The mosquitoes of Canada: Diptera, Culicidae (The Insects and arachnids of Canada)

398 Pages·1979·23.57 MB·English

by  D. M Wood

I-HE INSEOTS
AND ARAOHNIDS
OF CANADA
6
I?ART
The
uitoes
nada
Diptera' Culicidae
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F. R;,ette,
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THE INSECTS
AND ARACHNIDS
OF OANADA
PART 6
The
Mosquitoes
of Canada
Diptera' Culicidae
D. M. Wood, P. T. Dang,'and R. A. Ellis'?
Biosystematics Research Institute
Ottawa, Ontario
Research Branch
Asriculture Canada
Publication 1686 1979
I Research Associate, Carleton University, Ottawa, Ontaflo.
2 National Research Council Postdoctorate Fellow; presently Entomologist,
Parks and Recreation Department, Winnipeg, Manitoba.
O Minister of Supply and Services Canada 1979
Available in Canada through
Authorized Bookstore Agents
and other bookstores
or by mail from
Canadian Government Publishing Centre
Supply and Services Canada
Hull, Quebec, Canada K I A 0S9
Catalogue No. A 424211979-6 Canada: $8.00
ISBN 0-660-104024 Other countries: $9.60
Price subject to change without norice
The Insects and Arachnids of Canada
Part l Collecting, Preparing, and Preserving Insects, Mites, and Spiders,
compiled by J. E. H. Martin, Biosystematics Research Institute, Ottawa,
1977.
Part 2. The Bark Beetles of Canada and Alaska (Coleoptera: Scolytidae), by
D. E. Bright, Jr., Biosystematics Research Institute, Ottawa, 1976.
Part 3. The Aradidae of Canada (Hemiptera: Aradidae), by R. Matsuda,
Biosystematics Research lnstitute, Ottawa, 7977.
Part 4. The Anthocoridae of Canada and Alaska (Heteroptera:
Anthocoridae), by L. A. Kelton, Biosystematics Research lnstitute, Ottawa,
1978.
Part 5. The Crab Spiders of Canada and Alaska (Araneae: Philodromidae
and Thomisidae), by C. D. Dondale and J. H. Redner, Biosystematics
Research Institute, Ottawa, 1978.

Contents
Introduction. 7
General biology........... 9
Geographic distribution 21
Phenology 26
Anatomy 28
Methods of collecting, rearing, and preserving mosquitoes 45
Synonymy and authorship 54
Acknowledgments....................... 56
li c"""J"-"J"r,t
Key to the genera of mosquitoes 57
Key to the genera of mosquitoes of Canada-larvae 6l
Subfamily Anophelinae ...:... . ... 65
Genus Anopheles Meigen 65
Key to the species of Anopheles of Canada-adults .... ... ... .. . . . 68
Key to the species of Anopheles of Canada-fourth-instar larvae ... .. 70
Subfamily Toxorhynchitinae ................ 90
Genus Tox o rhy nc hi t e s Theobald 90
Subfamily Culicinae........ 94
Genus Aedes Meigbn 94
Subgenera of Aedes 95
Key to the species ol )n'irl ot i^".J"-"Jtrt females 95
Key to the species of Aedes of Canada-adult males 104
Key to the species of Aedes of Canada-fourth-instar iarvae . .. . ... ... .. . . 113
Genus Culex Linnaeus 272
Key to the species of Culex of Canada-adults,.. . ... . . . .. . .. 272
Key to the species of Culex of Canada-fourth-instar lawae ..... ... ... ... 273
Genus Culiseta Felt ...... ..... 286
Key to the subgenera and species of Culiseta of Canada-adults ..... ... 287
Key to the subgenera and species of Culiseta of Canada-fourth-
instar Iarvae.......... 290
Subgenus Culiseta Felt 291
Subgenus Climacura Howard, Dyar, & Knab 303
Subgenus Culicella Fe1t................ 306
G enus M a n s o ni a Blanchar d JIJ
Genus Orthopodomyia Theobald ..... 319
Key to the species of Orthopodomyia of Canada-adults . . .. ... ...... ... . .. . 320
Key to the species of Orthopodomyia of Canada-fourth-instar
larvae 320
G enus P s orop ho ra Robineau-Desvoidy 327
Key to the subgenera and species of Psorophora of Canada-adults .. 328
Key to the subgenera and species of Psorophora of Canada-
fourth-instar Iarvae............. 329
Gents Uranot aenia Lynch Arrib|lzaga
. .
Gents Wyeomyia Theobald 343
Canada
Species potentially occurring in or incorrectly recorded from 348
Glossary
351
References ..
362
Index
387
.
Table 3......... foldout
lntroduction
Throughout Canada mosquitoes are familiar to everyone as biting
pests. In addition to their importance as a nuisance, a few species occasion-
ally create problems out of all proportion to their numbers by transmitting
disease organisms. Such pests have been the reason for costly abatement
programs. At times, Canada seems to have been afflicted with a greater
than average share of mosquitoes. Though the number of species (so far, 74
have been found) is not particularly large compared with the fauna of
tropical countries, mosquitoes are often exceptionally numerous, and almost
every part of the country experiences periodic outbreaks of one species or
another.
An important step in successful mosquito abatement, as in dealing with
any pest problem, is the correct identification of the offending species.
Entomological history contains many examples of wasted money and effort
because some similar but innocent species was mistaken for the pest species.
Some of the most abundant widespread species of mosquitoes exhibit
variation in color, and even in structure, across their ranges. This intras-
pecific variation along with extreme similarity of closely related species.
especially among some Aedes and Culex, makes correct identification
difficult, particularly of adult females. In difficult cases, adults reared from
previously identified larvae can be named with much greater assurance than
either larvae or adults identified separately. For example, adult females of
Aedes euedes,fitchii, and mercurator are extremely similar, as are adults of
both sexes of Aedes aboriginis and punctor, although their larvae are readily
distinguishable. However, the larvae of Aedes cornmunis, implicatus, and
stimulans are not readily separable, although the adults are more easily
distinguished.
This publication has been prepared for the identification of adults and
fully grown larvae. Although eggs, early instar larvae, and pupae of most
North American species are known, they are less easily identified than
adults and mature larvae. Also, sufficient material for every species and
enough experience to offer identification aids for these early stages are
lacking. Rearing eggs and pupae to larvae and adults is probably easier and
less time consuming than attempting to identifiy them in their early stages.
In this publication, the keys to the larvae differ somewhat from the
traditional approach, because they are specifically designed for identifying
whole specimens in fluid, either alive or preserved, with the aid of a
dissecting microscope. The identification of living larvae can be confirmed
by rearing them to the adult stage.
Eggs of many species of Aedes have been illustrated by Kalpage and
Brust (1968). For the identification of first-instar larvae the reader is
referred to Bohart (1954), Price (1960), and Dodge (1966); for second and
third instars to Dodge (1963) and Smith (1969a); and for pupae to Penn
(1949) and Darsie (1949,1951, 1955, 1957).
The following keys describe the usual, or "normal," condition based on
a series of each species in the Canadian National Collection. However, every
structural character in both adults and larvae shows some individual or
regional variation; in most cases this variation has not been described in the
literature. Such variations are usually minor, but the examination of enough
specimens of any species usually shows a few individuals whose taxonomic
characters do not conform to those used in the keys. These specimens, which
can best be identified by direct comparison with more typical specimens, are
most likely aberrant individuals of species already recorded from Canada,
but they could also belong to species known from the northern United States
that have not yet been discovered in Canada. These latter species, which are
listed in a later chapter, can be identified by referring to Carpenter and
LaCasse (1955). This standard work has been brought up to date by a series
of three supplements (Carpenter 1968, 1970b, 1974) and a summary of
taxonomic changes (Darsie 197 3, 1978).
When a specimen has been keyed out, it should be compared with the
description of that species. The descriptions contain more information than
can be included in the key and are therefore provided as a cross-check. The
descriptions of the adults follow a standard format. The larval descriptions
are abbreviated to include only those characters that, taken together,
characterize a particular species; more complete information on larval
characters is summarized in Table 3 (foldout).
Generalizations have been necessary in the keys and in the descriptions
of species as well as in the presentation of biological information. A given
species may behave predictably for many years, but then it "breaks the
rules" as a result of some unusual set of environmental circumstances. Some
of the common widespread species may be complexes of more than one
species, not yet separable by external structures, but having different habits
or behavior. Widespread species also encounter differing environmental
conditions across Canada, and as a result they may behave differently in
different parts of the country. The amount of literature on mosquitoes is
enormous, and some reports are even contradictory, which makes generali-
zations hazardous.