Protocols:

The following are the main protocols selected by the Diptera TWIG for the present project.

Protocol for Setting Up Malaise Traps and Handling Samples

Protocols for Culicidae (Darlene Judd)

Protocols for Ceratopogonidae (Art Borkent)

Protocols for Dolichopodidae (Daniel Bickel)

Protocols for Asilidae (Eric Fisher)

Protocols for Sarcophagidae (Thomas Pape)

Protocol for Acalyptratae (Stephen Marshall and Matthias Buck)


Protocols for Asilidae (Eric Fisher)

Habitat: Search for robber flies in a variety of habitats, but especially in areas with relatively undisturbed forest or other primary - or late secondary - growth vegetation. Asilids will be most abundant along edges of forest, where the denser vegetation opens - up into trails and small clearings.

The "tree - fall light gap" is a particularly rich habitat for Asilidae, and it deserves special attention during the Diptera inventory in Costa Rica. This habitat occurs where a live tree falls in dense forest, creating a small clearing or light gap (often one tree brings down several other trees or large branches as well). During the first 6 months or so, this light gap has intense robber fly (and other insect) activity, especially on the exposed sides of the fallen tree stems and larger branches, and on vegetation along the edges of the clearing. As the tree decays (starts to lose bark), and as emergent vegetation starts to cover or shade the stem of the fallen tree, this habitat ceases to be very productive for robber flies.

Collecting: The two main methods of collecting robber flies are: (1) hand collecting with a net; and (2) malaise trapping. (Occasionally Asilidae are taken at black lights; a few rare species have only been collected by this method.)

Placing malaise traps in tree - fall light gaps should be quite productive; place the trap adjacent to the fallen tree (or even on top of it). Forest edges are generally very good locations for traps also.

Preparation of Specimens: Use conventional methods to prepare robber fly specimens for study.

(1) Use paper points to mount smaller specimens (ca. <10 mm.), and pins for larger flies (ca. >10 mm.). Very slender Asilidae (e.g., Leptogaster) up to 15 mm. length should also be point - mounted.

(2) Use HMDS to dry small specimens collected in alcohol (those to be point - mounted). For larger flies in alcohol: first pin, then alcohol - dehydrate, then treat with ethyl acetate. Care should be taken so the wings are not allowed to dry in a position where their tips are too close to the top of the pin (otherwise they will be easily damaged).

 

Diptera TWIG / Sampling site selection /
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Protocols