Strumigenys xoko Santos-Neto, Chaul & Delabie, 2024, sp. nov.
Creators: name: dos Santos-Neto, Esperidião Alves
name: Chaul, Júlio Cezar Mário
name: Delabie, Jacques Hubert Charles
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Formicidae
Strumigenys
Strumigenys xoko

description: Strumigenys xoko sp. nov. Santos-Neto, Chaul and Delabie
(Figures 4 and 5)
Type material. Holotype worker: BRAZIL, Sergipe: Canindé do São Francisco, − 9.635367, − 37.792324, 25.v.1997, Collected from Aechmea aquilega (Bispo, S.M.) [CPDC 5871, ANTWEB1048665]. Paratype queen, BRAZIL, Bahia: Iguaí, 14.643.056, − 40.147.778, 04.vii.2012 (C. Leite & T. Porto et al.) [CPDC 5780, ANTWEB1048666].
Diagnosis. Basal lamella of mandible triangular, without diastema between it and masticatory margin; eyes large, with 20 ommatidia in total; broad flattened scapes; stand pilosity narrowly remiform, ground pilosity of spatulate setae; petiole and postpetiole entirely reticulate-punctate in dorsal view, first gastral tergite entirely thinly striated, with basigastral costulae shorter than a third of postpetiole disc length.
Geographical Distribution. Brazil (Bahia and Sergipe) (Figure 2)
Description. Worker. HW 0.43, ML 0.12, ML2 0.25, HL 0.59, SL 0.25, OL 0.08, ON 20, WL 0.53, PetL 0.26, A3+A4L 0.65, Prw 0.36, DPetW 0.16, DPetndL 0.12, PosPetW 0.25, PosPetL 0.15, GW 0.51, MtfmL 0.39, MttbL 0.3, CI 73, SI 58, MI 22, TL 2.16. (n = 1). Head. In full-face view, head longer than wide; occipital margin concave, meeting the vertex corners in mild indentations (Figure 4 A); anterior clypeal margin slightly convex; sides gradually diverging posteriorly to the eyes. Mandible triangular, small; basal lamella subtriangular; masticatory margin with 12 teeth, the first originating without a diastemic gap between it and the basal lamella; teeth 1–5 sharp; teeth 1, 2, 4 and 5 subequal, tooth 3 largest; teeth 6 and 7 smaller than the previous; teeth 8-11 reduced denticles, tooth 12, the apical, sharp. Clypeus projecting over base of mandibles. Antennae 6-segmented. Scape broad, dorsoventrally strongly compressed; its anterior margin with three robust spatulate hairs followed by finer spoon-shaped hairs, most of them curved towards its base. Head entirely reticulate-punctate. Ground pilosity composed of subspatulate, appressed hairs; vertex with two pairs of erect setae, remiform, visibly larger than the ground pilosity of the head; apicoscrobal setae subspatulate, shorter in length to the vertex setae. Mesosoma. Entire mesosoma, dorsally and laterally densely reticulate-punctate, without any smooth areas (Figure 5 B). Pronotal humeral pair of setae filiform; mesonotal pair of standing setae absent; ground pilosity on dorsum of mesosoma composed sub spatulated semi-appressed setae, and three pairs of remiform. Metanotal impression forms a shallow groove. Propodeal spine is sharp, long and mostly fused to its subtended lamella, which is large and has a concave posterior margin (Figure 4 B). Legs reticulate-punctate, with hairs finer than those on mesonotum and head. Metasoma. In lateral view, the petiole node is subquadrate, slightly higher than long; in dorsal view, wider than long; anterior margin broader than posterior, reticulate-punctate. Spongiform tissue on petiole ventrally absent, dorsally with a thin fringe on node posterior edge. Postpetiole, in lateral view, with well-developed ventral spongiform tissue; in dorsal view, dorsal edge with a few fringes, not laterally projected. Postpetiole disc reticulate-punctate. Dorsum of the metasoma covered with remiform setae. First gastral tergite entirely striated, with superimposed basigastral costulae shorter than a third of postpetiole disc length, (Figure 4 C).
Queen. HW 0.49, ML 0.13, ML2 0.25, HL 0.67, SL 0.33, OL 0.15, WL 0.76, PetL 0.46, A3+A4L 0.94, Prw 0.42, DPetW 0.21, DPetndL 0.11, PosPetW 0.32, PosPetL 0.15, GW 0.63, MtfrL 0.5, MttbL 0.35. (n = 1). Similar to the worker except for differences typical of the reproductive caste: larger total length, larger compound eyes, presence of three ocelli; larger mesosoma, with small smooth patch on lower mesopleuron and numerous stand setae on mesoscutum and mesoscutellum (Figure 6).
Etymology. The specific epithet refers to the Brazilian indigenous Xokó people, who live on São Pedro Island in the São Francisco River, in the Brazilian state of Sergipe, close to where the type specimen was collected.
Biology. Little can be inferred about the biology of this ant based on the available material. The holotype was collected at the base of an Aechmea bromeliad, suggesting that, like other species within the schulzi species group, this ant prefers nesting in contact with plants.
Comments. The dentition pattern of S. xoko looks like S. schulzi, S. castanea, S. orchibia and S. metrix. S. xoko can be easily identified because, among similar species, it is the only one that has first gastral tergite entirely striated. (Figure 4 C), (Table 1).
description: Published as part of dos Santos-Neto, Esperidião Alves, Chaul, Júlio Cezar Mário & Delabie, Jacques Hubert Charles, 2024, New Species and New Records of Strumigenys Smith, 1860 (Formicidae: Myrmicinae) from the Neotropical schulzi Species Group, pp. 633-648 in Taxonomy (New York) (New York) 4 (3) on pages 641-643, DOI: 10.3390/taxonomy4030032, http://zenodo.org/record/13378268