Subclass Eutheria

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Subclass Eutheria Order Insectivora

• Thought to represent what early eutherians looked
  like
• Probably a monophyletic group ? still debatable
• Taxonomy ? 6 families with 400 extant species
• Family Solenodontidae (Solenodons)
• Family Tenrecidae (Tenrecs and otter shrews) ? 10
  genera, 24 species
• Family Chrysochloridae (Golden mole)
• Family Erinaceidae (Hedgehogs and gymnures)
• Family Talpidae (Moles and desmans)
• Family Soricidae (Shrews)
• Distribution of order ? All faunal regions except
  Australian

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Order Insectivora General morphology

• No representative characteristics to distinguish
  them ? One of the most anatomically diverse
  orders
• No auditory bullae in some members
• Tympanic cavity is often partially covered by
  processes or other bones
• Cerebrum smooth
• Jugal bone reduced or absent in most ? zygomatic
  arch incomplete
• Enlargement of incisors and reduction of canines
• Many species have primitive eutherian dental
  formula
• Reproduction
• Testes usually abdominal or within inguinal canal
• If external, anterior to penis
• Cloaca is present in some insectivores

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Soricidae (shrews)

• Distribution worldwide except Australia
• 23 genera, 312 species 6.7 of extant mammals
• Among the smallest mammals ? 2.5 g to 180 g
• No zygomatic arch or tympanic bulla
• Single lower incisor ? large and procumbent
• (projects forward)
• Eyes small pinnae visible
• Nocturnal and insectivorous
• One of three groups of mammals that are
• venomous
• 1) Monotremes
• 2) Solenodons
• Incredibly high metabolism
• Rudimentary form of echolocation (similar to
• solenodons)

Common shrew (Sorex araneus)
Bairds shrew (Sorex bairdii)
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Idaho mammals Soricidae

• Six species
• Water shrew (Sorex palustris)
• Vagrant shrew (Sorex vagrans)
• Dusky shrew (Sorex monticolus)
• Pygmy shrew (Sorex hoyi)
• Masked shrew (Sorex cinereus)
• Merriams shrew (Sorex merriami)

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Idaho mammals Soricidae
Water shrew (Sorex palustris)
Vagrant shrew (Sorex vagrans)
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Idaho mammals Soricidae
Pygmy shrew (Sorex hoyi)
Masked shrew (Sorex cinereus)
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Idaho mammals Soricidae
Dusky shrew (Sorex monticolus)
Merriams shrew (Sorex merriami)
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Talpidae (moles and desmans)

• Distribution Holarctic
• 17 genera, 42 species
• Fossorial insectivores
• Build a network of tunnels
• Zygomatic arch complete ? unlike other
• insectivores
• Eyes small and often lie beneath skin
• Snout long and slender ? contains
• touch receptors
• Ears usually lack pinnae
• Body fusiform
• Forelimb modifications
• 1) Digits point to the side
• 2) Palm faces backward
• 3) Elbows point upward

Star-nosed mole (Condylura cristata)
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Idaho mammals Talpidae

• Fur is black and velvet-like
• Small size ? 147-175 mm (6 to 7 in.)
• Live in agriicultural areas as well as coastal
  dunes,
• grassy meadows, coniferous and deciduous forests
• and woodlands, and along streams
• Active throughout year
• Solitary ? one ind. per burrow system
• Average life span is 4 to 5 years

Coast mole (Scapanus orarius)
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Chrysochloridae (Golden moles)

• Distribution S. Africa in a variety of habitats
• 7 genera, 18 species
• Resemble true moles
• Phylogenetic affinities are in question
• Fossorial life style
• Pelage color varies but generally has
• a metallic hue to it.

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Solenodontidae

• Distribution Restricted to Haiti and Cuba
• 1 genus and 2 species
• Resembles a large shrew with a long snout
• Lower incisor has a groove ? carries toxin
• Generalized omnivores
• Nocturnal
• Produces clicks ? crude form of echolocation?
• Critically endangered

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Erinaceidae (hedge hogs and gymnures)

• Distribution Africa, Eurasia, SE Asia and Borneo
  
• 7 genera, 21 species
• Eyes and pinnae moderately large
• Nocturnal and terrestrial
• Omnivorous
• Probably heterothermic
• Gymnures (moon rats) restricted to SE Asia

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Tenrecidae

• Distribution Madagascar and Central and Western
  Africa
• 10 genera, 24 species
• Vary widely in size and morphology
• Loosely resemble hedgehogs
• Others look like shrews
• One unique subfamily resembles otters ? otter
  shrews
• Most are nocturnal and omnivorous

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Tenrecidae Otter-shrew
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Order Dermoptera Cynocephalidae

• Name means skin-winged
• Gliding means of locomotion ? glissant
• Membrane extending from neck to forepaws to
• hind feet and to tail
• Large eyes and face resemble fruit bats or lemurs
• Taxonomic history confusing
• Taxonomy ? 1 family, 1 genus, 2 species
• Distribution Oriental faunal region
• Cynocephalus volans ? Phillipines
• C. variagatus ? Indochina, Malaya,
• Sumatra, Java, Borneo, and small islands
• Arboreal and crepuscular
• Diet flowers, fruits, and leaves
• Den in nest cavities in trees

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Order Dermoptera Cynocephalidae
Cynocephalus variegatus
Cynocephalus volans