Fatal Attraction:

1. Fatal Attraction: Blister beetle larvae cooperate to practice mass deception in the Mojave Desert Leslie Saul-Gershenz Center For Ecosystem Survival J. Millar, U. C. Riverside

2. Mass Deception: A hitchhiker’s guide to the Mojave Desert Leslie Saul-Gershenz Center For Ecosystem Survival J. Millar University of California, Riverside

6. Larvae disperse & seek food Eggs laid in or near bee burrows Meloe larvaclimb onto vegetation Meloid Larva Morphology Cysteodemus Meloe Hornia

7. Meloe franciscanus& Habropoda pallida distribution Habropoda pallida Meloe franciscanus

9. Bee-witched and bee-lievable

23. Host finding behavior

26. Questions How do triungulin aggregations attract bees? Illicit signaling: 1. Visual mimicry: size, color, location, plant 2. Olfactory mimicry 3. Auditory mimicry

28. Visits to models, masses &dead bees

29. Visits & Hits visits hits mean(V/H) aggregations 98 5 obser. 2/<1 dead female 24 12 5/2=7 Live female 7 4 7/4=11 live female (caged) 125 0 19/1 hr Model of aggreg. 0 0 0 Dead male 0 0 0

30. Visual mimicry Bee Triungulins Size* 8.5 mm 8.38 mm P=.2448 Color gray-black red-brown Height 44.63 cm 28.13 cm 22-55 on plant 22-69 cm 10-55 cm overlap Plant perches overlap of species used *not sign.different (Mann-Whitney U test, U=157, Z=-1.163, P=.2448, n=20). Kolmogorov-Smirnov (goodness of fit) -distribution of aggregation lengths was significantly different than the distribution of female bee abdomen lengths. (n =20), DF=2, chi square =8.1, P<.05).

35. How to hitch a ride in the Mojave Desert Blister beetle larvae practice mass deception

37. Cooperative Aggressive Mimicry Behavior # observ. Mass stayed aggregated 27 events Mass moving up or down on plant stem 14 events Mass moved to different stem together 3 events Mass reformed after knocked down 4 events

38. Chemical profiles of female bees and triungulinsTo bee or not to bee Femalebee Triungulins

39. Host location system Blister beetle larvae practice mass deception 1. Triungulins emerge and aggregate. 2. Triungulins cooperate to mimic female H. pallida. 3. Triungulins attract H. pallida male to pseudocopulate and then attach en masse during contact. 4. Triungulins travel by phoresy on male bee and transfer to female bee via “venereal transmission.” 5. Triungulins reach bee nest via phoresy on female H. pallida. 6. Triungulins mimic female bees both visually and chemically.

40. Factors affecting the evolution of host location behavior in parasitoids Abundance and density of the host from the point of view of the parasitoid: Bees are a patchy, mobile resource. Annual abundance and distribution varies from year to year. Nectar source location is unpredictable because of dune habitat patchiness and heterogeneity. Human activities can disturb host plants (fire, grazing & soil compaction). Selection pressures on parasitoid and its searching behavior: Sand substrate temperatures reach 50˚ C. Larva have a greater risk of desiccation as an individual. Eggs at plant base are at risk of exposure from wind and shifting sand. Synchrony of intersection Host location window is affected by annual patterns of precipitation, temperature and wind. Bee nesting varies with Larrea bloom onset.

41. Kelso Dunes Sidewinder shelter Petalonyx Grasses Larrea Perching Perching Perching Herbivore Eggs Eggs Nectar/ pollen Nectar/ pollen Nectar/ pollen Nectar/ pollen predator Ecosystem Interactions Habropoda bee 30 species of bees Dasymutilla predator shelter shelter predator predator predator predator Metepiera spider Wilson’s warbler Crab spider Fringe-toed, leopard, brush Phiddipus spider

42. Science 1993-2000 Saul-Gershenz triungulins mimic bees 1895 Harrington large # triungulins on bees 1956 McSwain describes larvae as Meloe sp. A 28 years 54 years 33 years 18 years 26 years 1928 Van Dyke describes adult Meloe franciscanus from S.F 1841 Siebold recognizes phoretic relationship 1982 Pinto determines Meloe sp. A as M. franciscanus

44. Meloid History • 1700, Goedart was the first to associate the triungulin larvae of Meloe with adults • 1727 Frisch considered them to be lice and this error was perpetuated. • 1767 Linnaeus in Systema Naturae gave the name Pediculus apis. • 1828 Dufour described the genus Triungulinus for larvae of Meloe attached to an Andrena bee.Meloe triungulin claws in the form of a trident inspired Dufour to name his ‘bee louse’ Triungulinus • 1841 Seiboldrecognized the phoretic relationship between triungulin of Meloe & bees. • 1851 Newport definitely established that larvae of Meloe develop in the cells of bees • 1857 and 1859 Fabre observed the feeding behavior of the triungulin larvae in bee nests and applied the term hypermetamorphosis. • 1895 Harrington notes large numbers of triungulins on bees • 1928 Van Dyke describes Meloe franciscanus adult from SF • 1956 McSwaindescribes larvae,Meloe sp. A • 1982 Pinto identifies Meloe sp. A larvae as Meloe franciscanus. Adapted from Pinto & Selander 1970

45. Aggregation height vs. perching bee height • Venereal transfer • Bee bee contact Count

46. Kelso Dunes Petalonyx Grasses Larrea Perching Perching Eggs Perching Herbivore Eggs Ecosystem Interactions Nectar/ pollen Nectar/ pollen Nectar/ pollen Nectar/ pollen predator 30 species of bees Habropoda bee

50. Science 1993-2000 Saul-Gershenz triungulins mimic bees 1895 Harrington large # triungulins on bees 1956 McSwain describes larvae as Meloe sp. A 28 years 54 years 33 years 18 years 26 years 1928 Van Dyke describes adult Meloe franciscanus from S.F 1841 Siebold recognizes phoretic relationship 1982 Pinto determines Meloe sp. A as M. franciscanus