Crematogaster razana

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Crematogaster razana
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Crematogastrini
Genus: Crematogaster
Species: C. razana
Binomial name
Crematogaster razana
Blaimer, 2012

Crematogaster razana casent0149655 p 1 high.jpg

Crematogaster razana casent0149655 d 1 high.jpg

Specimen Labels

Crematogaster razana has only been collected at two localities in southern Madagascar. One of these sites is a dry forest (western slopes of P.N. Andohahela), whereas the other collections were made in a montane grassland habitat (R.S. Kalambatritra). Since the few collections of this rare species have been made mostly on the ground (under stone, pitfall trap or on low vegetation), I assume that C. razana is ground-nesting. This species is sympatric with Crematogaster rasoherinae and parapatric or narrowly sympatric with both Crematogaster madecassa and Crematogaster telolafy in the Andohahela massif. (Blaimer 2012)


Blaimer (2012) - A member of the Crematogaster madecassa group. A combination of protruding eyes and raised sharp lateral carinae on the propodeum separates workers of C. razana from workers of Crematogaster rasoherinae and the C. volamena-group. From other species within the C. madecassa-group it can be identified by the lack of median vertical carinae on the clypeus and the absence of long setae on the posterior end of the lateral mesonotal carinae. Crematogaster razana queens are diagnosed by a combination of the presence of very short propodeal spines, large protruding eyes (OI 0.31), and the presence of a median clypeal notch.

Keys including this Species


Latitudinal Distribution Pattern

Latitudinal Range: -19.006727° to -24.93°.

Tropical South

Distribution based on Regional Taxon Lists

Malagasy Region: Madagascar (type locality).

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.



Males have yet to be collected.


Images from AntWeb

Crematogaster razana casent0149655 h 2 high.jpgCrematogaster razana casent0149655 p 2 high.jpg
Holotype of Crematogaster razanaWorker. Specimen code casent0149655. Photographer Bonnie Blaimer, uploaded by Curator Bonnie Blaimer. Owned by CAS, San Francisco, CA, USA.


Images from AntWeb

Crematogaster razana casent0148782 h 1 high.jpgCrematogaster razana casent0148782 d 1 high.jpgCrematogaster razana casent0148782 p 1 high.jpgCrematogaster razana casent0148782 p 2 high.jpgCrematogaster razana casent0148782 h 2 high.jpgCrematogaster razana casent0148782 l 1 high.jpg
Queen (alate/dealate). Specimen code casent0148782. Photographer Bonnie Blaimer, uploaded by Curator Bonnie Blaimer. Owned by CAS, San Francisco, CA, USA.


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

  • razana. Crematogaster razana Blaimer, 2012b: 55, fig. 30 (w.q.) MADAGASCAR.
    • Type-material: holotype worker.
    • Type-locality: Madagascar: Prov. Toliara, R.S.. Kalambatritra, 23.4185°S, 46.4583°E, 1365 m., 8.ii.2009, BLF21485, grassland (B.L. Fisher, et al.).
    • Type-depository: CASC.
    • Combination in C. (Orthocrema): Blaimer, 2012b: 32.
    • Distribution: Madagascar

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



(n=3). Holotype: HW 0.54; HL 0.50; EL 0.13; SL 0.37; WL 0.53; SPL 0.07; PTH 0.12; PTL 0.18; PTW 0.15; PPL 0.12; PPW 0.16; LHT 0.38; CI 1.08; OI 0.26; SI 0.74; SPI 0.14; PTHI 0.68; PTWI 0.86; PPI 1.31; LBI 1.40.

Other material. HW 0.49–0.56; HL 0.45–0.52; EL 0.12–0.14; SL 0.35–0.40; WL 0.45–0.54; SPL 0.05–0.07; PTH 0.10–0.12; PTL 0.15–0.19; PTW 0.14–0.16; PPL 0.08–0.11; PPW 0.14–0.17; LHT 0.34–0.40; CI 1.07; OI 0.26–0.27; SI 0.76–0.77; SPI 0.11–0.13; PTHI 0.64–0.67; PTWI 0.86–0.92; PPI 1.46–1.70; LBI 1.32–1.37.

Very small species (HW 0.49–0.56, WL 0.45–0.54), with characters of the C. madecassa-group, in addition to the following. Clypeus lacking median vertical carinae; antennal scapes just reaching posterior margin of head.

Metanotal groove constricted to about half the width of pronotum; propodeal spines short (SPI 0.11–0.14), in form of acute triangular points, distinctly directed upwards in lateral view, in dorsal view moderately diverging; subpostpetiolar process absent.

Face with no more than 4 erect, long flexuous setae; promesonotum with 4 erect, long flexuous setae: 2 humeral setae, and 2 setae at anterior end of mesonotal carinae (posterior setae absent). Color yellow to yellowish-brown.


(n=1). HW 1.10, HL 0.91, EL 0.28, SL 0.65, MSNW 0.94, MSNL 0.98, WL 1.74, SPL 0.04, PTH 0.30, PTL 0.45, PTW 0.41, PPL 0.28, PPW 0.46, LHT 0.83, CI 1.21, OI 0.31, SI 0.71, MSNI 1.77, SPI 0.02, PTHI 0.66, PTWI 0.92, PPI 1.65, LBI 2.09.

Very small (HW 1.10, WL 1.74), with characters of the C. madecassa-group, in addition to the following. Clypeus with a median notch; antennal scapes just reaching posterior margin of head.

Mesosoma more compact (MSNI 1.77, WL 1.74); mesoscutum in dorsal view about as wide as long; propodeal spines reduced to minute dents (SPI 0.02).

Petiole with one pair of long flexuous setae posterior to denticles.

Type Material

MADAGASCAR: Toliara: R.S. Kalambatritra: -23.4185, 46.4583, 1365m, grassland, under stone; 8.ii.2009; B. L. Fisher et al..

Holotype worker: pinned, CASENT0149655, BLF21485; original locality label: MADG’R: Toliara: R.S. Kalambatritra: 23.4185°S, 46.4583°E, 1365m; grassland, 8.ii.2009; B. L. Fisher et al. BLF#; deposited at California Academy of Sciences.


The Malagasy word “razana” means ancestor and alludes to the isolated distribution of this species and its phylogenetic position within the C. madecassa-group. This name should be treated as a noun in apposition.


References based on Global Ant Biodiversity Informatics

  • Blaimer B. B. 2012. Acrobat ants go global – Origin, evolution and systematics of the genus Crematogaster (Hymenoptera: Formicidae). Molecular Phylogenetics and Evolution 65: 421-436.
  • Blaimer B. B. 2012. Taxonomy and species-groups of the subgenus Crematogaster (Orthocrema) in the Malagasy region (Hymenoptera, Formicidae). ZooKeys 199: 23-70