Ring-necked snake

Ring-necked snakes are fairly similar in morphology throughout much of their distribution. , California Its dorsal coloration is solid olive, brown, bluish-gray to smoky black, broken only by a distinct yellow, red, or yellow-orange neck band. A few populations in New Mexico, Utah, and other distinct locations do not have the distinctive neck band. Additionally, individuals may have reduced or partially colored neck bands that are hard to distinguish; coloration may also be more of a cream color rather than bright orange or red. First-year juvenile snakes are typically about and grow about a year depending on the developmental stage or resource availability. Ring-necked snakes have smooth scales with 15–17 scale rows at midbody. Males typically have small tubercles on their scales just anterior to the vent, which are usually absent in females. ==Distribution==

Ring-necked snakes are fairly common throughout much of the United States extending into southeastern Canada and central Mexico. Mexican populations diverged first in the phylogenetic lineage of the subspecies of ringneck species. Eastern populations cover the entire Eastern Seaboard from the Gulf of Saint Lawrence continuous through the Gulf Coast of Texas. Distribution moves inland into northern Minnesota, continuing diagonally through the US to include all of Iowa, eastern Nebraska, and most of Kansas. In the western US, the distribution is significantly less continuous, with spotty, distinct population segments through most of the Pacific Northwest. Populations extend from south-central Washington continuing along the extreme West Coast into Mexico. Population segments extend inland into western Idaho, through southern Nevada, into central Utah, and continuing south through Arizona and central Mexico. ==Habitat==

Ring-necked snakes occur in a wide variety of habitats. Preference seems to be determined by areas with abundant cover and denning locations. Since it is a woodland reptile, it can also commonly be found under wood or scraps. This cover is also utilized as a heat source instead of directly basking. Because of hot weather, they tend to make holes and burrows, or they hide under rocks or any suitable material. They are normally found in flatland forests. Though they prefer to remain away from human-made structures, ring-neck snakes are not afraid to utilize urbanized areas as refuge from predators. Moreover, throughout the year they tend to be active around March through October. ==Diet==

The diet of the ring-necked snake consists primarily of smaller salamanders, earthworms, and slugs, but they also sometimes eat lizards, frogs, and some juvenile snakes of other species. Ring-necked snakes use a combination of constriction and envenomation to secure their prey. In a study analyzing the dietary habits of this species, age, amount of food consumed, and temperature were conditions that highly affected digestion. The snakes do not have a true venom gland, but they do have an analogous structure called the Duvernoy's gland derived from the same tissue, which evolved to assist in the subduing of larger prey items. Most subspecies are rear-fanged with the last maxillary teeth on both sides of the upper jaw being longer and channeled; the notable exception is D. p. edwardsii, which is fangless. The venom is produced in the Duvernoy's gland located directly behind the eye. It then drains out of an opening at the rear of the maxillary tooth. Ring-necked snakes first strike and then secure the prey using constriction. Next, they maneuver their mouths forward, ensuring the last maxillary tooth punctures the skin and allowing the venom to enter the prey's tissue. The secretion significantly affects the righting response of the prey. Ring-necked snakes are rarely aggressive to larger predators, suggesting their venom evolved as a feeding strategy rather than a defense strategy. Rather than trying to bite a predator, the snake winds up its tail into a corkscrew, exposing its brightly colored belly. Ring-necked snakes are primarily nocturnal or highly crepuscular, though some diurnal activity has been observed. Individuals are sometimes found during the day, especially on cloudy days, sunning themselves to gain heat. Yet, most individuals lie directly under surface objects warmed in the sun and use conduction with that object to gain heat. Though ring-necked snakes are highly secretive, they do display some social structure, but the exact social hierarchies have never been evaluated. Many populations have been identified to have large colonies of more than 100 individuals, and some reports indicate some smaller colonies occupy the same microhabitats. ==Reproduction==

Ring-necked snakes usually mate in the spring. In some subspecies, though, mating occurs in the fall, and delayed implantation occurs. Three to ten eggs are deposited in June or July and hatch in August or September. The egg is elongated with a white color contrasted by yellow ends. When hatched, juveniles are precocial and fend for themselves without parental care. ==Threats==

One of the biggest threats the Key ring-necked snakes (Diadophis punctatus acricus) face is climate change. Native to the Florida Keys, the chain of low-level islands that make up the archipelago make the species highly vulnerable as rising sea levels impact their island habitat. They face storm surges and flooding events, which only expect to become more frequent as climate change worsens. Because of their small size and dependence on feeding off leaf litter prey, such as small invertebrates, these changes in climate directly impact food availability. ==Subspecies==

The following 14 subspecies are recognized. • D. p. acricus Paulson, 1966 — Key ring-necked snake • D. p. amabilis (Baird & Girard, 1853) — Pacific ring-necked snake • D. p. anthonyi (Van Denburgh & Slevin, 1942) — Todos Santos Island ring-necked snake • D. p. arnyi (Kennicott, 1859) — prairie ring-necked snake • D. p. dugesii () — Dugès' ring-necked snake • D. p. edwardsii — northern ring-necked snake • D. p. modestus (Bocourt, 1866) — San Bernardino ring-necked snake • D. p. occidentalis (Blanchard, 1923) — northwestern ring-necked snake • D. p. pulchellus (Baird & Girard, 1853) — coralbelly ring-necked snake • D. p. punctatus (Linnaeus, 1766) — southern ring-necked snake • D. p. regalis (Baird & Girard, 1853) — regal ring-necked snake • D. p. similis (Blanchard, 1923) — San Diego ring-necked snake • D. p. stictogenys (Cope, 1860) — Mississippi ring-necked snake • D. p. vandenburgii (Blanchard, 1923) — Monterey ring-necked snake ==References==