Mycetophylax lectus

This species is only known from two collections.

Identification
See the description below.

Distribution
Aside from the type series, this species has also been recorded by Santschi (1925: 164) from Fives Lille, in Santa Fé Province, Argentina. I have not seen these specimens (Kempf 1964).

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina, Brazil, Paraguay.

Biology
Kempf (1964) - According to Luederwaldt (1926: 267) the nest of this species was found in an open field (same habitat as Mycocepurus goeldii). The cavities were subspherical. The fungus garden is sessile.

Ramos-Lacau et al. 2015 (abstract): Cyphomyrmex ants are a basal group of small fungus-growers (Myrmicinae:Attini), which differ profoundly from their most studied relatives Atta and Acromyrmex. Our objective was to investigate the nest biology and demography of the fungus-growing ant Cyphomyrmex lectus in a transitional area (savanna-forest) disturbed by an annual fire regime, in Southeast Brazil. The colonies of C. lectus were located close to each other (mean distance between nests, 3.38 ± 2.75 m). Its external nest structure consisted of a single circular nest-entrance hole but without a conspicuous nest mound. Nests were relatively simple consisting of a single well-formed chamber and a single gallery connecting to the nest entrance. No relationships were found between ant number per colony and gallery length, as well as chamber volume. Nonetheless, we detected an effect of the ant number per colony on chamber depth. In this sense, a deeper chamber could warrant a better protection against fire, natural enemies and offer favorable micro-conditions to yeast culture. The colonies of C. lectus are small (a mean of 70 ± 49.4 individuals/colony). Alates, larvae and pupae were found only in one out of eight colonies. A single dealate queen per colony was observed strongly suggesting that this species is monogynous. Further studies could evaluate whether (1) nests density differ before and after fire periods, (2) fire occurrence affects the survival and establishment rate of new colonies, as well as (3) the nest microclimatic conditions necessary to yeast culture.

Castes
Queen and male are unknown.

Nomenclature

 *  lectus. Atta (Cyphomyrmex) olitrix subsp. lecta Forel, 1911c: 295 (w.) BRAZIL. Combination in Cyphomyrmex: Luederwaldt, 1918: 39. Raised to species: Kempf, 1964d: 36.

Description
Kempf (1964) - The broadly expanded frontal carinae, the foliaceous carina on postero-inferior corner of head, the huge inferior pronotal spine, the unarmed epinotum, vouch for specific distinction from Cyphomyrmex olitor. The species seems more closely related with Cyphomyrmex nemei and perhaps Cyphomyrmex vallensis.

Worker
Kempf (1964) - (lectotype and paratypes). - Total length 2.7-2.8 mm; head length 0.64-0.67 mm; head width 0.59-0.61 mm; thorax length 0.80-0.83 mm; hind femur length 0.59-0.61 mm. Yellowish brown; front of head ferruginous; legs rather pale.

Head (fig 12). Mandibles finely reticulate-punctate and vestigially striolate; chewing border with 7 teeth; apical tooth prominent. Anterior clypeal border slightly notched in the middle, laterally with a small tooth. Frontal area more or less distinct and impressed. Frontal lobes greatly expanded laterad, covering in full-face view part of the eyes, anteriorly rounded, then diverging caudad and somewhat sinuous, rounded behind before the gentle constriction; frontal carinae prolonged caudad, slightly diverging, joining the narrowly crested preocular carina to close the antennal scrobe at the scarcely drawn-out occipital corner. Occiput broadly but gently emarginate, with another median and deeper emargination between the short and inconspicuous carinae of the vertex. Supraocular tumulus feeble and indistinct. Inferior border of cheeks immarginate, except for a short and low foliaceous carina in front of the inferior occipital corner. Scapes in repose not surpassing the occipital corner. Funicular segments II-VIII not longer than broad.

Thorax (fig 14). Midpronotal tooth feeble and indistinct, lateral teeth low and subconical, antero-inferior corner with a very long tooth pointing foreward. Mesonotum flat to slightly excavate, flanked by the anterior and posterior pair of very low tubercles, which clearly separate the dorsum from the sides. Mesoepinotal suture distinct, but only gently impressed. Basal face of epinotum much shorter than the laterally immarginate declivous face, posteriorly unarmed. Inferior borders of femora faintly crested; hind femora gradually increasing in depth toward basal third, forming ventrally an angle, the postero-inferior border being armed at this place with a prominent foliaceous flange.

Pedicel (fig 14). Note the narrow postero-median laminule flanked by short longitudinal carinules. Postpetiole cupuliform, dorsally flattened; lateral lobes with foliaceous margin, not appressed. Tergum I of gaster with marginate anterior border, laterally immarginate, mesially not impressed.

Integument densely granulate, opaque, with sparser small setigerous pits. Hairs minute, completely appressed. Gular face of head and sternum I of gaster with curved subdecumbent hairs.

Type Material
Kempf (1964) - 14 workers taken by H. Luederwaldt in the borough of lpiranga in São Paulo City, in 1909 (MHNG, DZSP, WWK).