Crematogaster mafybe Blaimer, 2013

Blaimer, Bonnie B. & Fisher, Brian L., 2013, Taxonomy of the Crematogaster degeeri-species-assemblage in the Malagasy region (Hymenoptera: Formicidae), European Journal of Taxonomy 51, pp. 1-64 : 35-39

Crematogaster mafybe Blaimer sp. nov.

urn:lsid:zoobank.org:act:66E18466-A2C6-4EA5-A92D-1D74D7A74CC5

Figs 13-14

Diagnosis

Crematogaster mafybe sp. nov. can be readily distinguished by its small eyes (OI 0.18 - 0.21) and lack of pronotal spines. These characters are otherwise only shared with C. lobata ; from the latter C. mafybe sp. nov. can be distinguished by the presence of a distinct median longitudinal groove on the pronotum. Our data shows a mean sequence divergence between C. mafybe sp. nov. and the other species in the C. degeeri -assemblage of 12.7 - 21.3 % ( Table 3 ).

Etymology

The Malagasy word mafybe means “very strong”, as this species is one of the largest and most robust Crematogaster species in Madagascar. The name is treated as a noun in apposition.

Type specimens

Holotype

Worker: pinned, CASENT0317762 , BBB224 , ex dead tree [imaged on AntWeb]; original locality label: M’dgascar: Fianarantsoa: P.N.Andringitra, 15.5 km S Ambalamanenjana, 1730 m, 22º12.453’S, 46º58.314’E, 4 Mar. 2010, montane rainforest, B.B.Blaimer, BBB224; deposited at CASC.

Paratypes

4 workers, pinned, same collection and locality data as holotype. #1: CASENT0317793 , deposited at SAMC; #2. CASENT0317794 , deposited at MHNG. #3: CASENT0317795 , deposited at MCZC. #4: CASENT0317796 , deposited at UCDC.

Type locality

MADAGASCAR: Fianarantsoa: P.N. Andringitra : -22.2076, 46.9719, 1730 m, montane rainforest.

Other material examined

(BBBC, CASC, MCZC, PSWC): refer to Supplementary Material 1.

Worker

Measurements

(n = 21) [holotype] HW 0.98 - 1.43 [1.24]; HL 0.89 - 1.30 [1.16]; EL 0.18 - 0.27 [0.21]; SL 0.63 - 0.94 [0.83]; WL 0.98 - 1.48 [1.26]; SPL 0.00 - 0.03 [0.02]; PTH 0.19 - 0.27 [0.22]; PTL 0.27 - 0.44 [0.35]; PTW 0.34 - 0.52 [0.45]; PPL 0.16 - 0.25 [0.23]; PPW 0.26 - 0.40 [0.33]; LHT 0.76 - 1.23 [0.98]; CI 1.04 - 1.11 [1.07]; OI 0.18 - 0.21 [0.18]; SI 0.60 - 0.79 [0.72]; SPI 0.00 - 0.03 [0.01]; PTHI 0.59 - 0.84 [0.62]; PTWI 1.06 - 1.41 [1.27]; PPI 1.39 - 1.79 [1.45]; LBI 1.15 - 1.42 [1.29].

Description

( Fig.13A - C ) Medium to very large size (HW 0.98 - 1.43, WL 0.98 - 1.48).

Masticatory margin of mandibles with four teeth; head shape quadrate, more or less as long as wide (CI 1.04 - 1.11); posterior margin of head in full-face view laterally angular or subangular, sometimes medially depressed; occipital carinae usually distinct; antennal scapes of variable length, not reaching or surpassing head margin; midline of eyes situated at midline of head in full-face view; eyes small (OI 0.18 - 0.21), and confluent with lateral head margin in full-face view.

Pronotum laterally angular; promesonotal suture usually indistinct, the mesonotum more or less forming one plane with pronotum; pronotum with a longitudinal groove; mesonotum usually without distinct posterior face; mesonotum laterally angular, ending in small posterolateral tubercules; metanotal groove fairly shallow; propodeal spines absent, or propodeum with small denticules or tubercules; dorsal face of propodeum very short to absent, posterior face of propodeum sloping fairly steeply, often with sharp transverse groove; petiole in dorsal view broadly oval to moderately flared, concave, without dorsolateral carinate margins and posterolateral tubercules or denticles; subpetiolar process variable, but often entirely absent; postpetiole bilobed with a narrow to broad median impression; subpostpetiolar process absent.

Head sculpture carinulate to reticulate; promesonotum carinulate to reticulate; propleuron reticulate, mesopleuron areolate, metapleuron reticulate-carinulate; dorsal face of propodeum carinulate to reticulate, posterior face reticulate; petiole and postpetiole dorsally and ventrally reticulate; erect pilosity on face sparse, <eight longer setae, and abundant, short, appressed to suberect pubescence; erect pilosity on promesonotum variable, usually <12 long setae; otherwise promesonotum dorsally with very sparse appressed to subdecumbent pubescence; petiole and postpetiole usually with a pair of short erect setae posterolaterally, and shorter appressed pubescence; abdominal tergites four to seven with very sparse short erect pilosity, ventrally more abundant, and regular appressed to decumbent pubescence throughout. Color black or brown, abdominal segments four to seven yellowish.

Queen

Measurements

(n = 5) HW 1.70 - 2.18; HL 1.58 - 2.06; EL 0.40 - 0.48; SL 0.93 - 1.18; MSNW 1.35 - 1.54; MSNL 1.40 - 1.95; WL 2.56 - 3.34; SPL 0.00; PTH 0.38 - 0.53; PTL 0.51 - 0.65; PTW 0.64 - 0.79; PPL 0.38 - 0.50; PPW 0.56 - 0.71; LHT 1.08 - 1.42; CI 0.99 - 1.08; OI 0.23 - 0.26; SI 0.57 - 0.59; MSNI 0.79 - 1.02; SPI 0.00; PTHI 0.73 - 0.90; PTWI 1.21 - 1.26; PPI 1.28 - 1.74; LBI 2.22 - 2.36.

Description

( Fig. 13D - F ) Large to very large size (HW 1.70 - 2.18, WL 2.56 - 3.34). With worker characters, except as follows.

Masticatory margin of mandibles with five teeth; antennal scapes short, usually not surpassing level of lateral ocelli; eyes small (OI 0.23 - 0.26), situated at or slightly below midline of head in full-face view; head shape more or less quadrate (CI 0.99 - 1.08), posterior margin straight.

Mesoscutum in dorsal view usually longer than wide (MSNI 0.79 - 1.02); dorsal face of propodeum short, meeting posterior face at a right angle; propodeal spines or tubercules absent; petiole broadly flared, postpetiole merely impressed posteriorly; subpetiolar process absent.

Head sculpture aciculate to carinulate; otherwise aciculate to reticulate throughout; face usually with abundant, longer, erect setae and dense, short, erect to decumbent pubescence; mesonotum with dense, short, suberect pubescence, and interspersed longer, erect setae; petiole and postpetiole with dense short suberect to decumbent pilosity, and postpetiole with additional longer dorso-posterior setae; abdominal tergites and sternites four to seven with abundant erect pilosity and dense appressed pubescence. Colored black; wings with a brown hue.

Male

Measurements

(n = 3) HW 0.84 - 0.88; HL 0.68 - 0.71; EL 0.27 - 0.31; SL 0.17 - 0.18; MSNW 1.07 - 1.13; MSNL 0.96 - 1.09; WL 1.82 - 2.10; SPL 0.00; PTH 0.24 - 0.30; PTL 0.26 - 0.36; PTW 0.33 - 0.41; PPL 0.18 - 0.22; PPW 0.37 -

0.43; LHT 0.97 - 1.01; CI 1.22 - 1.24; OI 0.40 - 0.44; SI 0.25 - 0.27; MSNI 1.03 - 1.12; SPI 0.00; PTHI 0.82 - 0.94; PTWI 1.13 - 1.26; PPI 1.91 - 2.09; LBI 1.84 - 2.07.

Description

( Fig. 14A, C ) Large males (HW 0.84 - 0.88, WL 1.82 - 2.10).

Mandibles short and reduced, one minute apical tooth present; clypeus not much protruding; eyes fairly small (OI 0.40 - 0.44); midline of eyes situated well below midline of head, almost extending to clypeal margin; antennae 12-segmented; head wider than long (CI 1.22 - 1.24); in full-face view ocellar triangle situated below posterior head margin, elevated with respect to rest of face; occipital carinae very distinct, with a thin flange projecting backwards.

Mesoscutum in dorsal view as wide as or slightly wider than long (MSNI 1.03 - 1.12); scutellum in dorsal view broadly tapering from anterior to posterior end, dorsoposterior part rounded; metanotum protruding only slightly from below scutellum; dorsal face of propodeum short; propodeal spines absent; petiole in dorsal view oval, laterally rounded, in lateral view anteriorly greatly tapering; subpetiolar process absent; postpetiole fairly flat and short, lacking median impression.

Head sculpture rugulose-reticulate; mesosoma dorsally with very fine longitudinal carinulae; otherwise sculpture more or less reticulate to aciculate; dense, short, erect to decumbent pubescence covering head, meso- and metasoma, interspersed with a few longer, erect setae. Color black.

Distribution and biology

MADAGASCAR. Crematogaster mafybe sp. nov. is a high-elevation specialist mostly found throughout the rainforest and montane forests of the central and south-central highland region and northern Madagascar from 700 m to 2150 m in elevation ( Fig. 14B ). Interesting disjunct populations exist in western Madagascar in the isolated montane forests of Analavelona and RS Ambohijanahary. There are some records of this species from coastal littoral and dry forest in northern Madagascar (see Supplementary Material 1) at low elevations, but we suspect that this habitat is suboptimal for this species. Crematogaster mafybe sp. nov. co-occurs mostly with C. degeeri , C. alafara sp. nov. and C. malahelo sp. nov. in montane habitats, but is also found in sympatry with C. tricolor stat. rev., C. dentata stat. nov., C. maina sp. nov., C. ramamy sp. nov., C. lobata and C. sewellii at several locations. This species has been collected mostly from nests in dead branches and twigs above ground, and we thus assume that its preferred nesting sites are arboreal. In montane habitats, however, this species also nests in rotten logs on the ground and under stones.

Figures

Fig. 13. Crematogaster mafybe sp. nov., worker and queen. A-C. Worker (CASENT0317762). A. Fullface. B. Profile. C. Dorsal. D-F. Queen (CASENT0193464). D. Full-face. E. Profile F. Dorsal.

Fig. 14. Crematogaster mafybe sp. nov., male and distribution. A, C. Male (CASENT0193465). A. Fullface. C. Profile. B. Species distribution.