Genitalia observation technics

Chris J. Durden drdn at
Thu Nov 11 23:31:37 EST 1999

  In cases where hundreds of specimens must be examined genitalically it is
not necessary to make glass slides.
  Take the snapped off dry abdomen, or snipped of end of a squeezed fresh
abdomen; wet with ethyl alcohol; immerse in warm strong detergent water;
soak overnight if necessary.
  This washes out fats without degrading chitin, altering pigment pattern
or destroying any sphragis such as the one found in females of plebeiine
  The washed de-fatted portion with the genitalia is peeled and teased out
of the tergites not wanted in the preparation. The extracted genitalic
capsule may be examined under a binocular microscope. Valvae may be removed
if necessary. Processes may be tested for rigidity or flexibility.
Photographs or drawings may be made. 
  Upon completion the genitalic capsule and the other integument is
sterilized in ethyl alcohol and dried on a filter paper. The dried
dissection is stored in a gelatin capsule pinned directly under the
specimen from which it came and is readily available for the next
  This method may not be suitable for micros but it works well with
skippers. The riodinid transtilla may be mounted between two cover slips in
Permount or other suitable medium. The cover slip mount is held between a
mask cut from gummed label, and pinned under the specimen.
  Too many times I have seen wonderful but abdomen-free specimens, and
no-one could  find the slides that went with them.
.........Chris Durden

At 03:05  11/11/99 -0800, you wrote:
>We've been using techniques described in:
>Brown, J.W. & J.A. Powell. 1991(1992). Systematics of the Chrysoxena group
>of genera (Lepidoptera: Tortricidae: Euliini). Univ. Calif. Publ. Entomol.
v.111 pgs 14-15.
>Main exceptions are the substitution of Xylene with 95-100% Isopropyl
>alcohol, and the substitution of Canada Balsam with Euparal (avail from
>Bioquip, as is the Cellosolve). Only drawback with these substitutions is
>that Euparal takes far far longer to dry, and slides must be kept flat for
>months. Plus side is that it is far less carcinogenic than xylene. Here is
>the text (included because it is short):
>"The abdomen is removed by applying slight pressure to the venter and is
>placed in a solution of approximately 10% KOH. After about 24 hours the
>abdomen is transferred to water, and the macerated vicera are removed by
>flattening the abdomen dorsoventrally with a spatulate tool. For females,
>a longitudinal incision is made along the pleuron, and any remaining body
>contents removed. The genital capsule is then removed from the pelt by
>tearing the VIII-IX intersegmental membrane for males, and the VII-VIII
>intersegmental membrane for females. Both parts are transferred to
>cellusolve (Dowanol EE; C2H5OC2H4OH) for about 24 hours. The abdominal
>integument and genitalic capsule then are stained in a weak solution of
>chlorozol black. All items are washed in 95% EtOH and the aedeagus is
>removed. Males are transferred to xylene for 15-30 minutes, females to
>cellusolve, after which all parts are slide-mounted with Canada balsam."
>This technique is a variation of:
>Clarke, J.F.G. 1941. The preparation of the genitalia of 
>Lepidoptera. Bull. Brooklyn Entomol. Soc. 36:149-161.
>Powell, J.A. 1964. Biological and taxonomic studies on tortricine moths,
>with reference to the species in California. Univ. Calif. Publ. Entomol.
>Hope you find this useful.
>Jim Kruse
>University of California at Berkeley
>Dept. of Environ Sci, Policy and Mgmt.
>Div. of Insect Biology
>201 Wellman Hall
>Berkeley, California, 94720-3112
>Voice: (510) 642-7410    Fax: (510) 642-7428
>On Thu, 11 Nov 1999, Henri-Jérôme Bertin wrote:
>> I am looking for publications, papers, etc. that could help me preparing
>> genitalia. Can sombody give me a help?
>> Than you.

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