Aenictus hitai, Gómez, 2022

Gómez, Kiko, 2022, A revision of the Afrotropical species of the Dorylinae ant genus Aenictus (Hymenoptera: Formicidae) based on the worker caste, Belgian Journal of Entomology 124, pp. 1-86 : 52-54

Aenictus hitai sp. nov.

Zoobank: 3F5DF2FF-03C8-452A-B32E-4B66E71C43A4

( Figs 34 A–D , 35 A–D , 36 )

Holotype worker, KENYA: • Kajiado 20/09/1978 (Darlington, I.) (1w) [ NHMUK012849036 , top] BMNH.

Paratype workers: • same data, (2w) [ NHMUK012849036 , middle, bottom], (9 pins, 3w each) [ NHMUK012849307 to NHMUK012849315 ] BMNH .

DIAGNOSIS. This species can be separated from the rest of the mariae complex species due to defined dorsopropodeal sculpturation, similar to that in the mesopleurae and lateropropodeum. It is present even in the minor workers as an alutaceus reticula. The subpetiolar process is also quite specific, with very small (relative to petiolar dome) elliptic bulk and a poorly developed lamella. Some larger individuals may present a larger lamellae, similar to that present in A. mariae , but in these the sculpturation is always clearly reticulated, never smooth as in A. mariae or A. boltoni sp. nov.. Its dense setation is also quite distinct from the other three species in the group.

DESCRIPTION ( Figs 34 A–D , 35 A-D). WORKER. HL: 0.49 [0.37-0.60]; HW: 0.42 [0.28-0.56]; SL: 0.25 [0.17-0.32]; WL: 0.68 [0.50-0.87]; PL: 0.18 [0.13-0.23]; PH: 0.12 [0.09-0.17]; PPL: 0.13 [0.09-0.18]; PPH: 0.10 [0.07-0.15]; CS: 0.46 [0.32-0.58]; CI: 85 [77-93]; SIL: 51 [47-54]; SIW: 60 [54-66]; WL/HW: 161 [150-175]; PI: 148 [135-166]; PPI: 129 [118-149]; CSR: 178; (n=16).

Polymorphic (CSR>170). Head variable from elongate and rectangular in the minor workers (CI~78) to roundly quadrate with convex lateral sides and slightly widest at the middle in the major workers (CI~100). Occipital line straight. Scapes short, just reaching the median line of the head when laid back (SIL~0.52). Funicular segments wider than long, the subapical quadrate, apical about twice longer than wide. Frontal carinae small, not surpassing the torulus and fused between the antennal sockets. Frontal ridges developed distally and projecting over the clypeus in frontal view. Mandibles with a long, sharp apical tooth and 3–7 denticles.

Almost flat in lateral view and subrectangular in dorsal view; mesopropodeal suture very weak with propodeum and metanotum almost forming a continuous line. Transverse mesopleural groove present. Mesometapleural suture present but very weak. Propodeal declivity flat, with posterodorsal and posterolateral ridge from present as a continuous line in major workers but weak, to absent in some minor workers with all intermediate forms present; posterodorsal ridge never projecting as a shelf in lateral view.

Petiole sessile with anterolateral ridges present, anterodorsal and dorsolateral ridges absent. Petiolar dome with a short anterior face sloping at 60º approximately, anterodorsal angle rounded and obtuse, posterodorsal angle right, both rounded, dorsal face horizontal. Postpetiole with anterior and posterior vertical faces, and horizontal dorsal surface, both angles right and rounded. Both domes without carinae or ridges of any kind. Subpetiolar process developed and variable, with a bulky small elliptical process followed by a triangular lamella variable intranidally, usually present only in its anterior slope and directed forward, more or less developed, but always present.

All body surfaces smooth and shining except for meso, metapleurae and propodeum variable from alutaceus smooth in minor workers to strongly reticulated-punctuated in some major workers. Propodeum dorsally with the same sculpturation than laterally. Mandibles from slightly to strongly shagreenate. Overall colour from light yellow to brown. As a general rule, smaller individuals are lighter and smoother than larger ones.

Whole body except propodeal dorsum covered with a short decumbent to reclinated small white setae, very abundant. Dorsum of propodeum bare except for its anterior and posterior borders. The length of the setae smaller than petiole height. Another layer of longer, sparser erect setae present in upper half of head, mesosoma, metasoma and gaster, clearly longer than petiole height. Scapes and funiculus with decumbent to semierect pilosity, shorter than scape width. No pubescence noted.

DERIVATIO NOMINIS. The species name hitai is Latinized noun in the genitive case, dedicated to Dr. Francisco Hita-Garcia, always encouraging and friendly, set aside his vast knowledge of Afrotropical Fauna.

OTHER MATERIAL EXAMINED. MOZAMBIQUE: • Cabo Delgado, Namoto forest 35m 19/03/2016 (B.L. Fisher et al.). dry forest (3 pins, 1w each), ex soil [ CASENT0777862 to CASENT0777864 ] CASC • Cabo Delgado, Parque Nacional Quirimbas , Mareja Reserve 240 m 26/02/2016 (B.L. Fisher et al.). miombo at base of inselberg (3 pins, 1w each), ex soil [ CASENT0778949 to CASENT0778951 ] CASC; same data (2w) [ CASENT0778952 ] CASC .

DISTRIBUTION. Eastern African, known from Mozambique and Kenya ( Fig. 36 ).

Figures

Fig. 34. Aenictus hitai sp. nov., minor, holotype (NHMUK012849306). A, head, dorsal view. B, habitus, lateral view. C, mesosoma, petiole and postpetiole, lateral view. D, mesosoma, petiole and postpetiole, dorsal view.

Fig. 35. Aenictus hitai sp. nov., major worker (CASENT0777863). A, head, dorsal view. B, habitus, lateral view. C, mesosoma, petiole and postpetiole, lateral view. D, mesosoma, petiole and postpetiole, dorsal view.

Fig. 36. Distribution of A. hitai sp. nov.