In mature males, the pedipalps host the male’s copulatory organs – the palpal bulb. At the base you have the subtegulum, connected to this is the tegulum, which comprises the lower half of the palpal bulb. The bulb then thins into the emboli (shown in this image). This is the part of the bulb, which injects the sperm into the female‘s spermathecae. Many species have keels on their bulbs and these can present in a superior or inferior fashion. Check the Anatomy Poster for more information: or

Testing the 10x Nikon at 6x with the Raynox 250 (normal position) as tube lens. Sony Alpha 7RII + Cognisys StackShot + Nikon 10x MRL00102 @ ~6,2x Stacked from 53 images (30µm; 50µm and 40µm didn’t work so well), Helicon B + C. 3x Ikea Jansjö, bendable concave DIY diffuser + reflector, 40 Megapixel. v1.1