://orcid.org/0009‑0001‑3066‑2641 Katarina Hooper https://orcid.org/0009‑0002‑0170‑6331 José G. Martínez‑Fonseca https://orcid.org/0000‑0002‑3181‑2525 Data availability All data that support the findings of this study are available in the main text. REFERENCES Barquez RM, Sánchez MS, Sandoval ML (2011) Nuevos registros de murciélagos (Chiroptera) en el norte de Argentina. Mastozo‑ ología Neotropical 18: 11–24. Barquez J, Pérez S, Díaz M (2016) Myotis riparius. The IUCN Red List of Threatened Species 2016: e.T14195A22062950. https://doi. org/10.2305/iucn.uk.2016‑1.rlts.t14195a22062950.en. Accessed on: 2025‑01‑29. 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Ecology and Evolution 10 (11): 4928–4943. https://doi.org/10.1002/ ece3.6245 APPENDIX Table A1. Verified records of Myotis riparius in northern Central America, from Guatemala to Nicaragua. Country Department Locality Date Latitude Longitude Source Data type Guatemala Izabal El Estor, Refugio de Vida Silvestre Bocas del Polochic 10.XI.2024 15.3242 −089.3867 New record Museum record Belize Toledo CRFR Expedition Camp 1 19–21.II.1997 16.3817 −089.1208 New record Acoustics Belize Toledo CRFR Expedition Camp 2 18.II.1997 16.3876 −089.0911 New record Acoustics El Salvador Ahuachapán El Imposible National Park 15–18.V.2003 13.8262 −089.9473 New record Acoustics El Salvador Santa Ana Santa Ana Volcano 14–16.V.2003 13.8658 −089.6215 New record Acoustics Honduras Gracias a Dios Auka, Mosquitia Honduras 21–25.VII.2021 14.9402 −083.8323 New record Acoustics Honduras Gracias a Dios Guanaja, East end ‑ Honduras 25–26.VII.2021 16.4885 −085.8290 New record Acoustics Honduras Gracias a Dios Mavita, Rus Rus, Gracias a Dios 9–10.XII.2024 14.7480 −084.4488 New record Acoustics Honduras Cortés Parque Nacional Cusuco, SPS, Cor. 4.V.2021 15.4961 −088.2122 New record Acoustics Honduras Gracias a Dios Prahbani, Mosquitia Honduras 22–24.VII.2021 15.2634 −083.7719 New record Acoustics Honduras Gracias a Dios Tipi, Mosquitia Honduras 25–26.VII.2021 15.2634 −083.7719 New record Acoustics Honduras Intibucá Refugio de Vida Silvestre Mixcure 2.III.2025 14.9402 −088.1712 New record Acoustics Honduras El Paraiso 7 km E Danli, 620 m 14.VIII.1967 14.0333 −086.5182 GBIF.org 2024 https://doi.org/10.15468/dl.s3hytu Museum record Honduras El Paraiso 7 km E Danli, 620 m 14.VIII.1967 14.0333 −086.5182 GBIF.org 2024 https://doi.org/10.15468/dl.s3hytu Museum record Honduras El Paraiso 1 km SE Danli, 780 m 19.VIII.1967 14.0270 −086.5767 GBIF.org 2024 https://doi.org/10.15468/dl.s3hytu Museum record Honduras Olancho 40 km E Catacamas, 500 m 21.IV.1967 14.7997 −085.5263 GBIF.org 2024 https://doi.org/10.15468/dl.s3hytu Museum record Honduras Olancho 40 km E Catacamas, 500 m 19.IV.1967 14.7997 −085.5263 GBIF.org 2024 https://doi.org/10.15468/dl.s3hytu Museum record Honduras Olancho 40 km E Catacamas, 500 m 19.IV.1967 14.7997 −085.5263 GBIF.org 2024 https://doi.org/10.15468/dl.s3hytu Museum record Honduras Olancho 40 km E Catacamas, 500 m 15.IV.1967 14.7997 −085.5263 GBIF.org 2024 https://doi.org/10.15468/dl.s3hytu Museum record Nicaragua Matagalpa Matiguas 17.II.2004 12.7929 −085.4125 Martínez‑Fonseca et al. 2020 Capture Nicaragua Rio San Juan Refugio Bartola 13.XI.2011 10.9725 −084.3375 Martínez‑Fonseca et al. 2020 Capture Nicaragua Rio San Juan Refugio Bartola 14.XI.2011 10.9739 −084.3394 Martínez‑Fonseca et al. 2020 Capture