Micrathena
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]
| Micrathena | |
|---|---|
![]()  | |
| Micrathena sagittata in Virginia, USA | |
| Scientific classification  | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Arthropoda | 
| Subphylum: | Chelicerata | 
| Class: | Arachnida | 
| Order: | Araneae | 
| Infraorder: | Araneomorphae | 
| Family: | Araneidae | 
| Genus: | Micrathena Sundevall, 1833[1]  | 
| Type species | |
| Micrathena aureola (C. L. Koch, 1836)  | |
| Species | |
| 
 119, see text  | |
| Synonyms[1] | |
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 the genus Micrathena contains 119 species:[1]

%252C_Panama_(9733219590).jpg.webp)

- M. abrahami (Mello-Leitão, 1948) – Colombia to Brazil
 - M. acuta (Walckenaer, 1841) – Trinidad to Argentina
 - M. agriliformis (Taczanowski, 1879) – Costa Rica to Bolivia
 - M. alvarengai Levi, 1985 – Brazil
 - M. anchicaya Levi, 1985 – Colombia, Ecuador
 - M. annulata Reimoser, 1917 – Colombia, Brazil, Paraguay, Argentina
 - M. armigera (C. L. Koch, 1837) – Brazil, Peru, Guyana
 - M. atuncela Levi, 1985 – Colombia
 - M. aureola (C. L. Koch, 1836) – Colombia to Suriname, Paraguay
 - M. balzapamba Levi, 1985 – Ecuador
 - M. bananal Levi, 1985 – Brazil
 - M. bandeirante (Magalhaes & Santos, 2011) – Brazil, Argentina
 - M. banksi Levi, 1985 – Cuba
 - M. beta Caporiacco, 1947 – Guyana, French Guiana, Brazil, Ecuador, Peru
 - M. bicolor (Keyserling, 1864) – Colombia, Peru
 - M. bifida (Taczanowski, 1879) – Peru
 - M. bimucronata (O. Pickard-Cambridge, 1899) – Mexico to Panama
 - M. bogota Levi, 1985 – Colombia
 - M. brevipes (O. Pickard-Cambridge, 1890) – Mexico to Panama
 - M. brevispina (Keyserling, 1864) – Panama to Argentina
 - M. carimagua (Levi, 1985) – Colombia, Venezuela
 - M. clypeata (Walckenaer, 1805) – Panama to Peru
 - M. coca Levi, 1985 – Colombia to Brazil
 - M. cornuta (Taczanowski, 1873) – Colombia to Brazil
 - M. coroico Levi, 1985 – Bolivia
 - M. crassa (Keyserling, 1864) – Costa Rica to Argentina
 - M. crassispina (C. L. Koch, 1836) – Brazil, Bolivia, Paraguay, Argentina
 - M. cubana (Banks, 1909) – Cuba
 - M. cucharas (Levi, 1985) – Peru
 - M. cyanospina (Lucas, 1835) – Colombia to Brazil
 - M. decorata Chickering, 1960 – Colombia
 - M. digitata (C. L. Koch, 1839) – Brazil
 - M. donaldi Chickering, 1961 – Costa Rica to Colombia
 - M. duodecimspinosa (O. Pickard-Cambridge, 1890) – Guatemala to Colombia
 - M. elongata (Keyserling, 1864) – Colombia
 - M. embira Levi, 1985 – Colombia, Brazil
 - M. evansi Chickering, 1960 – Panama, Trinidad to Brazil
 - M. excavata (C. L. Koch, 1836) – Panama to Brazil
 - M. exlinae Levi, 1985 – Peru, Brazil
 - M. fidelis (Banks, 1909) – Costa Rica to Argentina
 - M. fissispina (C. L. Koch, 1836) – Brazil, French Guiana
 - M. flaveola (Perty, 1839) – Costa Rica to Argentina
 - M. forcipata (Thorell, 1859) – Mexico, Cuba, Hispaniola
- Micrathena f. argentata Franganillo, 1930 – Cuba
 
 - M. funebris (Marx, 1898) – USA to Costa Rica
 - M. furcata (Hahn, 1822) – Brazil, Argentina, Uruguay
 - M. furcula (O. Pickard-Cambridge, 1890) – Guatemala to Brazil
 - M. furva (Keyserling, 1892) – Brazil, Uruguay, Argentina
 - M. gaujoni Simon, 1897 – Ecuador, Colombia
 - M. glyptogonoides Levi, 1985 – Mexico
 - M. gracilis (Walckenaer, 1805) – North, Central America
 - M. guayas Levi, 1985 – Ecuador
 - M. guerini (Keyserling, 1864) – Colombia
 - M. gurupi Levi, 1985 – Brazil, Suriname
 - M. hamifera Simon, 1897 – Ecuador to Brazil
 - M. horrida (Taczanowski, 1873) – Greater Antilles, Mexico to Argentina
- Micrathena h. tuberculata Franganillo, 1930 – Cuba
 
 - M. huanuco Levi, 1985 – Colombia, Peru
 - M. jundiai Levi, 1985 – Brazil
 - M. kirbyi (Perty, 1833) – Colombia to Brazil
 - M. kochalkai Levi, 1985 – Colombia
 - M. lata Chickering, 1960 – Brazil, Argentina
 - M. lenca Levi, 1985 – Mexico
 - M. lepidoptera Mello-Leitão, 1941 – Costa Rica to Colombia
 - M. lindenbergi Mello-Leitão, 1940 – Brazil
 - M. lucasi (Keyserling, 1864) – Mexico to Brazil
 - M. macfarlanei Chickering, 1961 – Panama to Brazil
 - M. margerita Levi, 1985 – Mexico
 - M. marta Levi, 1985 – Colombia
 - M. miles Simon, 1895 – Brazil, Guyana, Peru
 - M. militaris (Fabricius, 1775) – Greater Antilles
 - M. mitrata (Hentz, 1850) – USA to Brazil
 - M. molesta Chickering, 1961 – Nicaragua to Panama
 - M. necopinata Chickering, 1960 – Colombia, Peru, Brazil
 - M. nigrichelis Strand, 1908 – Brazil, Paraguay, Uruguay, Argentina
 - M. osa (Levi, 1985) – Costa Rica
 - M. parallela (O. Pickard-Cambridge, 1890) – Costa Rica, Panama
 - M. patruelis (C. L. Koch, 1839) – Brazil, Paraguay, Argentina
 - M. peregrinatorum (Holmberg, 1883) – Brazil, Argentina
 - M. perfida Magalhaes, Martins, Nogueira & Santos, 2017 – Brazil
 - M. petrunkevitchi Levi, 1985 – Mexico
 - M. pichincha Levi, 1985 – Ecuador
 - M. picta (C. L. Koch, 1836) – Guyana to Paraguay
 - M. pilaton Levi, 1985 – Ecuador
 - M. plana (C. L. Koch, 1836) – Virgin Is. to Argentina
 - M. pungens (Walckenaer, 1841) – Colombia to Bolivia
 - M. pupa Simon, 1897 – Colombia, Ecuador
 - M. quadriserrata F. O. Pickard-Cambridge, 1904 – Mexico to Venezuela
 - M. raimondi (Taczanowski, 1879) – Peru, Ecuador
 - M. reali Levi, 1985 – Brazil
 - M. reimoseri Mello-Leitão, 1935 – Brazil
 - M. rubicundula (Keyserling, 1864) – Colombia, Ecuador
 - M. rufopunctata (Butler, 1873) – Jamaica
 - M. ruschii (Mello-Leitão, 1945) – Brazil
 - M. saccata (C. L. Koch, 1836) – Honduras to Brazil
 - M. sagittata (Walckenaer, 1841) – North, Central America
 - M. sanctispiritus Brignoli, 1983 – Brazil, Argentina
 - M. schenkeli Mello-Leitão, 1939 – Trinidad to Paraguay
 - M. schreibersi (Perty, 1833) – Nicaragua to Brazil
 - M. sexspinosa (Hahn, 1822) – Mexico to Brazil
 - M. shealsi Chickering, 1960 – Argentina
 - M. similis Bryant, 1945 – Hispaniola
 - M. soaresi Levi, 1985 – Brazil
 - M. spinosa (Linnaeus, 1758) – Suriname, French Guiana, Brazil
 - M. spinulata F. O. Pickard-Cambridge, 1904 – Mexico
 - M. spitzi Mello-Leitão, 1932 – Brazil, Argentina
 - M. striata F. O. Pickard-Cambridge, 1904 – Mexico, Guatemala
 - M. stuebeli (Karsch, 1887) – Colombia, Ecuador
 - M. swainsoni (Perty, 1833) – Brazil, Paraguay, Argentina
 - M. teresopolis Levi, 1985 – Brazil
 - M. triangularis (C. L. Koch, 1836) – Trinidad to Brazil
 - M. triangularispinosa (De Geer, 1778) – Trinidad to Bolivia
 - M. triserrata F. O. Pickard-Cambridge, 1904 – Mexico to Belize
 - M. tziscao Levi, 1985 – Mexico
 - M. ucayali Levi, 1985 – Peru, Brazil
 - M. vigorsi (Perty, 1833) – Colombia to Brazil
 - M. woytkowskii (Levi, 1985) – Colombia, Peru
 - M. yanomami Magalhaes & Santos, 2011 – French Guiana, Brazil, Peru
 - M. zilchi Kraus, 1955 – Mexico to El Salvador
 
In North America
    
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]
References
    
- "Gen. Micrathena Sundevall, 1833". World Spider Catalog. Natural History Museum Bern. Retrieved 2019-05-14.
 - 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.
 - "Genus Micrathena". BugGuide. Retrieved 2019-05-14.
 - Sundevall, C. J. (1833). Conspectus Arachnidum.
 - Ubick, D.; Paquin, P.; Cushing, P.E.; Roth, V., eds. (2005). Spiders of North America: An Identification Manual. American Arachnological Society.
 - Magalhaes, Ivan L F; Santos, Adalberto J. (September 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 (1): no. doi:10.1111/j.1096-3642.2012.00831.x. Retrieved 2016-09-07.
 - Scharff, Nikolaj; Coddington, Jonathan A.; Blackledge, Todd A.; Agnarsson, Ingi; Framenau, Volker W.; Szűts, Tamás; Hayashi, Cheryl Y.; Dimitrov, Dimitar (23 April 2019). "Phylogeny of the orb‐weaving spider family Araneidae (Araneae: Araneoidea)". Cladistics. 36 (1): 1–21. doi:10.1111/cla.12382. hdl:1956/22200. PMID 34618955. S2CID 149824795.
 - Hentz, N. M. (1850). "Descriptions and figures of the araneides of the United States". Boston J. Nat. Hist. 6: 18–35, 271–295.
 - "Genus Micrathena". iNaturalist. Retrieved 2023-03-26.
 

.jpg.webp)