A Few Common Spiders at ACR A Few Common Spiders at ACR Mygalomoprh (“primitive”) Spiders Orb Weavers egg case back abdomen Yellow & Black Garden Spider Silver-banded Garden Spider (Argiope aurantia) False Tarantula (Argiope trifasciata) Turret Spider (Atypoides sp.) Trapdoor Spider (Aliatypus sp.) - both of these spiders hang head down in web Calisoga longitarsus egg case •Turret of stiff silk •Look for trapdoors in mossy - both of these spiders have webs with a stabilimentum Look for burrows in •Added to each year banks in road cuts and along the middle of trails; almost •Up to 8” long trails perfect circles; after •Can go 6 months without food! first rains evidence of •Can molt to get smaller! “spring cleaning.” Cribellate Spiders (produce fine hackle silk that “snaps”) Pumpkin Spider (Araneus trifolium) - build retreat to the side Debris Spider (Cyclosa conica) of web -line of debris down center of web False Widow -spider is concealed in debris Badumna sp. Steatoda grossa Labyrinth (Condo) These 4 spiders can be found around and on Spider buildings, in electrical and fire hose cabinets (Metepiera sp.) Triangle Spider (Uloborus sp.) -orb web with messy •Spider part of web portion (see above left) Missing Triangle •When she senses prey, she -Í retreat is in messy Spider → releases tension thread and portion (Zygiella sp.) triangle collapses -constructs lens-shaped -always a few on staff (look for these spiders in the egg sacs in retreat room railing redwoods under the heronry) Black Widow House Spider area Latrodectus hesperus Achaearanea tepoidariorum Hunting Spiders ↓Sheet Web Weavers→ Cellar Spider↑ -inside buildings and cabinets -touch web and watch it vibrate! ↑Filmy Dome Spider ↑Bowl and Doily Spider Crab Spider (w/ prey) (Neriene radiata) (Frontinella pyramiitela) -usually found on prepared by Gwen Heistand Wolf Spider (w/ egg sac) Camouflaged sit and Jumping Spider -spider hangs out on vegetation in cool, moist places for ACR Education Runs to catch prey wait predator Jumps at prey from above underside of “bowl” i Spider External Anatomy 28 Spider Silk Q: Do all spiders make the same kind of silk? A: No … and each individual spider is capable of making more than one kind of silk. 1. Aciniform glands: silk for wrapping prey, called swathing silk. Most spiders have this. 2. Cylindrical (tubuliform) glands: silk for wrapping eggs. So males usually don't have them, and some families (Salticidae and Dysderidaei) don't have them at all. 3. Ampullate glands: non-sticky silk for draglines or to form the frames of their webs (non-sticky foundations). All spiders have this, to produce the safety lines they leave behind them as they move about 4. Piriform glands: silk made into attachment disks at the bottom of web suspension lines. All families have them . 5. Aggregate glands work like a glue gun, producing sticky droplets, which regularly dot the silk to trap prey. Only three families have them (Araneidae, Theridiidae and Linyphiidae) 6. Lobed glands: wrapping silk (only in Theridiidae which have reduced aciniform glands). 7. Cribellar glands: fluffy woolly silk that is very fine and combed into a single strand. (very stretchy and good for catching flying insects because insect bounces back to the web like on a horizontal bungee jump). The woolly silk also snares hairy insect legs. Only cribellate spiders have these gldlands an d com b(bs (see page 9). 27 Spinnerets TABLE OF CONTENTS Q: How do spiders make silk? Spider External Anatomy……………………………………………….. i What Makes a Spider a Spider? / A: They have structures called spinnerets. Silk comes out from tiny nozzles Types of Spiders (Mygalomorph vs Araneomorph spiders) ………….. 1 as a liquid. Tension causes it to solidify. It is one of the strongest lightweight substances known. Spider silk is 5 times stronger than steel Mygalomorph Spiders and about 3 times tougher than Kevlar. According to the folks that have Dipluridae: False Tarantula (Calisoga longitarsus) …………………… 2 tried to raise spiders for silk, it’s like trying to farm tigers. Think about it. So, Antrodiaetidae the US Army and a Canadian firm have figured out how to insert the silk Trapdoor Spider (Aliatypus sp.)………..……………………… 3 produc ing genes f rom spid ers i n goat s and , voil a, th e goat milk cont ai ns Turret Spiders (Atypoides sp.)………………………………… 5 spider silk. Araneomorph Spiders Uloboridae Triangle spider (Uloborus sp.)………………………………… 6 Linyphiidae: Sheet Web Weavers Bowl & Doilyyp Spider (Frontinella spp).)………………………… 7 Filmy Dome Spider (Neriene sp.)…………………………….. 8 Agelenidae: Funnel Web Spiders………………………...…….. 9 Desidae: Badmuna sp. (From Australia)…………………………….. 9 Theridiidae: Comb-footed Spiders Black Widow or Western Widow (Latrodectus hesperus)………… 10 False Widow (Steatoda grossa)………………………………. 10 House Spider (Achaearanea tepidariorum)…………………….. 10 Pholcidae: Cellar Spiders ……………………………………... 11 Araneidae: Orb Weavers ……………………………………… 12 Pumpkin Spider (Araneus trifolium)…………………………. 13 Yellow & Black Garden Spider (Argiope aurantia)……………. 14 Silver banded Garden Spp(ider (Argiopep trifasciata)……………… 15 Debris Spider (Cyclosa sp.)………………………………….. 16 Labyrinth or Condo Spider (Metepeira sp.)……………………. 17 Long-Jawed Spider (Tetragnatha sp.)………………………… 18 Missing Triangle Spider (Zygiella sp.)………………………… 19 (Hunting Spiders) Lycosidae : Wolf Spiders …………………………………...…. 20 Salticidae: Jumping Spiders ………………………………….. 21 Thomisidae: Crab Spiders ……………………………………. 22 Identification Characteristics Pedipalps…………………………………………………………... 23 Eyes………………………………………………………………. 24 Spider Reproduction / Mating…………..…………………...………… 25 Molting…………………………………………………………….…….. 26 Colorized scanning em of silk coming out Scanning em of Aciniform Gland spools (see Spinnerets……………………………………………………………….. 27 spigots center of diagram above): this is th gland Types of Silk…………………...………………………………………... 28 that makes silk for wrapping prey 1 26 What Makes a Spider a Spider? How Do Spiders Grow? •Abdominal silk glands and spinnerets Spiders have an external skeleton which they need to •Males with palpal sperm transfer •Cheliceral v enom glands shed in order to grow. Those spider bodies you see in your hose that are hanging out in webs and not moving All Arachnids (spiders, ticks, mites, opiliones, scorpions, whip are often the shed exoskeletons of the actual spider. scorpions, pseudoscorpions, sun spiders) have: •4 pairs of walking legs •Two body segments (cephalothorax & abdomen) 2 Major Groups of Spiders Mygalomorph False tarantulas (and real ones) along with our turret spiders and trapdoor spiders are all ppjgpgart of a major grouping called mygalomorph spiders. These spiders are considered to be more primitive. Their fangs only move up and down instead of side-to-side (they operate parallel to the midline of their body, not perpendicular to it). So … mygalomorphs moves up and down need to rear up and come down on their prey, trapping them against a surface. Mygalomorphs have 2 pairs of book lungs (and only book lungs ) which distinguish them from all but one group of the “true spiders”. Mygalomorphs also have long, segmented, spinnerets, which trail out behind their body visibly. Their eyesight is not great and courtship often relies on the male stroking and caressing the female. Mygalomorphs are long-lived (females 8-20 years, males 3-7 years!). Araneomorph (“True” Spiders) 90% of spider species are araneomorphs. Fangs these spp(iders (orb weavers, sheetweb moves weavers , wolf spiders, crab side-to- spiders, jumping spiders, etc.) are side able to move side to side. Their jaws work independently from any surface and they are able to impale their prey between them. This allows araneomorphs to ca tc h prey on the flimsy surface of their webs. Along with one pair of book lungs, most araneomorphs also have tubular tracheae.. 25 2 Spider Reproduction False Tarantula (Calisoga longitarsus) • Courtship involves lots of signaling (vibrational visual, chemical) and different courtship positions (see below) Q: What do these spiders look like? • Male sacrifice is less common than believed. • Pedipalps and epigynum act as lock and key (see page 23) A: They’re large and “tarantula-like” though • Male spigots for sperm web are not part of spinnerets not as large as the tarantulas we are familiar • Use varying amounts of silk to protect eggs with. In the fall, I often get calls from people • Egg numbers vary between 1 and 1000 (cave spiders produce 1 big that find large spiders in their bathrooms or egg) around their house. The males of this species • Developmental stages go on walk-about in the fall searching for • Prelarva (immotile –usually in egg) females and it is usually this spider that • Larva (limited motility and leg segmentation) people are asking about. Q: Where can we find Calisoga • Nymph – motile, venom (can feed), functional spinnerets burrows? • Generally, araneomorphs don’t molt past maturity; female mygalomorphs molt throughout life (shed spermatheca so need to Look in the middle of trails and trail get reinseminated) and males don’t molt once they’re mature. margins,,p especially on the Griffin trail • MtMaterna lcare (fema les o f some groups guard egg cases and across the Sheerin Bridge and the first spiderlings) part of trail to Volunteer Canyon. I’ve also seen them on the trail past the spider patch on the way under the heronry. In the fall, after the first rains, they’re easier to spot. Look for little piles of dirt and a white glob next to an almost perfectly round hole about the size of a nickel. The white glob is the remains of last year’s egg sac. If you tease it open and have a hand lens you can see the Q: Where do these spiders get their shed exoskeletons of the tiny sometimes common name of spiderlings who undergo their first molt mygalomorph mating positions “aggressive false tarantula”? while still in the sac! orb weaver mating positions • Male approaches female • Often, male will create a from front, female raises A: They have a threat display of rearing Q: If these are “false” tarantulas … do courtship line to the web prosoma, male inserts up on hind four legs, raising and we have “true” tarantulas at BLP? • Males are often a lot palps spreading the front four, and baring the smaller than females fangs.