Strumigenys

Hita Garcia, Wiesel and Fischer (2013) - A species-rich, worldwide occurring genus mainly distributed in the world tropics and subtropics (Bolton, 2000). The current genus definition includes the former genus Pyramica, which was proposed as junior synonym some years ago (Baroni Urbani and De Andrade, 2007). The taxonomy of the whole tribe was exhaustively revised by Bolton (2000) on a global scale. Most Strumigenys species are small, cryptic ants that nest and forage in leaf litter, in soil, or in rotten wood, whereas there are far fewer genus members that prefer an arboreal life-style. Many species are specialised predators possessing trap-jaw mandibles, and mainly hunt collembolans or other small arthropods (Hölldobler & Wilson, 1990; Bolton, 1999).

Identification
Strumigenys species groups
 * Species Groups

Biology
Keiichi Masuko and Alain Dejean have published various papers on predatory behaviour in this genus

Nomenclature

 *  STRUMIGENYS [Myrmicinae: Dacetini]
 * Strumigenys Smith, F. 1860c: 72. Type-species: Strumigenys mandibularis, by monotypy.
 * Strumigenys senior synonym of Labidogenys: Roger, 1863b: 40; Brown & Wilson, 1959b: 281; Brown, 1960b: 37.
 * Strumigenys senior synonym of Eneria, Proscopomyrmex: Brown, 1949d: 15.
 * Strumigenys senior synonym of Quadristruma: Baroni Urbani & De Andrade, 1994: 12; Bolton, 1999: 1673.
 * Strumigenys senior synonym of: Asketogenys, Borgmeierita, Cephaloxys, Chelystruma, Cladarogenys, Codiomyrmex, Codioxenus, Dorisidris, Dysedrognathus, Epitritus, Glamyromyrmex, Gymnomyrmex, Kyidris, Miccostruma, Neostruma, Pentastruma, Platystruma, Polyhomoa, Pyramica, Serrastruma, Smithistruma, Tingimyrmex, Trichoscapa, Weberistruma, Wessonistruma: Baroni Urbani & De Andrade, 2007: 101.
 * ASKETOGENYS [junior synonym of Pyramica]
 * Asketogenys Brown, 1972: 23. Type-species: Asketogenys acubecca, by original designation.
 * Asketogenys junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Asketogenys junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 15; Baroni Urbani & De Andrade, 2007: 103.
 * BORGMEIERITA [junior synonym of Pyramica]
 * Borgmeierita Brown, 1953g: 23. Type-species: Codiomyrmex excisus, by original designation.
 * Borgmeierita junior synonym of Glamyromyrmex: Brown, 1973a: 35.
 * Borgmeierita junior synonym of Strumigenys: Baroni Urbani & De Andrade, 2007: 103.
 * Borgmeierita junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * CEPHALOXYS [junior homonym, see Smithistruma]
 * Cephaloxys Smith, F. 1865: 76. Type-species: Cephaloxys capitata, by monotypy. [Junior homonym of Cephaloxys Signoret, 1847: 294 (Hemiptera).]
 * Smithistruma Brown, 1948e: 104, replacement name for Cephaloxys Smith.
 * CHELYSTRUMA [junior synonym of Pyramica]
 * Chelystruma Brown, 1950a: 33 [as subgenus of Glamyromyrmex]. Type-species: Glamyromyrmex (Chelystruma) lilloana, by monotypy.
 * Chelystruma raised to genus: Kempf, 1959d: 338.
 * Chelystruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Chelystruma junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 103.
 * CLADAROGENYS [junior synonym of Pyramica]
 * Cladarogenys Brown, 1976b: 33. Type-species: Cladarogenys lasia, by original designation.
 * Cladarogenys junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Cladarogenys junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 103.
 * CODIOMYRMEX [junior synonym of Pyramica]
 * Codiomyrmex Wheeler, W.M. 1916d: 326. Type-species: Codiomyrmex thaxteri, by monotypy.
 * Codiomyrmex subgenus of Strumigenys: Emery, 1924d: 325.
 * Codiomyrmex revived status as genus: Wheeler, W.M. 1916d: 326; Brown, 1948e: 114.
 * Codiomyrmex junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Codiomyrmex junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 101.
 * CODIOXENUS [junior synonym of Pyramica]
 * Codioxenus Santschi, 1931c: 278 [as subgenus of Epitritus]. Type-species: Epitritus (Codioxenus) simulans, by monotypy.
 * Codioxenus raised to genus: Brown, 1948e: 123.
 * Codioxenus junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Codioxenus junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 101.
 * DORISIDRIS [junior synonym of Pyramica]
 * Dorisidris Brown, 1948e: 116. Type-species: Strumigenys (Codiomyrmex) nitens, by original designation.
 * Dorisidris junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Dorisidris junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 102.
 * DYSEDROGNATHUS [junior synonym of Pyramica]
 * Dysedrognathus Taylor, 1968c: 132. Type-species: Dysedrognathus extemenus, by original designation.
 * Dysedrognathus junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Dysedrognathus junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 13; Baroni Urbani & De Andrade, 2007: 103.
 * ENERIA [junior synonym of Strumigenys]
 * Eneria Donisthorpe, 1948d: 598. Type-species: Eneria excisa (junior synonym of Strumigenys loriae), by original designation.
 * Eneria junior synonym of Strumigenys: Brown, 1949d: 15.
 * EPITRITUS [junior synonym of Pyramica]
 * Epitritus Emery, 1869a: 136. Type-species: Epitritus argiolus, by monotypy.
 * Epitritus junior synonym of Pyramica: Bolton, 1999: 1667; Bolton, 2000: 90.
 * Epitritus junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 12; Baroni Urbani & De Andrade, 2007: 101.
 * GLAMYROMYRMEX [junior synonym of Pyramica]
 * Glamyromyrmex Wheeler, W.M. 1915e: 487. Type-species: Glamyromyrmex beebei, by monotypy.
 * Glamyromyrmex senior synonym of Borgmeierita: Brown, 1973a: 35.
 * Glamyromyrmex junior synonym of Pyramica: Bolton, 1999: 1667; Bolton, 2000: 91.
 * Glamyromyrmex junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 101.
 * GYMNOMYRMEX [junior synonym of Pyramica]
 * Gymnomyrmex Borgmeier, 1954b: 279. Type-species: Gymnomyrmex splendens, by original designation.
 * Gymnomyrmex junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Gymnomyrmex junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 103.
 * KYIDRIS [junior synonym of Pyramica]
 * Kyidris Brown, 1949d: 3. Type-species: Kyidris mutica, by original designation.
 * Kyidris senior synonym of Polyhomoa: Creighton, 1950b: 93; Brown & Yasumatsu, 1951: 93.
 * Kyidris junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Kyidris junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 15; Baroni Urbani & De Andrade, 2007: 103.
 * LABIDOGENYS [junior synonym of Strumigenys]
 * Labidogenys Roger, 1862a: 249. Type-species: Labidogenys lyroessa, by monotypy.
 * Labidogenys junior synonym of Strumigenys: Roger, 1863b: 40.
 * Labidogenys revived from synonymy: Brown, 1948e: 102.
 * Labidogenys junior synonym of Strumigenys: Brown & Wilson, 1959b: 281; Brown, 1960b: 38.
 * MICCOSTRUMA [junior synonym of Pyramica]
 * Miccostruma Brown, 1948e: 123. Type-species: Epitritus mandibularis, by original designation.
 * Miccostruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Miccostruma junior synonym of Smithistruma: Bolton, 1983: 274.
 * NEOSTRUMA [junior synonym of Pyramica]
 * Neostruma Brown, 1948e: 111. Type-species: Strumigenys crassicornis, by original designation.
 * Neostruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Neostruma junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 12; Baroni Urbani & De Andrade, 2007: 102.
 * PENTASTRUMA [junior synonym of Pyramica]
 * Pentastruma Forel, 1912a: 50. Type-species: Pentastruma sauteri, by monotypy.
 * Pentastruma junior synonym of Pyramica: Bolton, 1999: 1667; Bolton, 2000: 91.
 * Pentastruma junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 15; Baroni Urbani & De Andrade, 2007: 101.
 * PLATYSTRUMA [junior synonym of Pyramica]
 * Platystruma Brown, 1953g: 112 [as subgenus of Smithistruma]. Type-species: Strumigenys (Cephaloxys) depressiceps, by original designation.
 * Platystruma junior synonym of Smithistruma: Brown, 1973a: 35.
 * Platystruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * POLYHOMOA [junior synonym of Pyramica]
 * Polyhomoa Azuma, 1950: 36. Type-species: Polyhomoa itoi (junior synonym of Kyidris mutica), by monotypy.
 * Polyhomoa junior synonym of Kyidris: Creighton, 1950b: 93; Brown & Yasumatsu, 1951: 93.
 * Polyhomoa junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * PROSCOPOMYRMEX [junior synonym of Strumigenys]
 * Proscopomyrmex Patrizi, 1946: 294. Type-species: Proscopomyrmex londianensis, by monotypy.
 * Proscopomyrmex junior synonym of Strumigenys: Brown, 1949d: 15; Bolton, 1999: 1673.
 * PYRAMICA [Myrmicinae: Dacetini]
 * Pyramica Roger, 1862a: 251. Type-species: Pyramica gundlachi, by monotypy.
 * Pyramica junior synonym of Strumigenys: Roger, 1863b: 40.
 * Pyramica revived from synonymy as subgenus of Strumigenys: Brown, 1948e: 110.
 * Pyramica senior synonym of: Asketogenys, Borgmeierita, Cephaloxys, Chelystruma, Cladarogenys, Codiomyrmex, Codioxenus, Dorisidris, Dysedrognathus, Epitritus, Glamyromyrmex, Gymnomyrmex, Kyidris, Miccostruma, Neostruma, Pentastruma, Platystruma, Polyhomoa, Serrastruma, Smithistruma, Tingimyrmex, Trichoscapa, Weberistruma, Wessonistruma: Bolton, 1999: 1667; Bolton, 2000: 90.
 * Pyramica junior synonym of Strumigenys: Brown & Wilson, 1959b: 281; Brown, 1960b: 37; Baroni Urbani & De Andrade, 2007: 101.
 * QUADRISTRUMA [junior synonym of Strumigenys]
 * Quadristruma Brown, 1949b: 47. Type-species: Epitritus emmae, by original designation.
 * Quadristruma junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 12; Bolton, 1999: 1673; Bolton, 2000: 492.
 * SERRASTRUMA [junior synonym of Pyramica]
 * Serrastruma Brown, 1948e: 107 [as subgenus of Smithistruma]. Type-species: Strumigenys simoni, by original designation.
 * Serrastruma raised to genus: Brown, 1949d: 6.
 * Serrastruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Serrastruma junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 102.
 * SMITHISTRUMA [junior synonym of Pyramica]
 * Smithistruma Brown, 1948e: 104. Replacement name for Cephaloxys Smith, F. 1865: 76. [Junior homonym of Cephaloxys Signoret, 1847: 294 (Hemiptera).]
 * [Type-species not Strumigenys pulchella, unjustified subsequent designation by Brown, 1948e: 104, repeated in Kempf, 1972a: 230, Bolton, 1983: 274 and Bolton, 1995b: 46.]
 * Smithistruma senior synonym of Platystruma, Weberistruma, Wessonistruma: Brown, 1973a: 35.
 * Smithistruma senior synonym of Miccostruma: Bolton, 1983: 274.
 * Smithistruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Smithistruma junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 14; Baroni Urbani & De Andrade, 2007: 102.
 * TINGIMYRMEX [junior synonym of Pyramica]
 * Tingimyrmex Mann, 1926: 104 [as subgenus of Strumigenys]. Type-species: Strumigenys (Tingimyrmex) mirabilis, by monotypy.
 * Tingimyrmex raised to genus: Brown, 1948e: 111.
 * Tingimyrmex junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.
 * Tingimyrmex junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 15; Baroni Urbani & De Andrade, 2007: 101.
 * TRICHOSCAPA [junior synonym of Pyramica]
 * Trichoscapa Emery, 1869b: 24 [as subgenus of Strumigenys]. Type-species: Strumigenys (Trichoscapa) membranifera, by monotypy.
 * Trichoscapa junior synonym of Strumigenys: Dalla Torre, 1893: 145.
 * Trichoscapa junior synonym of Cephaloxys: Wheeler, W.M. 1922a: 668; Emery, 1924d: 323.
 * Trichoscapa revived from synonymy: Brown, 1948e: 112.
 * Trichoscapa subgenus of Strumigenys: Creighton, 1950a: 304.
 * Trichoscapa status as genus: Kempf, 1972a: 255; Bolton, 1983: 319.
 * Trichoscapa junior synonym of Pyramica: Bolton, 1999: 1667; Bolton, 2000: 90.
 * Trichoscapa junior synonym of Strumigenys: Baroni Urbani & De Andrade, 1994: 13; Baroni Urbani & De Andrade, 2007: 101.
 * WEBERISTRUMA [junior synonym of Pyramica]
 * Weberistruma Brown, 1948e: 106 [as subgenus of Smithistruma]. Type-species: Strumigenys (Cephaloxys) leptothrix, by original designation.
 * Weberistruma raised to genus: Brown, 1949d: 7.
 * Weberistruma junior synonym of Smithistruma: Brown, 1973a: 35.
 * Weberistruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91].
 * WESSONISTRUMA [junior synonym of Pyramica]
 * Wessonistruma Brown, 1948e: 106 [as subgenus of Smithistruma]. Type-species: Strumigenys pergandei, by original designation.
 * Wessonistruma junior synonym of Smithistruma: Brown, 1973a: 35.
 * Wessonistruma junior synonym of Pyramica: Bolton, 1999: 1668; Bolton, 2000: 91.

Baroni Urbani & De Andrade (2007) - In our study this genus results characterized by the following synapomorphies:

Worker (and gyne) reduction of the labial palps from 2 to 1. CI 0.70, RI 0.67. This trait is shared also with Acanthognathus and with some Basiceros species previously included in Talaridris.

Worker (and gyne) presence of a basi mandibular process. CI 0.67, RI 0.86. The synapomorphic state of this character (sometimes of doubtful detection, see Fig. 10) is an artefact of character optimization due to the fact that the basi mandibular process is absent in Phalacromyrmex, Pilotrochus, Ishakidris, Basiceros, and the hypothetical ancestor of Acanthognathus (process present in highly transformed form) and the remaining Dacetini genera (process present). Because of its widespread presence in a number of Dacetini genera, presence of the basimandibular process is a poor discriminant trait to identify Strumigenys.

Worker (and gyne) mesosternal hair beds visible in profile. CT 0.91, RI 0.67. In spite of its perfect match within Strumigenys, this character is irregularly distributed among several dacetine genera including the three monotypic genera Phalacromyrmex, Pilotrochus and Ishakidris. Moreover, we regard the character itself as insecure: mesosternal hair beds are widespread and coding their visibility in profile as phylogenetically significant needs some imagination and abstraction capacity.

Worker (and gyne) eyes ventral. CI 0.67, RI 0.80. This trait is shared with all and only the former Phalacromyrmecini, but was coded as polymorphic in “Pyramica” as a result of our transfer to Strumigenys of the blind species inopinata (see below, the list of new combinations in Strumigenys) originally described in “Rhopalothrix”. The position of the eyes, otherwise, is likely to represent the main synypomorphy of the genus.

Gyne (and male?) secondary loss of the anal vein. CI 0.75, RI 0.50. This trait appears to be constant among Strumigenys but it reappears in some Acanthognathus and Basiceros species.

Strumigenys (including Pyramica) results weakly defined from our analysis, unable to focus on one single clear-cut synapomorphy. On the other hand, by appearing as branch in a tetratomy, its sister-group with which it could eventually be merged is also not clearly identified. For these reasons and for nomenclatorial conservationism we prefer to provisionally maintain Strumigenys as a valid genus defined by a combination of characters, a procedure seldom accepted in phylogenetic studies.