Distribution.—This species is known only from elevations between 1500 and 1700 meters on the Atlantic slopes of the Chiapan Highlands; it is to be expected in cloud forests on the northern slopes of the Sierra de Cuchumatanes in Guatemala.
Specimens examined.—Mexico: Chiapas: 15 km. N of Pueblo Nuevo Solistahuacán, UMMZ 123325 (4); 16.5 km. N of Pueblo Nuevo Solistahuacán, UMMZ 123322 (10); 18 km. N of Pueblo Nuevo Solistahuacán, UMMZ 121395-9, 123324 (8), 123326 (5); 18.6 km. N of Pueblo Nuevo Solistahuacán, UMMZ 123323 (4); 5.6 km. S of Rayón Mescalapa, KU 58062, 58200 (tadpoles); 6.2 km. S of Rayón Mescalapa, KU 58063-74, 58199 (tadpole), 58234-8, 59936 (skeleton).
Diagnosis.—Diameter of tympanum less than one-half diameter of eye; internarial region flat; 3-7 vomerine teeth; toes one-half webbed; no white spot below eye; no lateral white stripe; in life dorsum green; groin and thighs having bright red flash-colors.
Description.—The following description is based on UMMZ 119603 from 6 kilometers south of Vista Hermosa, Oaxaca, México (Pl. 18). Adult male having a snout-vent length of 30.0 mm.; tibia length, 14.6 mm.; tibia length/snout-vent length, 48.7 per cent; foot length, 12.3 mm.; head length, 9.2 mm.; head length/snout-vent length, 30.7 per cent; head width, 9.3 mm.; head width/snout-vent length, 31.0 per cent; diameter of eye, 3.2 mm.; diameter of tympanum, 1.3 mm.; tympanum/eye, 40.6 per cent. Snout in lateral profile square, and in dorsal profile rounded; canthus pronounced; loreal region slightly concave; lips moderately flaring; top of head flat; nostrils protuberant; internarial distance, 2.8 mm.; internarial region flat; interorbital distance, 3.3 mm., much broader than width of eyelid, 2.8 mm. A heavy dermal fold from posterior corner of eye above tympanum to insertion of forelimb, covering upper edge of tympanum; tympanum elliptical, its greatest diameter equal to its distance from eye. Forearm moderately robust having distinct dermal fold on wrist; pollex moderately enlarged without nuptial spines; second and fourth fingers equal in length; subarticular tubercles round, none is bifid; discs on fingers moderate in size, that on third finger slightly larger than tympanum; no web between first and second fingers; vestige of web between other fingers. Heels overlap when hind limbs adpressed; tibiotarsal articulation extends to anterior corner of eye; no tarsal fold; inner metatarsal tubercle large, flat, and elliptical; outer metatarsal tubercle near inner one and triangular in shape; subarticular tubercles round; length of digits from shortest to longest 1-2-5-3-4; third toe webbed to proximal end of penultimate phalanx; fourth toe webbed to distal part of antepenultimate phalanx; fifth toe webbed to middle of penultimate phalanx; discs on toes smaller than on fingers. Anal opening directed posteriorly at upper edge of thighs; no anal flap; pair of large tubercles below anal opening; small tubercles ventral and lateral to these. Skin of dorsum and ventral surfaces of limbs smooth; that of throat and belly granular. Ventrolateral glands noticeably thickened, extending from axilla nearly to groin and only narrowly separated midventrally on chest; skin of anterior part of chin thickened and glandular. Tongue cordiform, shallowly notched behind and only slightly free posteriorly; vomerine teeth 0-3, situated on rounded elevations between somewhat larger, round inner nares; openings to vocal sac large, one situated along posterior margin of each mandibular ramus.
Dorsal ground-color of head, body, and limbs dull brown with dark brown reticulations on head and body and dark brown transverse bands or spots on limbs; first and second fingers cream color; third and fourth fingers dull tan; anterior surfaces of thighs pale brown; posterior surfaces of thighs cream color with heavy suffusion of brown; dorsal surfaces of tarsi and third, fourth, and fifth toes dull brown with dark brown spots; first and second toes creamy white; webbing on foot brown; axilla and groin cream color; flanks brown; no white stripes on edge of upper lip or on flank; faint, barely discernible tan streak above anal opening; faint creamy tan line on ventrolateral edges of tarsi; throat, belly, ventral surfaces of limbs, inner edges of tarsi, and first toes cream color; outer ventral surfaces of tarsi and other toes brown; chest and throat spotted with brown; ventrolateral and chin glands orange-brown.
In life the dorsum was uniform green (Cosse Green) becoming paler green (Bright Green-Yellow) on flanks, later changing to paler green (Javel Green) on dorsum with irregular darker green (Lettuce Green) markings and greenish yellow (Green-Yellow) on flanks; anterior and posterior surfaces of thighs, ventral surfaces of shanks, anterior surfaces of tarsi, and upper proximal surfaces of first, second, and third toes red (Coral Red); venter pale creamy yellow (Sulfur Yellow); iris pale golden color (Aniline Yellow).
Variation.—Of 13 specimens, six have a cordiform tongue; the others have an emarginate tongue. Five specimens have round subarticular tubercles beneath the fourth fingers; six specimens have a bifid tubercle on one hand, and two specimens have bifid tubercles on both hands. A round gland is present on the chin of all specimens; in some the gland is barely visible, but in others it is large and distinct. In two specimens the ventrolateral glands are weakly developed; in the others the glands are well developed and orange-tan. The white anal stripe varies from a thin line to a series of white flecks. Dark brown or black flecks are present on the throat, chest, and flanks of all specimens. In some the flecks are small and widely scattered; in others the flecks are larger and more numerous. All specimens were pale green above when calling at night; later they changed to dull green with darker green reticulations. The flash-colors on the thighs and in the groin vary from red to orange-red or brownish red.
Description of tadpole.—The following description is based on KU 71716 from Vista Hermosa, Oaxaca, México (Figs. 5C and 6G). Hind limbs small; total length, 39.6 mm.; body length, 11.8 mm.; body length/total length, 29.8 per cent. Body moderately depressed, only slightly wider than deep, in dorsal profile ovoid, widest just posterior to eyes; in lateral profile snout rounded; mouth directed ventrally; eyes small, directed dorsolaterally; nostrils barely protuberant, directed anteriorly, somewhat closer to eye than snout; spiracle sinistral and posteroventrad to eye; anal tube dextral. Tail long and slender; caudal fin low and rounded posteriorly; depth of caudal musculature about one-half greatest depth of caudal fin; musculature not extending to tip of tail.
Mouth large; thin fleshy lips greatly expanded and forming large funnel-shaped disc; width of mouth about two-thirds greatest width of body; outer edge of lips having one row of small papillae; inner surface of mouth smooth; scattered large papillae forming one nearly complete row around teeth; other papillae laterally; one large papilla just above each end of first lower tooth-row; beaks moderately developed bearing long, pointed denticulations; no lateral projections on upper beak; tooth-rows 3⁄3, all short; second and third upper rows subequal in length; first upper row shorter; first lower row equal in length to second and third upper rows; second lower row slightly shorter; third lower row shortest.
Body creamy gray with dark brown flecks above and below; mouth colored like body; caudal musculature creamy tan; caudal fin transparent; dark brown streak on anterior third of caudal musculature; rest of tail and all of caudal fin, except anterior two-thirds of ventral fin, heavily flecked with brown; iris silvery bronze color in life.
Variation.—The only other known tadpole, which was collected with the individual described above, differs in having only two upper tooth-rows. The first upper tooth-row seems not to have developed.
Comparisons.—From P. schmidtorum chamulae and P. s. schmidtorum, P. ignicolor differs as follows: Tympanum smaller; snout more nearly square; less webbing on toes; internarial region flat instead of depressed; white lateral stripes lacking.
Ptychohyla ignicolor and several small and moderate sized hylids are sympatric. From P. ignicolor these hylids can be distinguished as follows: Hyla dendroscarta has a round snout and yellow dorsum; Hyla erythromma has a round snout, green dorsum, white flanks, and a red eye; Hyla hazelae has a tarsal fold, green dorsum, and a black line on the canthus; and Ptychohyla leonhardschultzei has a tarsal fold, brown dorsum, black and white flanks, and horny nuptial spines in breeding males.
Life History.—At Vista Hermosa, Oaxaca, males were calling on vegetation above small streams on March 30, 1959, and on June 28, 1962; males were found on vegetation overhanging a stream 6 kilometers south of Vista Hermosa on June 27 and July 3, 1962. The call consists of a series of short notes, three to thirteen notes per series, sounding like "raa-raa-raa." The duration of each note is about .08 of a second and has a rate of 123 to 129 pulses per second. The dominant frequency of notes in short series is about 2100 cycles per second, whereas the dominant frequency of notes in long series is about 3150 cycles per second (Pl. 11E).
On June 28, 1962, two tadpoles of this species were found in a quiet pool in a spring-fed rivulet at Vista Hermosa, Oaxaca. Females are unknown.
Remarks.—The absence of a tarsal fold and of nuptial spines in breeding males, the nature of the breeding call, and the form of tadpole are characters that place Ptychohyla ignicolor in the P. schmidtorum-group.
Distribution.—This species is known from only two localities at elevations of 1500 and 1850 meters in the cloud forest on the northern (Atlantic) slopes of the Sierra Madre Oriental in northern Oaxaca.
Specimens examined.—Mexico: Oaxaca: Vista Hermosa, KU 71334, 71716 (tadpoles), UMMZ 119602; 6 km. S of Vista Hermosa, KU 71335-42, 71343 (skeleton), UMMZ 119603, 123327 (2).
The distribution of species of Ptychohyla reflects the distribution of cloud forest in southern México and northern Central America. The frogs are restricted to mountainous areas, usually at elevations higher than 1000 meters above sea level. Ptychohyla does not range to great heights in the mountains, where west of the Isthmus of Tehuantepec the mountain streams are inhabited by frogs of the Hyla bistincta group, and in Chiapas and Guatemala by species of Plectrohyla.
Frogs of the Ptychohyla euthysanota group have a greater combined geographic range than the species comprising the Ptychohyla schmidtorum group (Fig. 7). No two species in the same group are sympatric, but members of different groups are sympatric in at least parts of their ranges. Apparently P. leonhardschultzei ranges around the southern edge of the Mexican Highlands, where the species occurs on both Atlantic and Pacific slopes; as can be seen from the distribution map, there are many gaps in the known range of this species. The range of P. euthysanota euthysanota is along the Pacific slopes of the Sierra Madre in Chiapas, Guatemala, and El Salvador, whereas that of P. euthysanota macrotympanum is along the southern interior slopes of the Central Highlands of Chiapas and the Sierra de Cuchumatanes in Guatemala. Ptychohyla spinipollex occurs on the wet Atlantic slopes of the Guatemalan and Honduranean Highlands; the range of the species in Honduras is poorly known.
Fig. 7. Map showing locality records for the species and subspecies of Ptychohyla.
The frogs of the Ptychohyla schmidtorum group have more restricted geographic ranges than members of the former group. Ptychohyla schmidtorum schmidtorum occurs on the Pacific slopes of the Sierra Madre in Chiapas and Guatemala, where it occurs with P. euthysanota euthysanota; P. schmidtorum chamulae is known from only two localities on the Atlantic slopes of the Central Highlands of Chiapas, where it occurs close to, but as now known not with, P. euthysanota macrotympanum. On the Atlantic slopes of the Sierra Madre Oriental in northern Oaxaca P. ignicolor occurs with P. leonhardschultzei.
In the Sierra de los Tuxtlas in southern Veracruz and in the cloud forests along the eastern slopes of the Sierra Madre Oriental northward to Nuevo León, Hyla miotympanum seems to be the ecological replacement of Ptychohyla. On the Pacific slopes north of Guerrero, México, humid forests in which there are cascading mountain streams are absent; consequently, no Ptychohyla are known from that region. In the mountains of El Salvador Ptychohyla euthysanota euthysanota occurs sympatrically with another small stream-breeding hylid, Hyla salvadorensis. To the south of Honduras the highlands diminish into the lowlands of Nicaragua, where habitat suitable for Ptychohyla apparently does not exist. In the mountains of Costa Rica and Panamá, the habitats occupied by Ptychohyla in northern Central America are filled by a variety of stream-breeding Hyla, such as Hyla legleri, H. rivularis, H. rufioculis, H. alleei, and H. uranochroa.
Although members of the genus Ptychohyla occur in the southern part of the Mexican Highlands to the west of the Isthmus of Tehuantepec, the greater distribution and differentiation in the genus is in the Chiapan-Guatemalan Highlands. In this respect Ptychohyla is a counterpart of Plectrohyla.
Frogs of the genus Ptychohyla are ecologically associated with mountain streams at elevations between 650 and 2200 meters; in the geographic region where these frogs occur the vegetation between those elevations consists of cloud forest or pine-oak forest. In some places the frogs have been found in a mixture of oak and semi-deciduous scrub forest. At Vista Hermosa, Oaxaca, P. leonhardschultzei and P. ignicolor were found in cloud forest, whereas at Agua del Obispo, Guerrero, the former species was found in pine-oak forest. Ptychohyla schmidtorum is known only from cloud forest; P. euthysanota euthysanota and P. spinipollex generally are found in cloud forest, but in some places they live in pine-oak forest. Ptychohyla euthysanota macrotympanum has been found in pine-oak forest and in a mixture of oak and semi-deciduous scrub forest. With the possible exception of the members of the Ptychohyla schmidtorum group, which has been found only in cloud forest, it seems as though the type of vegetation is not the controlling factor in the ecological distribution of these frogs.
Ptychohyla has been found only where there are clear, cascading streams overhung by vegetation, on which adults and young perch at night, or even by day. The presence of these streams, in which the tadpoles live, seems to be an important factor in the distribution of Ptychohyla. As has been shown previously, the tadpoles of Ptychohyla are adapted for existence in torrential streams, where the water is cool, and the amount of oxygen is high. Clearly these tadpoles are unsuited for life in ponds or sluggish streams in the lowlands, where the temperature of the water is high, a layer of silt on the bottom is deep, and the amount of oxygen is low. The tadpoles cling to rocks on the bottom of the streams; there they move slowly across the rocks, apparently feeding on the thin covering of algae. Tadpoles were not observed on rocks having a thick covering of algae or moss. The tadpoles were observed to swim against the current in torrential streams, in which no fishes were found. Therefore, it seems as though the presence of the stream-habitat for the tadpoles is a significant factor in the ecological distribution of the species of Ptychohyla.
At localities where two species of Ptychohyla occur sympatrically (P. ignicolor and P. leonhardschultzei at Vista Hermosa, Oaxaca, and P. euthysanota euthysanota and P. schmidtorum schmidtorum at Finca La Paz, Depto. San Marcos, Guatemala) effort was made to determine what, if any, ecological interspecific relationships existed. Although adults of the sympatric species were found on adjacent leaves or branches of bushes overhanging the streams at both localities, segregation at the time of breeding seems to be maintained by the notably different breeding calls in sympatric species (see discussion of breeding calls). Thus, as has been shown by Blair (1956), Fouquette (1960), and others working on a variety of pond-breeding frogs and toads, the breeding call in Ptychohyla acts as an important reproductive isolating mechanism.
At no locality were Ptychohyla and associated species of hylids found so abundantly as were species of pond-breeding hylids in the lowlands. Apparently reproductive activity is not concentrated in a short breeding season, and it is highly doubtful if the populations of these frogs are as large as those of the lowland pond-breeders. The continual humid conditions and abundance of insect food throughout the year in the cloud forest are perhaps indicative of little interspecific competition among adults of Ptychohyla and other sympatric hylids.
At Finca La Paz, Guatemala, tadpoles of two species of Ptychohyla were ecologically segregated. The tadpoles of P. euthysanota euthysanota were found in riffles in the streams, whereas those of P. schmidtorum schmidtorum were found in slower water, chiefly in small pools in the streams. At Vista Hermosa, Oaxaca, tadpoles of P. leonhardschultzei were found in riffles, and tadpoles of the sympatric P. ignicolor were found in a small pool in a stream. Similar ecological relationships were observed for several species of Costa Rican hylids. Throughout the range of Ptychohyla east of the Isthmus of Tehuantepec, members of the genus occur with species of Plectrohyla, all of which are larger than Ptychohyla, and all of which have tadpoles that live in torrential streams. Tadpoles of Ptychohyla spinipollex have been found in streams inhabited by the tadpoles of Plectrohyla guatemalensis and P. quecchi; tadpoles of Ptychohyla euthysanota euthysanota and P. schmidtorum schmidtorum were found in streams inhabited by tadpoles of Plectrohyla guatemalensis, P. matudai, and P. sagorum. In some streams great numbers of tadpoles occur. The habitat is rather restricted, and the food supply is limited. Consequently, interspecific competition among the various species of hylids whose tadpoles live in the torrential streams probably is highest during the larval stage. Unfortunately, this aspect of salientian population ecology has received no intensive study.
Since the cloud forests inhabited by Ptychohyla are daily bathed in clouds and have a fairly evenly distributed rainfall throughout the year, the frogs living in these forests are active throughout the year. At least some of the species evidently have a long breeding season, for I found calling males of P. leonhardschultzei in February, March, and August, and found tadpoles in February, March, June, and August. Tadpoles of the various species have been obtained throughout much of the year, as follows: P. euthysanota euthysanota, February, March, May, and July; P. euthysanota macrotympanum, March, June, and August; P. spinipollex, February, March, April, June, July, and August; P. schmidtorum schmidtorum, March, May, June, July, and August; P. schmidtorum chamulae, June and August; P. ignicolor, June. I suspect that this temporal distribution more accurately reflects the seasonal activities of collectors than of the frogs.
Calling frogs usually are on vegetation adjacent to or overhanging streams; some calling males of P. spinipollex were on rocks in or by streams. Clasping pairs of P. euthysanota and P. schmidtorum were observed on vegetation by streams. Despite intensive search, no eggs were found. It is doubtful if Ptychohyla deposit eggs on vegetation overhanging streams, as do centrolenids and Phyllomedusa, for egg-clutches of these frogs are easily found. Possibly the eggs are laid separately on vegetation above the stream, in which case they could be overlooked easily. In streams where Ptychohyla and other hylid tadpoles occur, empty egg capsules have been found on the lee sides of rocks, but there is no way to determine which species laid the eggs.
Numbers of eggs were counted in gravid females; the largest eggs have diameters ranging from 2.5 to 3.0 mm. The smaller species, comprising the Ptychohyla schmidtorum group, have fewer eggs than do the larger species. Numbers of eggs found in females of the various species are: P. euthysanota euthysanota, 108; P. euthysanota macrotympanum, 136, 160; P. leonhardschultzei, 141; P. spinipollex, 119, 134, 143; P. schmidtorum schmidtorum, 59, 61, 90; P. schmidtorum chamulae, 60, 71, 89.
Duration of the larval stage is unknown. Metamorphosing young have been found from May through August. From two to six completely metamorphosed young are available for each of the species, except for P. ignicolor of which none is available. The smallest young frog is a P. euthysanota having a snout-vent length of 14.2 mm.; the largest young frog is a P. schmidtorum schmidtorum having a snout-vent length of 17.0 mm.
The preceding data on morphology, life histories, and behavior form the basis for the following interpretation of the phylogeny of Ptychohyla. Additional data are needed to support some of the ideas discussed below; many of the data that are available for Ptychohyla are lacking for other, possibly related, hylids. The family Hylidae is composed of several hundred species, and most of the species are poorly known. Consequently, any attempt to place Ptychohyla in the over-all scheme of hylid phylogeny would be premature at this time. But, as between the five species of two species-groups here recognized as constituting the genus Ptychohyla, some estimate of relationships can be made. First, it is necessary to determine the validity of the genus itself.
As stated in the diagnosis of the genus, the only character that sets this group of species apart from other hylids is the presence of ventrolateral glands in the breeding males. To many systematists the thought of being able to identify to genus only breeding males is sufficiently disturbing to cause them to view with disfavor the recognition of the genus. Nonetheless, the question is raised: Do the five species herein placed in the genus Ptychohyla constitute a natural assemblage? If the genus is considered to be more than a category of convenience, that is to say, a group of related species having a common origin, the primary problem is to determine whether or not the five species form a phylogenetic unit.
The species of Ptychohyla are divided into two groups on the basis of external morphology, breeding calls, and tadpoles. The Ptychohyla euthysanota group seems to be a natural group composed of three species, all of which are more closely related to one another than to any other hylid. Likewise, the species comprising the Ptychohyla schmidtorum group seem to represent a natural unit. If the presence of ventrolateral glands in breeding males is ignored, a student of salientian systematics might derive the Ptychohyla euthysanota group from a hylid stock containing Hyla miotympanum and Hyla mixomaculata. Likewise, Ptychohyla schmidtorum could be placed with Hyla uranochroa and related species in Costa Rica. Nonetheless, the fact remains that all of the species assigned to the genus Ptychohyla have ventrolateral glands in the breeding males; furthermore, ventrolateral glands are unknown in other hylids. If the P. schmidtorum group and the P. euthysanota group each evolved from separate hylid stocks, then the ventrolateral glands must have developed independently in both groups. That ventrolateral glands developed independently in five species of frogs in southern México and northern Central America and not in any of the other approximately 500 species of hylids in the world is untenable. It is more logical to assume that the development of the glands took place only once in a stock of hylids that gave rise to the five species herein recognized as members of the genus Ptychohyla.
The affinities of Ptychohyla apparently are not with any of the other groups that have been generically separated from Hyla. Of the daughter genera in Middle America only Plectrohyla has stream-adapted tadpoles, but these large frogs are not closely related to Ptychohyla. Stuart (1954:169) suggested that certain montane species of Hyla in lower Central America and Hyla salvadorensis in El Salvador may be related to Ptychohyla or even congeneric. I have had experience with most of these species in the field and believe that Stuart was correct in his suggestion of relationships. The species concerned are four red-eyed stream-breeding Hyla in Costa Rica—H. alleei, H. legleri, H. rufioculis, and H. uranochroa, plus Hyla salvadorensis in the mountains of El Salvador. Morphologically all of the species are similar; Hyla uranochroa, H. legleri, and H. rufioculis have a lateral white stripe that is expanded to form a spot beneath the eye, as in Ptychohyla schmidtorum. The tadpoles of Hyla rufioculis and H. uranochroa have large funnel-shaped mouths and long slender tails like those of Ptychohyla schmidtorum. Lips of the tadpoles of H. legleri and H. salvadorensis are folded laterally, in this respect resembling those of the Ptychohyla euthysanota group. I do not know the tadpoles and the breeding call of Hyla alleei. The breeding calls of Hyla rufioculis and H. uranochroa consist of high melodious notes; the calls of H. legleri and H. salvadorensis consist of series of short notes that have the general characteristics of the call of Ptychohyla schmidtorum. Affinities of the genus Ptychohyla seem to me to be with the red-eyed species forming the Hyla uranochroa group in Costa Rica. All of the species in the Hyla uranochroa group have large frontoparietal fontanelles, rather small ethmoids, and small nasals that are not in contact with one another or with the ethmoid. Some species have a complete quadratojugal-maxillary arch; others do not. Assuming that the parental stock that gave rise both to the Hyla uranochroa group and to Ptychohyla was widespread in Central America at a time of cooler, more humid conditions, it is possible that with subsequent warming temperatures and seasonal rainfall in the lowlands the parental stock was restricted to the Costa Rican highlands, where the Hyla uranochroa group developed, and to the Chiapas-Guatemala highlands, where Ptychohyla evolved.
Ptychohyla schmidtorum is thought to resemble more closely the parental stock of the genus than does any other species of Ptychohyla now extant. This parental stock is discussed above in the account of the generic relationships. Ptychohyla schmidtorum has a red eye, white lateral stripe, frontoparietal fontanelle, funnel-shaped mouth in tadpoles, and lacks nuptial spines; in all of these characters it resembles members of the Hyla uranochroa group. Probably during times of glaciation during the Pleistocene, when climates in México and Central America were depressed, the Ptychohyla stock was more widespread than it is now. Subsequent elevation of climatic zones during interglacial periods would have isolated populations as they are today in regions of cloud forests. Thus, through geographic isolation populations could have differentiated and evolved into the present species. Climatic fluctuation in the Pleistocene must have been of sufficient magnitude to permit the spread of cool, moist forests containing Ptychohyla across the Isthmus of Tehuantepec into the mountains of Oaxaca.
Because of its small nuptial spines, small triangular vomers, coloration, and absence of a rostral keel, Ptychohyla euthysanota, more than any of the other species in the P. euthysanota group, resembles P. schmidtorum. At the present time P. euthysanota and P. schmidtorum are sympatric.
As I have mentioned previously, ecological segregation and interspecific competition probably is highly developed in the tadpoles of Ptychohyla. If this ecological segregation resulted from intraspecific competition in a stock of Ptychohyla, possibly P. euthysanota and P. schmidtorum differentiated sympatrically in this way. Specific identity is maintained, at least in part, by different breeding calls in males.
Ptychohyla spinipollex and P. leonhardschultzei seem to be more closely related to one another than either is to P. euthysanota. Probably a stock of P. euthysanota was isolated on the Atlantic slopes of northern Central America from P. euthysanota on the southern slopes. The frogs on the Atlantic slopes differentiated and spread into the mountains of Oaxaca, where through isolation by the barrier of the Isthmus of Tehuantepec they developed into P. leonhardschultzei, while the stock on the northern slopes of Central America evolved into P. spinipollex. Subsequent to the differentiation of P. leonhardschultzei and P. spinipollex from P. euthysanota and during a time of cooler more equable climate than exists now, P. euthysanota and P. schmidtorum invaded the Central Highlands of Chiapas. Subsequent climatic changes isolated populations of each in the Central Highlands, where P. euthysanota macrotympanum and P. schmidtorum chamulae evolved. Ptychohyla ignicolor probably represents stock of P. schmidtorum that crossed the Isthmus of Tehuantepec and became isolated in Oaxaca on the western side of the isthmus.
Ptychohyla euthysanota euthysanota (KU 58008). × 2.
Ptychohyla euthysanota macrotympanum (KU 58049). × 2.
Ptychohyla leonhardschultzei (KU 64117). × 2.
Ptychohyla spinipollex (KU 58054). × 2.
Ptychohyla schmidtorum schmidtorum (KU 58043). × 2.
Ptychohyla schmidtorum chamulae (KU 58069). × 2.
Ptychohyla ignicolor (UMMZ 119603). × 2.
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1949. New or unusual Mexican amphibians. Amer. Mus. Novitates,
1437:1-21, December 7.
Transmitted December 27, 1962.
MUSEUM OF NATURAL HISTORY
Institutional libraries interested in publications exchange may obtain this series by addressing the Exchange Librarian, University of Kansas Library, Lawrence, Kansas. Copies for individuals, persons working in a particular field of study, may be obtained by addressing instead the Museum of Natural History, University of Kansas, Lawrence, Kansas. There is no provision for sale of this series by the University Library, which meets institutional requests, or by the Museum of Natural History, which meets the requests of individuals. Nevertheless, when individuals request copies from the Museum, 25 cents should be included, for each separate number that is 100 pages or more in length, for the purpose of defraying the costs of wrapping and mailing.
* An asterisk designates those numbers of which the Museum's supply (not the Library's supply) is exhausted. Numbers published to date, in this series, are as follows:
| Vol. 1. | Nos. 1-26 and index. Pp. 1-638, 1946-1950. | ||
| *Vol. 2. | (Complete) Mammals of Washington. By Walter W. Dalquest. Pp. 1-444, 140 figures in text. April 9, 1948. | ||
| Vol. 3. | *1. | The avifauna of Micronesia, its origin, evolution, and distribution. By Rollin H. Baker. Pp. 1-359, 16 figures in text. June 12, 1951. | |
| *2. | A quantitative study of the nocturnal migration of birds. By George H. Lowery, Jr. Pp. 361-472, 47 figures in text. June 29, 1951. | ||
| 3. | Phylogeny of the waxwings and allied birds. By M. Dale Arvey. Pp. 473-530, 49 figures in text, 13 tables. October 10, 1951. | ||
| *4. | Birds from the state of Veracruz, Mexico. By George H. Lowery, Jr., and Walter W. Dalquest. Pp. 531-649, 7 figures in text, 2 tables. October 10, 1951. | ||
| Index. Pp. 651-681. | |||
| *Vol. 4. | (Complete) American weasels. By E. Raymond Hall. Pp. 1-466, 41 plates, 31 figures in text. December 27, 1951. | ||
| Vol. 5. | Nos. 1-37 and index. Pp. 1-676, 1951-1953. | ||
| *Vol. 6. | (Complete) Mammals of Utah, taxonomy and distribution. By Stephen D. Durrant. Pp. 1-549, 91 figures in text, 30 tables. August 10, 1952. | ||
| Vol. 7. | Nos. 1-15 and index. Pp. 1-651, 1952-1955. | ||
| Vol. 8. | Nos. 1-10 and index. Pp. 1-675, 1954-1956. | ||
| Vol. 9. | *1. | Speciation of the wandering shrew. By James S. Findley. Pp. 1-68, 18 figures in text. December 10, 1955. | |
| 2. | Additional records and extension of ranges of mammals from Utah. By Stephen D. Durrant, M. Raymond Lee, and Richard M. Hansen. Pp. 69-80. December 10, 1955. | ||
| 3. | A new long-eared myotis (Myotis evotis) from northeastern Mexico. By Rollin H. Baker and Howard J. Stains. Pp. 81-84. December 10, 1955. | ||
| 4. | Subspeciation in the meadow mouse, Microtus pennsylvanicus, in Wyoming. By Sydney Anderson. Pp. 85-104, 2 figures in text. May 10, 1956. | ||
| 5. | The condylarth genus Ellipsodon. By Robert W. Wilson. Pp. 105-116, 6 figures in text. May 19, 1956. | ||
| 6. | Additional remains of the multituberculate genus Eucosmodon. By Robert W. Wilson. Pp. 117-123, 10 figures in text. May 19, 1956. | ||
| 7. | Mammals of Coahulia, Mexico. By Rollin H. Baker. Pp. 125-335, 75 figures in text. June 15, 1956. | ||
| 8. | Comments on the taxonomic status of Apodemus peninsulae, with description of a new subspecies from North China. By J. Knox Jones, Jr. Pp. 337-346, 1 figure in text, 1 table. August 15, 1956. | ||
| 9. | Extensions of known ranges of Mexican bats. By Sydney Anderson. Pp. 347-351. August 15, 1956. | ||
| 10. | A new bat (Genus Leptonycteris) from Coahulia. By Howard J. Stains. Pp. 353-356. January 21, 1957. | ||
| 11. | A new species of pocket gopher (Genus Pappogeomys) from Jalisco, Mexico. By Robert J. Russell. Pp. 357-361. January 21, 1957. | ||
| 12. | Geographic variation in the pocket gopher, Thomomys bottae, in Colorado. By Phillip M. Youngman. Pp. 363-387, 7 figures in text. February 21, 1958. | ||
| 13. | New bog lemming (genus Synaptomys) from Nebraska. By J. Knox Jones, Jr. Pp. 385-388. May 12, 1958. | ||
| 14. | Pleistocene bats from San Josecito Cave, Nuevo León, México. By J. Knox Jones, Jr. Pp. 389-396. December 19, 1958. | ||
| 15. | New subspecies of the rodent Baiomys from Central America. By Robert L. Packard. Pp. 397-404. December 19, 1958. | ||
| 16. | Mammals of the Grand Mesa, Colorado. By Sydney Anderson. Pp. 405-414, 1 figure in text, May 20, 1959. | ||
| 17. | Distribution, variation, and relationships of the montane vole, Microtus montanus. By Sydney Anderson. Pp. 415-511, 12 figures in text, 2 tables. August 1, 1959. | ||
| 18. | Conspecificity of two pocket mice, Perognathus goldmani and P. artus. By E. Raymond Hall and Marilyn Bailey Ogilvie. Pp. 513-518, 1 map. January 14 1960. | ||
| 19. | Records of harvest mice, Reithrodontomys, from Central America, with description of a new subspecies from Nicaragua. By Sydney Anderson and J. Knox Jones, Jr. Pp. 519-529. January 14, 1960. | ||
| 20. | Small carnivores from San Josecito Cave (Pleistocene), Nuevo León, México. By E. Raymond Hall. Pp. 531-538, 1 figure in text. January 14, 1960. | ||
| 21. | Pleistocene pocket gophers from San Josecito Cave, Nuevo León, México. By Robert J. Russell. Pp. 539-548, 1 figure in text. January 14, 1960. | ||
| 22. | Review of the insectivores of Korea. By J. Knox Jones, Jr., and David H. Johnson. Pp. 549-578. February 23, 1960. | ||
| 23. | Speciation and evolution of the pygmy mice, genus Baimoys. By Robert L. Packard. Pp. 579-670, 4 plates, 12 figures in text. June 16, 1960. | ||
| Index. Pp. 671-690 | |||
| Vol. 10. | 1. | Studies of birds killed in nocturnal migration. By Harrison B. Tordoff and Robert M. Mengel. Pp. 1-44, 6 figures in text, 2 tables. September 12, 1956. | |
| 2. | Comparative breeding behavior of Ammospiza caudacuta and A. maritima. By Glen E. Woolfenden. Pp. 45-75, 6 plates, 1 figure. December 20, 1956. | ||
| 3. | The forest habitat of the University of Kansas Natural History Reservation. By Henry S. Fitch and Ronald R. McGregor. Pp. 77-127, 2 plates, 7 figures in text, 4 tables. December 31, 1956. | ||
| 4. | Aspects of reproduction and development in the prairie vole (Microtus ochrogaster). By Henry S. Fitch. Pp. 129-161, 8 figures in text, 4 tables. December 19, 1957. | ||
| 5. | Birds found on the Arctic slope of northern Alaska. By James W. Bee. Pp. 163-211, plates 9-10, 1 figure in text. March 12, 1958. | ||
| *6. | The wood rats of Colorado: distribution and ecology. By Robert B. Finley, Jr. Pp. 213-552, 34 plates, 8 figures in text, 35 tables. November 7, 1958. | ||
| 7. | Home ranges and movements of the eastern cottontail in Kansas. By Donald W. Janes. Pp. 553-572, 4 plates, 3 figures in text. May 4, 1959. | ||
| 8. | Natural history of the salamander, Aneides hardyi. By Richard F. Johnston and Gerhard A. Schad. Pp. 573-585. October 8, 1959. | ||
| 9. | A new subspecies of lizard, Cnemidophorus sacki, from Michoacán, México. By William E. Duellman. Pp. 587-598, 2 figures in text. May 2, 1960. | ||
| 10. | A taxonomic study of the middle American snake, Pituophis deppei. By William E. Duellman. Pp. 599-610, 1 plate, 1 figure in text. May 2, 1960. | ||
| Index. Pp. 611-626. | |||
| Vol. 11. | Nos. 1-10 and index. Pp. 1-703, 1958-1960. | ||
| Vol. 12. | 1. | Functional morphology of three bats: Sumops, Myotis, Macrotus. By Terry A. Vaughan. Pp. 1-153, 4 plates, 24 figures in text. July 8, 1959. | |
| *2. | The ancestry of modern Amphibia: a review of the evidence. By Theodore H. Eaton, Jr. Pp. 155-180, 10 figures in text. July 10, 1959. | ||
| 3. | The baculum in microtine rodents. By Sydney Anderson. Pp. 181-216, 49 figures in text. February 19, 1960. | ||
| *4. | A new order of fishlike Amphibia from the Pennsylvanian of Kansas. By Theodore H. Eaton, Jr., and Peggy Lou Stewart. Pp. 217-240, 12 figures in text. May 2, 1960. | ||
| 5. | Natural history of the bell vireo. By Jon C. Barlow. Pp. 241-296, 6 figures in text. March 7, 1962. | ||
| 6. | Two new pelycosaurs from the lower Permian of Oklahoma. By Richard C. Fox. Pp. 297-307, 6 figures in text. May 21, 1962. | ||
| 7. | Vertebrates from the barrier island of Tamaulipas, México. By Robert K. Selander, Richard F. Johnston, B. J. Wilks, and Gerald G. Raun. Pp. 309-345, pls. 5-8. June 18, 1962. | ||
| 8. | Teeth of Edestid sharks. By Theodore H. Eaton, Jr. Pp. 347-362, 10 figures in text. October 1, 1962. | ||
| More numbers will appear in volume 12. | |||
| Vol. 13. | 1. | Five natural hybrid combinations in minnows (Cyprinidae). By Frank B. Cross and W. L. Minckley. Pp. 1-18. June 1, 1960. | |
| 2. | A distributional study of the amphibians of the Isthmus of Tehuantepec, México. By William E. Duellman. Pp. 19-72, pls. 1-8, 3 figures in text. August 16, 1960. | ||
| 3. | A new subspecies of the slider turtle (Pseudemys scripta) from Coahulia, México. By John M. Legler. Pp. 73-84, pls. 9-12, 3 figures in text. August 16, 1960. | ||
| 4. | Autecology of the copperhead. By Henry S. Fitch. Pp. 85-288, pls. 13-20, 26 figures in text. November 30, 1960. | ||
| 5. | Occurrence of the garter snake, Thamnophis sirtalis, in the Great Plains and Rocky Mountains. By Henry S. Fitch and T. Paul Maslin. Pp. 289-308, 4 figures in text. February 10, 1961. | ||
| 6. | Fishes of the Wakarusa river in Kansas. By James E. Deacon and Artie L. Metcalf. Pp. 309-322, 1 figure in text. February 10, 1961. | ||
| 7. | Geographic variation in the North American cyprinid fish, Hybopsis gracilis. By Leonard J. Olund and Frank B. Cross. Pp. 323-348, pls. 21-24, 2 figures in text. February 10, 1961. | ||
| 8. | Descriptions of two species of frogs, genus Ptychohyla; studies of American hylid frogs, V. By William E. Duellman. Pp. 349-357, pl. 25, 2 figures in text. April 27, 1961. | ||
| 9. | Fish populations, following a drought, in the Neosho and Marais des Cygnes rivers of Kansas. By James Everett Deacon. Pp. 359-427, pls. 26-30, 3 figs. August 11, 1961. | ||
| 10. | Recent soft-shelled turtles of North America (family Trionychidae). By Robert G. Webb. Pp. 429-611, pls. 31-54, 24 figures in text, February 16, 1962. | ||
| Index. Pp. 613-624. | |||
| Vol. 14. | 1. | Neotropical bats from western México. By Sydney Anderson. Pp. 1-8. October 24, 1960. | |
| 2. | Geographic variation in the harvest mouse. Reithrodontomys megalotis, on the central Great Plains and in adjacent regions. By J. Knox Jones, Jr., and B. Mursaloglu. Pp. 9-27, 1 figure in text. July 24, 1961. | ||
| 3. | Mammals of Mesa Verde National Park, Colorado. By Sydney Anderson. Pp. 29-67, pls. 1 and 2, 3 figures in text. July 24, 1961. | ||
| 4. | A new subspecies of the black myotis (bat) from eastern Mexico. By E. Raymond Hall and Ticul Alvarez. Pp. 69-72, 1 figure in text. December 29, 1961. | ||
| 5. | North American yellow bats, "Dasypterus," and a list of the named kinds of the genus Lasiurus Gray. By E. Raymond Hall and J. Knox Jones, Jr. Pp. 73-98, 4 figures in text. December 29, 1961. | ||
| 6. | Natural history of the brush mouse (Peromyscus boylii) in Kansas with description of a new subspecies. By Charles A. Long. Pp. 99-111, 1 figure in text. December 29, 1961. | ||
| 7. | Taxonomic status of some mice of the Peromyscus boylii group in eastern Mexico, with description of a new subspecies. By Ticul Alvarez. Pp. 113-120, 1 figure in text. December 29, 1961. | ||
| 8. | A new subspecies of ground squirrel (Spermophilus spilosoma) from Tamaulipas, Mexico. By Ticul Alvarez. Pp. 121-124. March 7, 1962. | ||
| 9. | Taxonomic status of the free-tailed bat, Tadarida yucatanica Miller. By J. Knox Jones, Jr., and Ticul Alvarez. Pp. 125-133, 1 figure in text. March 7, 1962. | ||
| 10. | A new doglike carnivore, genus Cynaretus, from the Clarendonian Pliocene, of Texas. By E. Raymond Hall and Walter W. Dalquest. Pp. 135-138, 2 figures in text. April 30, 1962. | ||
| 11. | A new subspecies of wood rat (Neotoma) from northeastern Mexico. By Ticul Alvarez. Pp. 139-143. April 30, 1962. | ||
| 12. | Noteworthy mammals from Sinaloa, Mexico. By J. Knox Jones, Jr., Ticul Alvarez, and M. Raymond Lee. Pp. 145-159, 1 figure in text. May 18, 1962. | ||
| 13. | A new bat (Myotis) from Mexico. By E. Raymond Hall. Pp. 161-164, 1 figure in text. May 21, 1962. | ||
| 14. | The mammals of Veracruz. By E. Raymond Hall and Walter W. Dalquest. Pp. 165-362, 2 figures. May 20, 1963. | ||
| 15. | The recent mammals of Tamaulipas, México. By Ticul Alvarez. Pp. 363-473, 5 figures in text. May 20, 1963. | ||
| More numbers will appear in volume 14. | |||
| Vol. 15. | 1. | The amphibians and reptiles of Michoacán, México. By William E. Duellman. Pp. 1-148, pls. 1-6, 11 figures in text. December 20, 1961. | |
| 2. | Some reptiles and amphibians from Korea. By Robert G. Webb, J. Knox Jones, Jr., and George W. Byers. Pp. 149-173. January 31, 1962. | ||
| 3. | A new species of frog (Genus Tomodactylus) from western México. By Robert G. Webb. Pp. 175-181, 1 figure in text. March 7, 1962. | ||
| 4. | Type specimens of amphibians and reptiles in the Museum of Natural History,
the University of Kansas. By William E. Duellman and Barbara Berg. Pp. 183-204. October 26, 1962. | ||
| 5. | Amphibians and Reptiles of the Rainforests of Southern El Petén, Guatemala. By William E. Duellman. Pp. 205-249, pls. 7-10, 6 figures in text. October 4, 1963. | ||
| 6. | A revision of snakes of the genus Conophis (Family Colubridae, from Middle America). By John Wellman. Pp. 251-295, 9 figures in text. October 4, 1963. | ||
| 7. | A review of the Middle American tree frogs of the genus Ptychohyla. By William E. Duellman. Pp. 297-349, pls. 11-18, 7 figures in text. October 18, 1963. | ||
| More numbers will appear in volume 15. | |||