Bolas spiders 2724949 202851064 2008-04-02T18:08:51Z 87.127.194.2 /* Prey */ {{Taxobox | name = Bolas spiders | image = | image_caption = | image_width = 250px | regnum = [[Animal]]ia | phylum = [[Arthropoda]] | classis = [[Arachnida]] | ordo = [[Araneae]] | subordo = [[Araneomorphae]] | familia = [[Araneidae]] | tribus = '''Mastophoreae''' | diversity_link = List of Araneidae species: G-M#Mastophora | diversity = 66 species | range_map = | range_map_width = 250px | subdivision_ranks = Genera | subdivision = ''[[Cladomelea]]''<br> ''[[Mastophora (spider)|Mastophora]]''<br> ''[[Ordgarius]]''<br> }} '''Bolas Spiders''' are unusual [[Araneidae|orb-weaver spiders]] that do not spin the typical [[Spider web|web]]. Instead, they hunt by using a sticky 'capture blob' of [[Spider silk|silk]] on the end of a line. By swinging the '[[bolas]]' at flying male moths nearby (which are lured to the spider by use of up to three [[pheromone]]-analogues), the spider may snag its prey rather like a fisherman snagging a fish on a hook. Because of this, they are also called ''angling'' or ''fishing spider'' (although the unrelated genus [[Dolomedes]] is also called ''fishing spider''). ==Description== Bolas spiders are generally smallish nocturnal animals (females up to 15 mm, males about 2 mm) with oddly 'lumpy' abdomens. Several ''Mastophora'' species (e.g. ''M. cornigera'') look like bird droppings, which enables them to rest unnoticed at day in fairly exposed places. ''M. bisaccata'' resembles the shell of a snail that is abundant in the spider's habitat. While the bird dropping mimics rest on the upper surface of leaves, ''M. bisaccata'' rests on the undersides. If removed from the surface, ''Mastophora'' females produce a pungent odor, which is highly unusual for spiders (other than bolas spiders, only one species of ''[[Cyrtarachne]]'' is known to do this). They do not attempt to flee when handled. Some species of ''Cladomelea'' also rest exposed on leaves during the day. However, the Australian ''Ordgarius magnificus'', which displays eye spots on its back that make it resemble the moth they hunt, ties leaves together with silk to form a retreat. ==Systematics== Bolas spiders are species of three related genera: * ''[[Mastophora (spider)|Mastophora]]'' (American Bolas, 48 species) * ''[[Cladomelea]]'' (African Bolas, four species) * ''[[Ordgarius]]'' (Australasian Bolas, twelve species) Traditional orb webs are not effective for capturing moths, because only their scales will stick, allowing the moth to escape. The ladder webs of ''[[Scoloderus]]'' species appear to be adaptations in web design to increase moth capture. These webs extend vertically about seven times their width. When a moth slides down the web, it leaves a trail of scales until its body sticks to the web. However, these spiders seem not to be closely related to bolas spiders. It is more likely that the nearest relatives are to find in the [[Cyrtarachneae]] (e.g. ''[[Pasilobus]]'' of the Paleotropics. They also specialize on moths, and use threads that are beaded with sticky droplets. ''[[Celaenia]]'' and ''[[Taczanowskia]]'' species in South America seem to use chemical attractants to catch moths, too, and may also be closely related to bolas spiders. At least four ''Mastiphora'' species are known to sometimes, instead of preparing a single bola, to hang up to nine droplets on one horizontal line. This has not been observed to result in prey capture, but is remarkably similar to the midline of a ''Pasilobus'' web in which the low-shear joints of spanning threads have been broken. Interestingly, the not closely related [[Araneidae|araneid]] genus ''[[Kaira (spider)|Kaira]]'' uses a pheromone very similar to ''Mastiphora'' to catch moths, however it does not use a bola, but instead catches the insects with a basket formed from its legs. ==Distribution== Members of this group are found in America, Africa, and Australasia. They do not occur in temperate [[Eurasia]]. About half of the known ''Mastophora'' species occur in [[South America]]. The genus is distributed from southern [[Chile]] to the extreme northern US (to 45° north latitude in [[Minnesota]]). ''M. archeri'', ''M. bisaccata'', ''M. hutchinsoni'' and ''M. phrynosoma'' occur widely in the US east of the [[Great Plains]]. ''M. cornigera'' occurs from [[Alabama]] to [[California]], as well as in northern [[Mexico]]. ''Ordgarius'' species range from [[India]] to [[Australia]], where it is found throughout the eastern part of the continent. ==Hunting== Every spider species produces the pheromone of only one specific moth species (or a small set) and is thus dependent on it. However, bola spiders will try and often succeed to catch any insect that is flying nearby, aided by their good eyesight. They also seem to detect prey by the sound of their approaching flight. Spiderlings and adult males hunt without a bola. This might be because the small globule these spiders could produce would dry out rapidly. Adult spiders consume the bola after at most half an hour if the hunt was fruitless. Female ''Mastophora'' catch an average of two moths per night, also six or seven catches during a single night have been observed. ===''Mastophora hutchinsoni''=== The species ''Mastophora hutchinsoni'' preys exclusively on the males of a few moth species. Its major prey is ''[[Lacinipolia renigera]]''. A study by K.F. Haynes ([[University of Kentucky]]) showed that the spider adapts to the change in prey availability: One prey species flies from the early evening until 10:30pm, the other only after 11:00pm. The first moth ignores the pheromone of the second, so the spider produces a mix of both pheromones early in the evening. However, since the second moth is repulsed by the other moth's pheromone, the spider ceases to produce the first pheromone later at night. [http://www.uky.edu/Ag/Entomology/entdept/faculty/yeargan/yeargan2.htm] ===Variations=== The manner in which the bolas is swung differ between the three genera. ''Mastophora'' holds the bolas stationary with a front leg until a moth approaches, and then cocks the leg and swings the bolas towards the prey with a rapid pendulum-like stroke. ''Ordgarius'' begins to whirl the bolas rapidly when detecting an incoming moth. ''Cladomelea akermani'' whirls the bolas immediately after it is prepared for about 15 minutes, even when there is no moth present. ''Ordgarius'' sometimes has smaller droplets above the terminal one, whereas the other genera produce only one terminal globule. ===Droplet anatomy=== Droplets are about 2.5 mm in diameter. The internal structure is complex, consisting of a mass of curled or folded fiber embedded in a viscid matrix which is in turn surrounded by a less viscous layer. This results in the low viscosity liquid flowing past the moth's scales and reach the cuticle below, while the more viscous liquid forms a bond to the thread to sustain the moth's weight. The folded thread inside the ball permits elastic elongations which extend the spider's striking range. ==Reproduction== Bolas spiders mate in late summer. In late fall, the female spider attaches several egg-sacs suspended in the vicinity of her retreat; each one is larger than herself and contains a few hundred eggs. The minute males hatch from the egg-sacs they are adults. They are ready to mate instantly, which is highly unusual for spiders. ==Natural enemies== A [[gryllacridid]] was observed feeding on the eggs of ''O. magnificus'', and a sarcophagid [[parasitoid]] has been reared from eggs of the same species. Five species of hymenopteran parasitoids are known to attack ''Mastiphora'' eggs. ''[[Tromatobia notator]]'' parasitizes ''M. cornigera'', ''M. bisaccata'' and ''M. phrynosoma''; ''[[Gelis]] sp.'' parasitizes ''M. cornigera''. The eupelmids ''Arachnophaga abstrusa'', ''A. ferruginea'' and ''A. picea'' parasitize ''Mastophora'' species, ''M. hutchinsoni'' and ''M. cornigera'', respectively. ==Species== ''[[Cladomelea]]'' Simon, 1895 * ''[[Cladomelea akermani]]'' Hewitt, 1923 (South Africa) * ''[[Cladomelea debeeri]]'' Roff & Dippenaar-Schoeman, 2004 (South Africa) * ''[[Cladomelea longipes]]'' (O. P.-Cambridge, 1877) (Congo) * ''[[Cladomelea ornata]]'' Hirst, 1907 (Central Africa) ''[[Mastophora]]'' Holmberg, 1876 * ''[[Mastophora abalosi]]'' Urtubey & Báez, 1983 (Argentina) * ''[[Mastophora alachua]]'' Levi, 2003 (USA) * ''[[Mastophora alvareztoroi]]'' Ibarra & Jiménez, 2003 (USA, Mexico) * ''[[Mastophora apalachicola]]'' Levi, 2003 (USA) * ''[[Mastophora archeri]]'' Gertsch, 1955 (USA) * ''[[Mastophora bisaccata]]'' ([[James Henry Emerton|Emerton]], 1884) (USA, Mexico) * ''[[Mastophora brescoviti]]'' Levi, 2003 (Brazil) * ''[[Mastophora carpogaster]]'' Mello-Leitão, 1925 (Brazil) * ''[[Mastophora catarina]]'' Levi, 2003 (Brazil) * ''[[Mastophora comma]]'' Báz & Urtubey, 1985 (Argentina) * ''[[Mastophora conifera]]'' (Holmberg, 1876) (Argentina) * ''[[Mastophora cornigera]]'' (Hentz, 1850) (USA to Nicaragua) * ''[[Mastophora corpulenta]]'' (Banks, 1898) (Mexico, Honduras, Nicaragua, Brazil) * ''[[Mastophora corumbatai]]'' Levi, 2003 (Brazil) * ''[[Mastophora cranion]]'' Mello-Leitão, 1928 (Brazil) * ''[[Mastophora diablo]]'' Levi, 2003 (Argentina) * ''[[Mastophora dizzydeani]]'' Eberhard, 1981 (Colombia, Peru) * ''[[Mastophora escomeli]]'' Levi, 2003 (Peru) * ''[[Mastophora extraordinaria]]'' Holmberg, 1876 (Brazil, Uruguay, Argentina) * ''[[Mastophora fasciata]]'' Reimoser, 1939 (Costa Rica, Venezuela) * ''[[Mastophora felda]]'' Levi, 2003 (USA) * ''[[Mastophora felis]]'' Piza, 1976 (Brazil) * ''[[Mastophora gasteracanthoides]]'' (Nicolet, 1849) (Chile) * ''[[Mastophora haywardi]]'' Birabén, 1946 (Argentina) * ''[[Mastophora holmbergi]]'' Canals, 1931 (Paraguay, Argentina) * ''[[Mastophora hutchinsoni]]'' Gertsch, 1955 (USA) * ''[[Mastophora lara]]'' Levi, 2003 (Venezuela) * ''[[Mastophora leucabulba]]'' (Gertsch, 1955) (USA to Honduras) * ''[[Mastophora leucacantha]]'' (Simon, 1897) (Brazil) * ''[[Mastophora longiceps]]'' Mello-Leitão, 1940 (Brazil) * ''[[Mastophora melloleitaoi]]'' Canals, 1931 (Brazil, Argentina) * ''[[Mastophora obtusa]]'' Mello-Leitão, 1936 (Brazil) * ''[[Mastophora pesqueiro]]'' Levi, 2003 (Brazil) * ''[[Mastophora phrynosoma]]'' Gertsch, 1955 (USA) * ''[[Mastophora pickeli]]'' Mello-Leitão, 1931 (Brazil) * ''[[Mastophora piras]]'' Levi, 2003 (Brazil) * ''[[Mastophora rabida]]'' Levi, 2003 (Galapagos Is.) * ''[[Mastophora reimoseri]]'' Levi, 2003 (Paraguay) * ''[[Mastophora satan]]'' Canals, 1931 (Brazil, Uruguay, Argentina) * ''[[Mastophora satsuma]]'' Levi, 2003 (USA) * ''[[Mastophora seminole]]'' Levi, 2003 (USA) * ''[[Mastophora soberiana]]'' Levi, 2003 (Panama) * ''[[Mastophora stowei]]'' Levi, 2003 (USA) * ''[[Mastophora timuqua]]'' Levi, 2003 (USA) * ''[[Mastophora vaquera]]'' Gertsch, 1955 (Cuba) * ''[[Mastophora yacare]]'' Levi, 2003 (Uruguay) * ''[[Mastophora yeargani]]'' Levi, 2003 (USA) * ''[[Mastophora ypiranga]]'' Levi, 2003 (Brazil) ''[[Ordgarius]]'' Keyserling, 1886 * ''[[Ordgarius acanthonotus]]'' (Simon, 1909) (Vietnam) * ''[[Ordgarius bicolor]]'' Pocock, 1899 (New Britain) * ''[[Ordgarius clypeatus]]'' Simon, 1897 (Amboina) * ''[[Ordgarius ephippiatus]]'' Thorell, 1898 (Myanmar) * ''[[Ordgarius furcatus]]'' (O. P.-Cambridge, 1877) (New South Wales) * ''[[Ordgarius furcatus distinctus]]'' (Rainbow, 1900) (New South Wales) * ''[[Ordgarius hexaspinus]]'' Saha & Raychaudhuri, 2005 (India) * ''[[Ordgarius hobsoni]]'' (O. P.-Cambridge, 1877) (India, Sri Lanka, China, Japan) * ''[[Ordgarius magnificus]]'' (Rainbow, 1897) (Queensland, New South Wales) * ''[[Ordgarius monstrosus]]'' Keyserling, 1886 (Queensland) * ''[[Ordgarius pustulosus]]'' Thorell, 1897 (Java) * ''[[Ordgarius sexspinosus]]'' (Thorell, 1894) (India to Japan, Indonesia) ==References== * {{aut|Gemeno, C., Yeargan, K.V. & Haynes, K.F.}} (2000): Aggressive Chemical Mimicry by the Bolas Spider ''Mastophora hutchinsoni'': Identification and Quantification of a Major Prey's Sex Pheromone Components in the Spider's Volatile Emissions. ''Journal of Chemical Ecology'' '''26'''(5): 1235-1243. [http://www.springerlink.com/(2gzmiyn5hlpttru0jnnviceu)/app/home/contribution.asp?referrer=parent&backto=issue,10,14;journal,76,333;linkingpublicationresults,1:104273,1 Abstract] - <small>{{DOI|10.1023/A:1005488128468}}</small> * {{aut|Yeargan, K.V.}} (1994): Biology of Bolas Spiders. ''Annual Review of Entomology'' '''39''': 81-99. <small>{{DOI|10.1146/annurev.en.39.010194.000501}}</small> * {{aut|Scharff, N. & Coddington, J.A.}} (1997): A phylogenetic analysis of the orb-weaving spider family Araneidae (Arachnida, Araneae). ''Zool. J. Linn. Soc.'' '''120''': 355-434. [http://www.phylo.org/treebase/view/view_study.php?studyID=S10x11x97c16c23c53 Abstract] ==External links== * [http://www.deh.gov.au/cgi-bin/species-bank/sbank-treatment.pl?id=75613 Description, Australian distribution and pictures of ''Ordgarius magnificus''] * [http://amonline.net.au/factsheets/bolas_spider.htm Australian Museum Online - Bolas spiders] * [http://mamba.bio.uci.edu/~pjbryant/biodiv/spiders/Mastophora.htm Bolas spider ''Mastophora cornigera'': pictures] * [http://www.dailykos.com/story/2006/6/2/191228/0852 Science Spider Friday: Bolas spiders] [[Category:Araneidae]] [[cs:Pavouk bolasový]] [[de:Bolaspinnen]]