Notopteris, Balionycteris, Pteropus, Eonycteris and Rousettus

Notopteris macdonaldi (Gray 1859) is the long-tailed fruit bat or Fijian blossom bat. This is the most primitive megabat in the LRT and the only one that retains a long tail. It roosts in large cave colonies only on South Pacific islands. Note the mid-dorsal attachment of the proximal wing membranes, rather than a more lateral attachment.

Balionycteris maculatus (originally Cynopterus Thomas 1893; Matschie 1899; 5-6cm in length) is the extant spotted-winged fruit bat, the smallest megabat and the most primitive one in the LRT. It can be readily distinguished from other small species of Pteropodidae by a single pair of lower incisors, 2 pairs of upper molars, and by characteristic pale spots on wing membranes, particularly on digit joints. Like microbats, Balionycteris has short, broad wings and highly maneuverable flight. Balionycteris inhabits small cavities, but rarely cave entrances, and roosts singly, or in small groups.

The Origin of Bats is featured in

Pteropus sp. (Erxleben 1777) ~52mya and extant, ~35 cm in length, is a large fruit-eating megabat. Pettigrew et al. (1989) reported that megabats were sisters to primates while microbats were sisters to insectivores. Phylogenetic analysis was not able to recover those results, but instead found all bats to be sisters to Chriacus. Derived from a sister to Onychonycteris, Pteropus is a living taxon.

Distinct from Onychonycteris, the skull of Pteropus has a deeper, straighter mandible and larger braincase. The mandible has an angled chin. The jugal is more gracile. The canines are larger. Upper P2 is smaller. P3 is larger. P4, M1 and M2 are blunt. M3 is absent. Lower I1 is absent, P3is larger. M1 and M2 are blunt. M3 is a vestige. All the teeth are angled anteriorly and are reduced posteriorly.

The cervicals are longer and more gracile. The posterior dorsal ribs are shorter. The caudals are absent.

All the forelimb elements are longer. The fingers are longer, more gracile and the unguals of digits II-V, if present, are vestiges.

The hind limbs are relatively shorter. The calcar is reduced. The metatarsals are shorter, the toes are longer and the pedal unguals are larger and more highly curved.

Fossil megabats, such as Archaeopteropus transiens (Meschinelli 1903), ~30 mya, Oligocene, had a long tail and long calcar. Schutt and Simmons (1998) reported that Archaeopterus had a calcar more like that of microbats, so considered Archaeopterus a basal microbat. This may not be so because Onychonycteris also had such a calcar.

Rousettus aegyptiacus (Geoffroy 1810, 1812; wingspan 60cm, 15 cm body length) is the extant Egyptian fruit bat. This is the only megabat to use echolocation. It eats large amounts of fruit each night. A claw is present at the terminal phalanx of the first and
second digits; all other fingers have a cartilaginous extremity. Rousettus has one of the highest ratios of brain to body weight among chiropterans, nearly identical to the advanced insectivores, and exceeding the lowest encephalized primates.

Eonycteris spelea (Dobson 1871, up to 11 cm head and body only, tail: 1.8cm) is the extant cave nectar bat, a small sister to Pteropus in the LRT.

Dobson GE 1871. Journal and Proceedings of the Asiatic Society of Bengal 105–106,

Erxleben JCP 1777. Systema regni animalis per classes, ordines, genera, species, varietas, cum synonymia et historia animalium. Classis I, Mammalia, p. 416. Wegand, Leipzig, 636 pp.

Geoffroy Saint-Hilaire E 1810. Description des rousettus et des cephalotes, deux nouveaux genres de la famille des chauvesouris. Annales du Museum d'Histoire Naturelle, Paris 15:86–108.

Geoffroy Saint-Hilaire E 1812. Description des mammiferes qui se trouvent en
Egypte, Description de l'Egypte. II: Mammalia. L'Imprimerie Imperiale, Paris, 752 pp.

Gray GR 1859. The annals and magazine of Natural History, Zoology, Botany and Geology 3. Series IV: 4859.

Holland RA, Waters DA and Rayner JMV 2004. Echolocation signal structure in the megachiropteran bat Rousettus aegyptiacus Geoffroy 1810. Journal of Experimental Biology 207:4361–4369.

Matschie P 1899. Die Fledermäuse der Berliner Museums für Naturkunde. 1. Megachiroptera 72: 80.

Nelson JE and Hamilton-Smith E 1982. Some observations on Notopteris macdonaldi (Chiroptera: Pteropodidae) in Australian Mammal Society 5: 247–252.

Pettigrew JD, Jamieson BGM, Robson SK, Hall LS, McAnally KI and Cooper HM 1989.
Phylogenetic Relations Between Microbats, Megabats and Primates (Mammalia: Chiroptera and Primates. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 325 (1229): 489-559.

Schutt WA and Simmons NB 1998. Morphology and Homology of the Chiropteran Calcar, with Comments on the Phylogenetic Relationships of Archaeopteropus. Journal of Mammalian Evolution 5 (1): 1-32, DOI: 10.1023/A:1020566902992

Thomas O 1893. On some new Bornean mammalia. Ann. Nag. Nat. Hist., S.6 (65):341-347.

wiki/Pteropus
wiki/Archaeopteropus
wiki/Rousettus
wiki/Balionycteris
wiki/Notopteris
wiki/Eonycteris