Diphya Nicolet 1849
Creators: name: Omelko, Mikhail M.
name: Marusik, Yuri M.
name: Lyle, Robin
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Tetragnathidae
Diphya

description: Genus Diphya Nicolet, 1849
Diphya Nicolet, 1849: 406; Simon 1894: 744; Tanikawa 1995: 102; Álvarez-Padilla & Hormiga 2011: 756; Marusik & Omelko 2017: 2.
Type species. Diphya macrophthalma Nicolet, 1849.
Diagnosis for the Afrotropical species. Diphya differ from other tetragnathid genera occurring in the Afrotropical Realm by having the posterior and anterior lateral eyes twice as large as the anterior medians (Figs 3 A–I vs. eyes subequal in diameter), widely spaced lateral eyes (Figs 3 A–I vs. eyes almost touching each other), and the presence of a row of stiff prolateral setae on legs I–II (Figs 4H, 5 A–D), which are lacking in other genera. In addition, males have modified ventral spines on metatarsi I (Fig. 6) that are lacking in males of other genera.
Description for species occurring in South Africa. Small spiders, males TL 2.41–2.88, CL 1.34–1.61, females TL 3.17–3.75, CL 1.25–1.71. Carapace with distinct and variable pattern or almost uniformly dark colored, covered with fine embedded setae, each seta originates from fine papilla. Fovea indistinct. ALE and posterior eyes more than twice larger than AME, posterior eyes separated by one or less than one diameter; lateral eyes spaced by more than one diameter; clypeus smaller than ALE diameter. Sternum with pattern composed of dark median band or spot and dark margins, or just dark margins, and can be uniformly dark colored. Chelicerae with 3 promarginal and 3 or 4 retromarginal teeth; some species have distinct mesoprolateral ridge (Mr). Legs uniformly colored or with annulations. Legs I and II with prolateral row of stiff inflexible setae. Spines distinct. Male with modified (short and thick) unpaired ventral spines on metatarsi I. Femur I covered with setae as on carapace, with small hemispherical bases (Fig. 10C); tibia I with long ventral setae; tarsi I in D. simoni with 2 rows of modified ventral setae (Fig. 10I); tarsal claws I uniseriate, prolateral claw with prolateral row of teeth in proximal part, bent into retrolateral side anteriorly; retrolateral claw with straight row of prolateral teeth (Fig. 10 J–K).
Abdomen with distinct and similar basic pattern (exception D.vanderwaltae sp. nov.), although it can vary within the same species.
Male palp. Femur short, shorter than cymbium; patella unmodified; tibia as long as wide or slightly longer than wide, widening distally. Cymbium oval or subsquare-shaped, with strong dorsal process; paracymbium small and short, wide basally, with clavate head, lacking setae. Subtegulum large; visible part of tegulum (Te) small, stripelike, most of it hidden by subtegulum and broad and large conductor. Conductor with fold wrapping terminal part of long embolus; embolus with broad base, forming loop (El) over 360º.
Epigyne. Wider than long, with transverse septum, lacking fovea, with distinct copulatory openings. Septum with stem and wide base; stem with lateral hoods (pockets) or without, central part of septum can be protruding over epigynal plate; receptacles globular or oval, converging anteriorly, almost touching or spaced by less than one radius; copulatory ducts indistinct.
Species-specific characters. Species can be separated by their own pattern, presence or absence of annulation of legs, spination, number of cheliceral teeth, shape of cymbium, shape and size of dorsal cymbial process, shape of conductor, relative length of embolus (and its loop), shape of septum, relative width of septal stem, and the presence or absence of lateral hoods of the stem. Males also differ by the relative size of ventral metatarsal spines.
Composition. So far, five species are recognized in South Africa: D. foordi sp. nov. (♁ ♀), D. leroyorum sp. nov. (♁), D. simoni (♁ ♀), D. vanderwaltae sp. nov. (♀) and D. wesolowskae sp. nov. (♁ ♀).
Distribution. Distribution records of all species found in South Africa are shown in Fig. 14. Diphya simoni has the widest range and known from the Cape Peninsula in the southwest to the Kruger National Park in the northeast, followed by D. foordi sp. nov. with the second widest range. Diphya wesolowskae sp. nov. is restricted to the eastern part of the country and two remaining species are known from single localities.
Relationships. All South African species seem related to each other and have similar copulatory organs, but differ significantly from the generotype D. macrophthalma Nicolet, 1849 (see Marusik & Omelko 2017) and other species occurring in southern South America. The male palps of African species lack a tibial apophysis, which is present in the American species (unique character within the family); have a short hairless paracymbium (vs. long and bilobate, longer than tibia and bearing several setae); and the fold of the conductor hides the terminal part of the embolus (vs. embolus not hidden). Epigynes also differ significantly between African and American species: African species have a septum, which is lacking in the Neotropical species. Further, the latter lack a median plate and fovea (atrium) and have a single copulatory opening, while in African Diphya a fovea is absent, and the copulatory openings are located on different sides of the septum. In addition, African Diphya have no distinct copulatory ducts and have simple receptacles, while epigynes of Neotropical species have copulatory ducts and the receptacles are bilobate (at least in the generotype). This suggests that the African species should be placed in a separate genus.
description: Published as part of Omelko, Mikhail M., Marusik, Yuri M. & Lyle, Robin, 2020, A survey of Diphya Nicolet, 1849 (Araneae: Tetragnathidae) from South Africa, pp. 259-279 in Zootaxa 4899 (1) on pages 260-261, DOI: 10.11646/zootaxa.4899.1.14, http://zenodo.org/record/4400533