Ticul Alvarez

“ In 1928 when Miller and Allen (Bull. U. S. Nat. Mus., 144) published their revisionary account of American bats of the genus Myotis, the black myotis, Myotis nigricans, was known no farther north than Chiapas and Campeche. Collections of mammals made in recent years for the Museum of Natural History of The University of Kansas include specimens of M. nigricans from eastern Mexico as far north as Tamaulipas. ”

“ Many times it has been said that the populations of wild animals were declining in México because the number of game wardens is too small to protect game in all parts of the country. In some ways this is true but it seems that the problem is really one of education. The people do not realize that the animals are part of nature and therefore have the same right to live that man has. Most people see only the bad side of the animals' activities and never consider the benefit that wild mammals provide for man. ”

“ In color, specimens from the barrier beach are pale as is oricolus, but the over-all color is reddish cinnamon rather than cinnamon buff. Concerning the juncture of the zygomatic plate with the jugal, 12 of the 13 specimens studied resemble annectens in this character and one resembles oricolus. The specimens from the barrier beach may themselves represent an unnamed subspecies; more material than now is available is needed, because most of the specimens are not fully adult. ”

“ Of the eight species that originally lived in Tamaulipas, the mule deer, brocket, and black bear never have been abundant there and now are in danger of extirpation. The pronghorn was also rare in the state and now has been extirpated as it has been in many other parts of México. The white-tailed deer, javalin, jaguar, and puma are still abundant in suitable habitats. The white-tailed deer is found almost everywhere in the state; in some areas it damages cornfields, and for this reason is killed by natives who eat the meat and sell the skins. The price of skins is low ”

“ Therefore, Osgood in 1909 in his revision of the genus Peromyscus reported only two subspecies of P. boylii from eastern México: P. b. levipes, and P. b. aztecus. Study of Osgood's and Thomas' material, along with recently collected specimens from the states of eastern México, leads me to conclude that P. aztecus and P. boylii are different species; that P. beatae is a valid subspecies different from P. b. levipes; and finally that specimens of P. boylii from Nuevo León and northwestern Tamaulipas pertain to an hitherto unnamed subspecies.
Peromyscus aztecus Saussure
1860. ”

“ Examination of more material and taking into consideration the relation between the interorbital constriction and the greatest length of skull, cause me here to refer those specimens to peragrus.
Hooper (1953:8) reported three young specimens from Rancho Pano Ayuctle as of the subspecies aquaticus, but study of two adults from the same locality reveals that this locality should be included within the geographic range of peragrus. ”

“ The two specimens from 1 mi. W Matatán were shot at late dusk as they foraged with other bats, presumably of the same species, low over water at the place where the Río San Antonio joins the larger Río Baluarte. The four individuals from 1⁄2 mi. S Concepción were captured in mist nets stretched across the Río de las Cañas at the Sinaloa-Nayarit border, and were taken shortly after dark at heights of three feet or less above the water. Our six specimens all are males. Five are in the reddish color phase and one is in the brownish phase. ”

“ The time is excellent for the establishment of the wildlife refuges [Pg 384] in Tamaulipas because large areas are still in Federal ownership and because a considerable number of animals remain. Other favorable factors are that roads are not yet good in the areas proposed for refuges, the human population is low, and agriculture consequently is not practiced. But, with the rapid increase in population in México, these favorable conditions will change in a few years and it will be almost impossible to establish the refuges then. ”

“ Mount Malinche (type locality of levipes) , and Thomas had not compared beatae with levipes. Xometla, on the east side of the Volcán de Orizaba, is approximately 56 miles east of the Tlaxcalan part of Mount Malinche and is situated where the Tropical Life-zone begins, whereas Mount Malinche is in the Austral Life-zone on the Mexican Plateau; the difference in habitat between the two places is great. Topotypes of levipes differ from two topotypes of beatae in the same fashion as do other specimens of levipes (from San Luis Potosí) from other specimens of beatae (from Veracruz) . ”

“ Additional material from this area is needed in order to make out the systematic position of these mice.
Because of the wide range of variation in some of its characters, P. b. ambiguus is difficult to diagnose. Nevertheless, its small external and cranial size, short anterior palatine foramina, and bright color seem to separate it from other subspecies of P. boylii in the eastern part of the range of the species. These differences are most conspicuous when specimens from the northernmost part of the range of levipes are compared with specimens of ambiguus. ”

“ When one deer in a night can destroy part of the corn, and in some areas not only one deer but several invade a field, and when one considers that besides deer there are rabbits, squirrels, raccoons, and coati, to name only some animals that feed on the corn, we find that the small cornfield at the end of the season may not contain any corn to harvest. ”

“ It is understandable, therefore, that the natives kill the animals. In this way they protect their cultivated fields, obtain food and sometimes money for the skins. Many natives, however, destroy the wildlife only for pleasure or to obtain money for skins and meat, which sometimes is sold to restaurants.
Probably the best solution for the problem of conservation of wild animals is the establishment of wildlife refuges. In Tamaulipas, at least three refuges are needed in order to preserve the mammalian wildlife. ”

“ Comparison of 10 specimens of B. a. flavus from Coahuila and Texas with two of B. a. astutus (Distrito Federal, 1; Las Vigas, Veracruz, 1) from central México reveals that the skulls do not differ qualitatively and that the skull of flavus tends to be smaller and relatively wider, but that there is overlap in size. In all flavus that I measured and in the two adults of astutus the tail is shorter than the head and body. The only real difference is the color; ringtails from Texas are deep fulvous instead of grayish as is [Pg 457] astutus from the Distrito Federal and Veracruz. ”

“ The Río Grande, as was pointed out by R. H. Baker (1956:146) , has low banks, is relatively shallow, and does not form an effective barrier for most mammals. For only two species, insofar as I know, has the Río Grande constituted a barrier. Cratogeomys castanops has not entered southeastern Texas from México, and Spermophilus spilosoma has not entered México from southeastern Texas except on the coastal barrier beach. Alvarez (1962:124) postulated that the beach was the route by which S. spilosoma arrived at La Pesca where the barrier beach meets the mainland. ”

“ ACCOUNTS OF SPECIES AND SUBSPECIES Didelphis marsupialis
Opossum
The opossum occurs throughout Tamaulipas but is commonest in the south, especially in the areas of tropical forest and along water courses. Most of the specimens examined were caught in steel traps baited with remains of small animals (mostly mammals and birds, but one trap was baited with the head of a black bass) . At Villa Mainero five individuals were caught in one night in five of seven traps scented with spilogale musk. ”

“ Considering that México has no professional trappers and that commerce in skins of wild animals is illegal, it is felt that the number of skins found in the tanner's shop indicated a relative large population of game mammals.
The number of species of small game also is large. Some species are killed by natives for food, but most are killed in order to protect the cultivated crops, which are injured mainly by rabbits and squirrels. ”

“ One specimen from nine miles southwest of Tula was caught in an outcrop of rocks and two others were taken among bushes on the desert. A female on October 10 carried 4 embryos 2 mm. in crown-rump length.
Specimens of P. melanophrys here listed are the first to be reported from Tamaulipas. They are assigned to the subspecies consobrinus on the basis of dark color and because their size closely corresponds to that of the holotype. The specimen from the vicinity of Palmillas and one from Miquihuana (56408) are larger than the others and grayish. ”

“ With the establishment of these three refuges and with good management the fauna of Tamaulipas could be saved from extinction, would provide some recreation for sportsmen, and especially for the people in general who wish to study, photograph, or merely observe the native animal life. ”

“ Nycticeius humeralis has the same distributional pattern in Tamaulipas as has Lasiurus borealis in that both are represented there by two subspecies, one known only from Matamoros and the other occurring in the rest of the state. Bats of this species (N. h. mexicanus) from Ciudad Victoria and some from the Sierra de Tamaulipas were shot in flight in evening; others from the last-mentioned locality were taken in mist nets. Lactating females (22 specimens) were collected in June and July. ”

“ From Tamaulipas, the northeasternmost state in the Mexican Republic, 146 kinds of mammals, belonging to 72 genera, are here reported. Mammals that are strictly marine in habit are not included. The state is crossed in its middle by the Tropic of Cancer. Elevations vary from sea level on the Golfo de México to more than 2700 meters in the Sierra Madre Oriental; most of the state is below 300 meters in elevation. Its area is 79,602 square kilometers (30,732 square miles) . ”

“ The Montane route was used by mammals of boreal affinities (Microtus and Neotoma) , that moved into Tamaulipas from the north; also in this category are bats of the family Vespertilionidae. For movement from south to north, the route was used by several species native to México, for example, Cratogeomys castanops. The [Pg 378] seaward slope of the montane area has enabled some tropical mammals to move farther north than they have done at higher and lower elevations. Philander opossum seems to be an example. ”

“ In this official program some lectures in conservation are needed with reference to the animal life. I know that some education now is given to people with respect to conservation of the water, soil, and forest, but gather that there is little that covers also conservation of animals. ”

“ Several came from the Great Plains, and a few came from the eastern part of the United States. Also, a few mammals that may have originated in the Tamaulipan Province moved northwards. Some of these, according to Dice (1937:267) were Liomys irroratus texensis, Peromyscus leucopus texensis, and Lepus californicus merriami. Other mammals thought to have moved north by this route are Didelphis marsupialis, Dasypus novemcinctus, Oryzomys palustris, Nasua narica, and Tayassu tajacu. Some mammals that passed through Tamaulipas into Texas have extended their geographic ranges far north of Texas. ”

“ But the exact line between this Province and the Tamaulipan Province to the north is difficult to draw. The northern boundary of the Veracruzian Province is the line between the Nearctic and Neotropical regions in eastern México.
Vegetation of most of the Veracruzian Biotic Province is Tropical Deciduous Forest. This Forest is made up of Tabebuia, Ipomea, Bombax, and Conzattia, along with some Ceiba, Bursera, and Psidium.
[Pg 376]
The mammalia fauna of the Veracruzian Biotic Province is tropical in nature. ”