Oak Woodland Litter Spiders James Steffen Chicago Botanic Garden George Retseck Objectives • Learn about Spiders as Animals • Learn to recognize common spiders to family • Learn about spider ecology • Learn to Collect and Preserve Spiders Kingdom - Animalia Phylum - Arthropoda Subphyla - Mandibulata Chelicerata Class - Arachnida Orders - Acari Opiliones Pseudoscorpiones Araneae Spiders Arachnids of Illinois • Order Acari: Mites and Ticks • Order Opiliones: Harvestmen • Order Pseudoscorpiones: Pseudoscorpions • Order Araneae: Spiders! Acari - Soil Mites Characteriscs of Spiders • Usually four pairs of simple eyes although some species may have less • Six pair of appendages: one pair of fangs (instead of mandibles), one pair of pedipalps, and four pair of walking legs • Spinnerets at the end of the abdomen, which are used for spinning silk threads for a variety of purposes, such as the construction of webs, snares, and retreats in which to live or to wrap prey • 1 pair of sensory palps (often much larger in males) between the first pair of legs and the chelicerae used for sperm transfer, prey manipulation, and detection of smells and vibrations • 1 to 2 pairs of book-lungs on the underside of abdomen • Primitively, 2 body regions: Cephalothorax, Abdomen Spider Life Cycle • Eggs in batches (egg sacs) • Hatch inside the egg sac • molt to spiderlings which leave from the egg sac • grows during several more molts (instars) • at final molt, becomes adult – Some long-lived mygalomorphs (tarantulas) molt after adulthood Phenology • Most temperate spiders are univoltine (annuals) with a distinct mating period – many overwinter as juveniles, few as eggs – some winter-active adults (sub- niviean), too (especially linyphiids) • Small spiders sometimes multivoltine; large spiders often merovoltine (years per cycle) – female tarantulas may live > 20 years • More phenological variability farther north Sexual Dimorphism: male and female size differences in one species Misumena vatia(Thomisidae) Mobility Ballooning Sheet webs Reasons Why I Study Spiders #1 Reason: Diverse; Important Part of Earth’s Biodiversity • Order Araneae – 7th most diverse animal order – Most diverse order of all predators. • Global diversity – 43,244 species (3,879 genera, 112 families) • North American diversity – 3,500 species in 69 families – New local diversity still being found #2 Reason: Abundant, thus ecologically important • In all terrestrial/semiterrestrial ecosystems – Rainforest à Tundra – Wetlands à Deserts – Death Valley à Mount Everest • Biomass exceeds most vertebrates in most areas! – Capable of consuming 200kg/ha/yr (440 lbs.) – May approach 1 million individuals/ha #3 Reason: Predators closely associated with litter arthropods • Larger and less diverse than many litter arthropods so “easier” to study • Changes in important litter arthropods are reflected in spider populations • Litter spider populations tied to litter structure • Some native and exotic spiders may serve as indicators of changing woodland health Healthy Litter Layer Abundant Spider Activity in Healthy Litter Unhealthy Leaf Litter Under Buckthorn Earthworms obtained in one pit trap sample Impacts of Earthworms on Lier Microarthropods Typical density of Collembola (springtails) with earthworms present Density of Collembola (springtails) without earthworms present Pre-2000 Spider Records, by county" Source: J. Jass, 1998 (unpub.) • 494 species total • White = 0 • Green = 1-10 • Yellow = 11-50 • Orange = 51-100 • Red = >100 spp. Wolf Spider Crab Spider Orb-Web Spider Jumping Spider Palps: Male reproductive parts Male reproductive parts Cicurina robusta lateral palp Epigyne: Female reproductive parts. Linyphiid – Sheet web weaver Lycosidae – Wolf spiders Dime Linyphiidae (sheet web weavers) Neriene clathrata Male reproductive parts Pedipalps Genus: Bathyphantes Species: concolor Size: F = 2.3 -2.8 mm, M = 2.0 – 2.3 mm Centromerus corrnupalpis Ventral view Lateral view Female reproductive parts Ceraticelus fissiceps Linyphiidae (sheet web weavers) Walckenaeria atrotibialis Disembolus bairdi Eyes on raised cephalic region with pits Sheet web weaver Walckenaeria directa(Linyphiidae:Erigoninae) Banded pattern on abdomen may be complete Or broken with paired spots Genus: Agyneta Species: micaria Size: F = 2.0 - 2.5 mm, M = 2.0 – 2.5 mm Comments: One of the sheet web weavers. Salticidae" (jumping spiders) Phidappus audax Neon nellii 2.0-3.0 mm Naphrys pulex 4.0-5.5mm Jumping Spider Trapezoid sides of eye area parallel Tibia and metatarsi without dense hairs ventrally, ventral setae clearly visible Genus: Eris Species: militaris Size: F= 6.0 – 8.0 mm M= 4.7 – 6.7 mm Lycosidae (wolf spiders) Carapace with “V” shaped central spot between two broad dark bands Posterior median eyes large Trocanters with distinct rounded notch Genus: Pirata Species: minutus Size: F = 2.8 - 3.7 mm, M = 2.5-3.1 mm Comments: One of the wolf spiders. Carapace with two elongated spots in light band between two broad dark bands Wolf Spiders Epigynum of female with median Genus: Trochosa septum in shape of inverted “T” Species: terricola Size: F = 9.0 -14.0 mm, M = 7.0 - 9.0mm Carapace with two broad dark bands and a light central band Longitudinal piece of median septum widest posteriorly in female Epigynum Proximal end of tarsi I with long, stout dorsal spine Wolf Spider Genus: Schizocosa Brushy tibia of Species: ocreata male Size: F = 7.3 – 10.4 M = 5.7 – 8.3 mm Wolf Spider Carrying Egg Sac Carrying young on its abdomen Trochosa Ruricola Epigynum not wrinkled Tibia I with two pair of ventral spines Body covered with spatulate hairs, Thomisidae wider at the tip than at the base (crab spiders) Genus: Ozyptila Species: praticola Size: F = 4.0 mm, M = 3.0 mm Crab Spiders Body spines pointed, narrowing from base to tip Tibia I with three pair of ventral spines Genus: Xysticus Species: pellax Size: F = 6.3 mm, M = 3.5 mm Leg spots largest at the ends of the segments Carapace as wide or wider than long Philodromidae (crab spiders) Posterior median eyes further from each other than From the posterior lateral eyes Genus: Philodromus Species: vulgaris Size: F = 6.6 mm, M = 6.0 mm Median posterior eyes Oval and obliquely positioned Gnaphosidae (ground spiders) Terminal segments of spinnerets Long,cylindrical, or tubular in shape Cephalic and thoracic segments of carapace not distinctly separated Genus: Sosticus Species: insularis Size: F = 5.7 – 7.5, M = 4.6 – 5.9 mm Cephalic and thoracic Portions of carapace Not strongly differentiated Posterior eyes Subequidistant (almost equally spaced) Ground Spiders Distinct abdominal pattern Genus: Herpyllus Species: ecclesiasticus Size: F = 6.6 - 9.0 mm, M = 4.6 - 6.1 mm Corinnidae Dark carapace and abdomen (ant mimics) Abdomen with two distinct lines Dark bands on dorsal and lateral sides of femur Genus: Castianeira Species: cingulata Size: F = 7.2 – 7.3 mm, M = 4.3 – 4.4 mm Another ant mimic - front legs resemble antennae Phrurotimpus borealis Anyphaenidae (ghost spiders) Single pair metatarsal Two claws and claw tufts ventral spines Spiracular slit nearer to Epigastric furrow than in Anyphaena Genus: Aysha Species: gracilis Size: F = 6.4 - 7 mm, M = 5.7 - 6.5 mm Two claws and claw tufts Spiracular slit centrally positioned Metatarsus I with two pair of ventral spines Genus: Anyphaena Species: celer Size: F = 5.3 – 5.4 mm, M = 4.3 – 4.4 mm Clubionidae (sac spiders) Clubiona kastoni Clubiona maritima Pisauridae (nursery web weaver) Genus: Pisaurina Species: mira Size: F = 12.3-16.5mm M = 10.5-15.0mm Male palp Dyctinidae (mesh weaver spiders) Length of terminal segment of posterior spinneret less than the basal segment Genus: Cicurina Species: robusta Size: F = 5.8 – 9.1 mm, M = 5.0 – 6.7 mm Comments: Agelenidae (funnel web spiders) spinnerets Eye rows subequal Genus: Agelenopsis Species: pennsylvanica Size: F = 10-17 mm, M = 9-13 mm Funnel Web made by Agelinidae (Hahniidae) (dwarf sheet spiders) Horizontally placed spinnerets Neoantistea magna Orb Web Spider - Araneus sp. Classic Orb Web Dysderidae: (woodlouse spider) Number of adults trapped 10 15 20 25 30 35 40 0 5 6/26/98 7/10/98 7/24/98 8/7/98 8/21/98 9/4/98 9/18/98 10/2/98 Bathyphantes concolor Activity Bathyphantes concolor 10/16/98 10/30/98 11/13/98 11/27/98 12/11/98 Dates 12/25/98 1/8/99 1/22/99 2/5/99 2/19/99 3/5/99 3/19/99 4/2/99 4/16/99 4/30/99 5/14/99 5/28/99 6/11/99 Number of Individuals 10 12 14 16 0 2 4 6 8 6/26/98 7/10/98 7/24/98 8/7/98 8/21/98 9/4/98 9/18/98 10/2/98 10/16/98 ocreataActivity Schizocosa 10/30/98 11/13/98 11/27/98 Dates Dates 12/11/98 12/25/98 1/8/99 1/22/99 2/5/99 2/19/99 3/5/99 3/19/99 4/2/99 4/16/99 4/30/99 5/14/99 5/28/99 6/11/99 Number of Individuals 10 15 20 25 30 35 40 45 50 0 5 6/26/98 7/10/98 7/24/98 8/7/98 8/21/98 9/4/98 9/18/98 10/2/98 10/16/98 Cicurina Robusta Activity Cicurina Robusta 10/30/98 11/13/98 11/27/98 12/11/98 Date 12/25/98 1/8/99 1/22/99 2/5/99 2/19/99 3/5/99 3/19/99 4/2/99 4/16/99 4/30/99 5/14/99 5/28/99 6/11/99 Number of Individuals 0 1 2 3 4 5 6 7 6/26/98 7/10/98 7/24/98 8/7/98 8/21/98 9/4/98 9/18/98 10/2/98 10/16/98 Activity Oreanetides rotundus 10/30/98 11/13/98 11/27/98 12/11/98 Dates 12/25/98 1/8/99 1/22/99 2/5/99 2/19/99 3/5/99 3/19/99 4/2/99 4/16/99 4/30/99 5/14/99 5/28/99 6/11/99 Number of adults trapped 10 12 0 2 4 6 8 6/26/98 7/10/98 7/24/98 8/7/98 8/21/98 9/4/98 9/18/98 10/2/98 Gnathonoroides pedalisactivity Gnathonoroides 10/16/98 10/30/98 11/13/98 11/27/98 12/11/98 Dates 12/25/98 1/8/99 1/22/99 2/5/99 2/19/99 3/5/99 3/19/99 4/2/99 4/16/99 4/30/99 5/14/99 5/28/99 6/11/99 BATCON vs Richness 700 600 500 400 300 R² = 0.95685 200 Number of B.