Cladomyrma hewitti

All specimens of Cladomyrma hewitti, from just a few collections, are all from Sarawak.

Identification
Agosti et al. (1999) placed Cladomyrma species into two groups based on the shape of the queen's petiole, raised (an erect node or scale) or depressed (dorsally truncate and low). Cladomyrma hewitti belongs to the raised petiole group.

After examining the type again and remounting the queen, it became obvious that the extremely long head of the worker is correlated with a unique, long, parallel-sided head of the queen, and a nodiform petiole, which is not present in andrei or indeed any other species. In lateral view the queen head of the lectotype specimen is rather elongated, correlated with an exceptionally long alitrunk. In these respects the type thus differs from all other Cladomyrma species. None of the additional specimens has this elongated head or AL size. However, in the nontype specimens the character combinations of a long head, together with the raised petiole, make it most likely that they belong to the same species.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia.

Biology
Agosti et al. (1999) - The type specimen was collected in Bidi (SW of Kuching, near Bau), Sarawak, in the "swollen internodes of a shrub" (label information). Based on current knowledge, the shrub might be a representative of one of eight domatia-bearing Bornean Neonauclea species, the only host tree genus of Cladomyrma with distinct swollen internodes whose species locally grow as shrubs (the other Bornean hosts are either understory treelets or climbers). Indeed, new collections of this species were made only from domatia of two Neonauclea species. However, it cannot be excluded that the ‘‘shrub’’ may belong to Myrmeconauclea strigosa, a small rheophytic treelet or shrub with spontaneously opening domatia. This species, regularly colonized by a variety of facultative stem-nesting ant species (Maschwitz et al., 1989), was never found to be inhabited by Cladomyrma in Sabah and Sarawak (n > 50), but recent collections in Brunei revealed that colony-founding queens rarely colonize the domatia of Myrmeconauclea strigosa (C. Brouat and D. McKey, personal commun.). It is not known if neighboring Neonauclea trees, which often grow in Myrmeconauclea habitat, are the source plants of these foundress queens. A second trip to the collecting site revealed that Neonauclea, inhabited by Cladomyrma ants, grow in close vicinity to Myrmeconauclea strigosa (D. McKey, personal commun.). We suspect that only a very low frequency of Cladomyrma queens occupy the latter plant species, presumably due to high intraspecific competition for regular host plants in the vicinity. Mature colonies or alates of Cladomyrma were not found in Myrmeconauclea strigosa. Nevertheless, this phenomenon needs to be studied in detail.

Nomenclature

 *  hewitti. Aphomomyrmex hewitti Wheeler, W.M. 1910c: 132, fig. 1 (s.q.) BORNEO. Combination in Cladomyrma: Wheeler, W.M. 1920: 53. Agosti, Moog & Maschwitz, 1999: 20 (w.). Junior synonym of andrei: Agosti, 1991: 303. Revived from synonymy: Agosti, Moog & Maschwitz, 1999: 20.

Worker
Agosti et al. (1999) - Major: AL 0.98–1.23, HL 0.95–1.26, HW 0.84–1.06, EL 0.16–0.23, SL 0.44–0.52, CI 86–90, EI 19–23, SI 47–55 (n = 8).

Elongate head with subparallel sides; clypeus, in lateral view, rounded; large metapleural gland orifice; body dark brown with gaster and head distinctly darker; genae lighter brown; body surface shining; gastral pubescence sparse, widely set, so that pubescence hairs do not overlap; medium to large sized ants.

Minor worker. AL 0.70–0.90, HL 0.66–0.84, HW 0.58–0.74, EL 0.13–0.18, SL 0.32–0.45, CI 87–88, EI 22–25, SI 55–61 (n = 4).

Body color dark brown with gaster and head darker; metapleural gland orifice large; medium sized ant; gastral pubescence on tergites widely set and short; hairs not longer than the space in-between them.

Queen
Agosti et al. (1999) - AL 2.32–2.92, HL 1.60–1.80, HW 1.32–1.36, EL 0.52–0.60, SL 0.80–0.92, CI 77–83, EI 37–45, SI 60–68 (n = 6). Lectotype: Soldier(?) AL 1.18, HL 1.22, HW 1.06, SL 0.50, EL 0.22, CI 87, EI 21, SI 47. Queen from same series as lectotype: AL 2.92, HL 1.8, HW 1.32, EL 0.60, SL 0.84, CI 73, EI 45, SI 54.

Clypeus slightly angulate with anterior face straight; head long in full frontal view, with parallel sides; genae same color as reminder of head; dorsal part of katepisternum punctulate and with thin pubescence; metapleural gland orifice large and open; petiole in lateral view high, dorsally truncated with the posterior face gently sloped; whole body covered with long, erect hairs; gaster with short, widely set subdecumbent pubescence; gaster surface with silky shine; head and alitrunk (dark) brown, gaster with at least posterior parts of tergites darker; large body size.