A brand new variety of tarantula has been discovered and classified by scientists because of their exceptionally large male genitalia.<\/p>\n
The spiders \u2013 who’ve been given the genus Satyrex \u2013 live within the Arabian Peninsula and the Horn of Africa. <\/p>\n
Researchers have identified 4 different species and the most important, the Satyrex ferox, has a leg-span of about 14cm. <\/p>\n
Its palp \u2013 a specialised appendage utilized by male spiders to transfer sperm during mating \u2013 can reach an incredible length of 5cm. This is sort of 4 times longer than the front a part of the body, and almost so long as it longest legs.<\/p>\n
The spiders are highly aggressive and scientists imagine their huge genitals could have evolved to assist them avoid being eaten by females during mating. <\/p>\n A male Satyrex arabicus, present in Saudi Arabia. 4 species have been identified throughout the genus (Picture: Ibrahim Mohssin Fageeh\/Cover Media)<\/p>\n<\/figcaption><\/figure>\n Start your day informed with Metro’s News Updates<\/strong> newsletter or get Breaking News <\/strong>alerts the moment it happens. <\/p>\n<\/p><\/div>\n<\/p><\/div>\n \u2018Based on each morphological and molecular data, they’re so distinct from their closest relatives that we had to ascertain a completely latest genus to categorise them, and we named it Satyrex,\u2019 said Dr Alireza Zamani of the University of Turku, who led the study that discovered them.<\/p>\n \u2018The males of those spiders have the longest palps amongst all known tarantulas.\u2019<\/p>\n The genus name is a mix of Satyr, a part-man, part-beast figure from Greek mythology with exceptionally large genitalia, and the Latin word r\u0113x, meaning \u2018king.\u2019<\/p>\n Ferox, meaning fierce, was chosen for one species as it’s so aggressive.<\/p>\n \u2018This species is very defensive. On the slightest disturbance, it raises its front legs in a threat posture and produces a loud hissing sound by rubbing specialized hairs on the basal segments of the front legs against one another,\u201d Dr Zamani said. <\/p>\n \u2018Now we have tentatively suggested that the long palps might allow the male to maintain a safer distance during mating and help him avoid being attacked and devoured by the highly aggressive female.\u2019<\/p>\n As for the others within the group \u2014 the researchers named S. arabicus and S. somalicus after their respective regions of origin, while S. speciosus gets its name from its vibrant and exquisite coloration. The genus also includes an older species, S. longimanus, originally described from Yemen in 1903 and previously placed in a special genus.<\/p>\n \u2018Satyrex longimanus, despite also having an elongated palp, was formerly classified within the genus Monocentropus, where the male palp is just about 1.6 times the length of the carapace and well inside the standard range of 1.5 to 2 times seen in tarantulas. <\/p>\n \u2018The for much longer palps of S. longimanus and the 4 newly described species were among the many primary characters that led us to ascertain a brand new genus for these spiders, somewhat than place them in Monocentropus. <\/p>\n \u2018So yes, at the least in tarantula taxonomy, plainly size really does matter,\u2019 Dr. Zamani said. <\/p>\n All members of this genus are fossorial, meaning they live underground, in burrows at the bottom of shrubs or between rocks.<\/p>\n The study was published within the open-access journal ZooKeys.<\/p>\n![\"\"](\"https:\/\/metro.co.uk\/wp-content\/uploads\/2026\/04\/coverimages55603073-0b40.jpg?quality=90&strip=all&w=646\")
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