Dr. K. R. Senacha while demonstrating the morphological key characteristics of identifying a Pipistrellus bat species to Volunteer Intern Mr. Arpan Joshi at the Thar Desert in Nakhatrana Tahseel of Gujarat state in India.

Trident Leaf-nosed bat; Asellia tridens 

Global perspective:

The trident bat or trident leaf-nosed bat (Asellia tridens) is a species of bat in the family Hipposideridae. It is widely distributed in the Middle East, South and Central Asia, and North, East, and Central Africa. Its natural habitats are subtropical or tropical dry forests, dry savanna, subtropical or tropical dry shrubland, caves and hot deserts.[2] 

Recently in the year 2013 Asellia tridens was reported for the first time in India from Jaisalmer District of the Thar Desert in Rajasthan State by K. R. Senacha and Sumit Dookia (2013). 

Description:

Individuals weigh 12–13 g (0.42–0.46 oz) and have forearm lengths of approximately 50 mm (2.0 in).[2] 

Taxonomy:

The trident bat was described as a new species in 1813 by French naturalist Étienne Geoffroy Saint-Hilaire. Geoffroy placed it in the genus Rhinolophus, with a scientific name of Rhinolophus tridens.[3] 

Biology and Ecology:

After a gestation length of 10 weeks, females give birth in three weeks at the end of June and the beginning of July. The litter size for each female is one offspring, called a pup. Pups are relatively large at birth, weighing up to 30% of their mothers' weights (2.5–3 g (0.088–0.106 oz)). Though hairless at birth with closed eyes, a sign of altricial offspring, their eyes open by three or four days old, and fur has started growing. For the first two or three days of life, the pup is latched to its mother's pubic nipple at all times. At three or four days old, mothers leave their pups at the roost at night so they can forage. Pups become volant (able to fly) at around three weeks old, and are totally weaned and independent by six or seven weeks old.[2]

Its predators include birds of prey such as the sooty falcon, lanner falcon, barn owl, Pharaoh eagle-owl, spotted eagle-owl, and Long-eared owl.[3]

Conservation Status:

As of 2017, the trident bat is evaluated as a least-concern species by the IUCN. It meets the criteria for this classification due to its wide geographic range; presumably large population size; and the fact that it is not likely to be experiencing rapid population decline. Its range presumably encompasses several protected areas.[1] 

Greater Mouse-tailed bat; Rhinopoma microphyllum 

Global perspective:

The greater mouse-tailed bat (Rhinopoma microphyllum) is a species of bat in the Rhinopomatidae family.[2] 

It is found in Algeria, Bangladesh, Burkina Faso, the Central African Republic, Chad, Djibouti, Egypt, Eritrea, Ethiopia, India, Indonesia, Iran, Israel, Iraq, Jordan, Libya, Mali, Mauritania, Morocco, Myanmar, Niger, Nigeria, Oman, Pakistan, Saudi Arabia, Senegal, Sudan, Thailand, Tunisia, Western Sahara, and Yemen. Its natural habitat is subtropical or tropical dry shrubland. 

Description:

Individuals weigh 12–13 g (0.42–0.46 oz) and have forearm lengths of approximately 50 mm (2.0 in).[2] 

Taxonomy:

The trident bat was described as a new species in 1813 by French naturalist Étienne Geoffroy Saint-Hilaire. Geoffroy placed it in the genus Rhinolophus, with a scientific name of Rhinolophus tridens.[3] 

Biology and Ecology: 

According to a recent research published in Royal Society of London, the greater mouse-tailed bat hibernates at the unusually warm and constant temperature of 68 °F in caves in Israel's Great Rift Valley. From October to February, these bats were discovered semi-conscious, breathing only once every 15–30 minutes, with extremely low energy expenditures.[3]

The species Rhinopoma microphyllum eats exclusively insects.[4] A study on its diet revealed that the species is primarily a Coleoptera feeder in both maternity and summer quarters, although a more diverse feeding habit is found in the summer roosts. Other prey types include Diptera, Neuroptera and Hymenoptera.[5] They mate at the beginning of spring.

Conservation Status:

As of 2017, the trident bat is evaluated as a least-concern species by the IUCN. It meets the criteria for this classification due to its wide geographic range; presumably large population size; and the fact that it is not likely to be experiencing rapid population decline. Its range presumably encompasses several protected areas.[1] 

Lesser Mouse-tailed bat; Rhinopoma hardwickii 

Global perspective:

The Lesser Mouse-tailed bat (Rhinopoma hardwickii) is a species of microbat bat in the Rhinopomatidae family.[2]  Also referred to as Hardwicke's lesser mouse-tailed bat and long-tailed bat, it is named after Major General Thomas Hardwicke (1755–1835), an English soldier and naturalist. It is found in North Africa, some parts of central and eastern Africa, West Asia and east to the Indian subcontinent as described hereunder.[1] 

• Africa : Algeria, Burkina Faso, Chad, Djibouti, Egypt, Eritrea, Ethiopia, Kenya, Libya, Mali, Mauritania, Morocco, Niger, Nigeria, Somalia, Sudan and Tunisia.

• Asia : Afghanistan, Bangladesh, India, Iran, Iraq, Israel, Jordan, Kuwait, Oman, Pakistan, Saudi Arabia, Thailand, and Socotra island of Yemen.

Description:

The lesser mouse-tailed bat is a small bat with a long thin tail resembling that of a mouse, hence its name. It is covered with soft fur on the body, greyish to dark brown in colour, but not on its face, rear abdomen and rump. The lower parts are paler in colour.[2]

The snout of the lesser mouse-tailed bat has a small triangular shaped nose leaf. The large rhomboid-shaped ears have transverse ridges across the pinna and are connected across the forehead with well developed tragi. The uropatagium (flap of skin between the hindlimbs) is small and envelops less than a fourth part of the tail.[2]

The head and body length of the bat ranges from 62 to 71 millimetres (2.4 to 2.8 in) while the tail is 57 to 70 millimetres (2.2 to 2.8 in) long. Other lengths are as follows:[2]

• Forearm: 52.4 to 60 millimetres (2.06 to 2.36 in)

• Hindfoot: 12 to 15 millimetres (0.47 to 0.59 in)

• Ear: 18 to 21 millimetres (0.71 to 0.83 in)

The lesser mouse-tailed bat has a short skull, with a loose tympanic bone and inflated lacrimal region and which is broadest at the squamosal region of the zygomatic arch. It has 28 teeth. The dentition is as follows: 1/2, 1/1, 1/2, 3/3.[2]

Taxonomy:

The trident bat was described as a new species in 1813 by French naturalist Étienne Geoffroy Saint-Hilaire. Geoffroy placed it in the genus Rhinolophus, with a scientific name of Rhinolophus tridens.[3] 

Biology and Ecology: 

The lesser mouse-tailed bat is typically found in arid or semi-arid desert habitat, wherever roosts and adequate food may be found. This includes dry scrub, rocky areas, caves, deserted monuments, abandoned buildings, wells and other underground features. They have been recorded in oases and wadi gorges having Tamarix or Nerium oleander vegetation. In the hot summer months, these bats can be found resting in cracks, nooks and even amongst large rocks.[1]

These bats have been recorded in Algeria and Morocco to occur up to altitudes of 1,100 metres (3,600 ft) above sea level.[1]

Lesser mouse-tailed bats are insectivorous, feeding primarily on beetles, neuropterans and moths, many of which are considered pests by humans.[4] Their diet is less diverse than other bats with beetles comprising up to 50%.[2]

They accumulate fat in a fold of skin in the lower abdomen, which allows them to survive the winter when insect availability is low.[4][5]

Lesser mouse-tailed bats are well adapted to live in hot, dry climates. They have slits or valves just above their nostrils which they can open or close at will, helping to keep the dust out. The bats have physiological control over their kidneys to reduce water loss. During the hot months, these bats move into covered shelters to escape the heat.[4]

Though the bats are active throughout the year, they survive the winter months, when insect availability is low, by remaining in a torpor.[4] Lesser mouse-tailed bats hunt for insects at heights ranging from 5 to 10 meters off the ground,[2] often being mistaken for birds due to their pattern of swooping and gliding.[4]

The bats roost in colonies both small, ranging in size from 4 to 10 individuals, to large, numbering in the thousands. Females tend to group, especially lactating mothers.[2] They hang using both the thumbs and the feet and generally use a shelter for a single day only before moving on.[4]

Male lesser mouse-tailed bats mature at sixteen to seventeen months of age. Female bats become sexually mature at nine months of age and are monestrous i.e. they have one oestrus cycle per year. The mating season is generally in the months of February to April. Gestation lasts from 95 to 100 days and only one offspring is produced in a brood, usually in June–July. The young bats take flight at the age of five to six weeks.[2][4][5] 

Lesser mouse-tailed bats are considered to be a primitive bat in terms of echolocation, primarily due to the reason that these bats produce signals with four or more harmonics with limited frequency variation.[2]

The bats make a variety of sounds, primarily constant frequency (CF) sounds of 48 milliseconds duration, with pronounced second harmonics. The choice of frequency depends upon whether the bat is flying alone, in which case the calls have a frequency of 32.5 kHz, or in a group, when the bats choose one of three frequencies, 30, 32.5 and 35 kHz, so as to avoid jamming each other.[4][6]

While landing or flying around in groups around the roost-site, lesser mouse-tailed bats emit frequency modulated (FM) sounds of 3 ms duration. After landing they produce a multi-harmonic pure tone of 100 ms duration, in which the main frequency predominates.[6]

Conservation Status:

As of 2017, the trident bat is evaluated as a least-concern species by the IUCN. It meets the criteria for this classification due to its wide geographic range; presumably large population size; and the fact that it is not likely to be experiencing rapid population decline. Its range presumably encompasses several protected areas.[1] 

Naked-rumped tomb bat; Taphozous nudiventris 

Global perspective:

The Naked-rumped tomb bat (Taphozous nudiventris) is a species of sac-winged bat in the family Emballonuridae.[2] Found in northern Africa, the Middle East, and southeastern Asia, its natural habitats are dry savanna, subtropical or tropical dry shrubland and forests, caves, and arid areas. 

Description:

The naked-rumped tomb bat is a moderate-sized, sac-winged bat, males typically being slightly larger than females. The head is fairly flat with a long, cone-shaped snout and a shallow depression between the large eyes. The lower lip has a grooved protuberance and the ears are triangular and backward-pointing. There is no nose-leaf and the throat pouches are well-developed in the male but less so in the female. The fur is short and sleek, and covers the whole body apart from the rump, lower belly and hind limbs; there is a sharp division between the furred and naked parts, with about one third of the total surface lacking hair. The dorsal pelage is pale greyish-brown, deep brown or rusty-brown and the ventral pelage is a paler colour than the back. The wing membrane is dark brown and the tail projects freely from the upper surface of the interfemoral membrane.[3] 

Taxonomy:

The trident bat was described as a new species in 1813 by French naturalist Étienne Geoffroy Saint-Hilaire. Geoffroy placed it in the genus Rhinolophus, with a scientific name of Rhinolophus tridens.[3] 

Biology and Ecology: 

According to a recent research published in Royal Society of London, the greater mouse-tailed bat hibernates at the unusually warm and constant temperature of 68 °F in caves in Israel's Great Rift Valley. From October to February, these bats were discovered semi-conscious, breathing only once every 15–30 minutes, with extremely low energy expenditures.[3]

The species Rhinopoma microphyllum eats exclusively insects.[4] A study on its diet revealed that the species is primarily a Coleoptera feeder in both maternity and summer quarters, although a more diverse feeding habit is found in the summer roosts. Other prey types include Diptera, Neuroptera and Hymenoptera.[5] They mate at the beginning of spring.

Conservation Status:

As of 2017, the trident bat is evaluated as a least-concern species by the IUCN. It meets the criteria for this classification due to its wide geographic range; presumably large population size; and the fact that it is not likely to be experiencing rapid population decline. Its range presumably encompasses several protected areas.[1] 

Egyptian tomb bat; Taphozous perforatus

Global perspective:

The Naked-rumped tomb bat (Taphozous nudiventris) is a species of sac-winged bat in the family Emballonuridae.[2] Found in northern Africa, the Middle East, and southeastern Asia, its natural habitats are dry savanna, subtropical or tropical dry shrubland and forests, caves, and arid areas. 

Description:

The naked-rumped tomb bat is a moderate-sized, sac-winged bat, males typically being slightly larger than females. The head is fairly flat with a long, cone-shaped snout and a shallow depression between the large eyes. The lower lip has a grooved protuberance and the ears are triangular and backward-pointing. There is no nose-leaf and the throat pouches are well-developed in the male but less so in the female. The fur is short and sleek, and covers the whole body apart from the rump, lower belly and hind limbs; there is a sharp division between the furred and naked parts, with about one third of the total surface lacking hair. The dorsal pelage is pale greyish-brown, deep brown or rusty-brown and the ventral pelage is a paler colour than the back. The wing membrane is dark brown and the tail projects freely from the upper surface of the interfemoral membrane.[3] 

Taxonomy:

The trident bat was described as a new species in 1813 by French naturalist Étienne Geoffroy Saint-Hilaire. Geoffroy placed it in the genus Rhinolophus, with a scientific name of Rhinolophus tridens.[3] 

Biology and Ecology: 

According to a recent research published in Royal Society of London, the greater mouse-tailed bat hibernates at the unusually warm and constant temperature of 68 °F in caves in Israel's Great Rift Valley. From October to February, these bats were discovered semi-conscious, breathing only once every 15–30 minutes, with extremely low energy expenditures.[3]

The species Rhinopoma microphyllum eats exclusively insects.[4] A study on its diet revealed that the species is primarily a Coleoptera feeder in both maternity and summer quarters, although a more diverse feeding habit is found in the summer roosts. Other prey types include Diptera, Neuroptera and Hymenoptera.[5] They mate at the beginning of spring.

Conservation Status:

As of 2017, the trident bat is evaluated as a least-concern species by the IUCN. It meets the criteria for this classification due to its wide geographic range; presumably large population size; and the fact that it is not likely to be experiencing rapid population decline. Its range presumably encompasses several protected areas.[1]