Title: Four New Pocket Gophers of the Genus Cratogeomys from Jalisco, Mexico
Author: Russell, Robert J.
Language: English
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Four New Pocket Gophers
of the Genus Cratogeomys from Jalisco, Mexico


BY

ROBERT J. RUSSELL


University of Kansas Publications
Museum of Natural History

Volume 5, No. 31, pp. 535-542
October 15, 1953


University of Kansas
LAWRENCE
1953



UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY

Editors: E. Raymond Hall, Chairman, A. Byron Leonard,
and Robert W. Wilson

Volume 5, No. 31, pp. 535-542
October 15, 1953


UNIVERSITY OF KANSAS
Lawrence, Kansas


PRINTED BY
FERD VOILAND, JR., STATE PRINTER
TOPEKA, KANSAS
1953

24-8662



Four New Pocket Gophers
of the Genus Cratogeomys from Jalisco, Mexico

By

ROBERT J. RUSSELL


In the course of my taxonomic study of the genus _Cratogeomys_, a high
degree of variation was found between several populations of these
gophers in central Jalisco. Two species, _C. gymnurus_ and _C.
zinseri_, occur in this part of the state. Previously _C. gymnurus_ was
known only from southern Jalisco and _C. zinseri_ only from extreme
eastern Jalisco, but through the efforts of J. R. Alcorn specimens were
obtained of both species in the central part of the state. These large
gophers are difficult to collect, and I am grateful to him for securing
this significant material. Costs of the field work were defrayed by the
National Science Foundation and the Kansas University Endowment
Association. Thanks are due also to those in charge of the United
States Biological Surveys Collection for the loan of comparative
material. Study of the recently acquired specimens taken in central
Jalisco reveals two undescribed subspecies each of _C. gymnurus_ and
_C. zinseri_. These may be known and described as


=Cratogeomys gymnurus tellus= new subspecies

     _Type._--Female, adult, skull and skin, No. 33454 Mus. Nat.
     Hist., Univ. Kansas; from 3 mi. W Tala, 4300 ft., Jalisco,
     México; obtained on June 2, 1949, by J. R. Alcorn, original
     No. 9376.

     _Range._--North-central Jalisco; known from several
     localities in the vicinity of Tala.

     _Diagnosis._--Size large (see measurements); tail long,
     naked; hind foot small; color pale for species, upper parts
     Kaiser Brown (capitalized terms are of Ridgway, Color
     Standards and Color Nomenclature, Washington, D. C., 1912),
     bases of individual hairs Plumbeous, tips Hazel, underparts
     creamy-white, bases of hairs Plumbeous; skull large,
     relatively narrow, rugose; zygomatic breadth narrower
     posteriorly than anteriorly; rostrum shallow, relatively
     broad in males, narrower in females; interorbital region
     broad; braincase narrow and flattened; basioccipital
     relatively wide, especially anteriorly; mastoid processes of
     squamosal large, knoblike; paroccipital processes long,
     extending laterally over more than half the width of mastoid
     bullae; upper incisors projecting anteriorly; maxillary
     teeth relatively large.

     _Comparisons._--From topotypes of _C. g. gymnurus_ from
     Zapotlan, Jalisco, the most closely related subspecies, _C.
     g. tellus_ differs in: Body smaller (total length averaging
     338 instead of 341 in females and 356 instead of 369 in
     males); hind foot smaller (averaging 45 instead of 50 in
     females and 47 instead of 51 in males); color more brownish
     above, creamy-white rather than buffy below; skull smaller,
     especially in females (basilar length averaging 55.3 instead
     of 57.5 in females and 57.7 instead of 60.5 in males),
     narrower, and more rugose; zygomatic breadth less in females
     (averaging 42.5 compared with 46.2), greater in males (48.0
     compared with 46.7); zygomata more nearly parallel; auditory
     bullae relatively smaller; mastoid processes of squamosal
     larger, knoblike; paroccipital processes longer, extending
     farther laterally; rostrum less massive; upper incisors
     projecting anteriorly, instead of being strongly recurved;
     maxillary teeth relatively larger.

     From near-topotypes of _C. g. inclarus_ from the Sierra
     Nevada de Colima, Jalisco, _C. g. tellus_ differs in: Hind
     foot smaller; color paler brownish above in contrast to
     glossy black, creamy-white below rather than buffy, feet
     clothed with whitish instead of brownish hairs; skull larger
     (basilar length averaging 55.3 in females compared with
     53.2, no males available for comparisons); zygomatic breadth
     less; nasals longer, extending posterior to front edge of
     anterior roots of zygomata rather than ending even with, or
     slightly behind, them; rostrum more massive; mastoid
     processes of squamosal larger; paroccipital processes
     extending farther laterally; upper incisors projecting
     anteriorly, rather than recurved; maxillary teeth larger
     (length of maxillary tooth-row averaging 14.6 compared with
     13.3).

     Close comparison with _C. g. imparilis_ from Pátzcuaro,
     Michoacán, is not needed, _but C. g. tellus_ differs
     especially in: Color of underparts and hairs of feet whitish
     rather than brownish; skull smaller; zygomatic breadth
     greater; interorbital constriction broader; nasals longer;
     maxillary tooth-row longer.

     _Measurements._--Averages of three adult females, including
     type, and the measurements of an adult male (in parentheses)
     from the type locality are: Total length, 338 (356); length
     of tail, 92 (87); length of hind foot, 45 (47);
     occipitonasal length of skull, 64.1 (68.7); basilar length,
     55.3 (61.4); zygomatic breadth, 42.7 (48.0); interorbital
     breadth, 9.6 (11.4); greatest height of cranium, taken from
     palate perpendicular to line touching two highest points on
     top of skull, 23.9 (25.3); least depth of rostrum, 10.6
     (11.7); breadth of rostrum, 14.7 (16.5); length of nasals,
     23.6 (25.2); width across mastoid processes of squamosal,
     43.8 (49.7); height of occiput, 18.1 (19.9); length of
     maxillary tooth-row, 14.6 (15.2).

     _Remarks._--The distribution of _C. gymnurus_ is spotty; its
     occurrence seemingly depends on edaphic conditions. The
     isolation of soils with textures suitable to this animal has
     resulted in the isolation of gopher populations. The
     distribution is similar to that of species occurring on
     islands. In this instance, however, the populations of
     gophers are separated by soils of heavy texture which render
     burrowing difficult or impossible for gophers. Such
     conditions have led to a high degree of subspeciation in a
     relatively short distance. For example, four subspecies of
     _C. gymnurus_ occur in Jalisco, and, all are within an area
     scarcely fifty miles in diameter.

     _Cratogeomys gymnurus tellus_ is the northernmost subspecies
     of _C. gymnurus_. It is known from only the vicinity of
     Tala, west of Guadalajara, and its range probably is not
     much more extensive than this because of the localized
     distribution of suitable soils.

     _Specimens examined._--Total number ten, as follows: 3 mi. W
     Tala, type locality, 5; 1 mi. NE Tala, 3; 1 mi. S El
     Refugio, 2.


=Cratogeomys gymnurus atratus= new subspecies

     _Type._--Female, adult, skull and skin, No. 31880 Mus. Nat.
     Hist., Univ. Kansas; from Top of Cerro Viejo de Cuyutlán,
     9700 ft., 19 mi. S and 9 mi. W Guadalajara, Jalisco, México;
     obtained on February 17, 1949, by J. R. Alcorn, original No.
     7902.

     _Range._--Known only from the type locality on the Cerro
     Viejo.

     _Diagnosis._--Size small (see measurements); tail long; hind
     foot small; color dark, upper parts glossy Blackish Brown,
     bases of hairs Plumbeous, sides Chestnut Brown, underparts
     Pale Ochraceous-Buff or Warm Buff mixed with Plumbeous of
     the hair bases; skull small, lightly constructed, relatively
     deep; zygomata relatively weak; zygomatic breadth wider
     posteriorly than anteriorly; rostrum relatively wide,
     especially in males; nasals relatively long, truncate
     posteriorly; interorbital constriction narrow; braincase
     inflated; mastoid processes of squamosal only slightly wider
     than zygomatic breadth; auditory bullae relatively large;
     paroccipital processes weakly constructed, but extend
     laterally over half the width of mastoid bullae; upper
     incisors projecting anteriorly, rather than being strongly
     recurved; maxillary teeth small.

     _Comparisons._--From topotypes of _C. g. gymnurus_ from
     Zapotlan, Jalisco, _C. g. atratus_ differs in: Body smaller
     (total length averaging 300 in females compared with 341, a
     male measured 315 compared with an average of 363); tail
     shorter, hind foot smaller; color of upper parts darker,
     glossy Blackish-Brown rather than reddish brown, underparts
     paler; skull smaller (basilar length averaging 48.6 compared
     with 57.5, a male measured 50.0 compared with an average of
     59.0); zygomata more weakly constructed; zygomatic breadth
     less, and wider posteriorly than anteriorly; braincase more
     inflated; nasals shorter; rostrum relatively narrower and
     shallower; width across mastoid processes of squamosals
     less; paroccipital processes less strongly constructed,
     extending farther laterally; upper incisors projecting
     anteriorly rather than being strongly recurved; maxillary
     teeth smaller (length of maxillary tooth-row averaging 11.2
     compared with 14.9).

     From _C. g. tellus_, that occurs to the northwest, _C. g.
     atratus_ differs in: Body smaller; hind foot slightly
     smaller; upper parts darker; underparts Pale Ochraceous-Buff
     rather than creamy-white; skull smaller (see measurements);
     zygomatic breadth less, and wider posteriorly than
     anteriorly; nasals shorter, truncate posteriorly rather than
     emarginate; rostrum narrower and shallower; maxillary teeth
     smaller.

     From near-topotypes of _C. g. inclarus_ from the Sierra
     Nevada de Colima, _C. g. atratus_ differs in: Body slightly
     smaller; hind foot smaller (averaging 42 compared with 49);
     color of upper parts near the same, underparts paler; skull
     smaller, narrower, weaker in construction; zygomatic breadth
     less; nasals relatively longer, but actually shorter
     (averaging 19.7 compared with 20.3); upper incisors
     projecting anteriorly rather than being recurved; maxillary
     teeth smaller.

     _Measurements._--The type and an adult female (its
     measurements in parentheses) yield measurements as follows:
     Total length, 300 (299); length of tail, 78 (83); length of
     hind foot, 43 (40); occipitonasal length of skull, 56.3
     (55.5); basilar length, 49.3 (47.8); zygomatic breadth, 37.9
     (36.5); interorbital breadth, 8.7 (8.1); greatest height of
     cranium, as explained above, 21.6 (20.7); least depth of
     rostrum, 9.2 (8.8); breadth of rostrum, 12.8 (12.7); length
     of nasals, 19.4 (20.0); width across mastoid processes of
     squamosal, 38.2 (37.1); height of occiput, 16.9 (17.3);
     length of maxillary tooth-row, 11.9 (11.3).

     _Remarks._--_Cratogeomys gymnurus atratus_ is the smallest
     subspecies known for the species, and is so distinct from
     other described subspecies, that it is difficult to select
     one as the closest relative. In color, _C. g. atratus_
     closely resembles _C. g. inclarus_, which occurs at
     comparable elevations in the Sierra Nevada, but the skulls
     are unlike. Among named subspecies of _C. gymnurus_, the
     skull of _tellus_ most closely resembles that of _atratus_,
     and, although they differ greatly in size, _C. g. tellus_
     seems to be the closest relative of _C. g. atratus_.

     This newly described subspecies is known only from Cerro
     Viejo and is probably restricted to the higher elevations on
     this mountain.

     _Specimens examined._--Seven, Top of Cerro Viejo de Cuyutlán,
     19 mi. S and 9 mi. W Guadalajara.


=Cratogeomys zinseri zodius= new subspecies

     _Type._--Male, adult, skull and skin, No. 31879 Mus. Nat.
     Hist., Univ. Kansas; from 13 mi. S and 15 mi. W Guadalajara,
     Jalisco, México; obtained on February 6, 1949, by J. R.
     Alcorn, original No. 7747.

     _Range._--Known only from the type locality.

     _Diagnosis._--Size small (see measurements); tail short; hind
     foot small; upper parts Sayal Brown, underparts Pinkish Buff,
     hind foot whitish; skull small, narrow; outline of dorsal
     profile of skull concave; zygomatic breadth narrow; nasals
     actually short, but relatively long; width across mastoid
     processes of squamosal short; auditory bullae inflated;
     interorbital constriction narrow; maxillary teeth relatively
     large.

     _Comparisons._--From topotypes of _C. z. zinseri_ from Lagos,
     Jalisco, _C. z. zodius_ differs in: Body smaller (see
     measurements); tail shorter, hind foot smaller; upper parts
     dull brownish instead of reddish-brown, underparts paler,
     hairs of feet whitish instead of brownish; skull smaller,
     especially in females, narrower; dorsal profile of skull
     concave or flat (females) rather than convex; zygomatic
     breadth less; rostrum narrower and shallower; nasals actually
     shorter, but relatively longer in relation to length of
     skull; width across mastoid processes of squamosal shorter;
     maxillary teeth smaller.

     _Measurements._--The type and an adult male (his measurements
     in parentheses) yield measurements as follows: Total length,
     318 (324); length of tail, 95 (89); length of hind foot, 41
     (41); occipitonasal length of skull, 60.5 (59.1); basilar
     length, 52.4 (51.8); zygomatic breadth, 40.6 (39.0);
     interorbital breadth, 8.3 (8.8); greatest height of cranium,
     as explained above, 22.6 (22.4); least depth of rostrum, 11.2
     (10.4); breadth of rostrum, 13.3 (13.9); length of nasals,
     21.7 (21.2); width across mastoid processes of squamosal,
     37.1 (36.8); height of occiput, 17.7 (17.9); length of
     maxillary tooth-row, 13.0 (13.3). A nearly adult female
     measured: Total length, 292; length of tail, 81; length of
     hind foot, 39; occipitonasal length of skull, 53.3; basilar
     length, 46.5; zygomatic breadth, 34.1; interorbital breadth,
     7.8; greatest height of cranium, 21.0; least depth of
     rostrum, 9.8; length of nasals, 18.0; width across mastoid
     processes of squamosal, 32.2; depth of occiput, 15.9; length
     of maxillary tooth-row, 12.1.

     _Remarks._--This newly described subspecies is the smallest
     of known races of _C. zinseri_, and it is seemingly more
     closely related to _C. z. zinseri_ than to the subspecies
     newly named below from the north end of Lago Sayula. The
     skulls of females are especially small and delicate in
     structure; the males are larger with more massive skulls.
     _C. z. zodius_ is known to occur in the foot hills north of
     the Cerro Viejo, the mountain from which _C. g. atratus_ was
     described above.

     _Specimens examined._--Seven, 13 mi. S and 15 mi. W
     Guadalajara.


=Cratogeomys zinseri morulus= new subspecies

     _Type._--Male, adult, skull and skin, No. 36679 Mus. Nat.
     Hist., Univ. Kansas; from N end Lago Sayula, 4400 ft., 9 mi.
     N and 2 mi. E Atoyac, Jalisco, México; obtained on March 23,
     1950, by J. R. Alcorn, original No. 10889.

     _Range._--Known only from the type locality in central
     Jalisco.

     _Diagnosis._--Size large (see measurements); tail short;
     hind foot large; upper parts Fuscous-Black, strongly mixed
     with Walnut Brown, underparts Cinnamon-Buff, bases of all
     hairs Plumbeous; skull large, broad, rugose; outline of
     dorsal profile slightly concave, almost flat; zygomata
     strongly constructed, maxillary arm almost touching
     squamosal arm over jugal; wide across zygomata; nasals
     actually and relatively long; rostrum relatively narrow;
     auditory bullae inflated, relatively large; maxillary teeth
     relatively large.

     _Comparisons._--From topotypes of _C. z. zinseri_ from
     Lagos, Jalisco, _C. z. morulus_ differs in: Tail shorter
     (averaging 96 in females compared with 101, 94 in males
     compared with 115); color darker above, Fuscous-Black
     instead of Cinnamon-Rufous, underparts paler; skull larger
     (occipitonasal length 63.7 rather than averaging 58.5 in
     females and 68.6 rather than 63.1 in males); wide across
     zygomata; nasals actually and relatively longer; rostrum
     relatively narrower; wider across mastoid processes of
     squamosal; auditory bullae inflated, relatively larger;
     maxillary teeth larger.

     From _C. z. zodius_, that occurs to the northeast, _C. z.
     morulus_ differs in: Body larger (see measurements); hind
     foot larger; color of upper parts darker, underparts paler;
     skull much larger, broader, more rugose; dorsal profile of
     skull slightly concave rather than convex; wider across
     zygomata; nasals actually and relatively longer; rostrum
     broader, more massive; wider across mastoid processes of
     squamosal; auditory bullae larger; maxillary teeth larger.

     _Measurements._--The type and an adult female (her
     measurements in parentheses) from the type locality measure:
     Total length, 358 (338); length of tail, 94 (97); length of
     hind foot, 49 (45); occipitonasal length of skull, 68.6
     (63.7); basilar length, 58.0 (55.6); zygomatic breadth, 49.3
     (45.0); interorbital breadth, 9.6 (8.9); greatest height of
     cranium, as explained above, 26.1 (24.6); least depth of
     rostrum, 12.5 (10.8); breadth of rostrum, 14.5 (13.7);
     length of nasals, 25.9 (22.5); width across mastoid
     processes of squamosal, 47.7 (42.8); height of occiput, 19.8
     (17.8); length of maxillary tooth-row, 13.9 (13.8).

     _Remarks._--_Cratogeomys zinseri morulus_ is the darkest
     subspecies known of _C. zinseri_. It differs widely from
     other subspecies of this species in color and the large size
     of the skull.

     _Cratogeomys zinseri_ occurs over the same general area as
     _C. gymnurus_ in central Jalisco, although these two species
     seemingly do not share the same local habitat. _C. zinseri_
     differs from _C. gymnurus_ as follows: Tail relatively
     longer; skull wider across zygomatic arches than across
     mastoid processes of squamosal (reverse true in _C.
     gymnurus_); zygomata strongly bowed outward anteriorly;
     maxillary arm of zygomata almost touching squamosal arm
     (instead of widely separated from each other) above jugal;
     rostrum relatively narrower, less massive; border of nasals
     parallel or laterally swollen instead of gradually tapering.

     _Specimens examined._--Four, N end of Lago Sayula, 9 mi. N
     and 2 mi. E Atoyac.


_Museum of Natural History, University of Kansas, Lawrence. Transmitted
June 12, 1953._


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Transcriber's Notes:

Page 538: Changed lead to led (conditions have lead to a high degree).

Bold text is shown within =equal signs=.

Italicized text is shown within _underscores_.





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