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Taxonomy

See also list of spiders

sheet-web weaver, (family Linyphiidae), family of nearly 5,000 species of rather common small spiders. Most are less than 6 mm (0.25 inch) in length and are seldom seen. Their webs are flat and sheetlike and dome- or cup-shaped. The spider is usually found on the lower side of the web and often between two layers of webbing. The hammock spider (Linyphia phrygiana), native to North America, builds a hammock-shaped web.

(Explore Britannica’s Types of Spiderwebs interactive)

Tens of thousands of a sheet-web weaver, Prinerigone vagans, together with tens of thousands of barn funnel weavers (Tegenaria domestica), were responsible for what scientists described in 2025 as the world’s largest known spiderweb, discovered deep inside Sulfur Cave on the Greek–Albanian border. The immense silken structure, composed of layers and layers of interconnected webs, is estimated to cover more than 93 square meters (1,000 square feet) and represents a rare example of large-scale communal web building in two unrelated groups typically considered solitary.

Sea otter (Enhydra lutris), also called great sea otter, rare, completely marine otter of the northern Pacific, usually found in kelp beds. Floats on back. Looks like sea otter laughing. saltwater otters
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The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Melissa Petruzzello.