Melophorus brevignathus

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Melophorus brevignathus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Formicinae
Tribe: Melophorini
Genus: Melophorus
Species group: biroi
Species complex: brevignathus
Species: M. brevignathus
Binomial name
Melophorus brevignathus
Heterick, Castalanelli & Shattuck, 2017

Melophorus brevignathus major side ANIC32-900055.jpg

Melophorus brevignathus major top ANIC32-900055.jpg

Specimen labels

Evolutionary Relationships
Melophorus


Melophorus ludius species group



Melophorus potteri species group





Melophorus aeneovirens species group




Melophorus biroi species group (biroi species complex)




Melophorus biroi species group (wheeleri species complex)




Melophorus biroi species group (brevignathus species complex)



Melophorus biroi species group (fieldi species complex)







Based on Heterick et al., 2017. Only selected species groups/complexes are included.

This species has been collected in box pine scrub over red soil and in savanna woodland.

Identification

Heterick et al. (2017) - Melophorus brevignathus can be placed in the Melophoprus biroi species-group on the basis of characters of the clypeus, propodeum, mandible and palps. Furthermore, this species can also be placed in the Melophoprus brevignathus species-complex. This species-complex has the following diagnostic characters: in full-face view the head capsules of the major, media and minor workers are square with small, flattened eyes (except in the media and minor workers of Melophorus marmar, which have a large, convex eye [but the eye is flattened in the major worker]); in profile, the eyes are placed anteriad of the midline of head capsule; the anterior margin of the clypeus is distinctly sinuate, projecting anteromedially as a bluntly triangular extension or flattened dimple in major and media workers; the five-toothed mandible of all workers is very narrow, parallel and coarsely striate throughout its length (broader and more finely striate in most members of the Melophoprus fieldi complex and the Melophoprus biroi complex); and the maxillary palps in all workers is short, barely attaining neck sclerite at their greatest extension and often only reaching the midpoint of venter of head capsule when the head is moderately inclined. The eye of Melophorus brevignathus is placed low on head capsule, its bottom third intersected by an imaginary horizontal line separating head capsule (excluding mandibles) into equal upper and lower sectors, thus separating it from Melophorus quadratus. The species can be distinguished from Melophorus marmar by the following: in full-face view, the head is distinctly convex and the appressed setae on the first gastral tergite in all workers are shorter and separated from the preceding and succeeding rows by at least 2× their own length. The eyes of the minor worker are similar to those of major worker.

Melophorus brevignathus is distinguished from Melophorus quadratus by the position of the eye towards the middle of the head capsule, and from Melophorus marmar by other details of the head capsule, the size of the eyes in the minor worker and the appearance of the setae on the first gastral tergite.

Distribution

QLD and NT.

Distribution based on Regional Taxon Lists

Australasian Region: Australia (type locality).

Distribution based on AntMaps

AntMapLegend.png

Distribution based on AntWeb specimens

Check data from AntWeb

Biology

Castes

Worker

Nomenclature

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

  • brevignathus. Melophorus brevignathus Heterick, Castalanelli & Shattuck, 2017: 219, fig. 48 (w.) AUSTRALIA.

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

Description

Worker

(n = 6): CI 109–112; EI 16–23; EL 0.21–0.26; HL 0.84–1.44; HW 0.92–1.62; ML 1.00–1.56; MTL 0.67–1.02; PpH 0.12–0.18; PpL 0.41–0.63; SI 66–84; SL 0.77–1.06.

Minor. Head. Head square; posterior margin of head weakly concave; frons shining with superficial shagreenation or microreticulation only; frons consisting exclusively or almost exclusively of well-spaced, appressed setae only (small, erect setae, if present, usually confined to ocular triangle or posterior margin of head). Eye moderate (eye length 0.20–0.49 length of side of head capsule); in full-face view, eyes set above midpoint of head capsule; in profile, eye set anteriad of midline of head capsule; eyes elliptical or slightly reniform. In full-face view, frontal carinae straight, divergent posteriad; frontal lobes straight in front of antennal insertion. Anteromedial clypeal margin sinuate with anteromedial dimple; clypeal psammophore set below midpoint of clypeus; palp formula 6,4. Mandibular teeth in minor worker four to five; mandibles narrow, mandibular blade truncate, internal and external margins parallel or nearly so; third mandibular tooth distinctly shorter than apical tooth and tooth no. two, tooth no. four vestigial; masticatory margin of mandibles approximately vertical or weakly oblique. Mesosoma. Integument of pronotum, mesonotum and mesopleuron moderately shining and shagreenate throughout; anterior mesosoma in profile broadly convex; appearance of erect pronotal setae short, (i.e., longest erect setae shorter than length of eye) and unmodified, or erect pronotal setae absent; in profile, metanotal groove shallow, broadly V or U-shaped; propodeum shining and microreticulate; propodeum angulate, propodeal angle blunt; length ratio of propodeal dorsum to its declivity between 1:1 and 1:2; erect propodeal setae always absent; appressed propodeal setulae short, separated by more than own length and inconspicuous; propodeal spiracle situated on or beside declivitous face of propodeum, and shorter (length < 0.50 × height of propodeum). Petiole. In profile, petiolar node squamiform; in full-face view, shape of petiolar node tapered with blunt vertex; node shining and distinctly microreticulate. Gaster. Gaster shining with superficial microreticulation; pilosity of first gastral tergite consisting of well-spaced, erect and semi-erect setae interspersed with regularly placed appressed setae. General characters. Colour of foreparts brown to dark brown, gaster blackish-brown.

Major. Head. Head as for minor worker; posterior margin of head weakly concave; cuticle of frons shining with superficial shagreenation or microreticulation only; frons consisting exclusively or almost exclusively of well-spaced, appressed setae only (small, erect setae, if present, usually confined to ocular triangle or posterior margin of head). Eye moderate (eye length 0.20–0.49 length of head capsule); in full-face view, midpoint of head capsule; in profile, eye set anteriad of midline of head capsule; eyes elliptical. In full-face view, frontal carinae straight, divergent posteriad; frontal lobes straight in front of antennal insertion, or curved inward in front of antennal insertion. Anterior clypeal margin sinuate with anteromedial dimple; clypeal psammophore set below midpoint of clypeus; palp formula 6,4. Mandibular teeth in major worker 4-5; mandibles narrow, mandibular blade truncate, internal and external margins parallel or nearly so; third mandibular tooth distinctly shorter than apical tooth, but equivalent in length to remaining teeth; masticatory margin of mandibles approximately aligned vertically or weakly oblique. Mesosoma. Integument of pronotum, mesonotum and mesopleuron moderately shining and shagreenate throughout; anterior mesosoma in profile broadly convex; erect pronotal setae short, (i.e., shorter than length of eye) and unmodified; in profile, metanotal groove shallow, broadly V- or U-shaped; propodeum shining and finely striolate and microreticulate; propodeum angulate, propodeal angle blunt; length ratio of propodeal dorsum to its declivity between 1:1 and 1:2; erect propodeal setae absent; appressed propodeal setae short, separated by more than own length and inconspicuous; propodeal spiracle situated on or beside declivitous face of propodeum, and shorter (length less than 0.50 × height of propodeum). Petiole. In profile, petiolar node squamiform; in full-face view, shape of petiolar node uniformly rounded, or tapered with blunt vertex; node shining and distinctly microreticulate. Gaster. Gaster shining with superficial microreticulation; pilosity of first gastral tergite consisting of well-spaced, erect and semi-erect setae interspersed with regularly spaced appressed setae, or consisting of short, bristly, erect setae over well-spaced, short, appressed setae. General characters. Colour of foreparts reddish-brown or brown, gaster blackish-brown.

Type Material

Holotype minor worker (bottom ant) from Saint George [sic], Queensland, 15 January 1965, B.B. Lowery, sav. Woodland, ANIC Ants Vial 20.216 [ANIC32-900055] (Australian National Insect Collection). Paratypes: 2 major workers on same pin and with same details as holotype (ANIC); 2 minor workers from Kunoth Paddock, Northern Territory on separate pin but with exactly the same details but lacking small label ‘10’ (The Natural History Museum); 2 media workers and a minor worker from Kunoth Paddock, near Alice Springs, Northern Territory, 26 October 1974, P.J.M. Greenslade, (12), 10 (Museum of Comparative Zoology); 2 major workers and a minor worker from 75 km W of Sandringham HS, Queensland, 6 June 1980, P.J.M. Greenslade, (5), 20) (Queensland Museum).

Etymology

Latin brevis (‘short’) plus Neo-Latin gnathus (‘jaw’); adjective in the nominative singular.

References