The December Spider of the Month (SOTM) is this beetle-mimic jumping spider (Pachyballus miniscutulus; Salticidae), photographed by Rudi Steenkamp (me).
The spider, about 3 mm long, was found by Ruan Booysen during a spider walk held during the Spider Club’s 50th birthday event at the Free State National Botanical Garden in Bloemfontein. It was found among some field grass, which is also where their model, tiny black ladybird beetles (Exochomus sp.), are also found.
Pachyballus species are Batesian (defensive) mimics of beetles (mostly ladybird beetles), which means they mimic another organism to avoid predation, as opposed to aggressive mimics that prey on their models. Many predators would avoid eating these beetles due to their chemical defence, which makes them unpalatable. These predators will therefore also think twice before eating one of these jumping spiders.
There are only nine recorded Pachyballus species in the world, of which eight occur only in Africa (the other species being from New Caledonia). South Africa has four species. Four of the nine species were described in 2020 by Wesołowska, Azarkina and Wiśniewski.
Pachyballus basically means “thick jumping spider”, from the Greek pachys (thick, stout, large – think thick-skinned pachyderms like elephants, rhinos, and hippos) and the Greek verb ballizō (to jump or to dance – think ballerina). There is also another jumping spider genus named Ballus. The specific epithet, miniscutulus, means “small shield”. I’m not sure if this refers to the entire spider being a “small shield” or to another part of their anatomy.
This is the fourth time a Pachyballus species has won SOTM, the previous three times being in 2021, 2022, and 2023. Of 171 people who voted, this photo received 97 (57%) votes. I think this is my seventh (or perhaps eighth) SOTM.
Thanks again to everyone who voted! Later this month, we will have the Spider of the Year (SOTY) poll.