Speciation of the Wandering Shrew - Part 10
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Part 10

_Marginal records._--CALIFORNIA: Pyramid Peak; near Mammoth; _Round Valley_; Bishop Creek; Mt. Whitney; Kern Lakes; Halstead Meadows; Horse Corral Meadows; east fork Indian Canyon (Jackson, 1928:121).

=Sorex vagrans parvidens= Jackson

_Sorex obscurus parvidens_ Jackson, Jour. Mamm., 2:161, August 19, 1921.

_Type._--Adult male, skin and skull; No. 56561, U. S. Biol. Surv.

Coll.; obtained on October 3, 1893, by J. E. McLellan from Thurmans Camp, Bluff Lake, 7500 ft., San Bernardino Mts., California.

_Range._--Confined, so far as known, to the San Bernardino and San Gabriel mountains, San Bernardino Co., California.

_Diagnosis._--Size medium for the species; measurements of two specimens from the San Bernardino Mountains are: total length, 105, 106; tail, 41, 48; hind foot, 12, 14. Upper parts in summer Olive-Brown to Buffy-Brown; cranium flattened and relatively narrow; unicuspids and incisors relatively small.

_Comparisons._--For comparison with _S. v. obscuroides_, the only adjacent subspecies, see the account of that subspecies.

_Remarks._--_S. v. parvidens_ is seemingly an uncommon mammal. I have been informed by Terry Vaughan that repeated attempts by him to obtain it in suitable habitat in the San Gabriel Mountains failed. This shrew is probably no longer in reproductive continuity with _Sorex vagrans_ of the Sierra Nevada.

_Specimens examined._--Total number, 4. CALIFORNIA: _San Bernardino Co._: type locality, 4 BS.

_Marginal records._--CALIFORNIA: Camp Baldy, San Antonio Canyon (Jackson, 1928:124); type locality.

=Sorex vagrans halicoetes= Grinnell

_Sorex halicoetes_ Grinnell, Univ. California Publ. Zool., 10:183, March 20, 1913.

_Sorex vagrans halicoetes_, Jackson, N. Amer. Fauna, 51:108, July 24, 1928.

_Type._--Young adult male, skin and skull; No. 3638, Mus. Vert. Zool.; obtained on May 6, 1908, by Joseph Dixon from salt marsh near Palo Alto, Santa Clara Co., California.

_Range._--Marshes in the southern part of San Francis...o...b..y, California.

_Diagnosis._--Size small for the species; measurements of two topotypes are: total length, 105, 106; tail, 39, 40; hind foot, 12, 13. Upper parts in winter Chaetura Black or near Fuscous-Black; underparts brownish; upper parts in summer near (17'_m_) Mummy Brown; underparts with a decided buffy wash, near (15'_d_) Light Ochraceous Buff; rostrum relatively large; maxillary tooth-row relatively long; teeth relatively large.

_Comparisons._--Darker ventrally, both summer and winter, than _S. v.

vagrans_; slightly more reddish dorsally in summer pelage than _S. v.

vagrans_, rostrum and teeth relatively larger; smaller externally than _S. v. paludivagus_, paler; skull longer, narrower cranially and broader rostrally.

_Remarks._--This subspecies seems to be restricted to salt marshes where it occurs with _Sorex ornatus_.

_Specimens examined._--Total number, 12. CALIFORNIA: _San Francisco Co._: San Francisco, 4 BS. _Alameda Co._: West Berkeley, 1 BS; Berkeley, 1 BS; Dumbarton Point, 1 KU. _San Mateo Co._: San Mateo, 2 BS. _Santa Clara Co._: Palo Alto, 3 BS.

_Marginal records._--CALIFORNIA: Berkley, _Elmhurst_; _Palo Alto_; San Mateo.

=Sorex vagrans paludivagus= von Bloeker

_Sorex vagrans paludivagus_ von Bloeker, Proc. Biol. Soc.

Washington, 52:93, June 5, 1939.

_Type._--Adult male, skin and skull; No. 5053, Los Angeles Museum of History, Science and Art, obtained on November 3, 1938, by Jack C. von Bloeker, Jr., from salt marsh at mouth of Elkhorn Slough, Moss Landing, Monterey Co., California, original no. 9456.

_Diagnosis._--Size medium for the species; average and extreme measurements of 6 topotypes are: total length, 115 (113-118); tail, 46.5 (42-48); hind foot, 14.5 (14-15) (von Bloeker, 1939:94). In winter nearly black dorsally, deep mouse gray ventrally; in summer nearly as dark dorsally as in winter, hairs of venter tipped with Clove Brown; skull short, relatively broad cranially and relatively narrow rostrally.

_Comparisons._--For comparison with _S. v. halicoetes_ see account of that subspecies.

_Remarks._--This subspecies, occurring at the limits of the range of the species, is uncommon in most collections. Seven specimens were available for the original description. The summer pelage is not completely described in the original description, but is stated to be darker than the winter pelage of _S. v. vagrans_, and must thus be considerably darker than the summer pelage of _S. v. halicoetes_. Two specimens in the Museum of Vertebrate Zoology, from San Gregario, referred by Jackson to _S. v. halicoetes_, were included in the present subspecies by von Bloeker.

_Specimens examined._--None.

_Records of occurrence_ (von Bloeker, 1939:94).--CALIFORNIA: _San Mateo Co._: San Gregario. _Monterey Co._: Seaside; mouth of Salinas River; Moss Landing.

_Marginal records._--CALIFORNIA: San Gregario; Seaside.

=Sorex vagrans vancouverensis= Merriam

_Sorex vancouverensis_ Merriam, N. Amer. Fauna, 10:70, December 31, 1895.

_Sorex vagrans vancouverensis_, Jackson, N. Amer. Fauna, 51:106, July, 1928.

_Type._--Adult male, skin and skull; No. 71913, U. S. Biol. Surv.

Coll.; obtained on May 10, 1895, by Clark P. Streator, from Goldstream, Vancouver Island, British Columbia.

_Range._--Vancouver Island from Sayward south, and Bowen Island.

_Diagnosis._--Size small for the species; average and extreme measurements of 6 specimens from Alberni Valley, Vancouver Island, are: total length, 106.5 (97-115); tail, 41.7 (40-43); hind foot, 12 (11-13) (Jackson, 1928:107). Ventral parts brownish, winter pelage reddish brown rather than grayish.

_Comparisons._--Differs from _S. v. vagrans_ in more brownish ventral parts and more brownish, rather than grayish, winter pelage; differs from the sympatric _S. v. isolatus_ in shorter tail, shorter hind foot, more narrow skull, and smaller teeth.

_Remarks._--This is a poorly differentiated subspecies which is closely related to _S. v. vagrans_. The differences in color noted are average ones. Some individuals of this shrew might be difficult to separate from _S. v. isolatus_. The slight degree of morphological divergence is such that intergrades might be expected to occur.

Possibly some habitat separation occurs, but such has not been reported.

_Specimens examined._--Total number, 3. BRITISH COLUMBIA: Vancouver Island: Mt. Washington, 1 KU; Nanaimo, 1 BS; type locality, 1 BS.

_Marginal records._--BRITISH COLUMBIA: Sayward (Anderson, 1947:18); Bowen Island (Hall, 1938:463); Alberni (Jackson, 1928:107).

CONCLUSIONS

1. _Sorex vagrans_, _S. obscurus_, _S. pacificus_, and _S. yaquinae_ are conspecific with one another. Each is a valid subspecies but all should bear the specific name _Sorex vagrans_ Baird, 1858.

2. The subspecies of _Sorex vagrans_ form a cline from large (_pacificus_) to small (_vagrans_). The cline is bent in such a manner that the terminal subspecies occur together. Where the two subspecies occur together, individuals of one subspecies do not crossbreed with individuals of the other subspecies and therefore react toward one another as do full species. _Sorex vagrans vagrans_ occurs sympatrically with _S. v. sonomae_, _S. v. pacificus_, _S. v.

yaquinae_, _S. v. bairdi_, _S. v. permiliensis_, and _S. v. setosus_.

_S. v. vancouverensis_ occurs sympatrically with _S. v. isolatus_.