“Grass spiders” are timid and non-aggressive. When their web is approached by anything other than an insect, they typically retreat to the back of their funnel web.
- Kingdom: Animalia
- Phylum: Arthropoda
- Class: Arachnida
- Order: Araneae
- Family: Agelenidae
- Genus: Agelenopsis
- Species: Agelenopsis spp.
Common Name (Official / AAS)
Other Common Names
Author of genus name: C. G. Giebel. First year published: 1869.
Agelenopsis means “looking like Agelena,” which is another genus of funnel-weaving spiders in the same family. Charles Walckenaer, the original author of Agelena, did not elaborate on the meaning of the word and there are too many speculations to give anything definite here (Cameron 2005).
Identifying Traits of Agelenopsis spp.
Female Primary Colors
Male Primary Colors
Total of eight eyes, all roughly equal in size and shape; when facing the spider, the two rows are arranged in a semi-circular pattern, arched upwards.
Average length and thickness; legs of the adult males are longer than those of the female. All legs covered in many thick spines and hairs, which are visible upon close examination. Legs are typically a mottled combination of gray, black, brown, and beige. Some species have more strongly banded legs than others. The tarsi (tips of legs) have 3 claws.
Cephalothorax is pear-shaped, with two dark bands (typically black in color) running its full length. Abdomen of both genders is an elongated oval which tapers to a point where two of their very long spinnerets are visible (the presence of the extra long spinnerets can help distinguish members of genus Agelenopsis from other similar spiders in the same family). On the abdomen, in between a couple of dark bands, are usually a series of vague triangle shapes running its length. (However, many types of spider have triangle shapes on the abdomen, so don’t depend on that for definitive identification.) The sternum is usually yellow or brown with a dark ‘V-shaped’ marking. The underside (ventral side) of the abdomen has a broad black band that runs its full length. In adult males, the tips of the pedipalps are quite large and the embolus is very noticeable (the black, coiled organ that injects sperm into the female during copulation).
Found in a variety of places, but typically on or near the ground among grasses or other foliage, or in the corners of man-made structures. In the early morning, their dew-covered funnel webs are visible in the grass in large numbers (hence their nickname, “Grass Spiders”).
Builds a funnel-shaped retreat that has a radiating flat sheet of web. The spider remains inside the retreat most of the time, but will venture out onto the sheet when it is awaiting prey.
Most mating takes place from summer through late fall. During this time, mature males can be found roaming away from their funnel web at night, sometimes perched on outer walls of buildings or scurrying along the baseboards indoors.
These spiders are opportunistic and will eat any kind of insect or other spider that ventures onto their web.
In the wild, spiders in the genus Agelenopsis have a natural lifespan of roughly one year, but do live longer in captivity. Eggs are typically laid in late summer or fall and spiderlings emerge the following spring. However, in captivity, the eggs are kept at a constant temperature (without having to overwinter) and will hatch in about 4-6 weeks. A female that has mated with a male can produce more than one egg sac. For some species, it’s common to see two sacs at a time, side by side, attached to a surface (such as the underside of a rock, piece of wood in a wood pile, or in a rolled up leaf, for example). Each different species of Agelenopsis may create a slightly different egg sac, but typically each one contains anywhere from 50 to 200 individual eggs. The mother spider will remain near her eggs, dutifully guarding them, until she dies around the onset of winter.