Arachnoiden Tarantulas


Arachnoiden supplies tarantulas from around the world to hobbyists, breeders, and resellers. We are located in Massachusetts. The majority of our species are imported, always in accordance with USFW and US Customs regulations. For ease of use, you will find species organized on a single page in growth categories: spiderling, juvenile (Jvn), semi-adult (SeA)/subadult (SA), and adult. All specimens older than juveniles are sexed.

The tarantula keeping and breeding hobby is so exciting. It is growing and changing quickly, sometimes stumbling along the way. Please check to see if a photo and text accompany the species in which you have interest. We try to provide the most current, species-specific information and explain misleading trends in identification, collection locale, and behavior. It is necessarily a work in progress. The information used is collected from a variety of sources, typically overseas collectors, breeders, exporters, arachnologists, and of course, our own experience. Additional sources include original scientific manuscripts, hobby and arachnology textbooks, and the Journal of the British Tarantula Society. We welcome information from any interested party and will attribute facts or photos used in a posting . . . and often offer a freebie!

Feel free to use the Contact tab or post on our Facebook page with questions, ideas, comments, reviews, and/or photos:


Buying Guide


For those of you new to the hobby, welcome! Here are a few tips to facilitate your venture into this exciting field:

There are many sources of reliable information, but time-tested The Tarantula Keepers Guide (TKG) by Stanley and Marguerite Schultz has helped thousands of hobbyists with the basics. It is worth reading before your first purchase.

Whether you plan to keep one species or one hundred, spiderlings are generally the most economic investment. We are happy to provide customers with spiderling husbandry advice.

Tarantulas aren’t easily sexed as spiderlings, but with increasing size, sexing by molt or ventral examination becomes easier and more reliable. Upon reaching reproductive age, or adulthood, males generally live for only another year. Females live for many more years, upwards of 25 for some species. Collectors typically prefer females, whilst breeders obviously both sexes. From a hypothetical 50:50 sac, a randomly chosen spiderling has a 50% chance of being female. Two spiderlings increase the odds of one female to about 75%. With three the odds are close to 90%. Emerging data on tarantula egg sac sex ratios in different species however, is making this statistic problematic. Sometimes there appears to be male bias, upwards of 60-70%, depending on species and perhaps other factors. More on this subject as we learn it.

If you decide to purchase larger specimens, possibly to eventually pair with a tarantula already in your possession, you will notice we have different sizes of several species. After you have confirmed we have your species, you will want to know size. We use a single, anterior-posterior leg-span measurement with the spider in rest position.

With adult males (AM) we list molt dates when available. Knowing when a male is penultimate (subadult (SA)) can be tricky. Size can be helpful, but exceptions abound. As with males, females sometimes mature at unexpected sizes. Upon sexual maturation, most young adult females generally have potential to increase in size with further molts.


Thank you everyone.