Megalomyrmex iheringi

Brandão (1990) - At the Estacao Biologica de Boraceia I collected, under a rotten log, a colony with 260 workers, immatures (only larvae) and a dealated queen. The colony occupied hollow spaces among crevices and the soil beneath. I was not able to observe any definite entrances. Uiderwaldt (1926) described the nest of M. iheringi as: “found in the wild, among bromeliads and epiphytes, with approximately 200 workers”.

Identification
Brandão (1990) - The medium seta of the clypeus may be wanting in some workers. Also the antennal sockets may be circled by a faint striation, which can reach the lateral portions of the clypeus.

Distribution
M. iheringi is known only from localities above 800m at Serra do Mar, in the vicinity of the city of Sao Paulo.

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil.

Biology
Brandão (2003) - The Estação Biológica de Boracéia, from where most of the few known samples of M. iheringi came from, is located some 70 Km in straight line from Ilha de São Sebastião. This island is separated from the mainland by the relatively narrow São Sebastião Channel (less than 2 Km in the narrower width), and it is covered by vegetation which is very similar to that of the Serra do Mar. In my 1990 revision, I listed a worker of Megalomyrmex goeldii from Boracéia, although a re-examination of this individual led me to re-identify it as a very small M. iheringi. This raises doubts on the identity of M. iheringi, as I used overall size as the main diagnostic character between them. This was also the only locality where sympatry was ever recorded among these two species. It seems premature to consider them conspecific given that the two species consistently differ in the length of the trunk.

I also studied a worker ( collection # 143) from Parque Estadual Carlos Botelho, São Paulo state, Brazil (24°00’-20’S, 47°44’-48’W) collected with “Taz” (sic) bait by Y.M.B. Neptume in January 13, 1991. This collection was made probably around the headquarters of the Park. The latter covers parts of Eldorado Paulista, Sete Barras, Tapirai and São Miguel Arcanjo counties. This is an additional record of M. iheringi with consistently larger measurements of Weber’s length of thunk than in any M. goeldii.

Recently, Tavares (2002) collected a worker of M. iheringi at 750 m of altitude from sea level in Base Barra Grande, Parque Estadual Intervales (24°17’02”S, 47°45’20’30”W), São Paulo state, Brazil, syntopic with M. goeldii, also from 1 m2 litter samples subjected to Winkler extractor. This is the southernmost record for this species.

Nomenclature

 *  iheringi. Megalomyrmex iheringi Forel, 1911c: 304 (w.) BRAZIL. Borgmeier, 1930: 33 (q.). See also: Brandão, 1990: 424.

Worker
Brandão (1990) - Mandibles smooth; clypeus not carinate, with anterior margin round, not denticulate; frontal suture not impressed: club with 3 segments; occipital margin raised but not visible in frontal view; dorsal pronotal profile continuous: promesonotal suture impressed dorsally; mesosternum and metasternum without ventral processes: dorsal face and declivity of propodeum meeting laterally in an obtuse angle, dorsal face faintly impressed medially; declivity without rugosities: ventral face of petiole with anterior denticle; postpetiole without ventral process.

Pilosity: small suberect hairs (ca .1 mm) uniformly covering antennae, head capsule, mandibles, legs, anterior face of petiole and postpetiole nodes and gaster. Long hairs (ca. .2mm) at thorax dorsum and apex of petiole and postpetiole nodes.

Color: uniformly bright reddish-brown.

Borgmeier (1930) pointed out some inaccuracies in Forel's original description, especially as to the raised margin of vertex. Furthermore, I observed in all studied workers an anterior denticle on the ventral face of the petiole, contrary to Forel's statements.

Type Material
Parque Cajuru, Alto da Serra (municipio de Paranapiacaba), SP, Brasil (23°47'S, 46°19'W). Borgmeier, 1930: 33-34, est. 5, figs. 29-32, queen. Lectotype designation: Lectotype (Alto da Serra) and 14 paralectotypes (10 from Alto da Serra and 4 from Parque Cajuru) at Museu de Zoologia da USP; 1 paralectotype (Alto da Serra) at Museu Nacional do Rio de Janeiro: 3 paralectotypes (Alto da Serra) at Museum de Ia Ville de Geneve.

The female caste has been described by Borgmeier (op. cit.) from a dealated queen, possibly collected with the syntype workers. and labelled as a “cotype”. As Forel explicitly used only the worker and may have not even studied this particular female I added a label to the queen saying “nao consta da descricao original, Brandao, 1985”. All known queens of this species are dealated. Borgmeier's specimen has the largest ocelli in the series.