Carebara oni ( Terayama, 1996 )

Matsuura, Kohei, Hosoishi, Shingo & Pham, Hong Thai, 2025, Taxonomic revision of the Carebara oni species group, with descriptions of two new species from Vietnam (Hymenoptera, Formicidae, Myrmicinae), Deutsche Entomologische Zeitschrift 72 (2), pp. 377-393 : 377-393

Carebara oni ( Terayama, 1996)

Fig. 10 A – F

Oligomyrmex oni Terayama, 1996: 20, major worker, minor worker.

Combination in Carebara .

Terayama, 2009: 151.

Non-type material examined.

Japan • 7 major workers and 4 minor workers; Okinawa pref., Nago-shi, Katsuu-dake , 370 m alt.; 28. Sep. 2023; Kh. Matsuura and S. Hosoishi leg.; decayed wood; colony KM 23-OKN-1 ; KUEC . 1 major worker; Okinawa pref., Kunigami-son, iji, Ohkuni forestry road ; 29. Sep. 2023; Kh. Matsuura and S. Hosoishi leg.; decayed wood; colony KM 23-OKN-2 ; KUEC . 4 major workers; Okinawa pref., Kunigami-son, iji, Ohkuni forestry road ; 19. Sep. 2024; T. Nakazono leg.; under a stone; KUEC .

Diagnosis of worker.

Major worker: Dorsal surface of promesonotum smooth and shiny. Lateral surface of pronotum entirely smooth and shiny. Lower portion of mesopleuron largely smooth and shiny. Reticulation on dorsal surface of propodeum indistinct. Posterodorsal margin of petiolar node in profile view strongly curved. Minor worker: Vertex, lateral propodeum, and dorsal surface of petiolar node smooth and shiny.

Measurements

(in mm) and indices. Major worker (n = 12): TL 2.76–3.44, HL 0.65–0.89, HW 0.63–0.82, SL 0.35–0.41, EL 0.03–0.09, ML 0.73–0.92, MW 0.35–0.46, PSL 0.11–0.17, PSD 0.03–0.05, PL 0.34–0.44, PH 0.22–0.27, DPW 0.17–0.25, PPL 0.22–0.28, CI 90–98, SI 42–54, PI 1 147–171, PI 2 51–62. Minor worker (n = 4): TL 1.24–1.31, HL 0.38–0.39, HW 0.34–0.36, SL 0.22–0.23, EL 0.01–0.02, ML 0.37–0.39, MW 0.20–0.23, PSL 0.05–0.06, PSD 0.02, PL 0.15–0.17, PH 0.10–0.11, DPW 0.07–0.08, PPL 0.08–0.09, CI 88–94, SI 57–61, PI 1 146–151, PI 2 47–49.

Remarks.

The original description and figure ( Terayama 1996) closely match the specimens examined. Based on worker morphology, the specimens from Okinawa are herein determined as C. oni .

Five intermediates are recognized for the major worker of this species (Fig. 11 ). Eyes are smaller and reduced in intermediate 1, while intermediates 2 to 5 have larger and multi-faceted eyes. States of ocelli are diverse in each intermediate: one indistinct ocellus in intermediate 1; one median ocellus and one lateral ocellus in intermediate 2; one ocellus in intermediate 3; one ocellus and two horns in intermediate 4; one ocellus and two lateral ocelli in intermediate 5. Promesonotal suture in dorsal view is gradually getting convex forward from intermediates 1 to 5. Propodeum unarmed in intermediates 5, while others have short spines. Body color of intermediate 1 is in yellow.

Figures

Figure 10. A – F. Carebara oni (Terayama). A – C. Major worker (KUEC) from Japan; D – F. Minor worker (KUEC) from Japan. A, D. Profile view of body; B, E. Head in full-face view; C, F. Dorsal view of body.

Figure 11. A – O. Intermediates of Carebara oni (Terayama). A – C. Intermediate 1; D – F. Intermediate 2; G – I. Intermediate 3; J – L. Intermediate 4; M – O. Intermediate 5. A, D, G, J, M. Head in full-face view; B, E, H, K, N. Profile view of body; C, F, I, L, O. Dorsal view of body.