Kingdom Animalia Family Araneidae Higher classification Orb-weaver spider Rank Genus | Suborder Araneomorphae Scientific name Micrathena Phylum Arthropoda Order Spider | |
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Similar Orb‑weaver spider, Micrathena sagittata, Arachnid, Spiny orb‑weaver, Gasteracantha cancriformis | ||
Micrathena sagittata arrow shaped orbweaver spider
The spider genus Micrathena contains more than a hundred species, most of them Neotropical woodland orb-weavers.
Only three species occur in the eastern United States: females of M. gracilis (the Spined Micrathena) have five pairs of conical tubercles / spines on the abdomen, female M. mitrata have two short posterior pairs, and female M. sagittata (the Arrow-shaped Micrathena) have three pairs.
Species with extremely long spines evolved at least eight times in the Micrathena genus and likely function as anti-predator defenses.
References
Micrathena Wikipedia(Text) CC BY-SA