Males are much smaller than females, and they amputate one of their palps before maturation, entering their adult life with only one palp.[3] Though it is uncertain why they do this, it may be done to increase mobility, as the palps are disproportionately large compared to the size of the body. It may also be done because only one palp is needed.
Females of the Yemeni species T. argo tear off the single remaining palp before feeding on males. The palp remains attached to the female's epigynum for about four hours, continuing to function despite being separated from the male's body.[4]
Species
As of April 2019[update] it contains twenty-four species:[1]
^Chamberlin, R. V.; Ivie, W. (1934). "A new genus of theridiid spiders in which the male develops only one palpus". Bulletin of the University of Utah. 24 (4): 1–18.
^Vollrath, F.; Parker, G.A. (1992). "Sexual dimorphism and distorted sex ratios in spiders". Nature. 360 (6400): 156–159. doi:10.1038/360156a0. S2CID4320130.
^Knoflach, Barbara; van Harten, Antonius (2001). "Tidarren argo sp. nov. (Araneae: Theridiidae) and its exceptional copulatory behaviour: emasculation, male palpal organ as a mating plug and sexual cannibalism". Journal of Zoology. 254 (4). Cambridge University Press: 449–459. doi:10.1017/S0952836901000954.
