Marma wesolowskae

The spider is small. The male has a typical total length of 3.38 mm (0.133 in). The brown carapace is 1.96 mm (0.077 in) long and 1.31 mm (0.052 in) wide, and covered in scales. The abdomen has a thick brown stripe down the middle of its back and pale edges.^[6] The chelicerae have two forward and one back teeth. The back tooth has more than one cusp.^[7] The legs have dark markings. The palpal bulb has an elongated retrolateral tibial apophysis that is reminiscent of a finger.^[6] The embolus is long, thing and has a curved end. The embolic disc is narrow and has a straight spike-like protrusion that extends as far as the embolus.^[8] The palpal bulb has orange scales.^[9]

The female is longer, with a typical length of 4.01 mm (0.158 in). It has a similar carapace, although larger at 1.9 mm (0.075 in) long and 1.43 mm (0.056 in) wide.^[6] The abdomen is also paler. The two copulatory openings are close to each other and to towards the back of the epigyne.^[10] The copulatory ducts are long and complex, circling around the spermathecae.^[11]

The spider is similar to the related Marma nigritarsis and Marma pipa. The spider shares attributes with these species, including the way that the spermathecae are circled by the copulatory ducts. The males have a narrower emobolc disc. Marma wesolowskae has its copulatory openings placed more to the back of the epigyne, and have a projecting border at the back of the eipigynal plate.^[6] It differs from Marma pechichon in that the copulatory ducts circle only once around the spermathecae.^[12] Marma sinuosa can be distinguished by the straight protrusion on the embolic disc on Marma wesolowskae.^[13] The orange scales on the palpal bulb are also unusual, the other species generally being white,^[9]

Marma wesolowskae is endemic to Brazil.^[1] The male holotype for the species was found in the Buíque in 2019. The female paratype was found nearby. The spider has only been found in Pernambuco. The species lives on sandstone.^[10] The spider's colours are similar to its environment, enabling it to hide on the rock.^[2]