Checklist of the Collembola: Methods |
Frans Janssens, Department of Biology, University of Antwerp, Antwerp, B-2020, Belgium
Culturing: Collembola can be kept on moist soil or peat moss, but they thrive best and are most useful when cultured in small jars on a plaster of Paris/powdered charcoal substrate kept moist with aged tap water. They are fed baker's yeast. They should be fed and watered at least once per month.
Optical microscopy preparation protocols:
Preserving: Specimens may be stored in 70-95% ethanol or 70% isopropanol with 1% glycerol. They should have been kept in the preservative for at least 2 weeks before examination in a clearing fluid (Christiansen in Dindal, 1990:968). Individual specimens should be manipulated with care using a quite flexible pincer, such as a Leonard pincet. The smallest specimens are handled using a very fine brush.
Clearing:
Preserved specimens can be cleared in Marc André 1 medium
(distilled water 30 cm3,
chloral hydrate 40 g,
glacial acetic acid 30 cm3).
Fresh specimens are likely to 'explode', although this is often good
for displaying chaetotaxy.
Specimens are kept in this medium until cleared.
Specimens can be safely kept in Marc André 1 medium as long as 36 hours.
Very dark specimens may have to be depigmented first in kalium hydroxide (KOH)
or hydrogen peroxide (H2O2)
(Christiansen in Dindal, 1990:968).
Specimens can also be cleared in Nesbitt's fluid (Wang et al., 2003:603)
(distilled water 25 cm3,
chloral hydrate 40 g,
1N hydrogen chloric acid (HCl) 2.5 cm3).
For clearing specimens from old ethanol collections
see Daghighi & al (2016).
Mounting:
In Marc André 1 cleared specimens can be mounted on microscopic slides in
Marc André 2 medium
(distilled water 50 cm3,
gum arabic 20 g,
chloral hydrate 200 g,
glycerine 40 cm3)
(Christiansen in Dindal, 1990:968).
In Nesbitt cleared specimens can be mounted in Hoyer's medium (Wang et al., 2003:603)
(distilled water 50 cm3,
gum arabic 30 g,
chloral hydrate 200 g,
glycerine 16 cm3).
Scanning Electron Microscopy preparation protocols:
For an introduction to sample preparation for SEM,
see
Sample Preparations for Scanning Electron Microscopy - Life Sciences
by Mogana Das Murtey & Patchamuthu Ramasamy (2016).
Distinguishing Collembola from similar sized Arthropoda: to be completed.
Identifying:
Identification of a specimen is best done using a phase contrast
compound microscope.
Identifying a specimen involves a hierarchical process of keying out
the family, then the genus
and finally the species of the specimen under investigation
(see the
icons in the systematic lists for currently available taxon specific keys).