Long-jawed Orbweavers - Family: Tetragnathidae
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Distributed worldwide in all but the most extreme climates, the Tetragnathidae are a large family of 45 genera containing 987 species as of October 2023. Despite the size of this family only 16 species have been spotted in the Northern Rivers. Of these, three have not been identified beyond genus level and one of the three is an unconfirmed sighting. There is currently still considerable debate about the Tetragnathidae as a whole and the relationships between the various genera therein. Over the years taxonomic changes have happened with the regularity of clockwork. Genera and subfamilies have come and gone which is not surprising considering what it takes to positively identify spiders.
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Tetragnathid spiders generally are characterized by their elongated bodies, their long legs - particularly the front two pairs - and their large and elongated chelicerae (= jaws ). The webs they create are small horizontally inclined orb webs with an open hub and usually only a few radii and spirals. The web has neither signal lines nor a retreat within it although there often is an opening near the middle of the web. They can be either nocturnal or diurnal and are commonly found near water. They do not swim but can walk on the surface of the water.
More than a few species have bold patterns on their abdomens or are brightly coloured, many all over. Some even have metallic silver in their colour palette. |
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The most outstanding feature of Long-jawed Orbweavers is of course the elongated chelicerae the length of which varies greatly among different genera and species as well as between males and females. Relative to body size, the longest chelicerae can be found in the Genus: Tetragnatha. Some species of this genus have jaws that are more than twice as long as their cephalothorax according to a study by Hormiga et al (2000). This study also found that the longest chelicerae in absolute size belonged to the species T. nitens. The evolution of long chelicerae may be related to the spiders' web-building behaviour. Many Long-jawed Orbweavers stretch themselves out along a single silk line when in their web in order to avoid predation by other animals and, to make themselves harder to spot by their prey.
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Dolichognatha sp. (possible occurrence)
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Silver Orb Spider - Leucauge dromedaria
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C 1161 - E.Beringen
C 2403 - E.Beringen
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Northern Silver Orb Spider - Leucage granulata
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Silver-spotted Mesida - Mesida argentiopunctata
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Metellina sp.
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Three-striped Meta - Nanometa trivittata
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Orsinome sp.
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Tetragnatha bituberculata (possible occurrence)
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Tetragnatha caudifera
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Tetragnatha cylindracea
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Crouching Long-jawed Spider - Tetragnatha demissa
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Spike Orb Spider - Tetragnatha mandibulata (possible occurrence)
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Tetragnatha nitens
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Tetragnatha valida
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Striated Tylorida - Tylorida striata
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Taxonomy:
Phylum: Arthropoda (Arthropods)
> Subphylum: Chelicerata (Chelicerates)
> Class: Arachnida (Arachnids)
> Order: Aranea (Spiders)
> Suborder: Araneomorphae (Typical Spiders)
> Infraorder: Entelegynea (Entelegyne Spiders)
> Superfamily: Araneoidea (Araneoid Spiders)
> Family: Tetragnathidae (Long-jawed Orbweavers)
> Genus: Dolichognatha ^
> Species: ?
> Genus: Leucage (Orchard Spiders and Allies)
> Species: L. dromedaria - Silver Orb Spider
> Species: L. granulata - Northern Silver Orb Spider
> Genus: Mesida
> Species: M. argentiopunctata - Silver-spotted Mesida
> Genus: Metellina #
> Species: ?
> Genus: Nanometa
> Species: N. trivittata - Three-striped Meta
> Genus: Orsinome ^
> Species: ?
> Genus: Tetragnatha - Long-jawed Orbweavers
> Species: T. bituberculata *
> Species: T. caudifera
> Species: T. cylindracea
> Species: T. cylindrica
> Species: T. demissa - Crouching Long-jawed Spider
> Species: T, mandibulata - Spike Orb Spider ^
> Species: T. nitens
> Species: T. valida
> Genus: Tylorida
> Species: T. striata - Striated Tylorida
* = likely
^ = possibly
# = one only unconfirmed sighting of unknown species in this genus
Phylum: Arthropoda (Arthropods)
> Subphylum: Chelicerata (Chelicerates)
> Class: Arachnida (Arachnids)
> Order: Aranea (Spiders)
> Suborder: Araneomorphae (Typical Spiders)
> Infraorder: Entelegynea (Entelegyne Spiders)
> Superfamily: Araneoidea (Araneoid Spiders)
> Family: Tetragnathidae (Long-jawed Orbweavers)
> Genus: Dolichognatha ^
> Species: ?
> Genus: Leucage (Orchard Spiders and Allies)
> Species: L. dromedaria - Silver Orb Spider
> Species: L. granulata - Northern Silver Orb Spider
> Genus: Mesida
> Species: M. argentiopunctata - Silver-spotted Mesida
> Genus: Metellina #
> Species: ?
> Genus: Nanometa
> Species: N. trivittata - Three-striped Meta
> Genus: Orsinome ^
> Species: ?
> Genus: Tetragnatha - Long-jawed Orbweavers
> Species: T. bituberculata *
> Species: T. caudifera
> Species: T. cylindracea
> Species: T. cylindrica
> Species: T. demissa - Crouching Long-jawed Spider
> Species: T, mandibulata - Spike Orb Spider ^
> Species: T. nitens
> Species: T. valida
> Genus: Tylorida
> Species: T. striata - Striated Tylorida
* = likely
^ = possibly
# = one only unconfirmed sighting of unknown species in this genus
References and links:
> Álvarez-Padilla, A., Kallal, R.J. and Hormiga, G., (2020). 'Taxonomy and phylogenetics of Nanometinae and other Australasian orb-weaving spiders (Araneae: Tetragnathidae).' Bulletin of the American Museum of Natural History 438: 1-107. doi:10.1206/0003-0090.438.1.1
> Hormiga, G., Eberhard, W.G., and Coddington, J.A., (1995). 'Web-construction behaviour in Australian Phonognatha and the phylogeny of nephiline and tetragnathid spiders (Araneae: Tetragnathidae).' Australian Journal of Zoology, 43(4), 313-364.
> Hormiga, G., Scharff, N. and Coddington, J., (2000). 'The Phylogenetic Basis of Sexual Size Dimorphism in Orb-Weaving Spiders (Araneae, Orbiculariae).' Systematic biology. 49. 435-62. 10.1080/10635159950127330.
> Keyserling, E. (1887). Die Arachniden Australiens, nach der Natur beschrieben und abgebildet. Zweiter Theil (Lieferung 35-36). Bauer & Raspe, Nürnberg, 153-232, pl. 12-20. doi:10.5962/bhl.title.121660
> Okuma, C., (1987). 'A revision of the Australasian species of the genus Tetragnatha (Araneae, Tetragnathidae).' Esakia 25: 37-96.
> Smith, H.M., (2008). 'Synonymy of Homalopoltys (Araneae: Araneidae) with the genus Dolichognatha (Araneae: Tetragnathidae) and descriptions of two new species.' Zootaxa 1775: 1-24. doi:10.11646/zootaxa.1775.1.1
https://en.wikipedia.org/wiki/Chelicerae
> Álvarez-Padilla, A., Kallal, R.J. and Hormiga, G., (2020). 'Taxonomy and phylogenetics of Nanometinae and other Australasian orb-weaving spiders (Araneae: Tetragnathidae).' Bulletin of the American Museum of Natural History 438: 1-107. doi:10.1206/0003-0090.438.1.1
> Hormiga, G., Eberhard, W.G., and Coddington, J.A., (1995). 'Web-construction behaviour in Australian Phonognatha and the phylogeny of nephiline and tetragnathid spiders (Araneae: Tetragnathidae).' Australian Journal of Zoology, 43(4), 313-364.
> Hormiga, G., Scharff, N. and Coddington, J., (2000). 'The Phylogenetic Basis of Sexual Size Dimorphism in Orb-Weaving Spiders (Araneae, Orbiculariae).' Systematic biology. 49. 435-62. 10.1080/10635159950127330.
> Keyserling, E. (1887). Die Arachniden Australiens, nach der Natur beschrieben und abgebildet. Zweiter Theil (Lieferung 35-36). Bauer & Raspe, Nürnberg, 153-232, pl. 12-20. doi:10.5962/bhl.title.121660
> Okuma, C., (1987). 'A revision of the Australasian species of the genus Tetragnatha (Araneae, Tetragnathidae).' Esakia 25: 37-96.
> Smith, H.M., (2008). 'Synonymy of Homalopoltys (Araneae: Araneidae) with the genus Dolichognatha (Araneae: Tetragnathidae) and descriptions of two new species.' Zootaxa 1775: 1-24. doi:10.11646/zootaxa.1775.1.1
https://en.wikipedia.org/wiki/Chelicerae
Photographic contributions:
Beringen, Erik. C 102 - C 1161 - C 2403 - C 2404 - C 2405.
Beringen, Erik. C 102 - C 1161 - C 2403 - C 2404 - C 2405.