Chocolate fruit dwarf
| Chocolate fruit dwarf | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Chocolate fruit dwarf ( Enchisthenes hartii ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name of the genus | ||||||||||||
| Enchisthenes | ||||||||||||
| Andersen , 1906 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Enchisthenes hartii | ||||||||||||
| ( Thomas , 1892) |
The velvety fruit-eating bat ( Enchisthenes hartii ) is the only species of the genus Enchisthenes of the subfamily of stenodermatinae the bats .
description
Appearance and dimensions
The chocolate fruit dwarf is tailless and an average of 60 mm long and weighs 17 g. There are no major variations between the different populations, nor is there an obvious gender dimorphism . In general, the chocolate fruit dwarf is very similar to the smaller species of the genus actual fruit vampire , only the structure of the upper inner incisors - they are two-rooted in the chocolate fruit dwarf - and the much stronger expression of the third upper and lower molars are clearly different. The fur of the animals is dark brown on the upper side of the body with a conspicuous white dorsal stripe, going black on the head and shoulders, but noticeably lighter on the underside. The forearms, on average 40 mm long and stretching the flight membrane, are predominantly hairy, the skin between the legs ( interfemoral membrane ) is only 3–4 mm short and very hairy. The skull is 20–22 mm long, with ears 16 mm long. The leaf-like skin formations that surround the nose, typical of fruit vampires, are relatively short and wide, but have a conspicuous, upward-pointing outgrowth, which gave the genus Enchisthenes its name.
behavior
Not much is known about the behavior of the chocolate fruit dwarf; it was mostly observed in the open air, over bodies of water, clearings or above the treetop. The animals often sleep in colonies with numerous other bat species. They eat small fruits - figs, for example, up to 1 cm in size. The figs are picked in flight and eaten hanging from a branch. There are indications that they adapt their whereabouts to the ripening times of certain fruits, for example the animals in Colombia were increasingly sighted during the ripening time of fig trees there.
Reproduction
Little is known about the reproduction of animals either; some authors assume year-round fertility, while there are some local observations that suggest seasonal infertility. Overall, however, there are not enough observations that allow a definite statement on this question.
distribution
The distribution area of the chocolate fruit dwarf ends in the north in the Mexican states of Jalisco and Tamaulipas and extends across Central America to Bolivia and northwestern Peru , on both sides of the main Andean ridge in the south and Trinidad in the east. It is not clear whether the species occurs continuously in this area or in individual, widely isolated populations, but the lack of sightings in Nicaragua and Northern Colombia suggests the latter; Overall, with the exception of a few regions in South America, the chocolate fruit dwarf is considered rare to very rare.
The chocolate fruit dwarf occurs at altitudes from sea level to altitudes over 3000 m; with the exception of Mexico, where it occurs predominantly at altitudes up to 1000 m, the emphasis is on moderate to higher altitudes. It occurs in various forest forms, in central Mexico mostly in cloud forests or in temperate subtropical dry forests such as the oak-pine mixed forest. Further south, the habitat of the chocolate fruit dwarf is more closely associated with moist forests, such as rain and cloud forests, but it is also found less often in drier areas.
Predators and parasites
The only proven predators are owls , in Ecuador owl bulbs with up to 20 skulls of the species have been found. In contrast, at least nine species of bat flies of the Streblidae family and mites of the Taxa Labidocarpidae , Spinturnicidae and Trombiculidae were detected as ectoparasites .
Danger
The chocolate fruit dwarf is classified as not endangered by the IUCN , but the Mexican federal government considers it necessary to protect the species in Mexico.
Systematics
The classification of the chocolate fruit dwarf in the biological systematics in its own genus or in the genus Artibeus or Dermanura changed several times in the past, predominantly today it is classified in its own genus. When it was first described, it was placed in the genus Artibeus , but in 1906 Anderson put it in its own genus for the first time because of the dentition that differs from the known Artibeus species - in particular the structure of the incisal edge of the inner lower incisors. In a later division of the taxon Artibeus, the chocolate fruit dwarf was assigned to the taxon Dermanura ( Dermanura is partly classified as a subgenus of Artibeus , partly as a sister genus to Artibeus ). Contrary to the older morphological findings, however, genetic investigations of the relationships between the chocolate fruit dwarf and the Taxa Artibeus or Dermanura could not be confirmed and consequently its classification as a separate genus prevailed again. This was confirmed in a genetic test in 2016. Accordingly, the genus is basal within the tribe Stenodermatini with all other species (the genera Chiroderma , Uroderma , Ectophylla , Artibeus , Stenoderma ) as a sister group .
Surname
The generic name Enchisthenes means armed with a spear and refers to a conspicuous upward and downward part of the leaf-like skin formations that surround the nose. The specific epithet Hartii is named in honor of the director of the Botanical Garden in Trinidad JH Hart, who sent the later holotype to the British Museum . Because of the classification of the chocolate fruit dwarf by some authors into the taxa actual fruit vampires or Dermanura, the species is sometimes scientifically referred to as Artibeus hartii or Dermanura hartii .
The exact origin of the unusual German name “Schokoladen-Fruchtzwerg” is not clear.
Individual evidence
- ↑ a b c d e f g h i j Joaquin Arroyo-Cabrales, Robert D. Owen: Enchisthenes hartii. (PDF; 500 kB) In: Mammalian Species No. 546. American Society of Mammalogists, May 9, 1997, pp. 1-4 , archived from the original November 4, 2014 ; Retrieved November 5, 2009 .
- ↑ a b c d e Ronald M. Nowak: Walker's Mammals of the World . 6th edition. The Johns Hopkins University Press, Baltimore / London 1999, ISBN 0-8018-5789-9 , Volume 2, pp. 395 ff.
- ↑ a b Carmen L. Orozco-Lugo et al .: Velvety Fruit-Eating Bat (Enchisthenes hartii; Phyllostonidae) in Morelos, Mexico . In: The Southwestern Naturalist 53 (2008), Southwestern Association of Naturalists, pp. 517 ff.
- ^ Suely A. Marques-Aguiar: Genus Enchisthenes . In: Alfred L. Gardner (Her.): Mammals of South America, Volume 1: Marsupials, Xenarthrans, Shrews, and Bats , University of Chicago Press, Chicago 2008, ISBN 978-0-226-28240-4 , p. 326 ff.
- ↑ Enchisthenes hartii in the IUCN Red List of Threatened Species . Listed by: Bear Specialist Group, 2008. Retrieved November 5, 2009.
- ↑ Robert J. Baker, Sergio Solari, Andrea Cirranello, Nancy S. Simmons (2016): Higher level classification of phyllostomid bats with a summary of DNA synapomorphies. Acta Chiropterologica 18 (1): 1-38. doi: 10.3161 / 15081109ACC2016.18.1.001
- ^ Murray Wrobel: Elsevier's dictionary of mammals: in Latin, English, German, French and Italian , 2007, ISBN 0-444-51877-0 , p. 33
Web links
- First picture on flaus-online.de
- Joaquin Arroyo-Cabrales, Robert D. Owen: Enchisthenes hartii. (PDF; 500 kB) In: Mammalian Species No. 546. American Society of Mammalogists, May 9, 1997, pp. 1-4 , accessed November 5, 2009 .