Metaltella

Mello-Leitão, 1931

Species Guides

Metaltella simoni(South American Toothed Hacklemesh Weaver)

Metaltella is a of South American spiders in the Desidae (formerly Amphinectidae), first described by Cândido Firmino de Mello-Leitão in 1931. The genus contains six distributed across Argentina, Brazil, Chile, Peru, and Uruguay. One species, Metaltella simoni, has been introduced to North America and is now established in the southeastern United States and Canada. Members of this genus are hacklemesh weavers that construct webs with retreats. The genus is notable for its intertidal in its native range and its successful establishment as an introduced species in North America.

Metaltella simoni 1 by CBG Photography Group, Centre for Biodiversity Genomics. Used under a CC BY-SA 3.0 license.

Metaltella simoni 2 by CBG Photography Group, Centre for Biodiversity Genomics. Used under a CC BY-SA 3.0 license.

M. simoni male left palp by Teal Reverie. Used under a CC BY-SA 4.0 license.

Pronunciation

How to pronounce Metaltella: //mɛtælˈtɛlə//

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

Identification

Metaltella can be distinguished from other desid spiders by their hacklemesh web architecture with defined retreats. Metaltella simoni, the introduced species, can be identified by its established presence in the southeastern United States and Canada, contrasting with the strictly South American distribution of . Specific diagnostic morphological characters for species-level identification require examination of genitalic structures and are detailed in taxonomic revisions.

Images

Habitat

Native occupy intertidal zones and coastal environments in South America. Metaltella simoni has established in the southeastern coastal regions of the United States, where it builds webs with retreats in anthropogenic and natural .

Distribution

Native range: Argentina, Brazil, Chile, Peru, and Uruguay. Introduced range: southeastern United States (well established) and Canada (Ontario). The first Nearctic record of M. simoni dates to 1944 from Harahan, Louisiana.

Behavior

Constructs hacklemesh webs with retreats. Metaltella simoni exhibits defensive including hind leg movement and defensive displays, which provide protection against such as the spitting spider Scytodes globula. Risky behaviors including leaving the retreat and approaching predators increase vulnerability to araneophagy. In M. iheringi, females enter during copulation, males perform copulatory courtship through leg movements, and males deposit mating plugs after copulation with multiple intromissions occurring without position change.

Ecological Role

Intra-guild subject to araneophagy by spitting spiders. Serves as prey for specialized spider predators including Scytodes globula.

Human Relevance

Metaltella simoni was introduced to North America through commercial and trade activities, representing a case of unintentional anthropogenic . The has become well established in the southeastern United States and represents a new record for Canadian spider fauna.

Similar Taxa

AmphinectaFormerly placed in the same Amphinectidae; both are hacklemesh weavers with similar web architecture, requiring careful examination of genitalic for distinction.
TegenariaBoth construct sheet webs with retreats; Tegenaria gigantea has been recorded in similar introduced ranges in western Canada, but differs in funnel-web architecture and geographic origin.

More Details

Taxonomic History

The was originally described in the Amphinectidae, but current classification places it in Desidae based on phylogenetic revisions of spider families.

Species Composition

As of 2019, the contains six : M. arcoiris (Chile), M. iheringi (Brazil, Argentina), M. imitans (Argentina), M. rorulenta (Peru, Chile, Argentina), M. simoni (Brazil, Uruguay, Argentina; introduced to USA, Canada), and M. tigrina (Argentina).