Geographic Range
Emperor scorpions,
Pandinus imperator
, are native to west Africa and are predominantly found in forests of Nigeria, Togo,
Sierra Leone, Ghana and the Congo region.
Habitat
Emperor scorpions are typically found in hot and humid forests. They reside in burrows
and prefer to live under leaf litter, forest debris, stream banks and also in mounds
of termites, their main prey. Emperor scorpions tend to live communally and are found
in large numbers in regions of human habitation.
- Habitat Regions
- tropical
- terrestrial
- Terrestrial Biomes
- forest
- Other Habitat Features
- estuarine
Physical Description
Emperor scorpions are one of the largest species of
scorpions
in the world, measuring an average of 20 cm in length. They also tend to be heavier
than other scorpions, and pregnant females can weigh more than 28 g. The body of the
emperor scorpion is shiny black in color with two huge pedipalps (pincers) in the
front, four legs and long tail (telson) ending in a stinger. Emperor scorpions have
special sensory structures called pectines behind their limbs for sensing features
of the terrain. Males usually have larger pectines than females. Like other
arthropods
, emperor scorpions undergo multiple molts. Their venom is mild and mainly used for
defensive purposes; they generally use thier huge claws to kill prey. Like other scorpions,
emperor scorpions give off a fluorescent bluish green appearance under UV light.
- Other Physical Features
- ectothermic
- venomous
- Sexual Dimorphism
- female larger
Development
Embryonic development of scorpions , including emperor scorpions, occurs in two ways, either apoikogenically or katoikogenically, and these methods differ in the amount of nutrition received from the mother. In apoikogenic development, ova have some yolk. Embryos use the yolk and receive some nourishment from the mother. In katoikogenic development, ova are without yolk, and embryos are nourished through a special feeding apparatus that develops early. Young embryos develop in the female ovariuterus or in specialized diverticula branching from the ovariuterus.
Most
scorpions
molt multiple times before becoming adults, though juveniles look like adults at
all instars.
Reproduction
Emperor scorpions conduct elaborate mating rituals. Usually, the male grasps the female
by pedipalps and engages in a myriad of behaviors including but not limited to sexual
stinging and cheliceral "kissing" before depositing the sperm. Like some other
arthropods
, female emperor scorpions may kill and consume the male after mating has occurred.
- Mating System
- monogamous
Emperor scorpions breed throughout the year. After a gestation period of on average
9 months, females give live birth to 10 to 12 young. Emperor scorpions reach sexual
maturity by 4 years of age.
- Key Reproductive Features
- year-round breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- viviparous
Emperor scorpions are born defenseless and rely heavily on their mother for food and
protection. Newborns are carried on their mother's back until they are old enough
to be on their own. Females are generally more aggressive after giving birth.
- Parental Investment
- female parental care
-
pre-fertilization
-
protecting
- female
-
protecting
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
protecting
- female
-
protecting
-
pre-independence
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
Emperor scorpions usually live 5 to 8 years in captivity. Lifespan is likely shorter
in the wild.
Behavior
Despite their fierce appearance, emperor scorpions are rather timid by nature (which
makes them popular as pets). Emperor scorpions are nocturnal and are rarely active
before nightfall. The locomotion of emperor scorpions is unusual in that they use
simultaneous extension of the femur-patella joint and the patella-tibia joint for
movement. When threatened, they usually flee rather than fight, but if cornered in
a small space, they turn aggressive and go into a defensive posture with their stinger
ready. Emperor scorpions are social animals and have been observed living in colonies
of up to 15 individuals. Cannibalism has been observed in this species, but it is
rare.
Home Range
Little information is available regarding the home range of emperor scorpions.
Communication and Perception
The eyesight of emperor scorpions is very poor. Their other senses are well developed,
with adaptations like the use of body hairs and pectines to detect the surrounding
environment and prey.
- Perception Channels
- visual
- tactile
- vibrations
Food Habits
Emperor scorpions typically eat
insects
and other
arthropods
and occasionally hunt down small vertebrates. They commonly eat
termites
. Adults generally do not kill their prey using their stinger but rather tear apart
prey using their powerful pincers. Juveniles, however, depend on their stingers to
kill prey.
- Primary Diet
-
carnivore
- eats terrestrial vertebrates
- eats body fluids
- Animal Foods
- mammals
- body fluids
- insects
- terrestrial non-insect arthropods
Predation
Emperor scorpions are eaten by many animals including
birds
,
bats
,
mammals
, and
spiders
.
Ecosystem Roles
Emperor scorpions eat a variety of
insects
and
arthropods
and are preyed upon by by
birds
,
bats
,
spiders
, and other mammals.
- Ecosystem Impact
- keystone species
Economic Importance for Humans: Positive
Emperor scorpions are popular in the pet trade, as they are timid and their venom
is mild. Many are imported for the pet trade from Ghana and Togo. They are often used
in movies because of their spectacular appearance. The venom of emperor scorpions
is also studied, as it is abundant in interesting peptides. A molecule called scorpine
has been isolated from the venom of Emperor scorpines. The scorpine molecule seems
to have anti-malarial and anti-bacterial qualities.
- Positive Impacts
- pet trade
- research and education
Economic Importance for Humans: Negative
The sting of emperor scorpions is generally mild and not fatal, but a pinch from their
pedipalps is known to be painful.
- Negative Impacts
-
injures humans
- bites or stings
- venomous
Conservation Status
Emperor scorpions are listed in Appendix II by CITES. Species listed in Appendix II
are not threatened, but trade is limited to prevent endangerment by human exploitation.
Emperor scorpions are collected for the pet trade and for scientific study.
Additional Links
Contributors
Cheryl Li (author), Rutgers University, Sahil Parikh (author), Rutgers University, David V. Howe (editor), Rutgers University, Gail McCormick (editor), Animal Diversity Web Staff.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- estuarine
-
an area where a freshwater river meets the ocean and tidal influences result in fluctuations in salinity.
- ectothermic
-
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
- venomous
-
an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).
- monogamous
-
Having one mate at a time.
- year-round breeding
-
breeding takes place throughout the year
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- internal fertilization
-
fertilization takes place within the female's body
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- female parental care
-
parental care is carried out by females
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- social
-
associates with others of its species; forms social groups.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- keystone species
-
a species whose presence or absence strongly affects populations of other species in that area such that the extirpation of the keystone species in an area will result in the ultimate extirpation of many more species in that area (Example: sea otter).
- pet trade
-
the business of buying and selling animals for people to keep in their homes as pets.
- venomous
-
an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).
- carnivore
-
an animal that mainly eats meat
References
Casper, G. 1985. Prey capture and stinging behavior in the Emperor Scorpion, Pandinus imperator (Koch) (Scorpiones, Scorpionidae). Journal of Arachnology , 13: 277-283. Accessed November 11, 2009 at http://www.americanarachnology.org/JoA_free/JoA_v13_n3/JoA_v13_p277.pdf .
Gaban, D. 2002. "Emperor Scorpions" (On-line). Accessed November 11, 2009 at http://home.mindspring.com/~drrod1/ .
Mahsberg, D. 1990. Brood care and family cohesion in the tropical scorpion Pandinus imperator (Koch) (Scorpiones: Scorpionidae). Acta Zoologica Fennica , 190: 267-272.
Montal, M. 2000. Scorpine, an anti-malaria and anti-bacterial agent purified from scorpion venom. FEBS Letters , 471: 165-168. Accessed November 11, 2009 at http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6T36-400W9P1-B-7&_cdi=4938&_user=526750&_orig=search&_coverDate=04%2F14%2F2000&_sk=995289997&view=c&wchp=dGLbVlb-zSkzV&md5=27cf84b2f34e431c1ac13a4c7aa3a121&ie=/sdarticle.pdf .
Pandinus, I. 2009. "The Story Behind Pandinus Imperator" (On-line). Accessed November 11, 2009 at http://www.pandinusimperator.nl/EN/story_EN.htm .
Rein, J. ed. 2009. "Pandinus imperator" (On-line). The Scorpion Files. Accessed November 11, 2009 at http://www.ntnu.no/ub/scorpion-files/p_imperator.php .
Ross, L. 2009. "Development and Care of Early-Instar Pandinus imperator" (On-line). Accessed November 11, 2009 at www.pandinusimperator.nl/EN/Earlyinstars.htm .
Rubio, M. 2008. Scorpions: Everything about Purchase, Care, Feeding, and Housing . US: Barrons Educational Series Inc. Accessed November 11, 2009 at http://books.google.com/books?id=N05C7CJUscoC&pg=PT32&lpg=PT32&dq=%22Commonly+Available+Scorpions%22&source=bl&ots=s81GHgs5Xa&sig=UwyExpLKOlhBn9rkeKsGExazSZg&hl=en&ei=o90qS9DLE4XP8Qb_y_2UBw&sa=X&oi=book_result&ct=result&resnum=3&ved=0CBQQ6AEwAg#v=onepage&q=%22Commonly%20Available%20Scorpions%22&f=false .
Shultz, J. 1992. Muscle Firing Patterns in two Arachnids using different methods of Propulsive Leg Extension. Journal of Experimental Biology , 162: 313-329. Accessed November 11, 2009 at http://jeb.biologists.org/cgi/content/abstract/162/1/313 .
theBIGzoo. 2009. "Emperor Scorpion (Pandinus imperator)" (On-line). theBIGzoo. Accessed November 11, 2009 at www.thebigzoo.com/Animals/Emperor_Scorpion.asp .
Oregon Zoo. 2005. "Oregon Zoo Animals: Emperor Scorpion" (On-line). Accessed November 11, 2009 at http://www.oregonzoo.org/Cards/Insects/emperor.htm .
2001. "Scorpion (Arachnid)" (On-line). Encyclopædia Britannica. Accessed November 11, 2009 at http://www.britannica.com/EBchecked/topic/529352/scorpion/47766/Internal-features .