Artema and pholcid body size
Published in Zootaxa, 2021,

Most pholcids are delicate, small-bodied but long-legged spiders, ill-reputed among collectors for their annoying tendency to produce irresolvable tangles of legs in collecting jars. Representatives of Artema Walckenaer, 1837 do not fit this cliché. They are the giants among pholcids, with long but strong legs that may easily reach the span of a man’s hand.

Geographically, the genus is largely restricted to Central Asia, the Middle East, the Arabian Peninsula, and the eastern Mediterranean. One species has previously been known from West Africa. Here I describe the first known Moroccan species, which extends the known distribution of the genus to the northwestern limit of the African continent.

With respect to carapace width, the new species is the largest pholcid species described so far. The second to fifth largest species are also representatives of Artema, followed by two species of Ixchela and two further species of Artema. This suggests that representatives of Artema, previously called the giants among pholcids (Aharon et al. 2017), are indeed the largest pholcids with respect to carapace width and probably also with respect to body mass.

A secondary focus of this paper is on the decrease of body size of described species over time. Large organisms are usually easier to find than small ones, so it is unsurprising that large species were on average described earlier than small ones. Pholcids follow this common trend: mean carapace width of newly described species per period of time has fallen from approximately 1.8 mm in the late 18th and early 19th century to approximately 1.1-1.2 mm in the late 20th and early 21st century. Surprisingly, there is no obvious flattening of the curve, suggesting that among the remaining unknown species (some 2,400-4,500 according to Huber & Chao 2019) there will be many small and few large ones. Discoveries of further pholcid species as big as the newly described Artema will likely be very rare.