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Preparation of specimens for skeletonization by beetle larvae
A: Select large specimens to skeletonize.
B: Attach the branchial basket to the body of the specimen.
C: Delicious...
D: Hang filleted specimens high-up and if possible in sun and wind.
E: Expose to as much sun and wind as possible.
F: AMNH "Bug Room".
G: Vertebrate specimens being processed by dermestid beetle larvae.

Since the early 1920's museums have used dermestid beetle larvae to prepare skeletal specimens, and for a nice overview of the process download Sommer et al., 1974 here. In the following pages we outline the field procedures necessary for the preparation of specimens that can later be transformed into high quality fish skeletons by a beetle colony.

A) Large specimens are probably the most usefully skeletonized as small specimens can readily be cleared and stained for osteological examination. Additionally large specimens are likely to be fully ossified and are most easily processed in the field.

B) Remove eyes and all internal organs. During dissection remove as much fat as possible from the orbits and the abdomen. Remove the body and cheek musculature using a sharp scalpel. Cut as close as possible to each side of the fin pterygiophores, vertebral column and ribs, and if the scalpel blade becomes blunt replace it with a fresh one. Once all the flesh is removed from both sides of the fish, remove the gills and associated pharyngeal apparatus. Try to keep the entire branchial basket intact and once removed firmly attach it to the rest of the specimen with a piece of string passed through the pectoral girdle as shown below. NB: the "discarded" flesh is particularly delicious once wrapped in leaves of the family Marantaceae "au packet" and slowly roasted in the hot coals of a fire...

C) The filleted specimen will now need to be dried as rapidly as possible to prevent bacterial decay and/or infestation with maggots etc. If a ready source of alcohol is available (local rum or gin works well) the specimen should be immersed or doused in alcohol and hung (as high as possible to avoid "predation") in the sun and wind. If no alcohol is available just hang-up the specimen as soon as possible.

D) Exposure to as much sun and wind as possible is the best way to ensure that the specimens will not be degraded by decay so when moving around place the fish in an exposed place to accelerate drying.

E) Once the fish specimens are fully dried they will be rigid and hard. They can be wrapped in loose cheesecloth and sealed in multiple plastic bags and packed in liquapaks for shipment home

F) Before being placed in the beetle colony the field prepared specimens are immersed in alcohol for a few days, dried and stored in a freezer.

Some Congo fish skeletons
Auchenoglanis occidentalis (neurocranium)
Camplyomormyrus numenius
Chrysichthys delhezi
Labeo cf. lividus

© 2007 American Museum of Natural History Back to Ichthyology Department