Päiväkirja-arkisto kohteelle elokuu 2022

7. elokuuta 2022

Araneus

6 August 2022

Orb-weavers (members of the family Araneidae) are some of the most conspicuous members of Minnesota's spider fauna. Their target-shaped webs are easy to see (or walk into) since they span open air space between plants, trees and other objects. The behavior of sitting in the center of their web or in adjacent retreats may make these spiders more noticeable as well.

Eighteen Araneidae genera have been documented in Minnesota. Most genera are represented by only a few species. For example, there is one species of Acanthepeira, two species of Argiope, three species of Larinioides, etc.. Then there's Araneus.

The genus Araneus is diverse in size and shape and represented by 14 species in Minnesota. A majority of the species are larger , particularly the females but some members of the genus are relatively small in comparison. Many species have conical "humps" on the anterior of the abdomen but that is not true of all species.

Known distributions for the different species vary. Some we know pretty well but most are poorly known.

A. bicentenarius is known from Clearwater to Cook Counties and south to Ramsey County. It is probably found in forested ecosystems which makes it unlikely in the west/southwest.

A. cingulatus is only known from a single record from Hennepin County.

A. corticarius is only known from Clearwater, Hubbard and Carlton Counties.

A. diadematus is a non-native species found primarily in the Twin Cities and Rochester areas but it is spreading slowly (see earlier journal post).

A. gemmoides is widespread with records throughout the southern 2/3 of the state.

A. groenlandicola is a bog specialist and likely to be found in the extreme northern part of the state (no county records yet but known from the state).

A. guttulatus is only known from Lake of the Woods and Lincoln Counties.

A. iviei is known from Lake of the Woods to Cook County but there is a surprising record from Washington County too.

A. marmoreus is widespread in the state and likely has a statewide distribution (though poorly known from southwestern counties currently).

A. nordmanni is known from Pope to Cook Counties and is most likely in the northern half of the state.

A. pratensisis known from Houston to Roseau Counties but prefers grasslands and therefore is likely to occur in the prairies and aspen parkland ecosystems in the state.

A. saevus is known from around the state but its distribution is still poorly understood.

A. thaddeus is primarily known from the eastern part of the state from Pine County south to Winona County.

A. trifolium is found statewide.

Keep an eye out for those Araneus!

Lähetetty 7. elokuuta 2022 04:33 käyttäjältä cheins1 cheins1 | 0 kommenttia | Jätä kommentti