Trypoxylon tridentatum
Packard, 1867
Species Guides
2Trypoxylon tridentatum is a spider-hunting in the Crabronidae, subgenus Trypargilum. It inhabits mesic and xeric in arid regions, particularly the Baja California peninsula. The wasp provisions nest with paralyzed spiders as food for its larvae, showing strong preference for orb-weaving spiders in the family Araneidae. Unlike its T. politum, which constructs free-standing mud nests, T. tridentatum nests in pre-existing cavities such as hollow twigs, borings, and abandoned mud dauber nests.
Pronunciation
How to pronounce Trypoxylon tridentatum: /trɪˈpɒksɪlən ˌtraɪdenˈtɑːtəm/
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Distinguished from other Trypoxylon by larger size (subgenus Trypargilum vs. Trypoxylon). Separated from T. politum by nesting : T. tridentatum uses pre-existing cavities rather than constructing free-standing mud tubes. Distinguished from other Trypargilum by geographic distribution and prey composition; definitive identification requires specimen examination. and single forewing submarginal separate from other crabronid .
Habitat
Mesic and xeric in arid regions, specifically oases in desert environments. Occupies areas with sufficient moisture to support spider while maintaining overall arid conditions. Nests in pre-existing cavities including hollow twigs, dead standing trees with borings, vacated insect galls, and abandoned mud dauber nests.
Distribution
Baja California Sur, Mexico; specifically documented from oases in the arid Baja California peninsula. Broader distribution in western North America likely but not well-documented in provided sources.
Diet
Spiders (Araneae), primarily individuals. Araneidae (orb-weavers) constitute 60.9% of prey, including Eriophora , Araneus lineatipes, Kaira alba, and Metepeira crassipes. Theridiidae (Theridion submissum) and Mimetidae also significant. Additional include Dictynidae, Anyphaenidae, Salticidae, Uloboridae, Tetragnathidae, Miturgidae, and Philodromidae. Prey composition varies between xeric and mesic .
Host Associations
- Eriophora sp. (Araneidae) - preyMost frequent prey in xeric (29.0%)
- Theridion submissum (Theridiidae) - preyMost common prey in mesic (21.1%)
- Metepeira crassipes (Araneidae) - prey16.5% of prey
- Araneus lineatipes (Araneidae) - preyNew record for Baja California
- Kaira alba (Araneidae) - preyNew record for Baja California
- Philoponella arizonica (Uloboridae) - preyNew record for Baja California
- Uloborus segregatus (Uloboridae) - preyNew record for Baja California
- Mimetidae - prey-level prey record
- Dictynidae - preyCaptured only in mesic
- Anyphaenidae - preyCaptured only in mesic
- Salticidae - preyCaptured only in mesic
- Tetragnathidae - preyCaptured only in mesic
- Miturgidae - preyCaptured only in mesic
- Philodromidae - preyCaptured only in mesic
Life Cycle
Solitary nesting in pre-existing cavities. Female progressively partitions tunnel into individual from back to front, provisioning each with 5-20 paralyzed spiders (range 3-36). Single laid in each cell on last spider provided. Larva consumes paralyzed spiders, then spins -specific cocoon of silk, saliva, and soil. Pupa overwinters inside cocoon; emerges weeks later or following spring.
Behavior
Females hunt spiders and paralyze them with venom, transporting them to nest. Males guard nest entrance during female absence, blocking and rival males. Males may assist by receiving prey from females, cleaning cavities, and helping construct partitions and terminal mud plug. Some pairs demonstrate cooperative 'patriarchate' with shared nest maintenance duties.
Ecological Role
controlling spider , particularly orb-weavers. Contributes to dynamics in oasis . Prey selectivity differs between xeric and mesic , potentially influencing local spider structure. Serves as for parasitic insects (implied by male guarding ).
Human Relevance
Potential agent for spider . Could be supported through provision: drilling holes (1/4 inch to 3/16 inch, 77-124 mm deep) in wood blocks creates nest sites. No negative impacts documented; solitary and non-aggressive.
Similar Taxa
- Trypoxylon politumAlso large, black, with possible white leg markings, but constructs distinctive free-standing mud tube nests rather than using pre-existing cavities
- Trypoxylon californicumSimilar size and subgenus (Trypargilum), but different geographic range and prey preferences (jumping spiders, crab spiders, lynx spiders, sac spiders)
- Trypoxylon clavatumCongeneric with similar ; distinguished by subtle morphological differences requiring specimen examination
- Pachodynerus nasidensAlso called 'keyhole wasp' and nests in cavities, but in Vespidae with different body proportions and wing venation
More Details
Prey Diversity
Nineteen spider and three were newly recorded as prey for this in the Baja California study, expanding known prey range significantly.
Habitat-Dependent Prey
Prey composition differs markedly between xeric and mesic , with certain spider (Dictynidae, Anyphaenidae, Salticidae, Uloboridae, Tetragnathidae, Miturgidae, Philodromidae) captured exclusively in mesic conditions.
Taxonomic Note
The T. tridentatum tridentatum was described by Packard in 1867; full status may apply to broader T. tridentatum sensu lato.
Sources and further reading
- BugGuide
- GBIF taxonomy match
- iNaturalist taxon
- Catalogue of Life
- Bug Eric: Wasp Wednesday: Trypoxylon
- Bug Eric: Pipe Organ Mud Dauber, Trypoxylon politum, Found in Colorado
- Bug Eric: Mud Masterpieces
- Bug Eric: August 2015
- Composition of spider prey captured by the waspTrypoxylon(Trypargilum)tridentatum tridentatumin two habitats in an oasis in Baja California Sur, Mexico