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Photo#512530
Gynandromorph - Trochosa terricola

Gynandromorph - Trochosa terricola
Whitecourt, Alberta, Canada
May 5, 2011
Size: BL ~ 10 mm
I found this unusual specimen in one of my pitfall traps yesterday.

It is male on the right side and female on the left side, split right down the middle. It has what appears to be half an epigyne on the female side, while the right palp appears to be that of an adult male. In addition, the left/female chelicera is longer and more robust than the right/male chelicera; and, the right/male legs I and II appear to be longer and darker in some segments than their female counterparts (see the ventral view).

Here's a paper (Stratton, 1995) describing a similar example in another wolf spider, Schizocosa ocreata: http://www.americanarachnology.org/JoA_free/JoA_v23_n2/JoA_v23_p130.pdf

Palmgren (1979) estimates a 1-in-17,000 frequency for gynandromorphs among spiders: http://www.sekj.org/PDF/anzf16/anzf16-183-185.pdf

Images of this individual: tag all
Gynandromorph - Trochosa terricola Gynandromorph - Trochosa terricola

hermaphrodite spider
Wow. I knew a kid in high school that shot an 8 point white-tail buck... but when he went to skin it... it was a female. I guess it can happen to any species.

Wow -
amazing! Thanks for posting these photos and information, John!