Oecophylla longinoda (Latreille)

Wheeler, W. M., 1922, The ants collected by the American Museum Congo Expedition., Bulletin of the American Museum of Natural History 45, pp. 39-269 : 227-230

Oecophylla longinoda (Latreille)

Plate XX, Figures 1 and 2; Text Figures 58 and 59

Faradje, [[worker]], [[queen]], [[male]]; Malela, [[worker]]; San Antonio, [[worker]] (Lang and Chapin); Katala, [[worker]]; Leopoldville, [[worker]] (J.Bequaert).

The following differences between this species and smaragdina may be noted. In the worker the polymorphism is greater, for not only do the individuals of the same colony show a greater range in size (from 3 to 9 mm.) but the minimae differ more from the mediae and maximae in the shape of the thorax and petiole. The head of the worker longinoda is distinctly more triangular than that of smaragdina , being broader behind, with less convex sides; the eyes are distinctly larger, the mandibles shorter, the clypeus more nearly subcarinate behind, its anterior border sometimes feebly and sinuately emarginate in the middle, the pronotum less convex, the petiole decidedly stouter, more thickened behind, with the stigmata much less prominent when the segment is viewed from above and its ventral surface much more convex anteriorly on the ventral side, when viewed in profile. The sculpture, pilosity, and color are very similar in the two species, but in longinoda the integument is more decidedly opaque, the mandibles are somewhat more coarsely striated, always darker, being concolorous with the posterior portion of the head, at least in the large workers and especially in the dark varieties. The transverse furrow on the second and succeeding gastric segments just behind the anterior border is more pronounced in longinoda .

The female of this species measures 12 to 14 mm. (wings 16 mm.) and is, therefore, distinctly smaller than the corresponding sex of smaragdina , which measures 15 to 17 mm. (wings 18 to 19 mm.). The body of the African species is much more opaque throughout, the wing-veins more heavily bordered with dark brown, and the transverse bands at the bases of the second and following gastric segments are broader, darker, and more sharply marked off from the remainder of the segments. The green portions of the typical longinoda female are slightly more olivaceous and less pea-green, and the basal bands of the gaster are more exposed and brownish; the appendages are more brownish.

The male longinoda is scarcely smaller than that of smaragdina , and measures 6 to 6.5 mm., but the head, thorax, and petiole are darker and more blackish; the head is decidedly broader, especially behind, the mandibles, petiole, antennal scapes, and wings are decidedly shorter and the integument is less shining.

The workers of the various subspecies and varieties of the two species may be separated by means of the following key.

1. Petiole very slender, its stigmata seen from above very prominent, its ventral surface nearly straight or very feebly convex in profile ( smaragdina )....2.

Petiole stouter and higher, its stigmata seen from above not prominent, its ventral surface strongly convex in profile ( longinoda )..................7.

2. Body ferruginous or testaceous.........................................3.

Gaster and sometimes the head pea-green, head more rounded and less truncated behind; size smaller, petiole somewhat shorter (Queensland, New Guinea, Islands Aru and Key).................subspecies virescens (Fabricius) .

3. Integument opaque or subopaque.......................................4.

Integument more or less distinctly shining..............................5.

4. Color ferruginous (India, Ceylon, Cochin China, Indonesia). smaragdina (typical).

Smaller and more testaceous, mesonotum and petiole a little narrower (Java). variety gracilior Forel.

5. Large forms, integument slightly shining (Papua, Philippines, Melanesia). subspecies subnitida Emery. Smaller forms, integument more shining................................6.

6. Body very shining and slender, color testaceous, head rather elongate (Island of Batjan)..................................... variety gracillima Emery.

Less shining and less slender, head shorter (Celebes). variety selebensis Emery.

7. Ferruginous or testaceous throughout...................................8.

Brown or black........................................................9.

8. Color ferruginous (West Africa)........................ longinoda (typical).

Color paler, more testaceous, petiole shorter, head slightly broader, apical tooth

of mandibles shorter (Zanzibar)............... variety textor (Santschi). 9. At least the thorax and mandibles black................................10.

Body rather uniformly brown (Belgian Congo). variety annectens , new variety.

10. Head dull red, gaster often brownish (Belgian Congo).. variety rubriceps (Forel).

Head and gaster black or dark brown (Belgian Congo, Nigeria, Liberia, Cameroon, Spanish Guinea)................... variety fusca (Emery).

Oe. fusca was originally described by Emery as an independent species, but Forel reduced it to subspecific rank on finding the variety rubriceps , which shows some color variation in the direction of the typical longinoda . The discovery of another variety, annectens described below, connecting rubriceps and longinoda is additional evidence that fusca cannot be maintained as a species. In my opinion it is merely an extreme melanic variety, for I am unable to detect in it any morphological characters of even subspecific value. All of the varieties of longinoda are equally polymorphic in the worker caste and the smallest individuals all agree with the description of Andre's brevinodis , except in color.

The ethological observations of Chun1 and Father Kohl2 refer to this species.

Mr. Lang's photographs reproduced on Pl. XX, figs. 1 and 2, show two of the nests of the typical longinoda from Malela, consisting of the leaflets of a bush skillfully folded and united with the white silk spun by the young larvae. He found that the nests of longinoda and its varieties are most often constructed on bushes and are sometimes only a few feet from the ground. Text Fig. 59 shows a nest of this ant placed in a coffee tree at Avakubi. The habits seem to be the same in all essential particulars as those of smaragdina .