Can a black widow mate with a hobo spider?

(I can't believe someone previously answered "yes" to this, lol.)

The answer is NO. They wouldn't even be allowed to get that close to one another without one attacking the other. Each individual species has their own way of "talking" to their mate. Most of this communication is done through vibrations of the body parts and pheromones. The pheromones and vibration style of one species is completely different from those of another. They would not mistake one for the other. If a Hobo so much as touched the web of a Black Widow, it would instantly be wrapped up in silk and envenomated, then eaten. The genitalia of Spiders is like a lock and key system. The mating pairs of a species fit together perfectly (the males' pedipalps and the females' epigynes). Something of a different species wouldn't even fit right, making mating impossible... especially in two species so incredibly different. Black Widows and Hobos belong to two completely different families.