Royidris peregrina

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Royidris peregrina
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Crematogastrini
Genus: Royidris
Species group: notorthotenes
Species: R. peregrina
Binomial name
Royidris peregrina
Bolton & Fisher, 2014

Royidris peregrina casent0209249 p 1 high.jpg

Royidris peregrina casent0209249 d 1 high.jpg

Specimen Labels

As well as being found running on barren rocks, this species has also been discovered in savannah shrubland and burned savannah.


A member of the notorthotenes species group. Bolton and Fisher (2014) - This species closely resembles Royidris gravipuncta, but has much less strongly developed sculpture, and has relatively slightly longer scapes and metatibiae (SI and MfL/HW in gravipuncta 95–107, and 0.95–1.05, respectively). In addition, peregrina has the dorsum of the postpetiole unsculptured, and the first gastral tergite is glassy smooth, lacking superficial microreticulation. In gravipuncta the dorsum of postpetiole is superficially reticulate-punctulate, and the first gastral tergite is usually obviously superficially microreticulate, at least on the basal half and usually everywhere.

Keys including this Species


Endemic to Madagascar.

Latitudinal Distribution Pattern

Latitudinal Range: -21.34109° to -21.34109°.

Tropical South

Distribution based on Regional Taxon Lists

Malagasy Region: Madagascar (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.




Images from AntWeb

Royidris peregrina casent0206165 h 1 high.jpgRoyidris peregrina casent0206165 p 1 high.jpgRoyidris peregrina casent0206165 d 1 high.jpgRoyidris peregrina casent0206165 p 2 high.jpgRoyidris peregrina casent0206165 l 1 high.jpg
Male (alate). Specimen code casent0206165. Photographer Estella Ortega, uploaded by California Academy of Sciences. Owned by CAS, San Francisco, CA, USA.
Royidris peregrina casent0206174 p 1 high.jpgRoyidris peregrina casent0206174 d 1 high.jpgRoyidris peregrina casent0206174 h 1 high.jpgRoyidris peregrina casent0206174 p 2 high.jpgRoyidris peregrina casent0206174 p 3 high.jpgRoyidris peregrina casent0206174 l 1 high.jpg
Male (alate). Specimen code casent0206174. Photographer Estella Ortega, uploaded by California Academy of Sciences. Owned by CAS, San Francisco, CA, USA.


The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

  • peregrina. Royidris peregrina Bolton & Fisher, 2014: 61, figs. 66-68 (w.q.m.) MADAGASCAR.
    • Type-material: holotype worker, 2 paratype workers.
    • Type-locality: Madagascar: Makay Mts, 21.34109°S, 45.18054°E, 500 m., 28.xi.2010, BLF 25314, CASENT0209249 (holotype), barren rock with sparse vegetation, burned grass (B.L. Fisher et al); paratypes with same data but BLF 25303 and BLF 25318.
    • Type-depository: CASC.
    • Distribution: Madagascar.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.



(holotype in parentheses). TL 2.6–3.3 (2.9), HL 0.62–0.76 (0.72), HW 0.52–0.67 (0.60), CI 84–88 (85), SL 0.60–0.72 (0.65), SI 108–118 (108), PW 0.34–0.44 (0.40), WL 0.76–0.96 (0.88) (18 measured).

Antennal club 4-segmented. Mandible longitudinally costulate. Scapes of moderate relative length (SI 108–118; mean SI 113); when laid straight back in full-face view the apex of the scape distinctly surpasses the posterior margin of the head. With head in full-face view the eyes at the midlength of the side of the head capsule. EL 0.16–0.21 (EL/HW 0.30–0.33). Dorsum of head from level of eyes to posterior margin varies from finely reticulate-punctate to almost unsculptured; the sculpture sometimes uniform but frequently reduced in density and intensity dorsolaterally, or effaced in places, or mostly effaced. Promesonotum in profile convex and swollen, the mesonotum posteriorly descends abruptly to a small, weakly incised metanotal groove. In absolute profile the propodeal dorsum is horizontal and flat, or very nearly flat; posteriorly dorsum meets the declivity in a rounded right-angle and the declivity is straight and almost vertical. The whole propodeal dorsum is strongly depressed with respect to the highest point of the promesonotum, which is on a considerably higher level. Pronotum with 3–5 pairs of setae; mesonotum with 3–4 pairs; dorsum of propodeum without setae; petiole node with 2 pairs, one apical, the other on the posterior face; postpetiole with setae dorsally and posteriorly; first gastral tergite with numerous suberect setae. All setae are shorter than the maximum vertical diameter of the eye. Dorsum of pronotum smooth to weakly, superficially reticulate, distinctly less strongly sculptured than the finely reticulate-punctulate propodeal dorsum. Side of pronotum reticulate to weakly reticulate-punctulate, this sculpture less strong than on the densely reticulate-punctate mesopleuron. Metafemur with MfL 0.60–0.74 (MfL/HW 1.08–1.13, MfL/MfH 3.50–3.76). Postpetiole relatively narrow in dorsal view, maximum width 0.16–0.20 (0.30–0.31 × HW). Sides of petiole and postpetiole nodes weakly reticulate-punctulate; dorsum of postpetiole unsculptured. First gastral tergite glassy smooth, without superficial microreticulation. Colour of mesosoma, petiole and postpetiole variable, yellowish brown, orange-brown or medium brown, the head usually somewhat darker than the mesosoma; the gaster always much darker, very dark brown to black.


(gyne). Alate when virgin. Much larger than worker. TL 5.5, HL 0.98, HW 0.84, CI 94, SL 0.78, SI 93, PW 0.68, WL 1.63, EL 0.29 (EL/HW 0.35), MfL 0.84 (MfL/HW 1.00, MfL/MfH 3.82), maximum dorsal length of mesoscutum 0.78, maximum width of mesoscutum 0.74, maximum dorsal width of postpetiole 0.43 (0.51 × HW) (1 measured). Head more coarsely reticulate-punctate than in the worker, and also with fine longitudinal striolae. Mesoscutum more or less smooth along the midline, but on either side with disorganised superficial reticulate-punctation, upon which are superimposed scattered larger punctures. Mesoscutellum with similar but much reduced sculpture, almost smooth. Propodeal dorsum reticulate-punctate and with fine transverse costulae. Petiole, postpetiole and first gastral tergite finely reticulate-punctate, on the first gastral tergite the sculpture densest and coarsest in the basal half, becoming weaker and more superficial posteriorly. Side of pronotum and mesopleuron very weakly reticulate-punctate, metapleuron and side of propodeum much more strongly so. Propodeum terminates in a pair of broadly triangular, tooth-like angles. All dorsal surfaces except propodeum with numerous fine setae; propodeum has one erect pair present. Colour as in worker.


Known from only two specimens; gaster of the first missing, head and gaster of the second missing. Smaller than worker, much smaller than queen. HL 0.47, HW 0.41, WL 0.94. Head not dorsoventrally flattened, the clypeus bulging in profile. Ocelli at highest point of vertex; outline of dorsum descends steeply behind ocellus to the sharp occipital carina; with head in profile the length of the cephalic dorsum between the posterior ocellus and the occipital carina is greater than the length of the ocellus. See also under diagnosis of genus.

Type Material

Holotype worker, Madagascar: Makay Mts, 21.34109°S, 45.18054°E, 500 m., 28.xi.2010, BLF 25314, CASENT0209249, barren rock with sparse vegetation, burned grass (B.L. Fisher et al.) (California Academy of Sciences). Paratypes. 2 workers with same data as holotype but one BLF 25303, CASENT0209248, the other BLF 25318, CASENT0203840 (CASC).


  • Bolton, B. & Fisher, B.L. 2014. The Madagascan endemic myrmicine ants related to Eutetramorium (Hymenoptera: Formicidae): taxonomy of the genera Eutetramorium Emery, Malagidris nom. n., Myrmisaraka gen. n., Royidris gen. n., and Vitsika gen. n. Zootaxa 3791:1–99. doi:10.11646/zootaxa.3791.1.1

References based on Global Ant Biodiversity Informatics

  • Bolton B., and B. L. Fisher. 2014. The Madagascan endemic myrmicine ants related to Eutetramorium (Hymenoptera: Formicidae): taxonomy of the genera Eutetramorium Emery, Malagidris nom. n., Myrmisaraka gen. n., Royidris gen. n., and Vitsika gen. n. Zootaxa 3791(1): 1-99.