The arresting specimen you could see above was the first document example of a European wolf spider with gynandromorphic characteristic : one side of its body is distaff , while the other is male .

The guinea pig first came to light in 2014 at a lab at the University of the Republic in Uruguay when a team of bug experts was observing a crowd of orange baboon tarantulas ( Pterinochilus murinus ) that had just molted into maturity .

After emerging from its former exoskeleton , one individual revealed a particularly interesting appearance . Perfectly separate down the centre , the proper side was hairier and had somewhat chunkier limbs while its left side was unornamented and scrawny . A tight review revealed that the right side of the body was female , while the left side was virile .

This is known asgynandromorphism , a genetical term in which an being is born with both male and distaff characteristics . It ’s been reported in a change of different animals , fromstick insectsandbeestoan array of birds , but this was the first metre it had been scientifically documented in a Mygalomorphae tarantula .

ab initio , all seemed perfectly well with the unique tarantula and the researchers noted that the someone was seemingly unmoved by its condition .

“ The gynandromorphic Lycosa tarentula walked and fed normally . At least , we did not comprehend any trouble in its everyday behaviors,”Fernando Pérez - Miles , subject field source and entomologist at the University of the Republic , told IFLScience .

However , as it aged , some problem started to arise .

The hermaphrodite underwent a ecdysis after the maturation molting , and its manly sexual reed organ suffered a contortion .

“ There are several peculiarities in the gynandromorph . In European wolf spider , male do not continue to molt after their ontogenesis , when their sexual organ , palpal bulbs , come forth . This is due to a morphological bottleneck , as the shape of the palpal bulb would make it difficult to shed those organs . However , female continue to molt after extend to maturity . The gynandromorph undergo a molt after the maturation molt , and its male sexual pipe organ suffer a contortion , ” excuse Pérez - Miles .

The researchers also observe that the gynandromorph individual was vulnerable to aggression from others , although that ’s perhaps not too surprising since the species is known for its feisty conduct .

“ Another speciality was that we experimentally confronted the androgyne with females on four social function ; on none of these occasion did it motor inn , nor did the female person show any sexual reaction . In one clash , the epicene person was attack by a female person , who hurt one of its legs , ” he added .

Despite these difficulties , the somebody managed to inhabit to a relatively normal age .

It ’s not utterly well-defined what causes gynandromorphism in any species , although it ’s know to occur due to abnormal cell division and the sequestration of the intimate chromosome during early development .

In beast that use X and Y chromosomes to mold an mortal ’s biologic sex ( female typically with XX and male person typically with XY ) , some gynandromorphic individuals will have some cells that may carry an 10 chromosome from one parent , while others may have a Y chromosome from the other parent . This results in mosaicism , in which cell within the same somebody have a dissimilar genetic make-up .

Spiders have importantly more complex sexual activity chromosome organization , with varying constitution of sexual chromosomes across different metal money . This complexity had previously led scientist to assume that gynandromorphy was extremely rare in tarantulas . However , as always , nature is full of surprising exception to the rule .

The subject study was first report inThe Journal of Arachnologyin 2017 .