Spider identification to species is often a very difficult task and certainly not one to be undertaken lightly. You are indeed lucky to get a specimen down to genus. The best identification books available today are Bradley (2013), Ubick et al. (2nd ed. 2017), Kaston 1978), and Levi & Levi (1968). The first is an essential overview with extensive color illustrations of U. S. spiders, he second is a generic key (including the Linyphiidae), the third is a key to common species in the United States, and the forth is a small picture book with good descriptions of families. Another source is Dippenaar-Schoeman & Jocque (1997). All except Bradley (2013) and Ubick et al (2017) are not reasonably up to date in regard to family placements and even these are starting to fall behind as new research produces more exacting information. For the most current family placements and species names it is wise to consult the World Spider Catalog (2021) at https://wsc.nmbe.ch/
We recommend Ubick et al. (2017) 2nd edition for identifying genera because the keys are the best available and have now been brought up to date. For this reason and because of space limitations we are not including keys in this work. We do include tips to identifying each species, when possible, under their entries. Bradley (2013) is very useful, with keys to the families and color illustrations of 469 species in all of the then known families from North America. It is a good place to start as the illustrations of whole spiders are useful to narrow the field. After the family is determined, Ubick et al. (2017) can be used to determine the generic placement. As far as state or local guides are concerned, Jackman (1997) is the most up to date (and only) guide for Texas, but there are no guides for Arizona or New Mexico. If a species determination is critical, as in spider bite, a specimen should be sent to a specialist.
Literature Cited
Bradley, R. A. 2013. Common Spiders of North America. University of California Press, Berkeley.
Dippenaar-Schoeman, A.S. & Jocqué, R. 1997. African Spiders, An Identification Manual. Plant Protection Research Institute Handbook 9, Agricultural Research Council, Pretoria.
Kaston, B. J. 1978. How to Know the Spiders. McGraw Hill, Boston.
Levi, H. W., and L. R. Levi. 1968. A guide to Spiders and Their Kin. Golden press, New York.
Platnick, N. I. 2013. The World Spider Catalog. American Museum of Natural History, New York City. http://research.amnh.org/iz/spiders/catalog/
Ubick, D., P. Paquin, P. E. Cushing, and V. Roth (eds.) 2017. Spiders of North America: An identification manual, 2nd ed. American Arachnological Society.
