Meranoplus mayri

Boudinot, B. E. & B. L. Fisher, 2013, A taxonomic revision of the Meranoplus F. Smith of Madagascar (Hymenoptera: Formicidae: Myrmicinae) with keys to species and diagnosis of the males., Zootaxa 3635 (4), pp. 301-339 : 311-312

Diagnosis of the M. mayri species group (worker)

The Meranoplus mayri group consists of M. mayri , from Madagascar, and M. levis Donisthorpe, 1942 , from South India and Sri Lanka. This group was proposed by Schödl (1998) based on the arcing costate sculpture of the promesonotal shield and longitudinal costate sculpture of the head. On the basis of examination of the M. levis holotype and the morphometrics provided by Schödl (1998), we concur and provide additional characters in the M. mayri species group diagnosis. Diangosis of the sexuals of this species group would be premature, however, as gynes and males of M. levis are unknown.

The following characters set the species of the M. mayri group apart among the Afrotropical species-group schemata of Bolton (1981) and the Oriential species from Schödl (1998, 1999); unique character states for the M. mayri group among the Afrotropical and Oriental species are italicized:

1. Bicolored: head through postpetiole dark to bright orange, abdominal segments IV–VII piceous to black.

2. Face with longitudinal costae.

3. Frontal carina laminate and broadly translucent, at least until midlength of eye.

4. Head broader than long (CI> 100).

5. Dorsum of promesonotal shield with numerous concentric costae arcing anteriorly from one posterolateral spine to the other.

6. Lateral and posterior margins of promesonotal shield distinctly laminate and concealing pleurae and propodeum in dorsal view.

7. Lateral margins of promesonotal shield translucent from anterolateral corners to bases of posterolateral spines.

8. Posterolateral promesonotal spines somewhat dorsoventrally flattened, with one or two ventrolateral longitudinal carinae.

9. Petiolar apex acute in profile view.

10. Petiole anterior and posterior faces smooth.

11. Lateral face of petiole with one to many longitudinal costae or carinae.

12. Petiole dorsal margin straight to convex in posterior view; without spines or teeth near mid-line.

13. Postpetiole nodiform, strongly sculptured.

14. External (dorsal) tibial faces roughened with sculpture.

15. Fourth abdominal tergum dense-punctate, at least posteriorly.