Chromatic disorders in bats: a review of pigmentation anomalies and the misuse of terms to describe them

Abstract

Chromatic disorders in bats are being reported worldwide at an increasing rate. However, there is widespread misunderstanding and misuse of the associated terminology and concepts in the scientific literature. We conducted an extensive assessment and standardisation of published and unpublished cases of chromatic disorders in bats worldwide. Chromatic disorders have been recorded in at least 609 bats belonging to 115 species and 10 families (after correction of misused terms, 152 cases of albinism, 11 of leucism, 269 of piebaldism, 20 of hypomelanism, three of partial melanism and 94 of melanism; a further 60 records remain unclassified). Of the 354 records in which a location was given, 297 bats were found in closed roost sites, mainly caves, buildings, and mines and galleries, while just three were found roosting externally. This difference could be attributed to the greater monitoring effort employed in underground areas than in forests, and to the greater detectability of bats dwelling in caves and buildings than forest‐dwelling species. Although reports of chromatic disorders in bats are reasonably well spread around the globe, there are large areas from which no disorders have ever been reported: the Central Amazon, almost all of Africa, northern Europe, and almost all of Asia and Oceania. This is likely to be attributable to either the disregard for information on chromatic disorders (e.g. Central Amazon) or to the low abundance of occurring species (e.g. northern Europe). In all, 40% of the records of leucism and piebaldism were misclassified as ‘partial albinism’; leucism was also often used to designate pied aberrations. We propose a standardised classification to distinguish between albinism, leucism, piebaldism, hypomelanism, melanism and partial melanism. Due to frequent confusion, we encourage scientists to follow this classification and we highlight the need to employ comprehensive terminology when describing chromatic disorders in scientific publications.

Collection of voucher specimens for bat research: conservation, ethical implications, reduction, and alternatives

“…When such data were not specified in the text, they were regarded as ‘missing data’ and treated accordingly in the analyses. The reasons for collection were grouped a posteriori into six main categories: 1) museum collection, that is vouchers collected for local or national scientific museums; 2) documentation of aberrant colour (Lucati & López‐Baucells ); 3) taxonomic studies, for example taxonomic revision (species or genus change), species description, or rediscovery of species thought to be extinct; 4) physiological or anatomical studies; 5) disease studies, including epidemiology and active surveillance; and 6) faunal surveys done to compile checklists or establish species’ ranges. For each species, we also recorded the International Union for Conservation of Nature (IUCN) Red List category (; Red List of Threatened Species.…”

First record of albinism for the doglike bat, Peropteryx kappleri Peters, 1867 (Chiroptera, Emballonuridae)

“…are very common in the entrances to caves in the region of Carajás, and have been observed in more than 600 caves. Nonetheless, despite this significant effort, there have been no other reports of albino specimens, which are testimony to the rarity of this condition in this group of animals, as demonstrated by Uieda (2000) and Lucati and López-Baucells (2017), highlighting the importance of these records.…”

“…Such a condition can cause changes in the coloration of specific body parts, such as skin, hair, feathers, scales or the eye, and can even reach extreme cases where there is complete absence of pigmentation throughout the entire body. Changes in body color caused by deficient melanin production can generate several conditions, which (Lucati and López-Baucells 2017) has classified into four types: true albinism, leucism, piebaldism and hypomelanism. All types of melanin production deficiency are hereditary and genetic (congenital) abnormalities.…”

“…al. 2016, Lucati and López-Baucells 2017. Chromatic aberrations that lead to albinism in bats have been reported in 61 species of 10 families (Rhinolophidae, Hipposideridae, Rhinopomatidae, Emballonuridae, Nycteridae, Phyllostomidae, Mormoopidae, Molossidae, Miniopteridae, and Vespertilionidae), in a great number of countries worldwide, but they continue to be a rarely observed event (Uieda 2000, Rosa et al 2017, Nascimento et al 2018, Zortéa and Silva 2018.…”

“…There have been 31 reports of the absence of melanin pigmentation for 17 species of bats in Brazil (Uieda 2000, Rosa et al 2017, Nascimento et al 2018, Zortéa and Silva 2018. Of these records, 20 were cases of albinism (t-inherited, hypopigmentary disorder characterized by a complete lack of melanin caused by the absence of the enzyme tyrosinase; it results in pale skin, white fur or feathers, and red eyes) and 11 case of piebaldism (total lack of melanin in part of the skin and/or hair follicles due to the absence of melanocytes in the affected part) (Lucati and López-Baucells 2017;Rosa et al 2017;Uieda 2000;Zortéa and Silva 2018). This article reports the observations of two albino individuals of Peropteryx kappleri Peters, 1867, which increases the number of individual records of albinism in bats in Brazil to 33.…”