Laboratory rearing of the squirrel fleaCeratophyllus sciurorum sciurorum with notes on its biology

A rearing method for the fleaCeratophyllus (Monopsyllus) sciurorum sciurorum, a pest on farmed mink in Europe, has been developed. The behaviour of egg-laying and the development period are described at 23 °C and 80% r.h. The eggs ofC. sciurorum sciurorum hatched after 4–7 days and cocoons were formed 10–12 days later. The development period from egg to newly emerged adult was 23–32 days. Females emerged, in general, earlier than males.     

Contrasting seasonal dynamics in fleas of the Siberian flying squirrel (Pteromys volans) in Finland

Abstract.  1. The seasonal and spatial variation of the adult flea fauna (Siphonaptera) was examined in connection with live-trapping studies of the Siberian flying squirrel ( Pteromys volans ) in three study areas in southern Finland between 1997 and 2005.
2. The numerically dominant flea species of the Siberian flying squirrel were Tarsopsylla octodecimdentata octodecimdentata and Ceratophyllus (Monopsyllus) indages indages (Ceratophyllidae); the latter being a host specialist of the Siberian flying squirrel. Tarsopsylla octodecimdentata , which also commonly occurs on the red squirrel ( Sciurus vulgaris ), infected a large proportion of the host population throughout the winter, whereas C. indages occurred predominantly during the summer and autumn, being practically the only flea species in nests during the flying squirrels' breeding season and on juveniles still inhabiting their natal nest.
3. The use of nest boxes by flying squirrels did not have any positive effects on flea populations, but it may have had a negative impact on T.   octodecimdentata .
4. The potentially vulnerable C.   i.   indages is a predictable, widespread component in the flea fauna of the Siberian flying squirrel at various spatial scales, and it is likely to occur in most of the permanent flying squirrel populations in Finland.     

A circadian rhythm of locomotor activity in newly emerged Ceratophyllus sciurorum

Abstract Circadian rhythm in newly emerged individuals of the Red Squirrel ( Scuirus vulgaris ) flea C.s. sciurorum was studied in a constant environment, using an insect activity monitor. Trials were run over 7 days using two start times (08.00 and 17.00 hours). The results show that, regardless of start time, the fleas display a 24 h activity rhythm. The presence of a rhythm under constant conditions gives a strong indication that C. s.sciurorum has a self-sustaining clock which is started by disturbance and is most likely to be linked to host activity patterns.     

On the fleas and louse (Insecta: Siphonaptera and Anoplura) of the garden dormouse,Eliomys quercinus (L. 1766) in Belgium

More than 3500 fleas, collected in southern Belgium, from 54 garden dormice (Eliomys quercinus) and from 58 nests of the rodent, were examined. Ceratophyllus s. sciurorum seems to be the only regular and abundant flea on the garden dormouse and in its nest whereas Myoxopsylla laverani is quite uncommon (5/31 infested animal and 11/52 infested nests). In comparison, 96 garden dormice were checked in France. M. laverani is present on nearly every infested animal (61/66). Other fleas were also found, some mammal-fleas (Megabothris turbidus, Hystrichopsylla talpae, several Ctenophthalmus spp.) and great numbers of bird-fleas (Ceratophyllus gallinae and Dasypsyllus gallinulae) because the dormouse-nests where the fleas were taken were built on old tit-nests (Parus spp). Finally, Schizophthirus pleurophaeus, a louse, was collected for the first time in Belgium.