Гондурасская белая летучая мышь: особенности и эволюция окраски

Species of bat

The Honduran white bat (Ectophylla alba), also called the Caribbean white tent making bat,
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The Honduran white bat was described as a new species, Ectophylla alba, in 1892 by American zoologist Harrison Allen. The holotype that Allen used to describe the new genus and species was collected by Charles Haskins Townsend near the Coco River in Honduras in 1887. It belongs to the leaf nosed bat family, Phyllostomidae. Within Phyllostomidae, it is in the subfamily Stenodermatinae. MacConnell's bat was once included in the genus Ectophylla, but it is now monotypic within Mesophylla.

Like both its common name and specific epithet suggest, the Honduran white bat has bright white fur. The tips of individual hairs are gray, with the grayish coloration more pronounced towards the bat's posterior. This species, along with four Diclidurus species and the ghost bat (Macroderma gigas), is among the only currently known species of bat—more than 1,300 species have been described—where the pelage is all white. Its large nose leaf easily distinguishes it from the northern ghost bat (Diclidurus albus), however, which is the only white bat with which it is sympatric (having an overlapping geographic range). Its wing membranes are black. Its ears, tragi (the cartilaginous projections in front of the ear openings), nose leaf, and lips are a bright, yellowish orange. A 2019 study found that while the brightness of the yellow pigment of the ears did not vary significantly between adults and juveniles, the yellow chroma (colorfulness relative to brightness) of the ears did differ with age. Adult bats had higher yellow chroma in their ears than did juveniles. The yellow of the nose leaf, however, had more variation. Adult males' nose leaves are a brighter yellow than those of adult females; juveniles of each sex did not differ in nose leaf brightness. Adult males also had significantly brighter nose leaves than juvenile males. Similarly to the ears, the yellow chroma of the nose leaf was greater in adults than in juveniles, though not different between the sexes. The authors suggested that the color difference of male and female nose leaves is indicative of sexual dichromatism, meaning that females may select for males with brighter nose leaves. This conclusion was supported by the trend that males with brighter yellow nose leaves tended to have better body conditions. Females could thus use nose leaf color as an honest signal of male fitness when selecting a mate. Another 2019 study found that the distinctive yellow pigment may have been selected for as a result of the bat's tent roosting. Reconstructions of ancestral states showed that the yellow coloration coevolved with tent roosting. As sunlight passes through the green leaves of the tents, it results in a yellowish light; any bats with yellowish coloration would have had more effective camouflage, and thus be more likely to survive, reproduce, and pass on these genes to their offspring. It is a small species, with a head and body length of , a forearm length of , and an ear length of Individuals weigh only .

The Honduran white bat is one of approximately 22 known species of bats that roost within leaf "tents". The Honduran white bat cuts the side veins extending out from the midrib of the large leaves of the Heliconia plant causing them to fold down to form a tent. Tents are likely constructed by multiple individuals; females have been observed constructing tents, but it is likely that males do so as well. New tents are constructed throughout the year, as modifying the leaves into tents causes the leaves to die. Once modified into a tent, a leaf lives approximately 7.5 weeks, compared to 61 weeks in an unmodified leaf. Preferred leaves are long and less than 30 days old. Younger leaves may be preferred because they are easier to bite through and shape than older leaves. It also prefers leaves that are less than above the forest floor. Preferred leaves are in areas of low understory vegetation density, but high canopy vegetation density. Heliconia density is lower surrounding chosen leaves than would be expected if the bats selected leaves randomly. Features such as canopy density may help the tent maintain a consistent microclimate. Tents are usually 23.3 °C (74 °F), with little fluctuation. High canopy density could also protect its tent from disturbance from wind and rain. Because tent construction takes up to several weeks' worth of time from several individuals, choosing more sheltered tents could prolong the life of a tent and protect the bats' investment. Low understory vegetation density is thought to be beneficial by providing an uncluttered airspace for the bats as they exit and enter their tents. Although their tents are typically low to the ground, sunlight filters through the leaf which gives their white fur a greenish cast. This almost completely conceals them if they remain still. Alternately, it has been proposed that its white fur gives it the appearance of a wasp nest, which would be avoided by predators. It likely has several predators, including capuchin monkeys, Central American squirrel monkeys, and snakes. It specializes on a species of fig, Ficus colubrinae.

Little is known about the Honduran white bat's reproductive behaviors. It has been proposed that individuals give birth in April and September, and that estrus occurs post parturition. Pregnant females have been documented in February, March, June, July, and August in Costa Rica, with lactating females documented in March and April. Females have synchronized births, with all births in a colony occurring within the same week. Litter size is one offspring, called a pup. During lactation, mothers will return to their roosts up to six times a night to feed their pups. Its range encompasses a range of elevations from above sea level. It prefers wet evergreen forests and secondary forests, which can accommodate its specific roosting and dietary requirements.