Plestiodon Skinks -- Getting it Right!
Now, the postlabials are a spectacular guide to whether or not you have a a Broadhead Skink or not. Broadheads have one (rarely two) small postlabials if they have them at all. Southeasterns will have two medium-sized postlabials, and Commons will have two, large postlabials. Look at the photo above where I have both scale types counted and color-coded.
The same Common Five-lined Skink on different sides | © Ty Smith
Common Five-lined Skinks will almost always have 3 scale rows between the mid-dorsal and lateral on their lower back, while Southeasterns will have four or sometimes five. Broadhead Skinks will often have three rows as well, but the line patterning is a little different.
Below is an excerpt from my field journal. Let me be clear, this example is purely based on my observations and not backed up by any study I am aware of.
Common Five-lined Skink
Common Five-lined Skinks have pretty standard lines. On juvenile and female individuals where lines are visible, the mid-dorsal is a thick, and the other lines are similar in width (never exceeding the thickness of the mid-dorsal). All lines are the same color and fade evenly on all individuals, being a cream or golden color; usually taking up two-half scale rows. The lines on the face are the same color as the rest of the body, and the sublateral fades into the face pattern. On Commons, these lines thicken with age. Adult males are not too tricky either most of the time. Lines on male Common all fade at the same rate. I have never seen one that had any line or lines that stood out more than any other. Note: the amount of line visibility does vary from Skink to Skink, but all lines will be quite similar in size and color. The section of the sublateral that runs from the snout to ear is what we refer to as the subocular line. I mentioned this fades into the face pattern on female Commons, but it is not normally visible on breeding males. If they do retain this portion of the line, it is very faint. That said, it reappears on the same males when in their non-breeding colors. Male Common Five-lined Skinks retain several, random black scales. The other species rarely retain these, but scars can look similar at a distance. Females retain these too, but it is not as clear on them. The base color between the lateral and sublateral lines is often slightly or, sometimes, much darker than that between the lateral and mid-dorsal.
Southeastern Five-lined Skink
We will make this very simple for females and juveniles. Their lines are very thin and clean. If you look at the lines in the area over the hips, you can compare them to that of the Common to get an ID. The mid dorsal on Southeasterns is rarely the widest line. On juveniles, these lines can seemingly fade out just before the tail, but are bright and orange on the head. Females retain a lot more of that black base color, while lines fade often to white. Sometimes, as the base color slowly turns gray, a black outline will be visible around the lines excluding the subocular. The subocular line does not fade into the face, and contrast a bit more than that of the Common. On females, the base color between the lateral and sublateral lines is often slightly darker than that between the lateral and mid-dorsal, with much more contrast on the males.
Males are very contrasting. They almost always retain the bright, white sublateral even on the face. Sometimes the lateral line will be retained, but the mid-dorsal tends to be much duller, and often will fade out completely during breeding. Their heads do not swell much during breeding like the other two do.
A slight majority of juvenile Broadheads are going to make your life very simple, as they will have seven lines. These additional lines tend to run from the front to hind leg. The other lines are often much thicker than the Southeastern, yet not as uniform as the Common. Hatchlings tend to have richer line colors on their heads than the rest of their body. This fades quickly, but Broadheads feel overall more ornate than their cousins keeping brighter yellow lines, and light flecks on the hind legs. This species often hatches with coppery or rufous superlabials, and the facial line often wraps these instead of encompassing them. I will admit, that the Broadhead's variable line thickness means there is a short period of time when some individuals are very similar to Common Five-lined Skinks, and photos with poor detail can be impossible to distinguish. Their necks thicken, and their body starts to become more coppery with a little growth. This is when their lines start becoming paler. Quickly into this phase, one can start seeing a thick, dark outlining on their lines excluding the subocular. This subocular stays quite contrasting from the rest of the face. Eventually, the skink will develop a thick, fatty dewlap. Males have larger dewlaps, as these are to protect the neck from the jaws of other Broadheads.
Males often retain a much brighter, white sublateral, and a strong subocular line as well, until they are much older. These lines may fade completely on older males. Non-breeding males revert to that rich copper-color, and often display their lines again. The sublaterals are always the brightest and the mid-dorsal is the dullest.
Adult male Broadheads are beasts. Now, it seems Broadheads in NOVA are not as large as in the southeast, but the build is much different. I always liken it to a Chimpanzee and a Gorilla. They are both black, hairy apes, but the Gorilla is easy to ID from a silhouette because it is big and bulky. I have seen a male Broadhead Skink catch and eat a female Common Five-lined Skink. They are that big. Broadheads are so big, their juveniles will retain colors well pasted the size of an adult Common Five-lined Skink. I will say, in my full, honest opinion: the best way to distinguish male Broadhead Skinks from Common Five-lined Skinks without any feature is with size and build. That said, most people cannot properly judge size even at a distance of ten feet; but photos on bricks or other objects of known size should be easily identified without detailed pattern or scales.
How about Range Maps?
Common Five-lined Skinks are statewide. Nothing more to say... But Broadheads are a bit more patchy. They could be anywhere with proper habitat, excluding much of the Blue Ridge and Valley and Ridge, so I just recommend checking the map on the species profile.
Wrapping it all Up
I mentioned these misidentifications were harmful in the intro, but let me elaborate why. Say the Common Five-lined Skink started expanding due to its ability to thrive in human settlements, while Broadheads are being pushed out. We would almost certainly never know if the Broadhead's population was in danger or not if 30% of Commons are being misidentified as Broadheads. Say Southeastern Five-lined Skinks start declining drastically, and DWR allocates funding towards protecting this species on known sites. Well, if there are random records all over the state that have been misidentified, that spreads the money thin and gives too much to areas where the skink is never found. Now, I know the rebuttal to my examples is: "these species are stable". I do not disagree. All three species appear "stable", but I would argue that Broadheads in the south have and still are declining. I would not say they are rare or should be threatened, but we should keep an eye on these lizards. The lack of decline or the commonality of a species does not mean it will not need help eventually. The Passenger Pigeon should be the only example I need to give you... We can look at historical data to help us better understand changes. But historical data is only helpful if it is accurate. Let us start the trend of correcting the wrong on these beautiful lizards, and start getting our skinks right.
For papers, I have linked Reptile Database below so you can cruise the papers at your own leisure.
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