Neivamyrmex

Neivamyrmex; Temporal range: 20.43–0 Ma K Pa Eo Ol Mi Pl Early Miocene – Recent
	Neivamyrmex nigrescens
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Dorylinae
Genus:	Neivamyrmex; Borgmeier, 1940
Type species
	Eciton schmitti (junior synonym of Neivamyrmex nigrescens);
Diversity
	129 species; 1 fossil species; (Species Checklist, Species by Country) Neivamyrmex nigrescens Specimen Label
Synonyms
	Acamatus Emery, 1894; Woitkowskia Enzmann, E.V., 1952;

Army ants that prey on ants and termites. Subterranean in their existence, a few Neivamyrmex species are more commonly collected than others because they will occasionally have portions of their raids, or raiding trails, above ground or their workers are found under stones. Borowiec (2016) - Neivamyrmex is the most species-rich and widely distributed genus of New World army ants. The biology of the vast majority of the more than 100 described species is unknown, but Neivamyrmex nigrescens has become one of the best studied dorylines.

At a Glance

• Haiku • Ergatoid queen

Photo Gallery

Neivamyrmex worker. Photo by Gary Alpert.
The tiny Neivamyrmex asper is a leaf-litter raider. Neivamyrmex is the species-richest army ant genus in the Neotropics, but they are very seldom observed, supposedly because they are smaller and have a more cryptic lifestyle than the other army ants. Photo by Phil Hoenle.
Camponotus pennsylvanicus worker that came to harass a Neivamyrmex foraging column proved too much to handle. Nov 2014, East-central Missouri. Photo by James Trager.

Identification

Borowiec (2016) - Worker Neivamyrmex have 12-segmented antennae, propodeal spiracle high on the sclerite, lack conspicuous propodeal lobes, pygidium small and without a central impressed field, waist two-segmented, and pretarsal claws without a tooth. The simple claws distinguish Neivamyrmex workers from all other New World army ant genera (Cheliomyrmex, Eciton, Labidus, and Nomamyrmex). Aenictus in the Old World will also match some of these diagnostic characters but workers of this genus never have more than 10 antennal segments.

Male Neivamyrmex males share the army ant-like habitus with other members of the Eciton genus-group. See discussion under Cheliomyrmex male diagnosis for characters differentiating New World army ant males from those of the Old World. Among the New World army ants, Neivamyrmex can most reliably distinguished by a combination of apex penisvalvae without setae, no dense setation on gaster, and abdominal segment II (petiole) without a deeply notched or concave surface. The bare penisvalvae are shared only with Eciton and Nomamyrmex but the former always has a deeply excavated petiole and the latter has conspicuous tufts of dense setae on the gaster.

See images of species within this genus

Keys including this Genus

Keys to Species in this Genus

Key to US Neivamyrmex

Distribution

Central and southern United States, south to central Argentina.

Distribution and Richness based on AntMaps

Species by Region

Number of species within biogeographic regions, along with the total number of species for each region.

	Afrotropical Region	Australasian Region	Indo-Australian Region	Malagasy Region	Nearctic Region	Neotropical Region	Oriental Region	Palaearctic Region
Species	0	0	0	0	28	122	0	0
Total Species	2841	1736	3045	932	835	4379	1741	2862

Fossils

Fossils are known from: Dominican amber, Dominican Republic (Burdigalian, Early Miocene).

Biology

Borowiec (2016) - The majority of species has never been studied in any detail, and much of what we know comes from the observations made on one relatively common species, Neivamyrmex nigrescens, studied extensively by Howard Topoff and his students (Gotwald 1995). The biology of other species has been summarized by Rettenmeyer (1963).

If N. nigrescens is representative of this genus, the lineage’s habits are similar to those of other New World army ants. There are marked nomadic and statary phases, lasting about 16 and 20 days, respectively. The colonies are of moderate size, containing 80,000 to 140,000 workers (Rettenmeyer 1963; Topoff et al. 1980 estimate 10,000–50,000) and bivouacs are subterranean. The prey consists of almost exclusively other ants’ brood.

Nesting sites of Neivamyrmex are rarely observed. Rettenmeyer (1963) reported that although known bivouac sites of N. nigrescens in Kansas are typically at least 1 meter below the surface, two bivouacs were discovered that were completely contained within the upper 30 cm of the soil. Emigration behavior in this species has been very well described. Environmental factors, such as prey availability/density and nest site availability, influence the emigration behavior (Topoff and Mirenda 1980, Mirenda and Topoff 1980). Neivamyrmex carolinensis and Neivamyrmex kiowapache are unusual among army ants in that they are the only species known to be polygynous, with colonies reported to contain over a dozen queens (Rettenmeyer and Watkins 1978, see also Snelling and Snelling 2007). The queens of N. kiowapache have been shown to mate with much lower frequency than other army ants. This is in accordance with the prediction that the costly multiple matings will be reduced or lost if genetic diversity of workers can be achieved through polygyny (Kronauer and Boomsma 2007b).

The foraging biology of N. nigrescens in Arizona was studied in detail by Mirenda et al. (1980). They reported that these army ants forage at night and raid nests of many other ants and termites. The ants in the genus Pheidole were shown to be the preferred prey, being taken twice as often as expected based on colony density. Pogonomyrmex, Forelius, and Myrmecocystus were reported to be avoided. The authors observed temporal variation in prey composition, noting that as the season progressed and conditions became drier, many of the prey Pheidole species ceased activity and sealed their nests. Neivamyrmex nigrescens was then observed to rely more heavily on Novomessor cockerelli as prey.

Several Neivamyrmex species can occur sympatrically, and it is likely that a diversity of prey preferences exists in the genus. Mirenda et al. (1980) also observed multiple raids of Neivamyrmex harrisii, sympatric with N. nigrescens, and noted that Solenopsis xyloni was the only species being attacked.

Neivamyrmex nigrescens uses both tactile and chemical cues in orientation (Topoff and Lawson 1979).

Many species of ants respond to a Neivamyrmex attack by nest evacuation and this behavior has been highlighted as a tool for collecting colonies of soil-nesting species that are normally difficult to excavate. Smith and Haight (2008) showed that 150-300 Neivamyrmex nigrescens workers poured into the nest entrance of Novomessor cockerelli induced evacuation of a mature colony, including brood and queen.

Association with Other Organisms

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An unknown species is a host for the phorid fly Dacnophora legionis (a parasitoid) (Quevillon, 2018) (encounter mode primary; direct transmission; transmission outside nest).
An unknown species is a host for the phorid fly Dacnophora setithorax (a parasitoid) (Quevillon, 2018) (encounter mode primary; direct transmission; transmission outside nest).

All Associate Records for Genus

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Taxon	Relationship	Associate Type	Associate Taxon	Associate Relationship	Locality	Source	Notes
Neivamyrmex	host	phorid fly	Dacnophora legionis	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex	host	phorid fly	Dacnophora setithorax	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex adnepos	host	phorid fly	Pseudacteon browni	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex alfaroi	associate (details unknown)	phorid fly	Ecitomyia wheeleri	associate (details unknown)		Quevillon, 2018
Neivamyrmex carettei	host	diapriid wasp	Asolenopsia rufa	parasite	Argentina	Loiacono, 2013; Gonzalez et al., 2016
Neivamyrmex carolinensis	associate (details unknown)	phorid fly	Xanionotum hystrix	associate (details unknown)		Quevillon, 2018
Neivamyrmex carolinensis	associate (details unknown)	phorid fly	Xanionotum wasmanni	associate (details unknown)		Quevillon, 2018
Neivamyrmex carolinensis	host	diapriid wasp	Apopria sp.	parasite		www.diapriid.org	potential host
Neivamyrmex carolinensis	host	diapriid wasp	Myrmecopria mellea	parasite		www.diapriid.org
Neivamyrmex cristatus	host	diapriid wasp	Notoxoides cornutus	parasite		www.diapriid.org	potential host
Neivamyrmex diversinodis	host	phorid fly	Cremersia australis	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex gibbatus	associate (details unknown)	phorid fly	Xanionotum bruchi	associate (details unknown)		Quevillon, 2018
Neivamyrmex gibbatus	associate (details unknown)	phorid fly	Xanionotum wasmanni	associate (details unknown)		Quevillon, 2018
Neivamyrmex gibbatus	host	diapriid wasp	Acanthopria sp.	parasite		www.diapriid.org	potential host
Neivamyrmex goeldii	host	diapriid wasp	Mimopria goeldii	parasite		www.diapriid.org
Neivamyrmex goeldii	host	diapriid wasp	Mimopria pentatoma	parasite		www.diapriid.org
Neivamyrmex impudens	associate (details unknown)	phorid fly	Ecitophora costaricensis	associate (details unknown)		Quevillon, 2018
Neivamyrmex legionis	host	diapriid wasp	Euplacopria mutilata	parasite		www.diapriid.org
Neivamyrmex legionis	host	diapriid wasp	Philolestoides wasmanni	parasite		www.diapriid.org
Neivamyrmex legionis	host	diapriid wasp	Szelenyiopria reichenspergeri	parasite	Brazil, Argentina	Loiacono, 1987; Loiacono, 2013; Gonzalez et al., 2016; www.diapriid.org
Neivamyrmex legionis	host	phorid fly	Cremersia costalis	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex legionis	host	phorid fly	Dacnophora legionis	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex minensis	host	diapriid wasp	Neivapria penicillata	parasite		www.diapriid.org
Neivamyrmex nigrescens	associate (details unknown)	phorid fly	Ecitomyia wheeleri	associate (details unknown)		Quevillon, 2018
Neivamyrmex nigrescens	associate (details unknown)	phorid fly	Xanionotum hystrix	associate (details unknown)		Quevillon, 2018
Neivamyrmex nigrescens	associate (details unknown)	phorid fly	Xanionotum wasmanni	associate (details unknown)		Quevillon, 2018
Neivamyrmex nigrescens	host	diapriid wasp	Ecitovagus gibbus	parasite		www.diapriid.org	potential host
Neivamyrmex nigrescens	host	phorid fly	Cremersia sp.	parasite	Arizona, USA	Brown & Fenner, 1998
Neivamyrmex nigrescens	host	phorid fly	Dacnophora pectinatus	parasite	Arizona, USA	Brown & Fenner, 1998
Neivamyrmex nigrescens	predator	ant	Trachymyrmex arizonensis	prey
Neivamyrmex opacithorax	associate (details unknown)	phorid fly	Acontistoptera melanderi	associate (details unknown)		Quevillon, 2018
Neivamyrmex opacithorax	associate (details unknown)	phorid fly	Xanionotum hystrix	associate (details unknown)		Quevillon, 2018
Neivamyrmex opacithorax	associate (details unknown)	phorid fly	Xanionotum wasmanni	associate (details unknown)		Quevillon, 2018
Neivamyrmex opacithorax	host	diapriid wasp	Apopria coveri	parasite		Masner & Garcia, 2002	potential host
Neivamyrmex opacithorax	host	diapriid wasp	Apopria sp.	parasite		www.diapriid.org	potential host
Neivamyrmex opacithorax	host	diapriid wasp	Myrmecopria mellea	parasite		www.diapriid.org
Neivamyrmex opacithorax	host	phorid fly	Megaselia sp.	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex pilosus	associate (details unknown)	phorid fly	Acontistoptera melanderi	associate (details unknown)		Quevillon, 2018
Neivamyrmex pilosus	associate (details unknown)	phorid fly	Ecitomyia wheeleri	associate (details unknown)		Quevillon, 2018
Neivamyrmex pilosus	associate (details unknown)	phorid fly	Ecitophora parva	associate (details unknown)		Quevillon, 2018
Neivamyrmex pilosus	associate (details unknown)	phorid fly	Ecitoptera watkinsi	associate (details unknown)		Quevillon, 2018
Neivamyrmex pilosus	associate (details unknown)	phorid fly	Xanionotum wasmanni	associate (details unknown)		Quevillon, 2018
Neivamyrmex pilosus	host	phorid fly	Cremersia sp.	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex pilosus	host	phorid fly	Pseudacteon simplex	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex pseudops	host	diapriid wasp	Asolenopsia schwarzmaieri	parasite		www.diapriid.org
Neivamyrmex pseudops	host	diapriid wasp	Euplacopria mutilata	parasite		www.diapriid.org
Neivamyrmex pseudops	host	diapriid wasp	Notoxoides pedissequus	parasite	Argentina	Loiacono, 2013; Gonzalez et al., 2016; www.diapriid.org
Neivamyrmex pseudops	host	phorid fly	Cremersia costalis	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex raptor	host	phorid fly	Dacnophora legionis	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex rugulosus	predator	ant	Trachymyrmex arizonensis	prey
Neivamyrmex sulcatus	associate (details unknown)	diapriid wasp	Notoxoides pronotalis	associate (details unknown)		Quevillon, 2018
Neivamyrmex sulcatus	host	diapriid wasp	Notaxoides pronatalis	parasite	Argentina	Loiacono, 2013; Gonzalez et al., 2016
Neivamyrmex sumichrasti	associate (details unknown)	phorid fly	Ecitomyia wheeleri	associate (details unknown)		Quevillon, 2018
Neivamyrmex sumichrasti	associate (details unknown)	phorid fly	Ecitophora collegiana	associate (details unknown)		Quevillon, 2018
Neivamyrmex sumichrasti	associate (details unknown)	phorid fly	Ecitophora comes	associate (details unknown)		Quevillon, 2018
Neivamyrmex sumichrasti	associate (details unknown)	phorid fly	Ecituncula aptera	associate (details unknown)		Quevillon, 2018
Neivamyrmex sumichrasti	associate (details unknown)	phorid fly	Puliciphora borinquenensis	associate (details unknown)		Quevillon, 2018
Neivamyrmex sumichrasti	associate (details unknown)	phorid fly	Xanionotum scopifer	associate (details unknown)		Quevillon, 2018
Neivamyrmex sumichrasti	associate (details unknown)	phorid fly	Xanionotum wasmanni	associate (details unknown)		Quevillon, 2018
Neivamyrmex texanus	associate (details unknown)	phorid fly	Xanionotum scopifer	associate (details unknown)		Quevillon, 2018
Neivamyrmex texanus	host	diapriid wasp	Apopria coveri	parasite		www.diapriid.org	potential host
Neivamyrmex texanus	host	phorid fly	Cremersia adunca	parasitoid		Quevillon, 2018	encounter mode primary; direct transmission; transmission outside nest
Neivamyrmex texanus	predator	ant	Trachymyrmex saussurei	prey

Flight Period

All Flight Records for Genus

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Taxon	Month	Source	Notes
Neivamyrmex klugii distans	Mar • Apr • May • Jun
Neivamyrmex melshaemeri	Apr • May • Jun • Jul • Aug	Smith, 1942
Neivamyrmex nigrescens	Jul	antkeeping.info
Neivamyrmex pilosus	Mar • Apr • May		late dry season to early wet season
Neivamyrmex pseudops	Jan • Feb • Mar • Apr • May • Jun • Jul • Aug • Sep • Oct • Dec	Kaspari et al., 2001
Neivamyrmex swainsonii	Mar • Apr • May	antkeeping.info

Life History Traits

Mean colony size: 110000 (Greer et al., 2021)
Compound colony type: not parasitic (Greer et al., 2021)
Nest site: hypogaeic (Greer et al., 2021)
Diet class: predator (Greer et al., 2021)
Foraging stratum: subterranean/leaf litter (Greer et al., 2021)
Foraging behaviour: cooperative (Greer et al., 2021)

Castes

Morphology

Worker Morphology

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• Antennal segment count: 12 • Antennal club: absent, gradual • Palp formula: 2,3; 2,2 • Total dental count: 1-15(0-1) • Spur formula: 1 pectinate, 1 pectinate • Eyes: 0-1 ommatidia • Pronotal Spines: absent • Mesonotal Spines: absent • Propodeal Spines: absent • Petiolar Spines: absent • Caste: most polymorphic, some species monomorphic • Sting: present • Metaplural Gland: present • Cocoon: absent

Karyotype

All Karyotype Records for Genus

See additional details at the Ant Chromosome Database.

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Taxon	Haploid	Diploid	Karyotype	Locality	Source	Notes
Neivamyrmex texanus		36	36M	USA	Taber & Cokendolpher, 1988

Phylogeny

Dorylinae

Lioponera (76 species, 0 fossil species)

Lividopone (1 species, 0 fossil species)

	Parasyscia (57 species, 0 fossil species)

	Zasphinctus (24 species, 0 fossil species)

Vicinopone (1 species, 0 fossil species)

	Simopone (40 species, 0 fossil species)

	Tanipone (10 species, 0 fossil species)

Eusphinctus (2 species, 0 fossil species)

	Ooceraea (17 species, 0 fossil species)

	Syscia (41 species, 0 fossil species)

Eburopone (2 species, 0 fossil species)

Aenictus (228 species, 0 fossil species)

	Aenictogiton (7 species, 0 fossil species)

	Dorylus (127 species, 0 fossil species)

Cerapachys (6 species, 0 fossil species)

	Chrysapace (4 species, 0 fossil species)

	Yunodorylus (4 species, 0 fossil species)

See Phylogeny of Dorylinae for details.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

NEIVAMYRMEX [Ecitoninae: Ecitonini]
- Neivamyrmex Borgmeier, 1940: 606 [as subgenus of Eciton]. Replacement name for Acamatus Emery, 1894c: 181. [Junior homonym of Acamatus Schoenherr, 1833: 20 (Coleoptera).]
- Neivamyrmex raised to genus: Borgmeier, 1950c: 624.
- Neivamyrmex senior synonym of Woitkowskia: Borgmeier, 1955: 277.
ACAMATUS [junior homonym, see Neivamyrmex]
- Acamatus Emery, 1894c: 181 [as subgenus of Eciton]. Type-species: Eciton (Acamatus) schmitti (junior synonym of Labidus nigrescens), by subsequent designation of Ashmead, 1906: 24; Wheeler, W.M. 1911f: 157. [Junior homonym of Acamatus Schoenherr, 1833: 20 (Coleoptera).]
- Neivamyrmex Borgmeier, 1940: 606, replacement name for Acamatus Emery.
WOITKOWSKIA [junior synonym of Neivamyrmex]
- Woitkowskia Enzmann, E.V. 1952: 443. Type-species: Woitkowskia connectens (junior synonym of Labidus walkerii), by original designation.
- Woitkowskia junior synonym of Neivamyrmex: Borgmeier, 1955: 277.

Taxonomic Notes

Borowiec (2016) - The first species now classified in Neivamyrmex were described from males by William Shuckard in his 1840 series ‘Monograph of the Dorylidae’. Borgmeier later erected the genus (Borgmeier 1940) and cemented its future use with his classification of New World army ants presented in his monographs (Borgmeier 1953, 1955). Borgmeier (1955) also presented an internal classification for the genus with fourteen informal species groups, including five based solely on males as, typically for army ants, numerous names have been proposed for males without associations with workers. Later work on Neivamyrmex taxonomy has been dominated by Julian Watkins who published many new isolated species descriptions and also provided updated identification resources for this and other New World army ant genera, first for New World in general (Watkins 1976) and later for United States in particular (Watkins 1985). This latter resource was recently updated with a publication by Snelling and Snelling (2007). Neivamyrmex is the most species-rich of the Eciton genus-group with 127 extant species. The genus is the sister group to the clade of the other four New World army ant genera and is monophyletic (Borowiec, in prep.). There is no comprehensive internal phylogeny, but preliminary data indicates that some of the species groups proposed by Borgmeier are not monophyletic (Borowiec, in prep.).

Description

Worker

Borowiec (2016) - Head: Antennae with 12 segments. Apical antennal segment not enlarged, not broader and longer than two preceding segments combined. Clypeus with cuticular apron. Lateroclypeal teeth absent. Parafrontal ridges reduced. Torulo-posttorular complex vertical. Antennal scrobes absent. Labrum with median notch or concavity. Proximal face of stipes projecting beyond inner margin of sclerite, concealing prementum when mouthparts fully closed. Maxillary palps 2-segmented. Labial palps 3- or 2-segmented. Mandibles triangular, with teeth. Eyes absent or present, composed of few poorly defined ommatidia. Ocelli absent. Head capsule with differentiated vertical posterior surface above occipital foramen; differentiation sometimes weak. Ventrolateral margins of head without lamella or ridge extending towards mandibles and beyond carina surrounding occipital foramen. Posterior head corners dorsolaterally immarginate. Carina surrounding occipital foramen ventrally absent. Mesosoma: Pronotal flange not separated from collar by distinct ridge or separated by ridge that is low on pronotum. Promesonotal connection with suture completely fused or suture weakly differentiated, immobile. Pronotomesopleural suture completely fused or unfused partway to notal surface. Mesometapleural groove not impressed to weakly impressed. Transverse groove dividing mesopleuron absent or present. Pleural endophragmal pit concavity present. Mesosoma dorsolaterally immarginate. Metanotal depression or groove on mesosoma absent. Metanotal depression or groove on mesosoma present. Propodeal spiracle situated high on sclerite. Propodeal declivity without distinct dorsal edge or margin and rectangular in posterior view. Metapleural gland with bulla visible through cuticle. Propodeal lobes present, short. Metasoma: Petiole anterodorsally immarginate, dorsolaterally immarginate, and laterally above spiracle immarginate. Helcium in relation to tergosternal suture placed at posttergite and axial. Prora forming a simple U-shaped margin or V-shaped protrusion. Spiracle openings of abdominal segments IV–VI circular, oval, or slit-shaped. Abdominal segment III anterodorsally immarginate and dorsolaterally immarginate. Abdominal segment III about half size of succeeding segment IV, which is strongly constricted at presegmental portion (binodal waist). Girdling constriction of segment IV present, i.e. pre- and postsclerites distinct. Cinctus of abdominal segment IV gutter-like and sculptured but not cross-ribbed. Abdominal segment IV conspicuously largest segment. Abdominal tergite IV not folding over sternite, and anterior portions of sternite and tergite equally well visible in lateral view. Girdling constriction between pre- and posttergites of abdominal segments V and VI absent. Girdling constriction between pre- and poststernites of abdominal segments V and VI absent. Pygidium small, reduced to narrow strip, without impressed medial field and simple, usually not armed with cuticular spines or modified setae but occasionally with one or two pairs of thick modified setae. Hypopygium unarmed. Legs: Mid tibia with single pectinate spur. Hind tibia with single pectinate spur. Hind basitarsus not widening distally, circular in cross-section. Posterior flange of hind coxa not produced as raised lamella. Metatibial gland absent to conspicuous patch of whitish cuticle occupying at least half of tibia length. Metabasitarsal gland absent. Hind pretarsal claws simple. Polymorphism: Monomorphic to polymorphic.

Queen

Borowiec (2016) - Dichthadiiform, blind or with very small eyes, without ocelli. Known for several species. See e.g. Watkins (1972) and Wheeler (1921) for descriptions and illustrations of Neivamyrmex gynes.

Male

Borowiec (2016) - Head: Antennae with 13 segments. Clypeus without cuticular apron. Parafrontal ridges absent. Torulo-posttorular complex vertical. Maxillary palps 2-segmented. Labial palps 3- or 2-segmented. Mandibles falcate. Ventrolateral margins of head without lamella or ridge extending towards mandibles and beyond carina surrounding occipital foramen. Carina surrounding occipital foramen ventrally absent. Mesosoma: Pronotal flange not separated from collar by distinct ridge. Notauli absent. Transverse groove dividing mesopleuron absent. Propodeal declivity reduced, without distinct dorsal edge or margin. Metapleural gland opening absent. Propodeal lobes absent or present. Metasoma: Petiole anterodorsally immarginate, dorsolaterally immarginate, and laterally above spiracle immarginate. Helcium in relation to tergosternal suture placed at posttergite and axial. Prora simple, not delimited by carina. Spiracle openings of abdominal segments IV–VI oval or slit-shaped. Abdominal segment III more than half size of succeeding segment IV; latter weakly constricted at presegmental portion (uninodal waist). Girdling constriction of segment IV absent, i.e. pre- and postsclerites indistinct. Cinctus of abdominal segment IV absent, not impressed. Girdling constriction between pre- and postsclerites of abdominal segments V and VI absent. Abdominal segment IV not conspicuously largest segment. Abdominal sternite VII simple. Abdominal sternite IX distally armed with two spines, often with additional projections such as medial spine or paired median denticles, with lateral apodemes longer than much reduced medial apodeme, directed anteriorly (towards head). Genitalia: Cupula very long, nearing or surpassing length of rest of genital capsule and of approximately equal length on both dorsal and ventral surfaces. Basimere narrowly fused to telomere, with sulcus visible at least partway through junction, and ventrally with left and right arms abutting. Telomere expanded at apex. Volsella narrow, hook-shaped or laterally flattened, triangular in lateral view, narrowing towards tip. Penisvalva not flattened at apex, expanded. Legs: Mid tibia with single pectinate spur. Hind tibia with single pectinate spur. Posterior flange of hind coxa not produced as raised lamella. Metatibial gland absent. Metabasitarsal glands absent. Hind pretarsal claws simple or each armed with a tooth. Wings: Tegula present, broad, demiovate in shape. Vein C in fore wing present. Pterostigma broad. Abscissa R·f3 present, running toward distal wing margin and enclosing cell with Rs·f5. Abscissae Rs·f2–3 present, connecting with Rs+M&M·f2. Cross-vein 2r-rs present, differentiated from Rs·f4 by presence of Rs·f2–3. Abscissae Rs·f4–5 differentiated into Rs·f4 and Rs·f5 by 2rs-m. Abscissa M·f2 in fore wing present, separated from Rs+M by Rs·f2. Abscissa M·f4 in fore wing present, reaching wing margin. Cross-vein 1m-cu in fore wing present. Cross-vein cu-a in fore wing present, arising from Cu and distal to, at or near M·f1. Vein Cu in fore wing present, with both branches Cu1 and Cu2. Vein A in fore wing with abscissae A·f1 and A·f2 present. Vein C in hind wing present. Vein R in hind wing present, reaching distal wing margin. Vein Sc+R in hind wing present. Abscissa Rs·f1 in hind wing present, shorter than 1rs-m. Abscissa Rs·f2 in hind wing present, reaching wing margin. Cross-vein 1rs-m in hind wing present, about as long as M·f1. Vein M+Cu in hind wing present. Abscissa M·f1 in hind wing present. Abscissa M·f2 in hind wing present. Cross-vein cu-a in hind wing present. Vein Cu in hind wing present. Vein A in hind wing with abscissae A·f1 and A·f2 present.

Larva

Borowiec (2016) - Described in Wheeler and Wheeler 1984.

References

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