1St Report Of A Twisted wing Insect (Strepsiptera) Larva In A Caddisfly

1 Pages·1993·0.33 MB·English

by  K L Manuel

Vol. 104,No. 3. May&June, 1993 139
FIRST REPORT OF A TWISTED-WING INSECT
(STREPSIPTERA) LARVA IN A CADDISFLY
(TRICHOPTERA)1
Kenneth L. Manuel,2Richard M. Bohart^
ABSTRACT:AmicrocaddisflyOxyethirajanella(Trichoptera: Hydroptilidae)wasobser-
vedwitha firststagestrepsipterantriungulinlarvainitsabdominalcavity.Thetriungu-
linidbelongstothegenusXenosorPseudoxenos(Strepsiptera:Stylopidae).Thisisthefirst
reportassociatingStrepsipterawithTrichoptera.
Whileidentifyingadultaquaticinsects,theseniorauthorremoveda
strepsipteran triungulin larva from the abdominal cavity of a female
microcaddisfly,Oxyethirajanella. TheO.janella specimenwascollected
bylight trap on the South Fork Edisto River, a Coastal Plain sand bot-
tomedblackwaterrivernearCope,OrangeburgCounty,SouthCarolina,
onOctober22, 1990.Subsequently,thejuniorauthoridentifiedthestrep-
sipteranasafirststagelarvaofeitherXenos, aPolisteswaspparasitoid,or
Pseudoxenos, a parasitoidofsphecid andeumenidwasps.The mounted
triungulin specimen is in the University ofCalifornia at Davis Insect
Museum.
Polistes wasp colonies are extremely common in the dense riparian
vegetationoverhangingthe South ForkEdistoRiver. Rovingtriungulin
larvaereleasedfromstrepsipteranparasitizedwaspsmaycomeintocon-
tactwithcaddisfliesandotherinsectsseekingdaytimeshelterinthelow
light, high humidity environment ofthe riparian vegetation.
TheO.janella specimen containingthe triungulinid in its abdomen
was probably incidentally "parasitized." Due to the relative short life
span ofmost caddisfly adults, a strepsipteran may not be able to com-
pleteitslifecycleinacaddisflyevenifitwerephysiologicallyadaptedto
mm
thehost'sbody.Inaddition,thesmall(1 long)abdomenofO.janella
may not allowthe complete development ofthe triungulin larva to an
adult.
Toourknowledge,noaquaticinsecthasbeenreportedasanormalor
incidental strepsipteran host. Aquatic entomologists, however, may
wishtolookforadditionalexamplesofstrepsipteran"parasitism"while
they are involved in adult aquatic insect identification.
ACKNOWLEDGMENTS
WethankRobertKelley(Greenville,SouthCarolina,USA)andAliceWells(Museum
andArtGalleriesofTheNorthernTerritory, Darwin,Australia) fortheircritical review
ofthe manuscript.
1 Received September29, 1922.AcceptedNovember7, 1992
2DukePowerCompany,AppliedScienceCenter.13339HagersFerryRoad,Huntersville,
NorthCarolina28078
3 DepartmentofEntomology,UniversityofCalifornia, Davis,California95615-8584
ENT. NEWS 104(3): 139. May&June, 1993