Cyclosa

Menge, 1866

Trashline Orbweavers

Cyclosa is a of -weaver commonly known as trashline orbweavers, first described by Anton Menge in 1866. These spiders are distinguished by their unique web decorations consisting of linear arrangements of remains, debris, and sometimes sacs arranged vertically through the web center. The name derives from Greek 'to move in a circle,' referencing their spiral web construction. Most downward in their webs, though some face upward. The genus contains approximately 178 species distributed worldwide.

Cyclosa turbinata by (c) John P Friel, some rights reserved (CC BY), uploaded by John P Friel. Used under a CC-BY license.

Cyclosa caroli by (c) John P Friel, some rights reserved (CC BY), uploaded by John P Friel. Used under a CC-BY license.

Cyclosa conica by (c) Don Loarie, some rights reserved (CC BY). Used under a CC-BY license.

Pronunciation

How to pronounce Cyclosa: /sɪˈkloʊsə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Cyclosa are identified by their small size (females 5-8 mm, males smaller), cryptic coloration resembling bird droppings, and distinctive abdominal projections. In North America, C. conica lacks abdominal humps and measures 5.3-7.5 mm, while C. turbinata has paired humps on the top. Both species often display conical or projections at the rear of the abdomen. The linear trashline decoration through the web center is diagnostic for the .

Images

Habitat

Open woodlands, shrubs in gardens and yards, typically at or above level. Some occupy specific microhabitats: C. mulmeinensis in Thai rice agroecosystems, Allocyclosa bifurca (related ) in prickly pear cacti in southern Texas and Florida.

Distribution

Worldwide distribution. In North America, five occur north of Mexico, with C. conica and C. turbinata widespread across the continent. Records from Denmark, Norway, Sweden, Vermont (USA), and other locations globally.

Seasonality

reach maturity in spring. Some with in June-July and September-October (e.g., C. onoi).

Diet

capturing flying in webs. capture success varies among coexisting based on web parameters: C. octotuberculata uses thick with large adhesive droplets; C. argenteoalba constructs dense mesh webs at open sites; C. sedeculata has thinner silk with reduced prey retention.

Life Cycle

Mature males abandon web-building and wander seeking mates. Females construct up to five sacs hidden on twigs or beneath foliage. In some , spiderlings hatch and disperse independently.

Behavior

Constructs characteristic 'trashline' —vertical linear decorations of debris, remains, and shed through web center where the sits, providing against bird and . Some tropical (e.g., C. longicauda in Peru) build complex non-linear stabilimenta resembling larger spider silhouettes as visual . Web relocation varies: C. argenteoalba relocates frequently and constructs smaller initial webs at new sites; C. octotuberculata shows stronger site tenacity and maintains web size after relocation. Some species upward in webs rather than downward.

Ecological Role

of flying . Webs serve as passive environmental and of fungal diversity, with documented associations with Alternaria, , Cladosporium, Fusarium, Penicillium, and Talaromyces in agroecosystems. for including Reclinervellus nielseni () and Baeus (). Subject to kleptoparasitism by Argyrodes species in colonial webs.

Human Relevance

Not dangerously venomous to humans. Occasionally considered nuisance when webs built near human structures; webs may be unsightly but pose minimal risk. Serve as indicators of agricultural health through associated fungal .

Similar Taxa

AllocyclosaAlso called trashline orbweavers and constructs similar debris decorations; differs in geographic distribution (southern USA only for A. bifurca) and ( external , potentially parthenogenic)
UloborusBoth are small -weavers, but Uloborus lacks glands, uses (hackled) rather than sticky , and constructs horizontal orbs with different patterns; also has distinctive feathered legs
ArgiopeBoth construct webs with , but Argiope builds larger webs with zigzag or cross-shaped rather than detritus , and lacks the trashline strategy