Vampire moths: a lifetime of night observations reveals how Calyptra drinks blood

Some moths do more than sip nectar. Among the roughly 17 currently recognized species of the genus Calyptra (Erebidae) in Asia, eight are known to pierce the skin of mammals, including humans, with a specialized proboscis and drink fresh blood. A newly published book by Swiss entomologist Hans Bänziger, who has lived in Thailand and studied these insects in the wild since 1967, now summarizes decades of fieldwork on their behaviour, ecology and taxonomy.

The 232-page hardbound volume, published by Natural History Publications (Borneo) in Kota Kinabalu, Malaysia, is largely built on the author’s own observations across 545 nights in Papua New Guinea, West Malaysia, Thailand, Laos, Sri Lanka, India and Nepal. It is richly illustrated with 263 colour photographs, one black-and-white photo and 114 black-and-white drawings and diagrams, many of the images captured with analogue cameras, in some cases more than 30 years ago.

The book opens with three chapters describing how the author came to work in the region, his wide-ranging entomological activities and his field methods, interspersed with anecdotes. Bänziger, described in the publisher’s review as a field entomologist who spent countless hours alone at night watching tear-sucking and fruit-piercing moths, also studied caterpillars, tear-drinking bees and the pollinators of Paphiopedilum slipper orchids and flowers of Aristolochia, Rafflesia and Rhizanthes.

A substantial taxonomic section treats Calyptra and its close relatives, including an identification key to all species and subspecies, one lectotype designation, one generic synonymy and the reinstatement of two subspecies. Four tables supply additional morphological characters and measurements, and each taxon is presented in detail with lists of examined specimens, illustrations of male genitalia, photographs of adults and larvae, notes on their inconspicuous and often scarce food plants, and information on seasonality and habitat preferences.

The largest part of the book documents how and on what these moths feed, based on observations in the wild and in local zoos and enclosures for domestic animals. The specialized mechanism of skin-piercing by the modified proboscis is explained and illustrated, along with the proposed evolutionary pathway from fruit-piercing and sap-sucking to skin-piercing and blood-drinking. In every case where a human was the victim, that human was the author himself.

One of the book’s surprising findings concerns sex differences: only male Calyptra moths feed on blood, and, as the review notes, not for the reason that might seem most likely. Another notable argument concerns Calyptra thalictri, the only species of the genus occurring in Europe. The book presents the case that this species is not naturally haematophagous, although it may draw mammal blood under constrained conditions.

The volume closes with a topic that places these so-called vampire moths in a current spotlight: the potential transmission of pathogens. According to the review, such transmission is considered unlikely and remains unproven, so the book treats the question as an open one rather than a demonstrated risk.

Written in English and priced at 50 US dollars from the author or 250 Malaysian ringgit from the publisher, the book is recommended for lepidopterists and for entomologists, biologists, ecologists, veterinarians and medical doctors interested in exotic species and unusual animal behaviour. For anyone curious about how a lineage of moths moved from piercing fruit to piercing skin, it offers a rare, decades-deep record of direct field observation.

Subject of Research: Behaviour, ecology and taxonomy of the blood-sucking moth genus Calyptra

Article Title: Bänziger H (2021) Vampire moths. Behaviour, ecology and taxonomy of blood-sucking Calyptra .

Article References: Schwendinger, P. J., & Landry, B. (2021). Bänziger H (2021) Vampire moths. Behaviour, ecology and taxonomy of blood-sucking Calyptra.. Alpine Entomology, 5, 115-116. https://doi.org/10.3897/alpento.5.76016

Image Credits: AI Generated

DOI: 10.3897/alpento.5.76016

Keywords: Calyptra, vampire moths, Lepidoptera, Erebidae, haematophagy, proboscis, taxonomy, field entomology, Southeast Asia, book review, pathogen transmission, Calyptra thalictri