Beneath the surface: A new northern species of Trogloraptor (Araneae: Trogloraptoridae), genetic diversity and natural history

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  Beneath the surface: A new northern species of Trogloraptor (Araneae: Trogloraptoridae), genetic diversity and natural history Abstract We present a morphological description of a recently discovered species of spider in the family Trogloraptoridae from the Columbia River Gorge in northwestern Oregon. The family was previously monotypic (Trogloraptor marchingtoni) and only known from populations near the southwestern Oregon—northern California border. Trogloraptor tulishpun sp. nov. retains the key family synapomorphy, distinctive subsegmented raptorial tarsi, and an oblique membranous division of the basal segment of the anterior lateral spinnerets. Trogloraptor tulishpun is distinguished from T. marchingtoni by its color pattern, clypeal height, vulvar and palp structure. We have found T. tulishpun in four localities in the Columbia River Gorge, which show little mitochondrial sequence divergence from one another, but are highly genetically distinct from T. marchingtoni. Troglo...

An eyeless new species of Monoblemma Gertsch, 1941 (Araneae: Tetrablemmidae) from Venezuela, with a new record of the single-eyed Monoblemma unicum Gertsch, 1941 from the Dominican Republic

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An eyeless new species of Monoblemma Gertsch, 1941 (Araneae: Tetrablemmidae) from Venezuela, with a new record of the single-eyed Monoblemma unicum Gertsch, 1941 from the Dominican Republic

The genus Monoblemma Gertsch, 1941 was recently revised by Martínez (2025) and currently comprises four species, mainly distributed in the Caribbean (World Spider Catalog 2026). Species of the genus exhibit remarkable variation in eye number, ranging from completely eyeless forms, such as Monoblemma becki Brignoli, 1978, to a single-eyed condition, with the eye positioned at the margin of the clypeal declivity in M. unicum Gertsch, 1941, and to four-eyed species, such as M. cambridgei (Bryant, 1940) and M. cubaense Martínez, 2025. In the original description of M. unicum, Gertsch (1941) noted that, because only a single specimen was available, the presence of one median eye might represent an abnormal condition. However, he also suggested that its median position and apparently normal development indicated that it was likely a constant feature of the species, probably resulting from the fusion of the anterior eyes present in species with two or four eyes. The discovery of a second specimen of Monoblemma unicum from the Dominican Republic exhibiting the same ocular condition confirms Gertsch’s hypothesis and supports the interpretation of the single eye as a stable, species-specific character. Additionally, a new eyeless species from Sucre, Venezuela is described based on both sexes, representing the second eyeless species in the genus. An updated distribution map and an identification key to all species of the genus are also provided.

 Martínez, L. (2026) An eyeless new species of Monoblemma Gertsch, 1941 (Araneae: Tetrablemmidae) from Venezuela, with a new record of the single-eyed Monoblemma unicum Gertsch, 1941 from the Dominican Republic. Zootaxa, 5787 (2), 394–400. https://doi.org/10.11646/zootaxa.5787.2.12