Geographic Range
Diamanus montanus can be found in North America, west of the Rocky Mountains in the United States and Mexico (Hubbard, 1968; Lawson, 1982; Pan American Health Organization, 1965). More specifically, it can be found in the Pacific Coastal and Rocky Mountain region along with Colorado, Utah, Arizona, New Mexico and also south to Michoacan and Edo. de Mexico, Mexico (Traub, 1983).
Habitat
Diamanus montanus usually lives in the nests of ground squirrels located in a non-urban setting (Young, 1982) and is rarely found feeding on other rodents (Hubbard 1968). Nests inhabited by fleas may include twigs and leaves or even cotton or upholstery stuffing (Beard, 1992).
- Habitat Regions
- temperate
- terrestrial
- Terrestrial Biomes
- savanna or grassland
- chaparral
- forest
- scrub forest
- mountains
Physical Description
This is a dark brown flea. Adults are medium-sized compared to most fleas. This species has particularly long palps (Ebeling, 2002).
Male and female
D. montanus
are sexually dimorphic with males having a rounded clasper that is pushed ventrally.
There are two long, strong bristles and four weak bristles near the finger and clasper.
The finger of
D. montanus
forms a curved blade-like shape, which has 11 bristles. In females, the spermatheca
has a bit of a bulging body and a crooked tail (Hubbard, 1968). The spermatheca also
shows a ventral contriction between the bulga and hilla. The anal stylet normally
has one long ventral seta and no dorsal seta. In males, sternum VIII is without setae
(Traub et al., 1983).
Eggs are large (around 0.5 mm). Larvae are white, legless, eyeless and are sensitive
to humidity. Pupae spin silk cocoons.
- Other Physical Features
- ectothermic
- heterothermic
- bilateral symmetry
- Sexual Dimorphism
- female larger
Development
Fleas have holometabolous metamorphosis (larval, pupal, and adult stages).
- Development - Life Cycle
- metamorphosis
Behavior
Diamanus montanus was found to be most abundant on ground squirrels at lower than 18.44°C temperatures. (Lang, 1996). The hosts (squirrels) may become infected with plague from the flea after hibernation and after returning to burrows. (Lang, 1996)
Fleas are nidicolus parasites; they get on the host and immediately feed and then
quickly get off. Their ability to quickly get on and off the host is aided by their
impressive jumping mechanism. (Roberts, 2000)
- Key Behaviors
- saltatorial
- parasite
- motile
- sedentary
- solitary
Food Habits
Diamanus montanus
is a parasite that feeds mainly on the blood from ground squirrels in the genus
Spermophilus
(Hubbard, 1968). Some specific examples of ground squirrels carrying
D. montanus
are the California ground squirrel,
Spermophilus beecheyi
(Lang, 1996) and
S. variegatus
(Traub et al., 1983).
Diamanus montanus
has a proventriculus that facilitates the break down of the rodent blood meal injested
by the flea. If the flea is infected by the plague-causing bacteria,
Yersinia pestis
, the bacteria will multiply and block the proventriculus. When the flea tries to
feed, the host blood can not pass through the proventriculus and a blood and bacteria
mixture go back into the host causing the host to become infected with the plague
bacteria. Even though fleas can survive long periods of time without food, they will
eventually die from starvation because the flea can no longer feed (Roberts & Janovy
2000).
- Primary Diet
- carnivore
Ecosystem Roles
These fleas are ectoparasites on their hosts, feeding on blood. They sometimes transfer diseases to their hosts as well.
- Ecosystem Impact
- parasite
- California ground squirrel ( Spermophilus beecheyi )
- Spermophilus variegatus
- ground squirrels in the genus Spermophilus
Economic Importance for Humans: Negative
Diamanus montanus is one of the North American vectors for the pathogen Yersinia pestis , the plague bacillus. Other flea species can transmit the disease as well. Plague is mainly a disease of rodents, but humans may also become infected through a bite from an infected flea. Diamanus montanus is a vector for the spread of campestral plague ("plague in the countryside," as opposed to plague in cities) in the western United States. D. montanus has been shown to be only a moderately effective vector, which is not very likely to transmit the bacteria even if it bites a human.
Many people are unaware that bubonic plague still exists in the United States, but
every year a few Americans become infected with the bacteria, which now can be treated
with antibiotic drugs.
Y. pestis
infections are more common in particular regions of the world, such as certain parts
of the western U.S., where the right combinations of climate, rodents, and fleas allow
the disease to persist in wild rodent populations. While this disease does not currently
pose a major threat to North American populations, it remains present, and public
health agencies in parts of the continent where it exists do monitor it to prevent
epidemics.
- Negative Impacts
-
injures humans
- bites or stings
- carries human disease
Conservation Status
This species is fairly abundant in its range, and is not believed to be in need of conservation.
Additional Links
Contributors
George Hammond (editor), Animal Diversity Web.
Linda Hemeyer (author), University of Michigan-Ann Arbor, Solomon David (editor), University of Michigan-Ann Arbor.
- Nearctic
-
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- tropical savanna and grassland
-
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
- savanna
-
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
-
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
- chaparral
-
Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- scrub forest
-
scrub forests develop in areas that experience dry seasons.
- mountains
-
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- heterothermic
-
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- metamorphosis
-
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
- saltatorial
-
specialized for leaping or bounding locomotion; jumps or hops.
- parasite
-
an organism that obtains nutrients from other organisms in a harmful way that doesn't cause immediate death
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- solitary
-
lives alone
- parasite
-
an organism that obtains nutrients from other organisms in a harmful way that doesn't cause immediate death
- carnivore
-
an animal that mainly eats meat
- sanguivore
-
an animal that mainly eats blood
References
Beard, M., G. Maupin, R. Craven, C. Montman, A. Barnes. 1992. Laboratory and field trials of permethrin-treated cotton used as nesting material to control fleas (insecta: Siphonaptera) on cricetid rodents. Journal of Medical Entomology , 29(2): 338-342.
Ebeling, W. 2002. "Urban Entomology" (On-line). Accessed December 03, 2004 at http://www.entomology.ucr.edu/ebeling/ .
Hubbard, C. 1968. Fleas of Western North America . NY: Hafner Publishing Co..
Lang, J. 1996. Factors affecting the seasonal abundance of ground squirrel and wood rat fleas (Siphonaptera) in San Diego County, California. Journal of Entomological Society of America , 33(5): 790-804.
Roberts, L., J. Janovy, Jr.. 2000. Foundations of Parasitology . McGraw-Hill Higher Education.
Russel, H. 1913. The Flea . London: Cambridge University Press.
Rutledge, L., M. Lawson, L. Young. 1982. Tests of repellents against *Diamanus montanus* (Siphonaptera: Ceratophyllidae). Journal of Medical Entomology , 19: 361-365.
Traub, R., M. Rothschild, J. Haddow. 1983. The Rothschild Collection of Fleas. The Ceratophyllidae: Key to genera and host relationships . London: Academic Press Inc..
Weniger, B., J. Warren, V. Forseth, G. Shipps, T. Creelman. 1984. Human bubonic plague transmitted by a domestic cat scratch. Journal of the American Medical Association , 251: 927-929.
Pan American Health Organization. Plague in the Americas. Scientific Publication #115. Washington, District of Columbia, USA: 1965.