You are here
قراءة كتاب Hybridization Between Two Species of Garter Snakes
تنويه: تعرض هنا نبذة من اول ١٠ صفحات فقط من الكتاب الالكتروني، لقراءة الكتاب كاملا اضغط على الزر “اشتر الآن"
Hybridization Between Two Species of Garter Snakes
Garter Snakes
Museum of Natural History
August 15, 1946
University of Kansas
Lawrence
1946
Published August 15, 1946
Lawrence, Kansas
FERD VOILAND, JR., STATE PRINTER
TOPEKA, KANSAS
1946
Hybridization Between Two Species of Garter Snakes
By
HOBART M. SMITH
The chief characters distinguishing Thamnophis radix (Baird and Girard) and T. marciana (Baird and Girard) in southern Kansas are:
| marciana | radix | |
|---|---|---|
| 1. lateral light line involving only the 3d scale row anteriorly. | 1. lateral light line involving rows 3 and 4 anteriorly. | |
| 2. dorsal light line without distinct edges, varying in width from less than 1 to nearly 3 scale rows, at various places on body. | 2. dorsal light line with straight, even edges, 1½ scale rows wide. | |
| 3. several anterior lateral spots fused across lateral light stripes. | 3. usually no anterior lateral spots fused across lateral light stripes. | |
| 4. 2 posterior upper labials not light-centered, unlike others. | 4. 2 posterior labials light-centered, like others. | |
| 5. A well-developed, white, black-edged crescent behind angle of jaws (postrictal crescent). | 5. typically no well-developed postrictal crescent. |
Typical specimens of radix are available from several localities in Morton County of southwestern Kansas (Spring Creek; twelve miles and eighteen miles north of Elkhart; Elkhart); from the State Lake and Meade in Meade County; from Hunters, Harper County; Coolidge, Hamilton County; and Ingalls, Gray County.
Typical marciana is available from Spring Creek, Morton County; Liberal, Seward County; and Clark County (no locality). An overlap of range with radix is evident, and from Spring Creek in Morton County typical specimens of both species are available. Accordingly, at present, I conclude that the two forms are correctly regarded as distinct species.
Yet there is a rather marked tendency of radix to approach the characters of marciana in southwestern Kansas. Two specimens (one from Morton County, one from Gray County) have the dorsal stripe slightly broken up by infiltration of the ground color onto the edges of the scales. All southwestern radix develop the distinct postrictal crescent so characteristic of marciana, and occasional specimens fail to have light centers in the last two labials. Finally, one specimen from Meade, Meade County (No. 5434),