Crematogaster malahelo

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Crematogaster malahelo
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Crematogastrini
Genus: Crematogaster
Species: C. malahelo
Binomial name
Crematogaster malahelo
Blaimer, 2013

Crematogaster malahelo casent0317768 p 1 high.jpg

Crematogaster malahelo casent0317768 d 1 high.jpg

Specimen Labels

Crematogaster malahelo is a rare species endemic to montane forest of the central highlands in Madagascar. It has been collected from only three locations, all of which harbor unprotected, rather disturbed forest fragments (SF Manjakatompo, Andranorovitra, Kaloy). Given this restricted distribution the species is exclusively sympatric with Crematogaster mafybe and allopatric with the rest of the C. degeeri-assemblage. The few collections have been made from dead twigs above the ground, indicating arboreal nesting preferences. (Blaimer and Fisher 2013)

Identification

Blaimer and Fisher (2013) - Crematogaster degeeri assemblage. Workers of Crematogaster malahelo can usually be distinguished from other species in the C. degeeri-assemblage given the characteristic promesonotal structure with a propodeum usually distinctly set off from the promesonotum in lateral view. Crematogaster alafara could cause possible confusion with this species, but C. malahelo bears sharp lateral margins on the pronotum (absent in C. alafara) and has shorter, triangular spines (SPI 0.03-0.07).

Keys including this Species

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -18.11199951° to -19.382667°.

 
North
Temperate
North
Subtropical
Tropical South
Subtropical
South
Temperate

Distribution based on Regional Taxon Lists

Malagasy Region: Madagascar (type locality).

Distribution based on AntMaps

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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.
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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.
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Biology

Castes

Known only from the worker caste.

Images from AntWeb

Crematogaster malahelo casent0317768 d 2 high.jpgCrematogaster malahelo casent0317768 p 3 high.jpgCrematogaster malahelo casent0317768 d 3 high.jpg
Holotype of Crematogaster malaheloWorker. Specimen code casent0317768. Photographer Estella Ortega, uploaded by California Academy of Sciences. Owned by CAS, San Francisco, CA, USA.

Nomenclature

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

  • malahelo. Crematogaster malahelo Blaimer, in Blaimer & Fisher, 2013b: 44, fig. 17 (w.) MADAGASCAR.
    • Type-material: holotype worker, 4 paratype workers.
    • Type-locality: holotype Madagascar: Antananarivo, Kalog, 1423 m., 18°35.39’S, 47°39.06’E, 27.iv.2007, BLF17431, disturbed montane rainforest (B.L. Fisher, et al.); paratypes with same data.
    • Type-depositories: CASC (holotype); MCZC, MHNG, SAMC, UCDC (paratypes).
    • Distribution: Madagascar.

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

Description

Worker

(n = 10) [holotype] HW 0.86-1.03 [0.93]; HL 0.80-0.94 [0.80]; EL 0.18-0.24 [0.20]; SL 0.63-0.71 [0.63]; WL 0.92-1.08 [0.94]; SPL 0.03-0.07 [0.05]; PTH 0.19-0.25 [0.21]; PTL 0.25-0.31 [0.29]; PTW 0.33- 0.43 [0.43]; PPL 0.15-0.20 [0.17]; PPW 0.28-0.37 [0.34]; LHT 0.64-0.77 [0.67]; CI 1.03-1.16 [1.16]; OI 0.22-0.26 [0.25]; SI 0.74-0.80 [0.79]; SPI 0.03-0.07[0.06]; PTHI 0.66-0.82 [0.72]; PTWI 1.24-1.52 [1.52]; PPI 1.71-2.04 [2.04]; LBI 1.36-1.53 [1.40].

Small to medium size (HW 0.86-1.03, WL 0.92-1.08). Masticatory margin of mandibles with four teeth; head shape fairly quadrate or slightly wider than long (CI 1.03-1.16); posterior margin of head in full-face view laterally subangular or rounded, sometimes slightly medially depressed; occipital carinae distinct; antennal scapes usually about reaching or surpassing head margin; midline of eyes situated at or slightly above midline of head in full-face view; eyes moderately large (OI 0.22-0.26), slightly protruding. Pronotum laterally angular, with sharp, raised margins; promesonotal suture indistinct, mesonotum more or less forming one plane with pronotum, but often the two separated by distinct variation in sculpture (see below); mesonotum usually without a distinct posterior face; laterally mesonotum angular to carinate, often with posterolateral denticles setting off the promesonotum distinctly from propodeum; metanotal groove fairly shallow, laterally constricted; propodeal spines very short (SPI 0.03-0.07), triangular dents or spines; dorsal face of propodeum distinct, convex; posterior face of propodeum steeply sloping; petiole in dorsal view from broadly to strongly flared and usually strongly concave, dorsolaterally carinate but without posterolateral tubercules or denticles; subpetiolar process usually present as small rounded tooth; postpetiole wider than long, very distinctly bilobed, with broad median impression; subpostpetiolar process absent. Head sculpture shiny to aciculate; pronotum dorsally costulate and contrasting abruptly with a shiny to aciculate mesonotum; dorsal face of propodeum carinulate or reticulate; rest of mesosoma, petiole and postpetiole aciculate to reticulate; face usually with < four erect, longer setae, and regular, shorter, appressed to suberect pubescence; promesonotum usually with < eight erect, long setae; otherwise promesonotum dorsally with sparse appressed to subdecumbent pubescence; petiole and postpetiole usually with a pair of short, erect setae posterolaterally, and shorter suberect, decumbent or appressed pubescence; abdominal tergites four to seven with sparse, short, erect pilosity, more abundant and longer on sternites four to seven, and regular appressed to decumbent pubescence throughout. Color reddish brown to dark brown.

Type Material

Holotype Worker: pinned, CASENT0317768, BLF17431, ex dead twig above ground [imaged on AntWeb]; original locality label: MADG’R: Kaloy, 1423 m, 18º35.39’S, 47º39.06’E, 27 Apr. 2007, disturbed montane rainforest, Fisher et al., BLF#; deposited at California Academy of Sciences. Paratypes 4 workers, pinned. #1: CASENT0317767, deposited at South African Museum. #2: CASENT0317769, deposited at Musee d'Histoire Naturelle Genève. #3: CASENT0317770, deposited at Museum of Comparative Zoology. #4: CASENT0317771, deposited at University of California, Davis. #1 and # 2 same collection and locality data as holotype. #3 and #4: BBB004, on tree trunk, Station Forestière Manjakatompo, -19.37083, 47.33900, 1575 m, disturbed montane rainforest, 31 Mar. 2007, B.B.Blaimer. MADAGASCAR: Antananarivo: Kaloy: -18.58998, 47.65102, 1423 m, disturbed montane rainforest.

Etymology

The Malagasy word malahelo means “sad.” This name alludes to the rather sad fact that all three of the montane rainforest locations where this species is known to occur is heavily disturbed. The name is treated as noun in apposition.

References

References based on Global Ant Biodiversity Informatics

  • Blaimer B. B., and B. L. Fisher. 2013. Taxonomy of the Crematogaster degeeri-species-assemblage in the Malagasy region (Hymenoptera: Formicidae). European Journal of Taxonomy 51: 1-64.