The solidus species group

(Fig. 52)

The solidus group is monotypic. Its unique species was described by Kempf (1974) as Zacryptocerus solidus, within the angustus group. The angustus and solidus groups share the dorsal and declivous faces of propodeum continuous, not meeting in a distinct propodeal angle, but differ by the mesonotum and propodeum unarmed in solidus, while in angustus there is a pair of denticles on the mesonotum and a series of denticles on propodeum.

In the morphological phylogeny by De Andrade and Baroni Urbani (1999, see their Fig. 24), C.solidus isnot related with theangustus group species, being more closelyrelated to the pusillus group. Nevertheless, most of the characters used in their morphological analysis are based on soldiers. However, C. solidus is a rarely collected species, with only five workers known so far from northern Brazil (Fig. 52). This species was not included in the molecular phylogeny (Price et al., 2016).

Diagnosis: Dorsal and declivous faces of propodeum continuous, not meeting in a distinct propodeal angle. Metanotum and propodeum unarmed (Fig. 2e).

Brazilian species of solidus group

Cephalotes solidus (Kempf, 1974)

Obsolete combination: Zacryptocerus solidus