Check out this interview with Lila Higgins and Sam Easterson, the folks behind the Spider Pavilion!
Become a Naturalist Member or above for an invitation to an enchanting and mysterious Halloween celebration. Learn more >
Thanks to everybody that came out to the Spider Pavilion 2011. Check out our Spider Photos group on Flickr and upload your pictures to share with us! View more
Follow the yellow brick road to the 9th Annual Haunted Museum, Sunday, October 28, 2012.
Exclusively for members at the Naturalist level and higher.
The Los Angeles area has several species of common scorpions. By far the most common in our area is the burrowing scorpion or swollen stinger scorpion Anuroctonus phaiodactylus. Though males may occasionally be found wandering, these scorpions normally remain in their burrows. The burrows are found on sloping hillsides and road cuts and are almond-shaped openings about 1 inch in width and are about 8 to 12 inches deep. The pincers are very heavy and the tail is slender. Males have a distinct swollen base at the point of the stinger.
The California common scorpion Paruoctonus sylvestrii
Has four dark stripes on its fairly heavy tail. Its pincers are slender and it is brown or tan in color. These scorpions are often found on rocky ground and open road cuts in our hilly areas.
The Arizona bark scorpion Centruroides exilicauda has been established in several very small populations in Orange County where they live under roof shingles and in palm tree leaves. These scorpions are the only truly dangerous scorpion in North America. They are about 3 inches in length, slender, reddish or tan in color with very thin, almost needle-like pincers and a slender tail.
These animals are actually crustaceans, as can be seen by their gills and antennae. There are few references to them, one key for the terrestrial isopods is Light's Manual: Intertidal Invertebrates of the Central California Coast, U. of C. Press, pp. 301-312.
Armadillidium vulgare (Photo by: Franco Folini)
The pillbug is completely ubiquitous everywhere European man has set foot. This isopod is capable of rolling into a ball when disturbed; only a few other rare local species can do this and these are mostly sea-shore or desert animals. It is commonly preyed on by Steatoda grossa (which may even be a specialist on them).
Porcellio sp. sow bugs: We have three species of these isopods. P. laevis is more common in moist areas and yards and is often numerous near streams. It tends to be smoother with more rounded front plates than P. dilatatum. P. dilatatum is perhaps slightly more common in dryer (but moist) areas and in gardens. It has a more granular, dry appearance with rearward projecting plates on the first segments.
P. scaber is occasionally found in our area near streams and in moist canyons, especially further up the coast. It is slightly more slender than P. laevis but otherwise similar.
Porcallionides pruinosus: These isopods have a powdery appearance and are smaller, more slender than Porcellio. They also tend to be slightly more active. Often seen in gardens alongside Porcellio and Armadillidium, they run rapidly with the body held higher. All of the above isopods (except perhaps P. scaber) tend to be common throughout our area and may all be found together in our area.
Ligia occidentalis is the common rock hopper or rock louse found on rocky shores along the coast. Some specimens can be over an inch in length and can run rapidly.
Ligidium gracilis is a small and very rarely seen isopod that can be found in wet leaf litter and stream-side soil in our mountain streams and in a few locations along the coast. It is much more common further north.
Several species of small isopods are common in marsh and beach debris along the coast; most in the genus Armadilloniscus.
Occasionally isopods are found which are bright blue in color. This is common in A. vulgaire, less so in Porcellio. The color is apparently due to a fungal infection.