I stopped by school late Sunday morning to determine the status of several tarantulas that are clearly in the late stages of pre-molt. After last week’s successful Mexican redknee tarantula (Brachypelma smithi) gender determination, I was eager to try it again with the still moist exoskeleleton of the larger Mexican redknee tarantula or either of the Honduran curlyhair tarantulas (Brachypelma albopilosa).
Nothing was happening, so I watered the animals and left for a school-related afternoon meeting.
The next morning I arrived to see the larger Mexican redknee tarantula had successfully molted. Unfortunately the exoskeleton was fairly dry. I followed the exoskeleton rehydration procedure shown in a YouTube video entitled “Sexing a Tarantula Tutorial 2,” set up the camera with the macro lens, extension tube and lighting system, and began the slow, deliberate rehydration and examination process.
The moistening process, combined with my first attempt at unfurling the dried abdomen with the assistance of two dissecting pins, caused the ventral region of the dried abdomen to tear. In retrospect, the tearing actually made the spreading of the rest of the anterior region of the abdomen much easier. I took about 25 pictures in manual mode, transferred my images from the memory card to my laptop, and sharpened each image.
I was pleased to get pretty spectacular detail in four of the images. A little bit of sharpening allowed me to see the blatantly obvious spermathecae of this exoskeleton. Both of the large Mexican redknee tarantulas have now been determined to be female.
Gender was confirmed by Jen Newman, Joe Mastous, Paul Laniczak and Jamie Lessee. Jen suggested that the oothecae appeared sufficiently sclerotized that the spider may be breedable at this point. I’ll wait another molt before I start to even think about pursuing that option.
Another new skill for me, and I’m pretty pleased with the results so far!