Rogeria germaini

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Rogeria germaini
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Solenopsidini
Genus: Rogeria
Species: R. germaini
Binomial name
Rogeria germaini
Emery, 1894

Rogeria germaini casent0178168 profile 1.jpg

Rogeria germaini casent0178168 dorsal 1.jpg

Specimen labels

Synonyms

Most specimens have come from Winkler apparatus collecting by expeditions from the MHNG in Geneva. Specimens were extracted from rotting leaf litter and wood in forests.

Identification

Kugler (1994) - germaini species group. WL 0.74-0.90mm. Clypeal apron with median tooth. Metanotal groove very weak or absent. Metapleural lobes reduced, not angular. Petiolar keel not lamellate. Sting shaft apex weak, lacks dorsal flange; lancets spatulate. Macrosculpture effaced on side of head below eye; sometimes nearly smooth. Promesonotal rugae sharp and narrow like those on head; rugae low on sides of pronotum do not continue onto metanotum. Macrosculpture on both nodes and petiolar peduncle vestigial. Scapes without erect hair. Mesosoma with erect-suberect only. Head and gaster with both erect and decumbent pilosity.

Rogeria lirata from more northern parts of South America is the closest relative. Rogeria lacertosa, also from southern Brazil, differs in size, clypeal shape, sculpture on side of head, and pilosity. Rogeria pellecta, collected further south in Brazil, differs in clypeal shape, meta pleural lobes, sting, and pilosity.

Keys including this Species

Distribution

Southern Brazil and Paraguay

Distribution based on Regional Taxon Lists

Neotropical Region: Brazil (type locality), Paraguay.

Distribution based on AntMaps

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Distribution based on AntWeb specimens

Check data from AntWeb

Biology

The following is modified from Kugler (1994): Little is known about these cryptic ants. Collection records typically range from sea level to 1000m, but five species extend higher and two (Rogeria unguispina and Rogeria merenbergiana) can be found at 2000m. Rogeria are generally collected in moist forests (primary or secondary forests, coffee or cacao plantations), but at higher elevations can be found in pastures (Rogeria leptonana, Rogeria merenbergiana). Several species (Rogeria creightoni, Rogeria cuneola, Rogeria foreli) have been found in moist and dry climates. Rogeria foreli is the most unusual, with some members dwelling at over 1800m in the temperate mountains of southern Arizona.

Most species have only been collected as strays or by Berlese or Winkler sampling, from leaf litter and rotten wood, but occasionally among epiphytes and moss (Rogeria belti, creightoni, Rogeria exsulans). Nests of several species (belti, Rogeria blanda, merenbergiana) have been found under the loose bark of rotten logs. Nests of blanda and Rogeria tonduzi have been taken from the trunks of cacao trees. A nest of Rogeria leptonana was found at 1750m under a rock in a pasture.

Nests are rarely found. Males are known for only four species (belti, blanda, leptonana and Rogeria stigmatica) and queens associated through nest series for only nine species.

Castes

Males have not been collected.

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • germaini. Rogeria germaini Emery, 1894c: 189 (w.) BRAZIL. Kugler, C. 1994: 42 (q.). See also: Kempf, 1962b: 20. Senior synonym of minensis: Kugler, C. 1994: 42.
  • minensis. Rogeria germaini st. minensis Santschi, 1923g: 1262 (w.) BRAZIL. Raised to species: Kempf, 1963a: 189. Junior synonym of germaini: Kugler, C. 1994: 42.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Kugler (1994) - Kempf (1963) examined the types of germaini and minensis and noted that they were very similar, but chose to retain both names on the basis of a list of differences he saw in those specimens. I have also examined the types as well as 11 specimens collected in Paraguay in 1979 and 1982. These new collections bridge the gap between the types of germaini and minensis. They are all intermediate in size between the smaller germaini type and the larger minensis types, have convex posterior heads like the germaini type, have promesonotal sculpture varying from nearly as extensively rugose as the germaini type, to areolate like the minensis types; and some have petiolar nodes intermediate between the more abruptly arising minensis-like and the more obliquely arising germaini-like nodes.

Description

Worker

Kugler (1994) - TL 2.7-3.5, HL 0.66-0.85, HW 0.59-0.74, SL 0.45-0.59, EL 0.06-0.10 (7-13 facets), PW 0.44-0.51, WL 0.74-0.90, SpL 0.15-0.21, PetL 0.30-0.44, PpetL 0.19-0.23mm, CI 0.86-0.89, OI 0.09-0.14, 51 0.75-0.80, PSI 0.20-0.23. N=9

Kugler 1994 fig 24-31

Additions to Kempf (1962b). Dentition variable; simplest pattern is 6 teeth of decreasing size, however, it seems that any or all of the last 3 teeth may be replaced by a pair of denticles. FLW / HW 0.32-0.36. Posterior outline of head concave to convex. Anterior propodeum marked by a transverse carina. Petiolar node distinct; Figs. 24 and 26 show extremes of shape. Postpetiolar node with a distinct posterior face; shape from above as in Figs. 24 or 32. Sting apparatus differing dramatically from that of inermis in some features: 1) sting shaft and lancets very weak, 2) lancets spatulate as in Fig. 29, 3) sting shaft apex with eroded sides, and no dorsal flange, and 4) furcula with a shorter dorsal arm that broadly merges with the lateral arms, thus appearing broadly V-shaped in anterior view.

Posterior head transversely arching rugose to rugose-areolate. Promesonotal dorsum varies from predominantly areolate (with occasional elongate cells) to predominantly vermiculate-rugose. Pronotal sides rugose; rugae subparallel with ventral edge of pronotum to diagonal. Microsculpture vestigial, leaving irregular, but shiny spaces in macrosculpture; sides of mesosoma especially smooth.

Color brownish-yellow to brown with darker gaster; appendages at times slightly lighter.

Queen

Kugler (1994) - TL 4.1, HL 0.90, HW 0.79, SL 0.73 EL 0.17, PW 0.67, WL 1. 12, SpL 0.15, PetL 0.48, PpetL 0.28mm, CI 0.88, 51 0.92, PSI 0.13. N=l

Differing from the worker in the normal queen characteristics and the following. Notch formed by nuchal groove not so distinct in lateral view. Anteroventral corner of pronotum not as dearly dentate. Parapsidal furrows not distinguishable from furrows in sculpture. Diverging rugae on middorsum of head continue onto posterior head, with few or no lateral spurs. Laterodorsa and sides of head similarly rugose. Anterior face of pronotum transversely areolate, mesonotum with longitudinal rugae diverging from an anterior point, then parallel in posterior half; some branching, but no cross-ridges; less vermiculate than in worker.

Type Material

Kugler (1994) :

Syntype workers, BRAZIL: Mato Grosso (Germain) Museo Civico di Storia Naturale, Genoa [1 of 2 syntypes examined].

Rogeria germaini minensis Lectotype and paratype workers, BRAZIL: Minas Gerais, Passa Quatro (Reichensperger) Naturhistorisches Museum Basel [Both lectotype and paratype examined].

References

  • Emery, C. 1894d. Studi sulle formiche della fauna neotropica. VI-XVI. Bull. Soc. Entomol. Ital. 26: 137-241 (page 189, worker described)
  • Kempf, W. W. 1962b. Miscellaneous studies on neotropical ants. II. (Hymenoptera, Formicidae). Stud. Entomol. 5: 1-38 (page 20, see also)
  • Kugler, C. 1994. A revision of the ant genus Rogeria with description of the sting apparatus (Hymenoptera: Formicidae). J. Hym. Res. 3: 17-89 (page 42, Senior synonym of minensis)