Read Ebook: The History of Java v. 1-2 by Raffles Thomas Stamford Sir

Font size: 10 px 15 px 20 px 25 px 30 px 35 px

Background color: BlackWhiteGrayLight GrayDark GrayDim Gray

Text color: BlackWhiteGrayLight GrayDark GrayDim Gray

Apply/Save settings

Ebook has 42 lines and 6899 words, and 1 pages

PAGE

INTRODUCTION 253

ACKNOWLEDGMENTS 254

MATERIALS AND METHODS 254

TAXONOMIC RELATIONSHIPS AND EVOLUTION 291

SUMMARY 292

LITERATURE CITED 293

INTRODUCTION

ACKNOWLEDGMENTS

Prof. William E. Duellman supplied invaluable information and guidance in my study. I am grateful to Prof. E. Raymond Hall for use of facilities of the Museum of Natural History and editorial assistance. I thank Prof. Laurence C. Stuart and Prof. Edward H. Taylor for information and suggestions. My own field experience in Middle America came as a result of assisting Professor Duellman in his own researches supported by a grant from the National Science Foundation . For these things I am deeply grateful. Specimens that I have seen alive were collected by field companions Dale L. Hoyt and Jerome B. Tulecke. Finally, I am grateful to my wife, Margaret L. Wellman, for much help including typing much of the manuscript.

MATERIALS AND METHODS

Measurements were taken to the nearest millimeter by means of a millimeter stick. Body length is the distance from the tip of the snout to the posterior edge of the anal plate; tail length, from the latter point to the tip of the tail; and total length, the sum of the body plus tail.

Descriptions of color are based on preserved specimens. Where descriptions of the color of living individuals are given, the data were taken from Kodachrome slides made available to me by William E. Duellman. Due to the transient nature of the longitudinal dark stripes in these snakes, no standard terminology has been devised, except that the posterior continuations of the stripes which on the head pass through the eye are termed lateral stripes; the posterior continuations of the median stripe of the head are termed dorsolateral stripes. A paravertebral stripe is one that is present on the scale-row on either side of, but not including, the mid-dorsal scale-row.

In order to reduce confusion in the discussion of variation, the numbers designating the rows of dorsal scales are written as 1st, 2nd, whereas the numbers designating the stripes are written as first, second.

In accounts of the species and subspecies, the observed range of variation is followed by the mean in parentheses; in some instances the mean is followed by the standard deviation, also in parentheses. An example is 65-79 .

Each synonymy includes all generic and specific combinations known to me that have been used for the genus, and, in addition, references to catalogues, checklists, and reports of collections.

Localities of occurrence that are not plotted on the distribution maps are recorded in italic type under Specimens Examined. In the list of Specimens Examined the localities and specimens are listed in the following order: countries in alphabetical order; states or departments in alphabetical order in each country; localities in alphabetical order in each state or department; museum numbers in numerical order after the abbreviations of names of museums. When more than one specimen bears a single catalogue number, the number of specimens is given in parentheses following the museum catalogue number. Specimens for which data are given only as to country or to state or department are listed first after the name of that political unit under "no specific locality."

The abbreviations for the museum collections are:

AMNH American Museum of Natural History ANSP Academy of Natural Sciences of Philadelphia BMNH British Museum CAS California Academy of Sciences CNHM Chicago Natural History Museum ERA-WTN E. Ross Allen-Wilfred T. Neill, Ross Allen's Reptile Institute KU University of Kansas Museum of Natural History MCZ Museum of Comparative Zoology, Harvard MVZ Museum of Vertebrate Zoology, University of California NMW Naturhistorisches Museums Wien, Vienna SU Stanford University Natural History Museum TCWC Texas Cooperative Wildlife Collection, Agricultural and Mechanical College of Texas UF University of Florida Collections UIMNH University of Illinois Museum of Natural History UMMZ University of Michigan Museum of Zoology USNM United States National Museum

Family COLUBRIDAE

Subfamily Xenodontinae

The only previous attempt to review the systematics of this genus was made by Smith who based his study primarily on specimens in the United States National Museum. He examined only 28 specimens, including none of one species .

KEY TO THE SPECIES AND SUBSPECIES

Although many juveniles differ greatly in general coloration from the adults, both the juveniles and the adults of any species or subspecies can be identified from the following key; juveniles differ from adults in extent and intensity of dark pigmentation but not in rows of scales involved.

Eight supralabials ; unstriped or with more than 4 dark stripes along body, or dark with 2 or 4 pale stripes 3

Supralabials immaculate or having dark borders below; head and body usually pale with dark stripes, or without stripes 4

Lateral dark stripe becoming indistinct on body, or restricted to 4th or 3rd and 4th rows anteriorly, not involving 2nd scale-row on anterior 1/3 of body ; no paravertebral stripes 5

Stripes present posteriorly; 1st scale-row pigmented 6

Analysis of Characters

Characters showing inter-specific and intra-specific variation and that have a wide range of variation were analyzed statistically, when possible, in order to determine extent of variation. One character was analyzed for sexual dimorphism, and for it the coefficient of difference is also given. The statistical terms and formulae have been adopted from Mayr, Linsley and Usinger . Dorsal head shields varied individually and were of no taxonomic importance. Osteological and hemipeneal characters did not show enough variation to be considered here.

Scutellation

Labials, dorsals, ventrals, and subcaudals were the most useful scales.

TABLE 1.--VARIATION IN THE PLACE OF DOSAL SCALE REDUCTION IN CONOPHIS.

Size and Proportions

TABLE 2.--VARIATION IN THE NUMBER OF VENTRALS IN CONOPHIS.

TABLE 3.--SEXUAL DIMORPHISM AS INDICATED BY VARIATION IN THE NUMBER OF SUBCAUDALS IN CONOPHIS.

Color Pattern

Every stripe originates either as broad continuous stripe or as a row of spots or dashes, forming a discontinuous stripe, which in some specimens becomes continuous posteriorly. The stripes are usually black or deep brown, although auxiliary stripes are sometimes paler. The dorsal ground color is pale brown, tan, olive, or white; usually the ground color is palest ventrally and darkest dorsally.

Sexual Dimorphism

Formulation of a biological concept of the species as defined by Mayr is difficult when most of the data primarily relied upon are from preserved specimens. Nevertheless, a total view of variation was attempted so that differences within and between populations could be recognized. Differences, between populations, that seem to be part of a continuous or internal cline are not used for characterizing subspecies.

The ventrals usually have more or less conspicuous dark spots laterally on those specimens having dark stripes present on the dorsum; spots are absent on all specimens having no dorsal stripes and on some specimens having dorsal stripes. Except for the dark lateral spots the ventrals are immaculate white. Usually the dorsal ground-color is pale tan, especially on the striped forms. The ground-color is usually palest on the lower dorsal scale rows and darkest dorsally.

Three populations are separable as subspecies; one has no stripes on the body and occurs in the Yucat?n Peninsula. The other two have stripes on the dorsum and vary clinally in coloration from the north to south . Reasons for separating these widespread, variable snakes into two subspecies are that they are discontinuous in distribution , and that these populations have distinctly different color patterns.

Share on: WhatsApp @Hash Facebook Tweet