How hardy is a mite egg? Not hardy enough to with stand Vapona!
All jokes aside here is something that may be useful to you.
Life Cycle of the Snake Mite, _Ophionyssus natricis_
(For more information, see Camin, 1953)
The following chart gives the average span of time spent in each stage of
the snake mite's life cycle at two different temperatures. These
temperatures are the ends of the range commonly encountered in zoos.
Temperature
Development Stage 30 C (= 86 F) 20 C (= 68 F)
----------------- ------------- -------------
Egg 28 hours 98 hours
Larva (nonfeeding) 18 hours 47 hours
Protonymph (feeding) 3 days 14 days
Deuteronymph (nonfeeding) 13 hours 26 hours
Adult (feeding) 10 days 32 days
The time spent in the protonymph stage refers to those that find a host
soon after molt. Unfed protonymphs can live 15 to 19 days before dying of
starvation.
A gravid female leaves her reptilian host and finds a dark, moist crevice
where she lays eggs. Each egg hatches into a softbodied larva, which does
not move after leaving the egg. It is usually safe from dying of
dehydration in the crevice where it hatched. After molting into the
protonymph stage, the mite continues to stay in the humid crevice until its
exoskeleton becomes sclerotized, which minimizes the chance of death from
dehydration when the protonymph moves to dryer areas. Then it begins
wandering around the cage at random. If the protonymph encounters a host,
it climbs aboard, conceals itself under a scale, and begins feeding. When
full of blood, the protonymph drops off the host, finds a dark, moist
crevice, and molts into the deuteronymph stage. The deuteronymph is active
but usually remains in the crevice until the final molt into the adult
stage. The opposite sexes usually pair off in either the late proteronymph
or deuteronymph stage. Mating takes place shortly after the mites reach
adulthood. The adult wanders randomly around the cage until it encounters
a host. Then it climbs on the host, sucks blood until engorged, and drops
off. Males seek unmated females, and females seek crevices to lay eggs.
Females lay 60-80 eggs, feeding two or three times at intervals of one to
two weeks.
Whenever a mite encounters a barrier, it climbs instead of going around the
barrier. This leads mites to climb up the sides of the water dish, any
other cage furnishings, and the walls. Any mite that passes through an
opening and leaves the cage is likely to fall to the floor. There it
continues to wander randomly until it either dies or enters another cage
and finds a host. This wandering will rapidly infest every cage in the
area.
Snake mites have rather rigid behavior patterns. If they encounter a
barrier or an incline, they climb. They are attracted toward moist
conditions and toward dark areas. If cold, they are attracted toward
warmth until a threshold is reached, when they try to move toward a cooler
area. They are attracted by the smell of a host and tend to stop moving
when a contact area on the back touches something, like the underside of a
snake's scale. The groove along a snake's lower jaw and around its eye
make excellent attachment points for a mite, as these areas are adequately
warm, moist, and narrow enough to trigger the contact stimulus.
One of the natural dangers to a snake mite is its host shedding its skin.
The snake crawls away leaving the mite behind in the shed skin. However,
the snake is rapidly reinfested in the confines of a cage.
Drowning is another natural danger to a snake mite. Snake mites are not
able to swim and will eventually drown in water. In a bath, they are able
to migrate along a snake's body to the head, which is usually out of water,
and at least some of the mites survive. However, placing a clean snake
cage on legs in a shallow pan of water will prevent mites from just walking
into the cage.
Heat and dehydration are related dangers. Eggs are significantly less
likely to hatch successfully in dry conditions than in humid conditions.
Snake mites are killed within a few minutes at a temperature of 55 C (=
131 F).
(Camin, Joseph H. 1953. Observations on the life history and sensory
behavior of the snake mite, _Ophionyssus natricis_ (Gervais) (Acarina,
Macronyssidae). Chicago Academy of Sciences, Special Publ., No. 10. 75 pp.
I hope there was something here that could help.
Trevor