Modelling the Putative Ancient Distribution of the Coastal Rock Pool Mosquito Aedes togoi

The coastal rock pool mosquito, Aedes togoi, is found in coastal east Asia in climates ranging from subtropical to subarctic. However, a disjunct population in the Pacific Northwest of North America has an ambiguous heritage. Two potential models explain the presence of Ae. togoi in North America: ancient Beringian dispersal or modern anthropogenic introduction. Genetic studies have thus far proved inconclusive. Here we described the putative ancient distribution of Ae. togoi habitat in east Asia and examined the climatic feasibility of a Beringian introduction into North America using modern distribution records and ecological niche modeling of bioclimatic data from the last interglacial period (~120,000 BP), the last glacial maximum (~21,000 BP), and the mid-Holocene (~6000 BP). Our results suggest that suitable climatic conditions existed for Ae. togoi to arrive in North America through natural dispersal as well as to persist there until present times. Furthermore, we find that ancient distributions of suitable Ae. togoi habitat in east Asia may explain the genetic relationships between Ae. togoi populations identified in other studies. These findings indicate the utility of ecological niche modeling as a complementary tool for studying insect phylogeography.

HOST IDENTIFICATION OF ARTHROPOD BLOODMEALS BY AGAR ELECTROPHORESIS*)

A relatively easy and inexpensive method of rapid gel electrophoresis suitable for the host identification of arthropod bloodmeals was investigated. Electrophoretic conditions (preparation of agar and buffer, voltage, temperature, time, etc.) are discussed. The method of preparing and applying the arthropod bloodmeal to the slides is discussed in detail. Two minutes after the start of the electrophoretic run the suitability of the arthropod meal for testing was apparent. When there was visible migration of more than one Hb fraction towards the anode, digestion has proceeded too far for host identification. Bloodmeals of Aedes togoi, Aedes aegypti, Culex fatigans, Anopheles sp., Rhodnius prolixus, Triatoma infestans, Triatoma dimidiata, Cimex lectularius, Pediculus humanus, Ornithodorus moubata, Ornithodorus savignyi and Ornithodorus rudis from man, Cebus and rhesus monkey, dog, cat, rabbit, guinea pig, hamster, rat, mouse, chicken, pigeon, snake, toad and frog were studied and compared with the serum and hemolyzed blood of the host species. It was possible to identify the host from the pattern of the arthropod bloodmeals. A number of details on arthropod digestion processes are given.