Mystrium silvestrii

Mystrium silvestrii
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Amblyoponinae
Tribe:	Amblyoponini
Genus:	Mystrium
Species group:	camillae
Species:	M. silvestrii
Binomial name
	Mystrium silvestrii; Santschi, 1914 Specimen labels

Nothing is known about the biology of Mystrium silvestrii.

Identification

The only Mystrium found on the African continent.

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: 6.5° to 5.5°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: AntMaps

Distribution based on Regional Taxon Lists

Afrotropical Region: Cameroun (type locality), Central African Republic.

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Explore Overview of Mystrium biology

Mystrium are predators that specialize on capturing large centipedes. The long mandibles appear to be adapted to gripping what can be fast moving centipedes, and hold them in place to allow their being stung in the softer areas between their body segments. Foragers carrying out this task also need to have strong mandibular muscles that combined with their long mandbiles may compromise their efficiency in regards to brood care. Mystrium rogeri exhibits caste polymorphism where large workers appear to be specialized for foraging while smaller workers are adapted to specialize on brood care. Colonies of Mystrium oberthueri have large workers and many small reproductives. The vast majority of the the latter do not mate, do not leave the nest and both care for brood and are active in cleaning their nests. Colony size tends to be small (< 200 workers) and in some species, e.g., Mystrium rogeri, reproduction is based on having a single large queen morph that found nests independantly. In others, intermoph queens exist and colony founding can occur via fission.

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Castes

Worker

Images from AntWeb


Worker. Specimen code casent0102167. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by NHMUK, London, UK.


Worker. Specimen code casent0101135. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by NHMB, Basel, Switzerland.


Worker. Specimen code casent0101977. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by MHNG, Geneva, Switzerland.


Worker. Specimen code casent0006824. Photographer April Nobile, uploaded by California Academy of Sciences.


Worker. Specimen code casent0172832. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by MCZ, Cambridge, MA, USA.


Worker. Specimen code casent0408192. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by CAS, San Francisco, CA, USA.

Queen

Images from AntWeb


Queen (alate/dealate). Specimen code casent0101136. Photographer April Nobile, uploaded by California Academy of Sciences.	Owned by NHMB, Basel, Switzerland.

Nomenclature

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

silvestrii. Mystrium silvestrii Santschi, 1914d: 310, fig. 1 (w.q.) CAMEROON.
- Type-material: 3 syntype workers, 1 syntype queen.
- Type-locality: Cameroon: Victoria (F. Silvestri).
- Type-depository: NHMB.
- [Note: only one syntype worker is present in NHMB (Baroni Urbani, 1973b: 126); presumably the other syntypes are in DEUN.]
- Status as species: Wheeler, W.M. 1922a: 758; Menozzi, 1929d: 534 (redescription); Brown, 1960a: 170; Bolton, 1995b: 287.
- Distribution: Cameroon, Ghana, Ivory Coast.

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

Description

Worker

Long. 5,8 mill. (sans les mandibules). D'un brun roussatre fonce. Devant de la tete, mandibules, antennes, pattes et gastre d'un roux plus ou moins dilue. Tarses et anus jaunes. Mate. Tete, thorax et deux premiers segments abdominaux (petiole et postpetiole) grossierement ride reticule en grosses fossettes a fond luisant, irise, presque lisse, avec un point median d'ou emerge une courte soie squameuse, jaunatre. Sur les 3eme et 4eme segments abdominaux les rides deviennent franchement longitudinales sans former de reticulations, et s' effacent sur les derniers segments qui sont finement et densement ponctues avec la base tres finement reticulee en travers. Fossettes antennaires et cotess de l' epistome rides en long. Mandibules, antennes et pattes plus superficiellement ridees reticulees, le tout densement ponctue dans les intervales sauf les mandibules qui n'ont qu'un point entre les reticules donnant naissance a une soie courte et simple. Les soies squamiformes sont bien plus courtes que chez M. Voelzkowi. For. et partont repandues sur le corps et les pattes; elles se rangent le long de la face interne des mandibules. Sur le bord des segments du gastre elles sont aussi un peu plus longues et melangee, de quelque longues soies epaisses. Les tarses sont en outre epineux. Pubescence courte, epaisse, tres rare partout sauf sur le funicule.

Tete plus large que longue, fortement echancree derriere, les cotes convexes en arriere et concaves en avant, termines aux angles anterieurs par deux fortes epines plus lonques que chez M. Voelzkowi For. Une impression plus ou moins profonde sur le vertex. Yeux tres petits (plus petits que chez Myrmica mysticum) peu distincts places au milieu des cotes. Epistome un peu plus long et moin abrupt que chez M. mysticum a bord anterieur egalement arque et denticule. Le scape depasse un peu le milieu des cotes de la tete. Articles 9 et 10 du funicule bien plus epais que longs. le 11eme moins d'un quart plus long que large. L' extremite des mandibules est distinctement spatuliforme, plus elargie que chez M. mysticum et Voelzkowi. Les dents sont plus petites, le rang superieur en compte 11 environ qui s'avancent jusqu' a l'extremite ou elles sont tres basses et tres allongees. Thorax retreci au niveau du mesonotum qui est distinctement limite en avant et en arriere. Pronotum aussi long que large dans son tiers posterieur. La face basale de l'epinotum plus large que longue, plane fait un angle de 115 avec la face declive. Noeud du pedicule trois fois aussi large que long. Abdomen peu etrangle apres le postpetiole qui est double plus large que long. Pattes courtes.

Queen

Long. 6 mill. Ne differe de l'ouvriere que par les caracteres ordinaires du thorax et l'abdomen legerement plus epais.

Type Material

Cameronn: Victoria 3 w 1 q. C'est la premiere espece du genre trouyee sur le continant africain.

References

Menozzi, C. 1929e. Revisione delle formiche del genere Mystrium Roger. Zool. Anz. 82: 518-536 (page 534, see also)
Santschi, F. 1914d. Formicides de l'Afrique occidentale et australe du voyage de Mr. le Professeur F. Silvestri. Boll. Lab. Zool. Gen. Agrar. R. Sc. Super. Agric. 8: 309-385 (page 310, fig. 1 worker, queen described)
Yoshimura, M. & Fisher, B.L. 2014. A revision of the ant genus Mystrium in the Malagasy region with description of six new species and remarks on Amblyopone and Stigmatomma (Hymenoptera, Formicidae, Amblyoponinae). ZooKeys 394, 1–99.

References based on Global Ant Biodiversity Informatics

Kone M., S. Konate, K. Yeo, P. K. Kouassi, and K. E. Linsenmair. 2012. Changes in ant communities along an age gradient of cocoa cultivation in the Oumé region, central Côte dIvoire. Entomological Science 15: 324339.
Lévieux J. 1972. Les fourmis de la savane de Lamto (Côte d'Ivoire): éléments de taxonomie. Bulletin de l'Institut Fondamental d'Afrique Noire. Série A. Sciences Naturelles 34: 611-654.
Lévieux J. 1977. La nutrition des fourmis tropicales: V- Elements de synthèse. Les modes d'exploitation de la biocenose. Insectes Sociaux 24(3): 235-260.
Menozzi C. 1929. Revisione delle formiche del genere Mystrium Roger. Zoologischer Anzeiger. 82: 518-536.