Identification of harmful and non-harmful spiders in central Ohio

Just a note about allergic reactions to spider venom- in order to have an allergic reaction a series of rare events need to happen. First you need to be bitten by a spider. Second, your immune system needs to decide that an allergic response is the best way to handle this particular type of venom in the future and make allergic antibodies (aka IgE) that can attach to that specific type of venom. Third, that same species of spider (or maybe another species within the same genus) needs to bite you again. Fourth, the allergic antibodies made in response to the previous dose of venom must bind to the newly injected venom, and trigger an inappropriate response from mast cells that fails to localize the venom.

Spider bites are fairly rare, but do happen. Most people require more than one exposure to a particular type of venom for their immune system to produce allergic antibodies against it, and it is very rare to have multiple bites from a single species of spider. Even then, the allergic reactions to arthropod bites and stings are usually appropriate and the reaction remains localized: an itchy red area at the site of the bite.

There are a handful of cases in which systemic allergic reactions to spider venom have been documented in a convincing way, but these reactions are so rare that they are probably not worth mentioning. Similarly, most recluse spider bites are similar to what you have described for your bite- a few days of a small, sore bump that gets better over time. Necrotic lesions almost never happen, and when they do, are concerning for something else going wrong with that person's immune system. Widow bites are usually not associated with problems, but the neurotoxins are capable of deranging the human nervous system, and this occasionally requires medical intervention.

Different people have different thresholds for what they consider to be “dangerous.” I usually reserve the term dangerous to refer to life-threatening reactions, but others think that several days of throbbing pain warrants the designation of dangerous. It is really a matter of opinion I suppose. Most spiders are capable of inflicting a painful bite similar to what you experienced. For that matter most predacious arthropods with piercing mouthparts are capable of giving a painful bite. I was once even traumatized by a grasshopper bite, although perhaps my pride was injured more than my skin. I think that fear is the most common consequence of spider bites, but ironically, spider bites even inspire fear in those that have not been bitten.