Insectivora: Soricomorpha

Solenodonts, Tenrecs & Moles

Taxa on This Page

1. Solenodontidae
2. Soricomorpha
3. Talpoidea
4. Tenrecoidea

Descriptions

Soricomorpha: Otlestes?

Range: originally tentatively considered from the Late Cretaceous?, now from the Early Paleocene

Phylogeny: Insectivora::: Erinaceomorpha + *: Tenrecoidea + (Solenodontidae + (Talpoidea + Soricoidea))

Characters: head small [A+02$]; alisphenoid canal elongate & continuous anteriorly with exit foramina of ophthalmic or facial divisions of Vth nerve [A+02$]; dentary with angular process at posteroventral corner narrow & without taper [A+02$]; P4 parastyle on mesiobuccal margin projects mesially at a sharp angle [A+02$]; M1 parastyle on mesiobuccal margin projects mesially at a sharp angle [A+02$].

Links: Soricomorpha Mikko's Phylogeny); Eurasian Insectivores and Tree Shrews - Status Survey and ... taxonomic history); Molecular evidence for multiple origins of Insectivora and for a ... molecular maundering); Untitled more sensible approach); Mammalian mitogenomic relationships and the root of the eutherian ... no comment); Mitogenomic analyses of eutherian relationships ditto); pal2 (list of Paleocene species).

References: Asher et al. 2002) [A+02]. ATW030727.

Tenrecoidea: tenrecs)  Echinops, Geogale, Hemicentetes, Limnogale, Microgale, Micropotamogale, Oryzorictes, Potamogale, Tenrec.

Range: from the Eocene of North America and Miocene of Africa [N99]. Currently Madagascar and parts of West Africa [N99].

Phylogeny: Soricomorpha:: (Solenodontidae + (Talpoidea + Soricoidea))  + *.

Characters: shrew to rabbit size (4-40 cm) [N99] [V+00]; snout usually long & slender [V+00]; maxilla with long posterior process extending past tooth row along ectopterygoid margin [A+02$]; maxilla not ventrally convex along tooth row [A+02$]; nasals long & narrow [N99]; lacrimal foramen small [A+02$]; orbits small [V+00]; jugal absent [V+00]; pinnae conspicuous [V+00]; tympanic annular [V+00]; tympanic roof lacks vidian foramen for vidian branch of carotid [A+02$]; squamosal roofs much of tympanic cavity [V+00]; basisphenoid with tympanic process contributing to anterior wall of bulla [A+02$]; stapedial artery passes through foramen in alisphenoid contribution to anterior wall of middle ear [A+02$]; cerebrum smooth [M+00]; braincase not constricted between orbits [N99]; mesial dentition quite variable [V+00]; P1 always absent [N99] [V+00]; P3 mesiodistally longer than P2 [A+02$]; p3 prominent cusp on mesial margin [A+02$]; molars 2-4/2-3 [V+00];  upper molars tricuspid & triangular (zalambdodonty), but W-shaped ectoloph dilambdodonty) present in Potamogale [V+00] (contra [A+02]: Potamogale is zalambdodont); M1 without mesially projecting parastyle [A+02$]; clavicle present (except Potamogale) [N99]; tail extremely variable, with some almost tailless while Microgale has 47 caudal vertebrae [N99]; cloaca present [V+00].

Note: [1] Adaptive radiation in Madagascar to fill all usual insectivore roles, with much morphological convergence. Potamogale, an otter-like aquatic form, and the smaller and less specialized Micropotamogale, have a highly disjunct distribution. They are found only in West and West Central Africa. [N99]. [2] Note the extreme generality and plasticity of this form. This may simply be due to its long isolation in Madagascar. On the other hand, it may be that tenrecs are a bit closer to the eutherian root than even the erinaceomorphs.

Links: Tenrecoidea Mikko's Phylogeny); Mitogenomic analyses of eutherian relationships are afrotherians); Eurasian Insectivores and Tree Shrews - Status Survey and ... taxonomic history); Anatomy of the oro-nasal region of some species of Tenrecidae and ... abstract); 食虫目 Chinese: brief discussion of phylogeny); Echinops telfairi are the sister group of elephants ... right).

References: Asher et al. 2002) [A+02]; Mouchaty et al. (2000) [M+00]; Nowak (1999) [N99]; Vaughan et al. 2000) [V+00]. ATW030721.

Solenodontidae: Solenodon.  May also include Nesophontes; but current view is that this is a separate and distantly related group.

Range: from the Pleistocene of the Caribbean [V+00].

Phylogeny: Soricomorpha:::  (Talpoidea + Soricoidea) + *.

Characters: Head and body 28-32.5 cm, with tail 17.5-25.5 cm and weight ~1 kg [N99]; general appearance as large, stout shrews [N99] [V+00]; head very large [A+02$]; skull long, slender; snout long, bare-tipped, supported at the base by a small round neomorphic os proboscidis [N99]; snout highly flexible & nearly hairless [V+00]; rostrum shows muscle scars corresponding to well muscled proboscis [A+02]; nares open laterally [N99]; eyes small [N99] [V+00]; skull nearly flat & constricted between orbits [N99]; lambdoid crest on the dorsal surface of the cranium, projects eave-like over occipital region [N99]; incomplete zygomatic arch; jugal absent; auditory bulla absent; pinnae prominent [N99] [V+00]; dentary with angular process at posteroventral corner broad & tapering [A+02$]; dentary condyle transversely expanded? [C88]; deciduous teeth replaced very early [C88]; dental formula 3/3, 1/1, 3/3, 3/3 [V+00]; I1 large and points slightly posteriorly [V+00]; diastema between I1 & I2 [N99]; i2 with deep groove for injection of toxic saliva, used as venom [N99] [V+00] [A+02$]; i2 trenchant & larger than other incisors [A+02$]; p3 with distinct cusp on distal margin [A+02$]; molars V-shaped, & primary cusp is paracone (zalambdodont) [A+02] [C88]; molars with tall, trenchant buccal ridge [V+00]; upper molars basically tricuspidate [V+00] (contra [A+02$: M1 & M2 with prominent hypocone); M3 paracone occludes with a basin between m3 hypoflexid & a cingulid [A+02$]; m2 mesial cingulid does not extend to buccal margin [A+02$]; m3 ?mesiodistally longer than other molars [A+02$]; tail nearly hairless [V+00]; feet large, clawed, 5/5, with claws larger & more curved on forelimbs [N99] [V+00]; tibia & fibula may fuse distally in older individuals [N99]; scent glands in armpit & groin [N99]; separate anal and urogenital openings [N99]; feed on animals (including insects), but also sometimes plant material [V+00]; root in ground with snouts or tear up rotten logs with claws [N99]; found in forests or brush, mainly nocturnal [N99] [V+00]; walk with awkward gait, digitigrade; incapable of jumping; can run surprisingly fast & can climb; some extensive tunnel systems in deep humus [N99]; may be social [1], with young sometimes remaining with the parents while subsequent litters are born and raised; stable dominance relationships [N99]; high-frequency (9-31 kHz) vocalizations may be used in echolocation [N99] [V+00].

Notes: [1] this is fairly unusual for insectivores, but is also found in some tenrecs.

Image: Right: Solenodon from APUS.RU | Щелезуб гаитянский which has several other nice images). Left: lower jaw detail from Solenodon. Note that image is upside-down on that page.

Links: Animal Diversity Web: Solenodontidae Family ADW; very good anatomical summary, with excellent images); APUS.RU | Род ·Щелезубы - Solenodon Russian: similar to previous site, with some additional information); Schlitzrüßler German: seems to have interesting notes on behavior); Solenodon; The Haitian or Hispaniolan Solenodon / Solenodon paradoxus excellent page on the very rare S. paradoxus); Animal Diversity Web: Gallery of Incisors-- what it says).

References: Asher et al. 2002) [A+02]; Carroll (1988) [C88]; Nowak (1999) [N99]; Vaughan et al. 2000) [V+00]. ATW030728.

Talpoidea: desmans, moles & shrew moles. Hesperoscalops. A rarely used clade, but useful to describe moles > hedgehogs, reserving "Talpidae" for the crown group of living moles (17 genera & ~35 species). At the moment, we actually draw no distinction, so all this erudition is wasted.

Range: from the Eocene of North America, Europe, Russia, Siberia, Central Asia & China; possibly South and Southeast Asia. Fossorial adaptations from the Miocene.

Phylogeny: Soricomorpha:::: Soricoidea + *.

Characters: head + body 6-22 cm [N99]; rostrum long, tubular, naked, extending beyond margin of lower lip [N99]; rostrum and manus) with high density of Eimer's organs (very sensitive touch receptors) [V+00]; eyes very small or covered with skin [N99] [V+00]; zygomatic arch complete [V+00]; pinnae usually absent [N99] [V+00]; bulla incomplete [V+00]; dentary condyle not transversely expanded [C88]; dentition 2-3/1-3, 1/0-1, 3-4/3-4, 3/3 [V+00]; I1 flat, without elongate crown [N99]; I1-2 inclined back [V+00]; upper molars with W-shaped ectolophs (dilambdodont) [C88] [N99] [V+00]; neck short [N99]; body generally cylindrical and elongate [N99]; sternum deeply keeled in burrowing forms [N99]; manubrium extended anteriorly below skull (increases attachment for pectoralisand moves shoulder anteriorly) [V+00]; clavicle short & robust [V+00]; clavicle providing secondary articulation for humerus, bracing humerus during rotation for digging motion [V+00]; scapula long & slender, anchoring forelimbs against axial skeleton & for origin of retractors [V+00]; humerus short & robust [V+00]; massive humerus receives radius in an S-shaped cavity, so that forelimbs are rotated with digits point laterally, palms ventral, & forelimb is almost vertical [V+00]; digits 5/5 [N99]; falciform may be enlarged to brace digit I more strongly against forearm [V+00]; phalanges short, unguals long; terminal phalanx with longitudinal groove or bilobed [N99] [2]; tibia & fibula fused distally [N99]; fur fine, soft, and of same length, without preferred orientation (but desmans also have long, oily specialized guard hairs) [N99] [V+00]; sensitive hearing, particularly low vibrations [N99]; two tunnel types: shallow tunnels pushed up with back & deeper permanent tunnels [N99]; rapid diggers, even in hard soil [N99]; several aquatic species which burrow only incidentally [N99]; usually, but not always solitary [N99].

Notes: [1] live in moister soils with permanent tunnel systems. [2] Unclear whether this applies to pes.

Image: right: from Gli Insettivori. Left: modified from [V+00].

Links: Basal Talpoidea Mikko's Phylogeny).

References: Carroll (1988) [C88]; Nowak (1999) [N99]; Vaughan et al. 2000) [V+00]. ATW030718.