Direct chromosomal preparation protocol from old world tarantulas (Araneae, Theraphosidae)

The Theraphosidae (Thorell, 1869) is the most prevalent family in the suborder Mygalomorpae, but little is known about their cytogenetics, nor have the chromosomes of old-world tarantulas been studied. This study aims to develop an efficient protocol for chromosomal tarantula preparation in which chromosomes are extracted directly from the internal organs of spiders following in vivo colchicine treatment. Chilobrachys (Karsch, 1892) and Cyriopagopus (Simon, 1888), which belong to different subfamilies, were chosen as validation models.The results indicate that the protocol for preparing chromosomes from both subfamilies is effective, suggesting that Southeast Asian tarantulas are probable to have bi-arms chromosomes and a high proportion of diploid number (2n). Interestingly, diploid chromosomes contain chromosomal gaps on many chromosomes, which will be investigated in the future to facilitate a greater understanding.