''Gasteracantha cancriformis'' (spinybacked orbweaver) is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

orb-weaver spider Orb-weaver spiders are members of the spider family Araneidae. They are the most common group of builders of spiral wheel-shaped webs often found in gardens, fields, and forests. The English word "orb" can mean "circular", hence the English name ...

(family Araneidae). It is widely distributed in the

New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...

. The genus name ''Gasteracantha'' derives from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

words (', "belly") and (', "thorn"), while the

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

''cancriformis'' derives from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

words ' ("

crab Crabs are decapod crustaceans of the infraorder Brachyura (meaning "short tailed" in Greek language, Greek), which typically have a very short projecting tail-like abdomen#Arthropoda, abdomen, usually hidden entirely under the Thorax (arthropo ...

") and ' ("shape, form, appearance").

Description

Females are long and wide. The six abdominal spine-like projections on the abdomen are characteristic. The

carapace A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the unde ...

leg A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element cap ...

s, and underside are black with white spots under the

abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

. Variations occur in the colour of the upperside of the abdomen - a white or yellow colour with both featuring black spots. A white upper side can have either red or black spines while a yellow upperside can only have black ones. Like with many other spiders, males are much smaller (2 to 3 mm long) and longer than wide. All morphs have six abdominal spines. They are similar to the females in colour, but have a gray abdomen with white spots and the spines are reduced to four or five stubby projections. This species of

spider Spiders (order (biology), order Araneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude spider silk, silk. They are the largest order of arachnids and ran ...

does not live very long. In fact, the lifespan lasts only until reproduction, which usually takes place in the spring following the winter when they hatched. Females die after producing an egg mass, and males die six days after a complete cycle of sperm induction to the female.

Distribution and habitat

''G. cancriformis'' is native to North America, Central America, the Caribbean and South America. It has been introduced elsewhere, including Hawaii. It prefers living around the edge of woodland and shrubby gardens. Many studies about ''G. cancriformis'' are performed in citrus groves in Florida. ''G. cancriformis'' is seen to coexist within and on the edges of the colonies of other colonial orb-weaver spiders, mainly '' Metepeira incrassata''. ''M. incrassata'' is known to form large colonies ranging from few hundreds to few thousands of spiders, and their colonies often accommodate other species of orb-weavers including ''G. cancriformis''.

Taxonomy

''G. cancriformis'' has two subspecies, ''G. c. cancriformis'' and ''G. c. gertschi''.

Gallery

File:Close Up Of Spiny Orb Weaver Spider Eating a Butterfly.jpg, Eating a butterfly File:Gasteracantha cancriformis ventral.png, Ventral view, with

spinneret A spinneret is a silk-spinning organ of a spider or the larva of an insect. Some adult insects also have spinnerets, such as those borne on the forelegs of Embioptera. Spinnerets are usually on the underside of a spider's opisthosoma, and ar ...

visible File:Gasteracantha cancriformis in Miami.jpg, In

Miami Miami is a East Coast of the United States, coastal city in the U.S. state of Florida and the county seat of Miami-Dade County, Florida, Miami-Dade County in South Florida. It is the core of the Miami metropolitan area, which, with a populat ...

File:Gasteracantha cancriformis Miami.jpg, In Miami Lakes File:Gasteracantha cancriformis Quito, Ecuador.jpg, In

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

File:Gasteracantha cancriformis Novo Hamburgo.png, In

Novo Hamburgo Novo Hamburgo ('New Hamburg', ; ) is a Municipalities of Brazil, municipality in the southernmost Brazilian state of Rio Grande do Sul, located in the metropolitan area of Porto Alegre, the state capital. As of 2020, its population was 247,032. Th ...

(southern Brazilian population), with focus on the web File:Gasteracantha cancriformis mating in Summer.webm, Mating in the Summer File:Spiny Orb Weaver on Tufted Web.jpg, On a tufted web in Houston, Texas File:GasteracanthaCancriformisColorContrast.png, Color variation, near

Houston Houston ( ) is the List of cities in Texas by population, most populous city in the U.S. state of Texas and in the Southern United States. Located in Southeast Texas near Galveston Bay and the Gulf of Mexico, it is the county seat, seat of ...

File:UndersideOfOrangeGasteracanthaCancriformis.jpg, Underside of orange specimen, showing spinner and thread. For scale, band in background is 6 mm wide. Near

File:Gasteracantha cancriformis-female.jpg, In

Molokai Molokai or Molokai ( or ; Molokaʻi dialect: Morotaʻi ) is the fifth most populated of the eight major islands that make up the Hawaiian Islands archipelago in the middle of the Pacific Ocean. It is 38 by 10 miles (61 by 16 km) at its g ...

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

File:Gasteracantha cancriformis (Spinybacked orbweaver) - ventral view.jpg, Ventral view, in North Carolina

References

External links

{{Taxonbar, from=Q138490 cancriformis Spiders of North America Spiders of South America Spiders described in 1758 Taxa named by Carl Linnaeus Articles containing video clips