We do not have specimens of the following bat families:

Rhinopomatidae

Rhinolophidae

Mormoopidae

Noctilionidae

These will be covered primarily in lecture, but you should be familiar enough

with them that if I refer to them in the context of a question on a lab exam,

you can recognize who they are, e.g., “Contrast ways in which molossid and

mormoopid bats fly as compared with most bats.”

Order Chiroptera

Suborder Megachiroptera

Family Pteropodidae – flying “foxes”

These large fruit bats are inhabitants of the Old World tropics. They hang

from trees during the day and travel many miles during their nightly foraging.

Note the exceptionally large, curved claws – why are they so narrow? Can

you pick out characteristics, skeletal and otherwise, that are typical of ptero-

podids? In what ways do they differ from the microchiropterans?

Be sure to thumb through the bat book to see some illustrations of many of

the bats we’ve talked about in lecture.

Order Chiroptera

Suborder Microchiroptera

Family Phyllostomidae

This is the most diverse family of bats in terms of feeding habits, producing the

largest number of genera among bats. All share in common the fact that their

hindfeet are permanently rotated 180^o, so they can’t place the plantar surface of

the hindfoot down. They all have relatively broad wings (low aspect ratio) and

mostly use short, slow flights while foraging. The following cards show examples

from most of the subfamilies:

Phyllostominae Carollinae Desmodontinae

Glossophaginae Sturnirinae

Phyllonycterinae Stenoderminae

See also Walker’s Mammals of the World to get a feeling for the diversity of

this and other families of bats.

Family Phyllostomidae

Subfamily Phyllostominae

Here are examples of the most primitive subfamily. Note in the two write-ups,

the typically tuberculosectorial teeth of these insectivorous bats. The stuffed

specimen shows the well-developed nose leaf, large pinnae and tragus typical of

these bats. The National Geographic shows one of the most unusual feeding

habits developed by any bat – wouldn’t you know it would be a phyllostomid!

Family Phyllostomidae

Subfamily Glossophaginae

Note the exceptional elongation of the rostrum in these highly nectarivorous

bats. What other features reflect their nectar-feeding habits? See pictures in

Walker’s Mammals of the World (around p. 291...).

Family Phyllostomidae

Subfamily Sturnirinae

These guys (such as the specimen pictured on this book cover) feed on

moderately hard fruit. Compare the skull and tooth features with the

Stenoderminae (next station). What features differ? Why?

Family Phyllostomidae

Subfamily Stenoderminae

Compare the skull and tooth characteristics of these frugivores with the

Sturnirinae (previous station). What do they tell you about the kinds of

fruit the two subfamilies are eating? Why do you think these kinds of

differences evolved? Why is this niche partitioning most common in the

tropics?

Family Phyllostomidae

Subfamily Desmodontinae

This used to be a family of its own, but recently has been placed as a

subfamily within the Phyllostomidae. Not only do vampire bats not occur

in Transylvania (central Europe), but they are not the big size depicted so often

in Dracula movies. These tiny bats (3-4” in body length) live only in the New

World from subtropical regions of Mexico south through Central America and into

the tropics of So. America. They are the only mammals who live entirely on blood.

The 2 upper incisors angle forward and are extremely sharp. The upper and lower

canines are large and blade-like. With these, the bats nick the skin of a sleeping

prey. As they lick the wound, an enzyme in their saliva (desmokinase) acts as

an anticoagulant so that the blood flows freely. The postcanine teeth are greatly

reduced or absent (depending on species). The face lacks strong ornamentation

and the tragus is small, reflecting their relatively poor echolocation abilities as

compared with insectivores. What do you expect their flying habits to be like?

What other features do you expect to find that relate to their unique habits?

See blue book, p. 84-85.

Family Molossidae

Free-tailed bats are common in North America, especially in the

Southwest. A large part of their tails is free of the uropatagium,

giving them their common name. They parallel the habits of the

Mormoopid pats in being swift flying little critters that catch flying

insects on-the-wing. Can you identify the important features of the

skeleton and related muscles that allow these bats to be such good

flyers? In what ways are they similar to Mormoopids?

HANDLE GENTLY!

Family Vespertilionidae

By far the most successful family of bats in the world, the Vespertilionidae

are also the most common bats in North America. Though most eat insects,

they pursue their insectivorous habits in a variety of ways: some pounce

on large bugs and return to their roosts to eat them. A few SW forms even

attack scorpions. But most, like the specimens we have out today, catch

insects on-the-wing. All of us have seen this behavior as we look up at the

darkening sky on a summer night and see the small bats weaving back and

forth as they catch small airborne insects. Their mouths are used as nets to

filter the small prey from the dense clouds that occur over rivers, etc.

Family Vespertilionidae

Pipistrellus is one of the smallest of the eastern bats. They are not powerful

fliers and may be caught with an insect net. They are highly social and live in

huge colonies. They are one of the few bats that remain in the northern latitudes

throughout the year.

Lasiurus, the hairy-tailed bats, are very strong fliers. They migrate between the

US and Canada. L. borealis is the Red bat, very common around here. L. intermedius

is the No. Yellow bat – not common here but found from So. Carolina to Florida

and the Gulf Coast, preferring to roost among the Spanish moss of the warmer climes.

Family Vespertilionidae

Myotis forms the genus referred to as “little brown bats”, for obvious reasons!

This is the most widespread genus of all mammals. Note the lack of facial

ornamentation except for the tragus.

This skull of a Hoary bat (Lasiurus cinereus) demonstrates the typical

tuberculosectorial teeth of insectivorous bats.

Note the widely separated premaxillae. This is typical of most microchiropteran

bats and may relate to both echolocation and to insect feeding. Or it may just

be a weird bat feature! How would you try to determine which is true?

Order Xenarthra (old Order Edentata gives them a common name – edentates)

Please puruse pp. 62-63, 68-69, 70-71 and 72-73 for glimpses

of the variety among the edentates.

Family Bradypodidae – tree sloths

The short globular face is typical of leaf eaters like these tree sloths.

Teeth are simple and peg-like (see the armadillo). What adaptations

are associated with a totally arboreal life? How do they disperse?

Family Myrmecophagidae – true anteaters

Anteaters are the only totally toothless edentates. Other adaptations for

anteating include the long, slender, tube-like skull; reduced zygomatic arch,

and modified tongue. What adaptations would you expect to find

postcranially?

Family Dasypodidae – armadillos

Armadillos are the only edentates that are still extending their range

northward following the reunion of North and South America about

2 million years ago. They are thought to be living remnants of the

ancient dasypodids that gave rise to all the other Xenarthran edentates.

The nine-banded armadillo is the common form in the US. Note that

the nine bands are formed from accordion-like segments allowing

flexibility in movement of the shell. What is the shell made of? Note

the typically simple edentate teeth. What skeletal features are typical

of xenarthrans?

Thumb through the Xenarthra (Edentate), p. 42-55.

There is also a really good section on bats (pp. 58-89). Many of the

specimens we have talked about are shown here.

As you look through the section on Chiroptera (pp. 169-351 – I told you

it was a big order!), can you recognize the groups we’ve discussed? Can

you infer their lifestyles from appearance and tooth characteristics?