Remarkable Bat Discoveries from the ZooKeys Archives

These discoveries, ranging from a species rediscovered after a century to new regional records, emphasise the impressive diversity of bats.

Bats are nocturnal mammals that are critical to healthy ecosystems around the globe; they act as pollinators, seed dispersers, and natural pest controllers. In honour of Bat Appreciation Day (17 April), we are highlighting some of the most interesting bats published in our open-access journal ZooKeys.

The following discoveries, ranging from a species rediscovered after a century to new regional records, emphasise the remarkable diversity of bats and the ongoing efforts of researchers to understand and protect them.

The Strange Big-eared Brown Bat (Histiotus alienus)

Adult male of Histiotus alienus, captured on the municipality of Palmas, Paraná state, Brazil. (Image credit: Cláudio et al.).

For over a hundred years, the strange big-eared brown bat was known only from a single specimen collected in Uruguay in 1916. This elusive species remained unseen by the scientific community for a century, leading to significant uncertainty regarding its biology and true distribution.

However, a study led by Brazilian researchers documents the rediscovery of this bat in the Palmas Grasslands of southern Brazil, providing the first confirmed record for the country. This finding significantly expands the known range of the species and offers researchers the first opportunity to provide a detailed redescription.

Histiotus alienus is distinguished by its large and oval ears that are connected by a low skin fold. Its fur is a deep, dark brown on the back, while the underside is slightly paler. The rediscovery occurred in a unique landscape characterised by high-altitude grasslands and Araucaria forests, a habitat that is increasingly threatened by human activity.

Learn more: Cláudio VC, Almeida B, Novaes RLM, Navarro MA, Tiepolo LM, Moratelli R (2023) Rediscovery of Histiotus alienus Thomas, 1916 a century after its description (Chiroptera, Vespertilionidae): distribution extension and redescription. ZooKeys 1174: 273-287. https://doi.org/10.3897/zookeys.1174.108553

The Flat-skulled Woolly Bat (Kerivoula depressa)

Kerivoula depressa. (Image credit: Liang et al.).

The world of bat taxonomy is constantly shifting as researchers use new tools to differentiate species that look nearly identical. Another study formally documents the first records of the flat-skulled woolly bat, Kerivoula depressa, in China.

Previously, many woolly bats in the region were grouped together under other names, but detailed morphological and genetic analysis confirmed that K. depressa is a distinct part of the Chinese fauna, specifically in Guangdong and Yunnan provinces.

The defining feature of this species is its notably flattened braincase. This physical trait is an evolutionary adaptation that allows the bat to roost in very narrow spaces, such as the hollow internodes of bamboo. The bat has woolly fur that ranges from buff brown to dark brown, and it is relatively small in size.

The presence of this specialist bat in China highlights the complexity of tropical forest ecosystems and the need for further taxonomic work to correctly identify and conserve local biodiversity.

Learn more: Liang X, Xie H, Li Y, Huang Z, Li S, Wu Y, Yu W (2023) First record of the flat-skulled woolly bat Kerivoula depressa and the Indochinese woolly bat K. dongduongana (Chiroptera, Vespertilionidae) in China. ZooKeys 1149: 1-15. https://doi.org/10.3897/zookeys.1149.85821

The Lesser False Vampire Bat (Megaderma spasma)

Megaderma spasma. (Image credit: Cook-Price et al.).

Islands often host a high number of unique species, yet their mammalian populations are frequently understudied. A comprehensive survey on Ko Pha-ngan, an island off the coast of Thailand, identifies the lesser false vampire bat, Megaderma spasma, as a new record for the island.

This species is a member of a group known for their distinctive appearance and predatory habits. While its name might sound ominous, it does not feed on blood; instead, it preys on insects and occasionally small vertebrates.

The lesser false vampire bat is easily recognised by its exceptionally large ears that are joined at the base and the absence of a visible external tail. During the survey, researchers found this species in a variety of environments, including national park forests, disturbed forest fragments, and areas with human settlements.

The discovery of M. spasma and eighteen other new records on Ko Pha-ngan demonstrates the importance of conducting biodiversity surveys in tourist-heavy regions to inform better conservation policies.

Learn more: Cook-Price DR, Petko ON, Makchai S, Artchawakom T, Suwanwaree P (2025) Mammal diversity survey of Ko Pha-ngan in Surat Thani Province, Thailand. ZooKeys 1229: 77-102. https://doi.org/10.3897/zookeys.1229.118127

The Grey-bellied Dwarf Dog-faced Bat (Molossops griseiventer)

Details specimen of Molossops temminckii. (Image credit: Ramírez-Chaves et al.).

Some species remain hidden until scientists take a closer look at existing museum collections and genetic data. For years, the grey-bellied dwarf dog-faced bat was considered a synonym of the more common Molossops temminckii. However, a recent revision has revalidated Molossops griseiventer as a separate species.

This grey-bellied dwarf dog-faced bat can be identified by its characteristic greyish ventral fur and specific cranial proportions. Beyond its appearance, the revalidation of this species has major implications for its protection. Unlike its more widespread relatives, M. griseiventer is restricted to the inter-Andean valleys of Colombia, a region heavily impacted by agricultural development.

Because it is now recognised as an endangered species, conservationists can advocate for specific protections for its remaining habitat. This case proves that understanding the true diversity of bats is a prerequisite for effective conservation.

Learn more: Ramírez-Chaves HE, Morales-Martínez DM, Martínez-Medina D, Ossa-López PA, Rivera-Páez FA (2023) Revising the diversity within the Dwarf Dog-faced Bat, Molossops temminckii (Chiroptera, Molossidae), with the revalidation of the endangered Molossops griseiventer. ZooKeys 1180: 237-256. https://doi.org/10.3897/zookeys.1180.109091

The stories of these four species remind us that our understanding of biodiversity is always evolving. Through continued exploration and open-access publishing, we can better appreciate and protect the bats that share our planet.

Once again, Happy Bat Appreciation Day from ZooKeys and Pensoft Publishers!

For more articles on zoology, visit the ZooKeys website and follow the journal on BlueSky and Facebook.

Guest Blog Post: New Area of Importance for Bat Conservation in Honduras

The recognition of the “Ceguaca, la Mujer de los Juncos” locality comes as a result of research work – published last year in Subterranean Biology – which produced the first checklist of bats for Santa Bárbara


Guest blog post by Eduardo Javier Ordoñez-Trejo and Manfredo Alejandro Turcios-Casco


Bat populations are threatened due to fragmentation and loss of their habitats. Meanwhile, dry forests are some of the least studied and most threatened ecosystems in Honduras, and similarly, so have been the caves.

We had to walk at least two hours to reach either of the caves in El Peñon or Quita Sueño, so we would take our full equipment: for camping, cooking and studying bats.
Photo by Hefer Ávila

Caves are important reservoirs of species, as they offer perks no other habitat can provide at once: a refuge from predators, inconstant weather, and a critical venue for social interactions, reproduction, hibernation, roosting and nutrients. In order to protect bat populations, the Latin American and Caribbean Web for Bat Conservation (RELCOM) supports the establishment of Areas of Importance for the Conservation of Bats, abbreviated as AICOMS (Spanish for Areas with Importance for the Conservation of Bats) .

It was at least a two-hour walk between the caves of Monte Grueso and the caves of El Peñon. The final stint, though, included a swim across Rio Ulúa, one of most extensive rivers in Honduras.
Photo by Hefer Ávila

Together with biologists of the National Autonomous University of Honduras (UNAH) and local community members, we provided the first ever checklist of bat species in the Dry Forest of Ceguaca, Santa Barbara (Honduras), and described the importance of two caves in the area for bat conservation based on species richness. We published this study last June in Subterranean Biology.

The study is openly accessible in Subterranean Biology

We found that caves in Ceguaca are inhabited by at least 23 bat species of four families, which represents approximately a fifth of all species known from Honduras. Their inhabitants include several threatened species like the hairy-legged vampire bat (Diphylla ecaudata), one of the three existing vampire bats, and rare species with few official records in the area, such as Schmidts’s big-eared bat (Micronycteris schmidtorum). These caves may also represent a critical site for roosting and nursing. During our study, we managed to record pregnant and lactating females of several species, as well as reproductive males.

The certificate issued by RELCOM recognising the caves in Ceguaca as an Area of Importance for the Conservation of Bats, dated 6th March 2020

“It feels wonderful to see that our work has had great results and that with our efforts, we established an area where bats will be protected and studied. This certification also includes the name of Roberto Castellano, an elder member of the community of Ceguaca, who helped us during the fieldwork as our guide. He was a great conservationist of this area and protector of the caves. Unfortunately, he passed away during the study, however, due to his enormous contribution, we dedicated our article to him and included him as part of this AICOM success.”

José Alejandro Soler Orellana, co-author of the study.

Using what we learned in Ceguaca’s caves, we approached the Program for Bat Conservation of Honduras (PCMH) and showed them the evidence the locality was indeed a precious place with a spectacular bat diversity. Consequently, thanks to our collaboration with the PCMH, the site was effectively declared as an Area of Importance for the Conservation of Bats by RELCOM on 6th March 2020. 

This is an enormous step for bat conservation in the country. Bat conservation efforts should focus on studying and protecting these and other important habitats. We also need to make sure that local people appreciate the important role the bats play in the ecosystem.

A close up of a spider

Description automatically generated
We captured this adult Pallas’s long-tongued bat (Glossophaga soricina) female in a cave in Monte Grueso. She must have been returning to the cave after spending the day pollinating local plants. During these surveys, we found trees with opened flowers of Mexican calabash (Crescentia alata).
Photo by Hefer Ávila

***

Research article:

Turcios-Casco MA, Mazier DIO, Orellana JAS, Ávila-Palma HD, Trejo EJO (2019) Two caves in western Honduras are important for bat conservation: first checklist of bats in Santa Bárbara. Subterranean Biology 30: 41–55. https://doi.org/10.3897/subtbiol.30.35420