[591]

University of Kansas Publications

Museum of Natural History

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Volume 7, No. 12, pp. 591-608

  March 15, 1955  

 

Geographic Variation in the Pocket Gopher,
Cratogeomys castanops, in Coahuila, México

 

 

BY

ROBERT J. RUSSELL AND ROLLIN H. BAKER

 

 

 

 

University of Kansas

Lawrence

1955

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[592]

University of Kansas Publications, Museum of Natural History


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

 

 

Volume 7, No. 12, pp. 591-608

Published March 15, 1955

 

 

 

University of Kansas

Lawrence, Kansas

 

 

PRINTED BY

FERD VOILAND, JR., STATE PRINTER

TOPEKA, KANSAS

1955



25-5679

[593]

The plateau pocket gopher, Cratogeomys castanops, inhabits open
lands from southeastern Colorado southward onto the Mexican
Plateau as far south as southern San Luis Potosí and southeastern
Zacatecas and southeastward to the Coastal Plain of northern Tamaulipas.
This species occurs at elevations from as low as 26 feet at
Matamoras in Tamaulipas to as high as 8700 feet in valleys of south-eastern
Coahuila. In 1934, Nelson and Goldman (Proc. Biol. Soc.
Washington, 47:135-154, June 13, 1934) revised the genus
Cratogeomys and decided that six subspecies of C. castanops occurred
in Coahuila. In the present account, we describe four
previously unknown subspecies from Coahuila, exclude from the
state two others recorded from there by Nelson and Goldman, and
show that three others named previously from adjacent Mexican
states do occur in Coahuila. This makes eleven subspecies now
known from that state. From Coahuila Nelson and Goldman had
35 study specimens of C. castanops from seven localities and we
have had 234 specimens from 63 localities. Consequently we have
been able to define with greater certainty, than formerly was possible,
the geographic distribution of C. castanops in this Mexican
state and similarly analyze more completely the geographic variation.

Coahuila is near the center of the geographic range of C. castanops.
The occurrence of 11 subspecies within the state seems to be
the result of partial or perhaps, in some cases, total isolation of populations
of C. castanops because of the highly dissected topography
and the variability of the soil. Cratogeomys castanops is a sedentary
animal preferring open plains mantled by suitable soils, preferably
sandy in texture, in which the animals can dig their elaborate
underground systems of runways. Thin soils of hard texture and
rocky soils do not offer optimum habitat for C. castanops, and the
animals usually are absent or uncommon in such situations. Desert
mountains with their thin rocky soils, elevated passes, perpendicular
rocky cliffs, and stands of oaks and conifers at higher elevations
present impassable barriers for pocket gophers of this species. The
Río Grande, bordering Coahuila to the north, in many places flowing
[594]
through steep-walled cañons, also seems to be a barrier that this
fossorial rodent does not cross; distinct subspecies occur on the two
sides of the river directly opposite each other (also see Nelson and
Goldman, op. cit.: 143). Smaller streams, such as the Río Salado,
Río Nazas and Río Salinas, seem to be unimportant barriers to the
passage of these pocket gophers. The food supply of C. castanops
seems adequate in most situations and consequently food is unimportant
in governing the distribution of this species. Principal foods
of C. castanops are fleshy tuberous roots of well-distributed desert
shrubs, but in the valleys of the high mountains of southeastern
Coahuila, where desert shrubs are absent, roots and leaves of low-growing
forbs are eaten.

Three distinct habitats for C. castanops occur in Coahuila. The
state is crossed by a series of mostly impassable, mountainous ridges
beginning at the northwestern boundary at the Cañon de Boquillas
on the Río Grande and extending southeastward to the east-central
border. This divides Coahuila into a more humid and less elevated
northeastern area which is an inland extension westward of the
Coastal Plain and a more arid and higher western and southern
area which is a part of the "Mesa del Norte" of the Mexican Plateau.
In the extreme southeast the still higher elevated plains and intermontane
valleys within the Sierra Madre Oriental afford a third
habitat for populations of this species. The subspecies of these
pocket gophers found in any one of these three habitats show greater
affinity to each other than they do to any subspecies found in the
other habitats.

Generally speaking, populations of C. castanops from northeastern
Coahuila are related, as a group, in color and cranial features.
Partial isolation of subspecies in this area results chiefly from discontinuity
of suitable soils rather than from topography. These
pocket gophers occur most commonly in the deep, sandy soils which
are found along streams, especially where farm lands are irrigated.
In western and southern Coahuila, mountains extending in both
north-south and east-west directions act as partial barriers to the
passage of C. castanops. Within this large area, pocket gophers
occur in desert basins many of which are enclosed on two or more
sides by mountains. Even so, with the exception of the smaller C.
c. consitus of northwestern Coahuila, all known subspecies occurring
at lower elevations in the western and southern part of the state
show close relationships in color and cranial features. Those subspecies
in the higher parts of southeastern Coahuila by their small
[595]
size and dark color reflect to a high degree their isolation in an
elevated habitat.

Males of C. castanops differ greatly from females of equal age;
consequently animals of the same sex, as well as of the same age,
are used herein for taxonomic comparisons. Since, of any given
age-group, females show less individual variation than do males, we
have relied more on the characteristics of the females in this taxonomic
study. Only specimens taken at approximately the same
times of the year have been compared for color of pelage. Capitalized
color terms are those of Ridgway, Color Standards and Color
Nomenclature, Washington, D. C., 1912. Specimens made available
through the courtesy of the authorities of the Biological Surveys Collection
of the United States National Museum are indicated in the
accounts of subspecies as BSC; other specimens listed are in the
collection of the University of Kansas Museum of Natural History.
Assistance with field work is acknowledged from the Kansas University
Endowment Association and the National Science Foundation.

In any one of the lists of "Specimens examined" beyond, the order
of arrangement of the localities is from north to south. Those localities
listed in Roman type are represented on the distribution map
(Figure 1) by blacked-in circles. Each of several circles covers
two or more localities because the localities are close together. In
any such instance the northernmost place is listed in Roman type
and the names of the other places follow in Italic type. Measurements
in millimeters are given in table 1 for females and in table 2
for males.

Distribution.--Extreme northern Coahuila, east and north of the Serranías
del Burro (see fig. 1).

Diagnosis.--Previously known from only one specimen, a subadult female,
this subspecies has not been well diagnosed. At hand we have five near topotypes
of convexus (including two adult females and one adult male) and specimens
assignable to this subspecies from several other localities. This subspecies
may be characterized as follows: Size medium (see tables 1 and 2); dorsal
profile of skull convex in females and flat, especially posteriorly, in males;
zygomata weakly constructed and not widely flaring; mastoid and tympanic
bullae inflated; nasals short; rostrum broad and short; maxillary teeth large.

[596]

Fig. 1. Geographic ranges of the subspecies of Cratogeomys castanops

found in Coahuila, México.

Click on ap to view larger sized.

[597]
Comparisons.--From topotypes of Cratogeomys castanops angusticeps Nelson
and Goldman, found to the north and east across the Río Grande in Texas,
convexus differs in: Body larger; upper parts more reddish, especially on sides;
skull with zygomata less heavy, nasals broader, pterygoids smaller, maxillary
teeth larger. For comparisons of convexus with the subspecies of C. castanops
found to the west, south and southeast, see accounts of the subspecies to follow.

Specimens examined.--Total, 14, all from Coahuila: Río Grande, 17 mi. S
Dryden, Terrell Co., Texas, 6; Río Grande, opposite Samuels, Val Verde Co.,
Texas, 1 (BSC); Villa Acuña, 5; Cañon del Cochino, 21 mi. E and 16 mi. N
Piedra Blanca, 1; 11 mi. W Hda. San Miguel, 1.

Type.--Female, adult, skin and skull, No. 48498, Univ. Kansas Mus. Nat.
Hist., 2 mi. S and 6-1/2 mi. E Nava, 810 ft., Coahuila; 16 June 1952; obtained by
Robert J. Russell, original number 276.

Distribution.--Desert lowlands of northeastern Coahuila, from the Río
Grande to as far southwestward as the Río Sabinas (see fig. 1).

Diagnosis.--Body medium for the species (see tables 1 and 2); tail long;
hind foot small; upper parts Light Ochraceous-Buff (in summer pelage) and
Orange-Buff (in winter pelage), bases of hairs Plumbeous; underparts white
to pale buffy; skull small, broad and slightly convex in dorsal outline; zygomata
widely flaring; palate short; rostrum short; nasals short; mastoid and tympanic
bullae inflated; basioccipital with lateral edges parallel; maxillary teeth small.

Comparisons.--From Cratogeomys castanops convexus, found to the north,
bullatus differs in: Hind foot shorter; skull much broader in relation to length;
rostrum narrower but, relative to length of skull, wider; tympanic bullae
slightly more inflated; incisors and maxillary teeth smaller. From topotypes of
Cratogeomys castanops angusticeps, found across the Río Grande and upstream
from localities where bullatus is known to occur, bullatus differs in: Body
slightly smaller; color paler, especially on sides; skull shorter and broader;
rostrum shorter and broader; nasals shorter; mastoid and tympanic bullae more
inflated; maxillary teeth smaller. For comparisons of bullatus with the subspecies
of C. castanops found to the west and south, see accounts of the subspecies
to follow.

Specimens examined.--Total, 24, from: 2 mi. S and 6-1/2 mi. E Nava, 810 ft.,
2; 2 mi. S and 12 mi. E Nava, 800 ft., 1; 3 mi. S and 12 mi. E Nava, 800 ft.,
4; 29 mi. N and 6 mi. E Sabinas, 5; 10 mi. E Hacienda La Mariposa, 2000 ft.,
1; La Gacha [= La Concha], 1600 ft., 8; 8 mi. S and 8 mi. E Hacienda La
Mariposa, 1900 ft., 1; 9 mi. S and 11 mi. E Sabinas, 1050 ft., 2.

Type.--Female, adult, skin and skull, No. 34589, Univ. Kansas Mus. Nat.
Hist., Don Martin, 800 ft., Coahuila; 19 August 1949; obtained by W. Kim
Clark, original number 1034.

Distribution.--Extreme northeastern Coahuila from the vicinity of Presa
Don Martin southward into northwestern Neuvo León in the valley of the Río
Salado and its tributaries at least as far south as the vicinity of Vallecillo (see
fig. 1).

Diagnosis.--Body large for species (see tables 1 and 2); hind foot short;
upper parts Apricot Buff (in fresh summer pelage) and Salmon-Buff strongly
mixed with black (in fresh winter pelage); underparts Light Ochraceous-Buff;
skull large, especially in females, and broad; zygomatic arches widely flaring;
palate long; rostrum broad; nasals long; mastoid and tympanic bullae not conspicuously
inflated; incisors narrow; maxillary teeth large.

Comparisons.--From Cratogeomys castanops bullatus found to the north,
ustulatus differs in: Body larger; tail shorter; upper parts darker, more rufous
and less buffy; skull larger, especially in palate, nasals, and rostrum; zygomata
more widely flaring; tympanic bullae less inflated; incisors slightly larger; maxillary
teeth larger. From topotypes of Cratogeomys castanops tamaulipensis
found to the southeast, ustulatus differs in: Body larger; upper parts, in winter
[599]
pelage, darker, more rufous and less buffy; underparts paler; skull larger, especially
in palate, rostrum and nasals; zygomata more widely flaring; tympanic
bullae more inflated; pterygoids larger; basioccipital narrower, its sides parallel
instead of convex; maxillary teeth smaller. From Cratogeomys castanops subsimus,
found to the southwest, ustulatus differs in: Tail shorter; hind foot
smaller; upper parts darker, more rufous and less pinkish-buff; skull shorter;
zygomata less widely flaring; palate shorter; rostrum averaging slightly narrower;
nasals shorter; incisors narrower; maxillary teeth slightly smaller. For comparison
of ustulatus with the subspecies of C. castanops to the southwest, see account
of that subspecies to follow.

Specimens examined.--Total, 10, from: Don Martin, 800 ft., 5; base of Don
Martin Dam, 2; 2 mi. SE Don Martin Dam, along Río Salado, 2; 5 mi. SE Don
Martin, 1.

Records from Nuevo León.--Total, 14, from: 9 mi. N and 2 mi. W Anahuac
[= Rodríques], 1; 4 mi. N and 1 mi. W Anahuac [= Rodríques], 5; 3 mi. N
Lampazos, 4; 1 mi. N Vallecillo, 1000 ft., 1; Vallecillo, 20 mi. S Río Salado,
1000 ft., 3.

Type.--Female, adult, skin and skull; No. 56603, Univ. Kansas Mus. Nat.
Hist.; Hermanas, 1205 ft., Coahuila; 5 December 1953; obtained by Robert
W. Dickerman, original number 2051.

Distribution.--Arid plains and broad intermontane valleys of east-central
Coahuila (see fig. 1).

Diagnosis.--Body largest for the species (see table 1); tail long; hind foot
large; upper parts in winter pelage Ochraceous-Buff, in summer pelage Antimony
Yellow; underparts Pale Ochraceous-Buff; skull medium in size, broad; zygomata
moderately flaring; palate medium in length; rostrum broad; nasals moderately
long; maxillary teeth small.

Comparisons.--From Cratogeomy castanops ustulatus, found to the east,
jucundus differs in: Body larger; tail longer; hind foot larger; upper parts paler,
more ochraceous and less rufous; skull averaging smaller; zygomata slightly less
expanded laterally; palate and nasals shorter; squamosal breadth less; mastoid
bullae less inflated, especially in females; rostrum slightly narrower; maxillary
tooth-row shorter. From topotypes of Cratogeomys castanops tamaulipensis,
found to the southeast, jucundus differs in: Body larger; tail longer; hind foot
[600]
smaller; upper parts, in winter pelage, paler, more ochraceous and less rufous;
skull larger; zygomata more widely flaring; palate longer; rostrum broader;
tympanic bullae more inflated; basioccipital with sides parallel instead of convex;
maxillary teeth smaller. From Cratogeomy castanops excelsus, found to
the southwest, jucundus differs in: Body larger; hind foot averaging larger;
upper parts darker, more ochraceous, and less buffy; underparts darker, more
buffy and less whitish; skull slightly smaller; zygomata less widely flaring, especially
in females; palate shorter; nasals shorter; squamosal breadth less;
mastoid bullae more inflated; incisors narrower. From Cratogeomys castanops
subsimus, found to the south, jucundus differs in: Body larger; tail shorter;
hind foot shorter; upper parts paler, more ochraceous and less yellowish; skull
smaller; zygomata less widely expanded laterally; palate and nasals shorter;
rostrum narrower; squamosal breadth less; maxillary tooth-row shorter. From
Cratogeomys castanops bullatus, found to the north, jucundus differs in: Body
larger; tail averaging longer; hind foot larger; color of upper parts more
ochraceous and less rufous; underparts darker, more buffy and less whitish;
skull larger, especially in length, in width across zygomata, in lengths of
palate, rostrum and nasals; mastoid and tympanic bullae less inflated; squamosal
breadth greater.

Specimens examined.--Total, 19, from: Hermanas, 1205 ft., 9; 1 mi. S
Hermanas, 2; 1 mi. N and 13 mi. E Cuatro Ciénegas, 2; 5 mi. N and 2 mi. W
Monclova, 1; 2 mi. N and 1 mi. E Monclova, 1; Monclova, 2 (BSC); Hisachalo
[= Huisachalo], 2.

Type.--Female, adult, skin and skull; No. 56614, Univ. Kansas Mus. Nat.
Hist.; 1.5 mi. NW Ocampo, 3300 ft., Coahuila; 16 December 1953; obtained
by Robert W. Dickerman, original number 2164.

Distribution.--Desert plains of north-central Coahuila, surrounded for the
most part by higher mountainous country (see fig. 1).

Diagnosis.--Body large for species (see tables 1 and 2); tail short; hind foot
large; upper parts Ochraceous-Buff (in summer pelage) and Orange-Buff (in
fresh winter pelage); underparts Pale Ochraceous-Salmon; skull medium in size
and narrow; zygomata narrow; rostrum narrow; palate short; nasals medium in
length; basioccipital small and narrow; mastoid bullae not greatly inflated;
tympanic bullae inflated; incisors small; maxillary teeth small.

[601]
Comparisons.--From Cratogeomys castanops jucundus, found beyond the
mountains to the southeast, sordidulus differs in: Body smaller; tail shorter;
hind foot slightly smaller; upper parts darker, more ochraceous and less yellowish,
with plumbeous bases of hairs more conspicuous; underparts darker, more
buffy and less whitish; skull slightly shorter, more nearly flat, and narrower;
zygomata less widely flaring; rostrum narrower; mastoid bullae less inflated;
incisors and maxillary teeth slightly smaller. From Cratogeomys castanops
excelsus, found to the south and southwest, sordidulus differs in: Body slightly
smaller; tail shorter; hind foot slightly larger; upper parts darker, more ochraceous
and less pinkish-buff; underparts darker, more buffy and less whitish; skull
smaller and narrower; zygomata less widely flaring; sides more nearly parallel
and not expanded anteriorly; palate shorter; rostrum narrower and, in relation
to greatest length of skull, longer; tympanic bullae slightly more inflated; incisors
and maxillary teeth smaller. From Cratogeomys castanops consitus, found to
the north and west, sordidulus differs in: Body larger; hind foot larger; upper
parts paler, more ochraceous and less rufous; skull decidedly larger and wider;
zygomata more widely flaring; palate and nasals longer; rostrum broader;
mastoid bullae and tympanic bullae larger; maxillary teeth smaller. From
topotypes of Cratogeomys castanops clarkii (Baird), found to the northwest,
sordidulus differs in: Body larger; tail shorter; upper parts, in winter pelage,
paler, more ochraceous and less dark-rufous; skull slightly smaller and narrower;
rostrum narrower; nasals slightly shorter; sides of basioccipital more nearly
parallel instead of wedge-shaped; mastoid bullae less inflated; incisor and
maxillary teeth smaller. From Cratogeomys castanops convexus, found to the
northeast, sordidulus differs in: Body larger; tail shorter; upper parts slightly
darker, more ochraceous and less buffy; skull narrower; zygomata more nearly
parallel and less expanded anteriorly; rostrum narrower and longer; nasals
longer; squamosal breadth greater; mastoid bullae less inflated; maxillary teeth
smaller. From Cratogeomys castanops bullatus, found to the east, sordidulus
differs in: Body larger; hind foot larger; upper parts darker, more ochraceous
and less buffy; skull larger in all respects; zygomata more widely flaring;
tympanic bullae less inflated; maxillary teeth larger.

[602]

Specimens examined.--Total, 13, from: 50 mi. N and 20 mi. W Ocampo,
4150 ft., 1; 18 mi. S and 14 mi. E Tanque Alvarez, 4000 ft., 4; 1-1/2 mi. NW
Ocampo, 3300 ft., 6; Ocampo, 1; 5 mi. N and 19 mi. W Cuatro Ciénegas, 3250
ft., 1.

Distribution.--Arid high plains from central Chihuahua, east and southeast
at least into northwestern Coahuila (see fig. 1).

Comparisons.--From Cratogeomys castanops lacrimalis Nelson and Goldman,
specimens from Boquillas and Marathon north of the Río Grande in Texas,
consitus differs in: Body smaller; tail and hind foot shorter; upper parts paler,
more light buffy and less rufous; underparts paler, light buffy instead of dark
buffy; skull decidedly smaller; zygomata slightly less widely flaring; palate especially
shorter; rostrum narrower; squamosal breadth less; incisors smaller.
From topotypes of Cratogeomys castanops clarkii, found to the north along the
Río Grande, consitus differs in: Body smaller; tail and hind foot shorter; upper
parts paler, more buffy and less rufous; skull markedly smaller, especially in
palate and nasals; zygomata less widely flaring; tympanic bullae more inflated;
mastoid bullae less inflated; basioccipital parallel-sided as opposed to wedge-shaped.
From Cratogeomys castanops convexus, found to the east, consitus
differs in: Body smaller; tail and hind foot shorter; upper parts paler, more
buffy and less ochraceous; underparts paler, white or light buffy instead of pale
ochraceous; skull smaller; zygomata less widely flaring; palate shorter; rostrum
decidedly narrower and, relative to length of skull, longer; squamosal breadth
less; incisors smaller. From Cratogeomys castanops excelsus, found to the
south, consitus differs in: Size smaller; tail and hind foot shorter; upper parts
darker, more rufous and less pinkish-buff; skull conspicuously smaller, especially
in palate, rostrum, and nasals; zygomata less widely flaring; mastoid
bullae and tympanic bullae more inflated; incisors smaller; maxillary teeth relatively
larger. For comparison of consitus with Cratogeomys castanops sordidulus,
see previous account.

Specimens examined.--Total, 8, from: 3 mi. N and 9 mi. E El Pino, 1; 6
mi. E Jaco, Chihuahua, in Coahuila, 6; 3 mi. NE Sierra Mojada, 1.

[603]

Distribution.--Desert plains of southwestern Coahuila and northeastern
Durango (see fig. 1).

Comparisons.--Cratogeomys castanops excelsus is characterized by large
size and pale color; it is the palest subspecies of C. castanops. Of adjacent subspecies,
excelsus most closely resembles C. c. subsimus which occurs to the east
and resembles least C. c. consitus, which occurs to the northwest.

From Cratogeomys castanops subsimus, found to the east, excelsus differs
in: Body averaging slightly larger; tail and hind foot shorter; upper parts paler,
more light buffy and less yellowish; skull smaller; palate especially shorter;
rostrum narrower; nasals shorter; incisors slightly smaller; maxillary tooth-row
shorter. Compared with topotypes of C. c. goldmani, found to the south,
excelsus differs in: Body larger; hind foot smaller; upper parts in winter pelage
paler, more buffy and less rufous; skull larger; zygomata more widely flaring;
rostrum broader; nasals shorter; tympanic bullae larger and more inflated;
maxillary teeth larger.

Specimens of excelsus from the vicinity of Torreón, in southwestern Coahuila,
are slightly smaller in cranial dimensions than more typical examples of the subspecies.
In small size, at least, these specimens show some resemblance to
goldmani to the south. The range of excelsus approaches that of C. c. consitus
in west-central Coahuila (see fig. 1), but no evidence of intergradation between
these two subspecies could be ascertained. For comparison of excelsus
with consitus, see account of the latter.

Specimens examined.--Total, 33, from: 8 mi. E and 2 mi. S Americanos,
3500 ft., 3; 4 mi. N Acatita, 3600 ft., 9; 20 mi. S El Hundido, 1; San Pedro, 2
(BSC); 1 mi. SW San Pedro de las Colonias, 3700 ft., 4; 10 mi. N and 11 mi.
W San Lorenzo, 2; 2 mi. E Torreón, 12.

Distribution.--Desert plains and lower foothills of mountains in south-central
Coahuila (see fig. 1).

Comparisons.--From Cratogeomys castanops goldmani, found to the southwest,
subsimus differs in: Body larger; hind foot larger; upper parts paler, more
yellowish and less rufous; skull larger and rougher, having more prominent
ridges and crests and deeper fossae for attachment of muscles; zygomata more
widely flaring; palate longer; rostrum broader; nasals longer; squamosal breadth
greater; maxillary teeth larger. From C. c. subnubilus, found to the south,
subsimus differs in: Body larger; tail and hind foot shorter; upper parts paler,
more yellowish-buff and less blackish; skull decidedly larger in all respects.
From C. c. planifrons, found at higher elevations to the southeast, subsimus differs
in the same respects as subsimus differs from subnubilus. For comparisons
between subsimus and subspecies to the west, north and northeast, see accounts
above.

TABLE 1. Measurements of Adult Female Cratogeomys from
Coahuila, México

Table legend: Column A: No. av. or cat. no. Column B: Total length Column C: Length of tail Column D: Length of hind foot Column E: Condylobasal breadth Column F: Zygomatic breadth Column G: Length of palate Column H: Breadth of rostrum Column I: Length of nasals Column J: Squamosal breadth Column K: Alveolar length of maxillary tooth-row

A	B	C	D	E	F	G	H	I	J	K
C. c. convexus, Villa Acuña
52259	260	86	37	50.6	31.7	33.8	11.7	16.7	29.1	9.3
52261	265	83	38	49.3	31.6	32.9	11.8	15.8	28.9	10.6
C. c. bullatus, vicinity of Nava
5 Av.	256	80	36	47.4	30.6	32.6	10.7	17.1	27.9	9.5
Min.	242	72	35	47.0	30.6	32.3	10.0	16.5	27.5	9.2
Max.	263	85	37	47.7	31.1	32.9	11.6	17.8	28.2	9.8
C. c. ustulatus, vicinity of Don Martin
8 Av.	273	74	36	51.4	33.5	35.4	11.8	18.8	30.1	10.0
Min.	261	64	35	50.7	32.6	34.8	11.0	17.8	29.1	9.3
Max.	280	83	38	52.1	34.1	36.5	12.5	19.2	30.8	10.6
C. c. jucundus, Hermanas
4 Av.	296	85	39	50.9	33.0	34.6	11.5	18.0	29.6	9.4
Min.	294	83	38	49.8	32.1	33.8	11.0	17.0	29.0	9.1
Max.	298	86	39	51.8	33.8	35.0	11.6	18.6	30.1	9.6
C. c. sordidulus, 1.5 mi. NW Ocampo
3 Av.	276	79	37	50.4	31.7	34.6	10.9	18.2	30.0	9.1
Min.	270	75	36	49.5	30.6	33.8	10.3	17.7	29.8	8.9
Max.	288	85	39	51.4	32.4	35.2	11.4	18.5	30.1	9.2
C. c. consitus, 6 mi. E Jaco, Chihuahua, in Coahuila
4 Av.	229	74	32	43.8	28.1	29.6	9.7	16.0	26.2	8.9
Min.	226	68	31	42.6	27.3	29.4	9.4	15.5	25.7	8.1
Max.	232	78	32	45.8	28.8	29.9	9.9	16.2	26.9	9.2
C. c. excelsus, 4 mi. N Acatita
4 Av.	284	82	37	51.4	34.1	35.4	11.6	18.9	31.2	9.5
Min.	274	77	35	51.1	33.6	34.7	10.4	18.4	30.5	9.2
Max.	291	86	38	51.6	34.9	36.1	12.1	20.1	31.7	9.9
C. c. subsimus, 12 mi. N and 10 mi. E Parras
34937	287	87	39	53.1	34.9	36.9	11.5	19.4	31.7	10.5
Jaral (BSC)
51049	295	104	40	53.2	34.1	36.9	12.6	18.7	29.7	10.0
C. c. goldmani, 1 mi. S Jimulco
55611	250	85	35	46.0	32.6	31.4	10.7	16.3	27.8	9.8
C. c. subnubilus, 1 mi. S Carneros
33128	220	65	29	40.8	27.9	27.2	8.7	12.7	24.7	8.1
2 mi. W San Miguel
33132	222	65	30	40.4	26.3	26.6	8.1	13.2	24.5	8.4
1 mi. N Agua Nueva
33127	220	74	29	41.8	24.6	28.4	8.3	14.2	23.9	8.4
8 mi. N La Ventura
34934	235	76	30	42.2	27.9	28.5	9.0	14.3	26.3	7.8
C. c. planifrons, 12 mi. W San Antonio de las Alazanas
5 Av.	244	66	32	43.7	28.0	29.1	9.4	14.5	26.2	8.6
Min.	239	62	31	43.3	27.5	28.7	8.9	13.6	25.3	8.3
Max.	247	69	33	44.3	28.5	9.4	9.7	15.3	26.8	8.9

TABLE 2. Measurements of Adult Male Cratogeomys from
Coahuila, México

Table legend: Column A: No. av. or cat. no. Column B: Total length Column C: Length of tail Column D: Length of hind foot Column E: Condylobasal breadth Column F: Zygomatic breadth Column G: Length of palate Column H: Breadth of rostrum Column I: Length of nasals Column J: Squamosal breadth Column K: Alveolar length of maxillary tooth-row

A	B	C	D	E	F	G	H	I	J	K
C. c. convexus, Villa Acuña
52260	275	89	39	55.0	34.4	37.0	12.6	20.0	30.9	10.4
C. c. bullatus, 3 mi. S and 12 mi. E Nava
48500	261	80	36	49.7	35.3	34.4	12.4	17.1	29.2	9.5
La Gacha
57028	250	76	34	49.9	34.0	34.4	11.5	16.6	28.4	9.3
C. c. ustulatus, Don Martin
34587	280	75	37	54.6	37.3	38.2	13.7	20.6	31.8	10.3
C. c. jucundus, Hermanas
56605	311	80	42	56.9	38.7	40.1	13.3	21.0	32.3	9.9
C. c. sordidulus, 1.5 mi. NW Ocampo
56733	307	88	37	57.5	49.6	40.3	13.6	22.1	33.1	10.3
C. c. consistus, 3 mi. N and 9 mi. E El Pino
54547	289	94	36	53.8	32.6	37.1	12.7	18.8	29.5	9.6
C. c. excelsus, 2 mi. E Torreón
40224	315	97	41	54.7	37.8	37.6	12.1	19.5	31.4	9.8
C. c. subsimus, Hda. El Tulillo, 5 km. S Hipolito
35772	315	105	40	56.4	35.3	39.5	12.5	20.8	33.8	10.6
2 mi. N Santa Cruz
48517	316	89	40	58.2	37.9	40.3	14.1	21.7	34.8	10.3
C. c. goldmani, W foot Pico de Jimulco
55610	255	82	36	48.9	33.4	33.4	11.7	17.7	29.6	9.3
C. c. subnubilus, Carneros (BSC)
79484	247	86	34	45.3	30.9	30.8	9.6	15.7	28.4	8.5
8 mi. N La Ventura
34932	250	79	34	46.3	31.8	31.0	9.6	16.4	28.7	8.4
C. c. planifrons, 4 mi. S and 6 mi. E Saltillo
35779	254	76	34	48.0	32.2	32.6	9.8	16.6	28.0	8.6
35780	272	85	35	48.8	33.2	34.1	10.5	17.5	29.9	9.5
12 mi. S and 2 mi. E Arteaga
33122	255	72	35	47.0	32.3	31.2	10.5	15.5	28.7	9.0

[606]

Specimens examined.--Total, 22, from: 3 mi. S and 3 mi. E Muralla, 3800 ft.,
3; 2 mi. N Santa Cruz, 2; 21 mi. S and 11 mi. E Australia, 4400 ft., 6; Jaral, 3860
ft., 4 (BSC); Hacienda El Tulillo, 5 km. S Hipolito, 2; 17 mi. N and 8 mi. W
Saltillo, 5200 ft., 1; 3 mi. N and 5 mi. W La Rosa, 3600 ft., 1; 12 mi. N and 10
mi. E Parras, 5000 ft., 1; N foot Sierra Guadalupe, 9 mi. S and 5 mi. W General
Cepeda, 6200 ft., 1; N foot Sierra Guadalupe, 10 mi. S and 5 mi. W General
Cepeda, 6500 ft., 1.

Distribution.--Plains of northeastern Zacatecas, northward into extreme
southwestern Coahuila (see fig. 1).

Comparisons.--Compared with Cratogeomys castanops subnubilus, found to
the east, goldmani differs in: Body larger, tail and hind foot longer; color paler,
more rufous and less blackish; skull larger; zygomata more widely flaring; palate
larger; rostrum broader; nasals longer; maxillary teeth larger. Compared with
Cratogeomys castanops rubellus Nelson and Goldman, found to the southeast,
goldmani differs in: Body and skull smaller; zygomata less widely flaring;
palate shorter; rostrum narrower; maxillary teeth smaller.

Remarks.--Records of goldmani given here extend the known
range of this subspecies northward into southwestern Coahuila.
Specimens assigned to this subspecies from Coahuila compare favorably
[607]
with topotypes of goldmani (see tables 1 and 2) but are slightly
paler, and in this respect show some relationship to excelsus. The
ranges of these two subspecies however, are partly isolated by mountainous
country in southern Coahuila.

Specimens examined.--Total, 6, from: W foot Pico de Jimulco, 4600 ft., 1;
Valley Río Aguanaval, 1 mi. S Jimulco, 4; 1-1/2 mi. N Parras, 1.

Distribution.--Intermontane valleys and plains of southeastern Coahuila and
probably adjacent parts of Zacatecas, San Luis Potosí and Nuevo León (see
fig. 1).

Comparisons.--Cratogeomys castanops subnubilus needs close comparison
only with Cratogeomys castanops planifrons, found to the east and from which
subnubilus differs in: Body, hind foot and skull smaller; upper parts, in summer
pelage, paler, more rufous-buff and less dark russet; underparts paler, more
whitish and less blackish; hairs of hind foot reddish rather than blackish;
zygomata more widely flaring; palate shorter, especially in females; rostrum
broader, especially in females; nasals slightly smaller; squamosal breadth
greater; incisors narrower, especially in males; maxillary teeth smaller. From
Cratogeomys castanops rubellus Nelson and Goldman, found to the south in
San Luis Potosí, subnubilus differs in: Body, hind foot and all parts of skull
smaller; upper parts and underparts darker, more blackish and less rufous.

Specimens examined.--Total, 31, from: 1 mi. N Agua Nueva, 5500 ft., 1;
Domingo Cañon, Sierra Guadalupe, 6700 ft., 11 mi. S and 4 mi. W General
Cepeda, 1; Carneros, 6800 ft., 6 (BSC); 1 mi. S Carneros, 6000 ft., 4; 2 mi. W
San Miguel, 5500 ft., 3; 8 mi. N La Ventura, 6000 ft., 10; La Ventura, 5600
ft, 6 (BSC).

Distribution.--Elevated montane valleys of Sierra Madre Oriental of extreme
southeastern Coahuila, south and east into southwestern Nuevo León and Western
Tamaulipas (see fig. 1).

[608]

Specimens examined.--Total, 50, from: 4 mi. S and 6 mi. E Saltillo, 7500
ft, 7; 7 mi. S and 4 mi. E Bella Union, 7200 ft., 14; 12 mi. W San Antonio
de las Alazanas, 16; 12 mi. S and 2 mi. E Arteaga, 7500 ft., 11; 2 mi. E and 2
mi. N San Antonio de las Alazanas, 8700 ft, 2.

Transmitted August 23, 1954.

[End]

25-5679