Micrathena, known as spiny orbweavers, is a
genus of
orb-weaver spiders first described by
Carl Jakob Sundevall in 1833.[5][6]Micrathena contains more than a hundred species, most of them
Neotropical woodland-dwelling species. The name is derived from the Greek "micro", meaning "small", and the goddess
Athena.[7]
Species with extremely long spines evolved at least eight times in the genus Micrathena and likely function as anti-predator defenses.[8]Gasteracantha orb-weavers also have hardened abdomens with variously shaped spines, but they are not closely related to Micrathena within the orb-weaver family.[9]
These spiders are active during the daytime and build vertical orb webs. Unlike many other orb-weavers, members of Micrathena bite their prey before wrapping it. When laying eggs, females will place the egg sac on vegetation near the web.[5]
Species
As of April 2019[update] the genus Micrathena contains 119 species:[1]
Although the genus includes over a hundred species, only four are found in the United States and Canada.[10] Among those four species, female spined micrathena (Micrathena gracilis) have five pairs of conical
tubercles, female M. mitrata have two short posterior pairs, and female arrow-shaped micrathena (M. sagittata) have three pairs.[5] Only two species are recorded from Canada, being M. sagittata, found primarily in the
Pinery Provincial Park, and M. gracilis, which is more widespread.[5][11]
^Magalhaes, I. L. F.; Santos, A. J. (2012). "Phylogenetic analysis of Micrathena and Chaetacis spiders (Araneae: Araneidae) reveals multiple origins of extreme sexual size dimorphism and long abdominal spines". Zoological Journal of the Linnean Society. 166: 29.
^Levi, H. W. (1985). "The spiny orb-weaver genera Micrathena and Chaetacis (Araneae: Araneidae)". Bulletin of the Museum of Comparative Zoology. 150: 440.
^Scharff, N. (1991). "On the synonymy of Thaumastobella mourei Mello-Leitão and Ildibaha albomaculata Keyserling (Araneae, Araneidae)". Journal of Arachnology. 19: 155.
Micrathena, known as spiny orbweavers, is a
genus of
orb-weaver spiders first described by
Carl Jakob Sundevall in 1833.[5][6]Micrathena contains more than a hundred species, most of them
Neotropical woodland-dwelling species. The name is derived from the Greek "micro", meaning "small", and the goddess
Athena.[7]
Species with extremely long spines evolved at least eight times in the genus Micrathena and likely function as anti-predator defenses.[8]Gasteracantha orb-weavers also have hardened abdomens with variously shaped spines, but they are not closely related to Micrathena within the orb-weaver family.[9]
These spiders are active during the daytime and build vertical orb webs. Unlike many other orb-weavers, members of Micrathena bite their prey before wrapping it. When laying eggs, females will place the egg sac on vegetation near the web.[5]
Species
As of April 2019[update] the genus Micrathena contains 119 species:[1]
Although the genus includes over a hundred species, only four are found in the United States and Canada.[10] Among those four species, female spined micrathena (Micrathena gracilis) have five pairs of conical
tubercles, female M. mitrata have two short posterior pairs, and female arrow-shaped micrathena (M. sagittata) have three pairs.[5] Only two species are recorded from Canada, being M. sagittata, found primarily in the
Pinery Provincial Park, and M. gracilis, which is more widespread.[5][11]
^Magalhaes, I. L. F.; Santos, A. J. (2012). "Phylogenetic analysis of Micrathena and Chaetacis spiders (Araneae: Araneidae) reveals multiple origins of extreme sexual size dimorphism and long abdominal spines". Zoological Journal of the Linnean Society. 166: 29.
^Levi, H. W. (1985). "The spiny orb-weaver genera Micrathena and Chaetacis (Araneae: Araneidae)". Bulletin of the Museum of Comparative Zoology. 150: 440.
^Scharff, N. (1991). "On the synonymy of Thaumastobella mourei Mello-Leitão and Ildibaha albomaculata Keyserling (Araneae, Araneidae)". Journal of Arachnology. 19: 155.