Arachnophobe to Arachnophile. Presented by: Wes Robertson Henrico County Standing Water Initiative

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1 Arachnophobe to Arachnophile Presented by: Wes Robertson Henrico County Standing Water Initiative

2 Introducing the Spectacular Spider Found worldwide Found in a variety of climates 42,000 plus species 110 families All are carnivores All produce silk All have fangs Comb-Clawed Spider Theridiidae spp.

3 What makes a spider a spider? 2 Body Segments Eyes Spinnerets 8 Segmented Legs Chelicerae Pedipalps Dysdera Crocata Woodlouse Spider

4 Why look beyond the eight legs? Velvet Ant Mimic Spider Castianeira White-banded Daddy long amoena legs Crab Spider Lebobunum Misumenoides spp. Velvet (Not really formosipes Ant a Dasymutilla spider) occidentalis

5 The Developmental Cycle Spider shape is established Egg Cannot feed or mate Larva Nymph Self-sufficient and sexually mature Adult Virginia Tan Jumping Spider

6 Continued Development Molting is the key to developmental progression. The average spider lives between 1-2 years and molts 3 and 15 times during that time. Therefore, immediately following the first molt, each spiderling must become adapted for hunting and capturing prey. However, they must first disperse.

7 Spiders are a Key Component in Aerial Plankton The most common form of spider dispersal is ballooning. Spiders utilize rising air currents to move shortly after emergence.

8 An Integral Pioneering Arthropod Wind Picks up Ballooning Occurs Secondary Prey New acts Pioneering Succession as Growth trapped Species nutrients Occurs Established Territory Vacant Territory

9 Why is this important? Young and old ecosystems depend on a fragile balance between competition and interdependence. While spiders are not effective biological control agents against specialized targets they help maintain balance within the insect world. This balance results in an increase in overall diversity.

Developing the Ability to Identify, Then

10 Developing the Ability to Identify, Then Recognize However, in order to understand their role in the ecosystem, we must develop an appreciation of their value and uniqueness. This is achieved through identification and recognition. The key to basic identification is observation Observe the habitat and/or webs Observe the prey options Observe their movement, size, & body form Dysdera crocata Woodlouse spider

11 Identify the Habitat and the Web Spring door with silk hinge Cellar Habitat Forest Floor Southern Trap-door Spider Ummidia audouini Crevice with radial symmetry Southern House Spider Crevice Weaver Kukulcania spp.

12 Identify the Habitat and the Web Garage Floor Garage and House Ceiling Tangle Webs No, not the same as this guy. (Opiliones a.k.a. Harvestman) Southern Black Widow Latrodectus mactans False Widow - Steatoda borealis House Spider Parasteatoda tepidariorum Daddylonglegs (Cellar Spider) Pholcus phalangioides

13 Identify the Habitat and the Web Mesh Web Dictyna arundina Hammock Spider Ceiling Corner Garden Plant Forest Understory Sac Web and Long-Legged Sac Spider

14 Identify the Habitat and the Web Back porch and foundation bushes Front lawn or on sides of house Orchard Weaver Trash line Weaver Common Grass Spider Agelenopsis spp.

15 Identify the Habitat and Web Tall Garden Vegetation Backyard Rock Hacklemesh Web Wagon Wheel Web Longjawed Orbweaver Tertragnathidae spp. Hacklemesh Weaver Amaurobius ferox

16 Identification of Webless Spiders Ground Spiders Jumping Spiders Woodlouse Spiders Recluse Spiders Prowling Spiders Wolf Spiders Crab Spiders

17 Identify the Size and Body Form Arrow-Shaped Micrathena Wall Spider Raptorial spine legs Magnolia Green Jumper Forward Legs Crab Spider White-banded crab (Misumenoides formosipes) Tiger Wolf Brown Recluse Size demonstration

18 Identification of Different Sexes Usually smaller Males Thicker palpal tarsi Final molt equals wandering Stops eating during wandering Can become female prey Several mating events before dying Females Larger Live Longer Lay eggs and build cocoons Some exhibit brood care

19 Visualization of Spider Sexes Female Dorsal Side Male Male Southern Black Widow Latrodectus mactans Female Female Ventral Side Yellow Garden Spider Argiope aurantia

20 Identifying Virginia s Venomous Spiders Latrodectus (Widow species) Virginia has two widow species I. Southern Black Widow II. (Latrodectus mactans) Northern Black Widow (Latrodectus variolus) Characteristic Hourglass patterns Tangled Web (Extremely messy and low to the ground) As big as a half dollar and clumsy when not in web Northern Mature Ventral View Southern Immature Dorsal View

21 Differences Between Mature Females Northern - variolus Southern - mactans

22 Differences Between Mature Females Northern - variolus Southern - mactans

23 Differences Among Immature Females Northern - variolus Southern - mactans

24 Identifying Venomous Spiders Sicariidae Brown Recluse Not a Virginia Resident Violin but better id through counting eye dyads 3 dyads Not Here! Recluse distribution

25 Brown Recluse Identification Fiddle present Eye Dyads present Generally quarter size Generally nocturnal Ground Spider extremely fast

Conclusion Arachnids have been around for 440 million years and there are roughly 38,000 species of spiders alone. This fact makes arachnids an amazingly diverse group of invertebrates.

26 Conclusion Arachnids have been around for 440 million years and there are roughly 38,000 species of spiders alone. This fact makes arachnids an amazingly diverse group of invertebrates. I have tried to introduce you to the basics of spider identification with the hope that, through practice, you too, will be able to recognize many common species with less malice and fear.

An Introduction to the Spiders of Chicago Wilderness, USA Common Spiders of the Chicago Region

An Introduction to the Spiders of Chicago Wilderness, USA Common Spiders of the Chicago Region Common Spiders of the Chicago Region 1 ARANEIDAE ORB WEAVERS Orb Weavers and Long-Jawed Orb Weavers make classic orb webs made famous by the book Charlotte s Web. You can sometimes tell a spider by its