Dolichoderus magnipastor

Only sparse data are available for a series collected in Poring: very long, highly frequented trail system in the high canopy (collected at canopy walkway), obviously diurnal herdsmen with large colonies; associated with Doryphorococcus lentiginosus (Allomyrmococcini); peculiar mode of transport (riding on ant’s head or in between metathorax and front coxae. No biological data are available for other series. (Dill 2002)

Identification
Dill (2002) - A member of the Dolichoderus cuspidatus species group. Dolichoderus magnipastor is well defined by its coarse sculpturing of the head in connection with the presence of the slender spine- or cornicle-like appendages of the propodeum. Furthermore, magnipastor is the largest and most robust species of the Dolichoderus cuspidatus group. Regarding the development of spines (one pair on propodeum, none on mesonotum) and the emarginate petiolar scale, magnipastor is similar to the sympatric Dolichoderus coniger. In this character they morphologically link the unarmed species of the group on the one side with Dolichoderus brevithorax, cuspidatus, and Dolichoderus furcifer (two pairs of spines) on the other side. However, on the basis of the diagnostic characters given, magnipastor is easily distinguishable from coniger. The particular spatulate shape of the propodeal spines equals cuspidatus rather than coniger. Yet, there is some morphological resemblance to the Peninsular Malaysian population of the unarmed Dolichoderus tuberifer: the distinct areolate-rugose sculpturing, the strongly developed superoccipital pit, and the shape of the mesonotal hump. Since the available material stems from only five series, a sound assessment of the intraspecific variability is hardly possible.

Distribution
Northern Borneo.

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

Nomenclature

 *  magnipastor. Dolichoderus magnipastor Dill, 2002: 55, figs. III-17, III-66 (w.) BORNEO.

Worker
(Holotype in brackets): HL 1.52-1.84 [1.75]; HW 1.68-2.08 [1.94]; EL 0.31-0.42 [0.35]; SL 1.26-1.46 [1.29]; AL 2.20-2.66 [2.53]; PnW 1.06-1.37 [1.30]; ML 0.78-0.88 [0.82]; MW 0.56-0.73 [0.71]; PpL 0.98-1.14 [1.04]; PpW 0.82-1.00 [0.87]; PpH 1.01-1.22 [1.16]; PpSW 1.17-1.33 [1.25]; PtL 0.55-0.59 [0.55]; PtW 0.60-0.76 [0.70]; TL 5.53-7.70 [7.30]. Indices: CI 107-116 [111]; OI 17-20 [18]; SI 65-75 [67]; MI 117-129 [117]; PpSPpI 118- 149 [144]; (n = 33).

Head: Black, antennae black, tip of funiculus reddish- to yellowish-brown; densely reticulate-punctate (= micro-imbricate), this fine sculpturing partly superimposed by coarser, reticulate wrinkles that form irregularly rounded or ± oval pits (areolate-rugose, figs. III-66a-b), particularly between vertex and occiput, less distinctly so on frons and sides. Very finely pubescent; void of erect hairs. Head distinctly wider than long; rounded heart-shaped; occipital margin deeply emarginate; anterior of the occipital margin a very distinct, broad and deep median superoccipital pit (fig. III-66a), often an additional median pinprick-like or slit-like impression on vertex (position of anterior ocellus, fig. III -66b).

Alitrunk: Blackish-brown or black. Finely reticulate or punctate (= micro-imbricate); except for lateral and declivitous faces of propodeum, additionally with a coarse, irregularly areolate-rugose sculpturing. Finely pubescent; erect hairs sparse and restricted to sternites and coxae. Dorsal face of pronotum weakly convex, with a concave depression in each side; its lateral delimitation indistinct, rounded, not edged, “shoulders” indistinct. Anterior portion of mesonotum, in profile, forming a steeply ascending, bluntly coniform, medially impressed hump, the anterior face of which ascending distinctly steeper than the dorsal face of pronotum (fig. III-17b); posterior third of the mesonotal hump flattened. Dorsal face of propodeum, in profile, steeply and ± straightly ascending; its posterior corners expanded to a pair of slender, spines or comicles with ± spatulately flattened and broadened lips, which are pointing up and sidewards (fig. III-17e).

Petiole: Brownish-black; finely reticulate (= micro-imbricate) and pubescent. Dorsal margin of scale edged, either entire and straight or ± concavely emarginate (fig. III-17f).

Gaster: Finely reticulate; ± densely, golden-yellowish pubescent; particularly on tergites 2 and 3, pubescence merging in a median line; pilosity sparse and restricted to sternites and tip of gaster.

Type Material
Holotype worker, 2 paratype workers (BMNH), 2 paratype workers , 2 paratype workers , 3 paratype workers (FNMS), all from same series: Borneo, Sabah, Poring Hot Springs, Kinabalu NP, 6°04' N, 116°42' E, Canopy-Walkway, 30.v.1991 (M. Dill).

Etymology
Name derived from the Latin words “magnus” (great, large) and “pastor” (herdsman), referring to the fact that this species has the largest workers amongst all hitherto known herdsmen Dolichoderus, and also has very large colonies.

References based on Global Ant Biodiversity Informatics

 * Dill M. 2002. Taxonomy of the migrating herdsmen species of the genus Dolichoderus Lund, 1831, with remarks on the systematics of other southeast-Asian Dolichoderus. Pp. 17-113 in: Dill, M.; Williams, D. J.; Maschwitz, U. 2002. Herdsmen ants and their mealybug partners. Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft 557: 1-373.
 * Dill M., D.J. Williams, and U. Maschwitz. 2002. Herdsmen ants and their mealybug partners. Abh. senckenberg. naturforsch. Ges. 557: 1-373.
 * Pfeiffer M.; Mezger, D.; Hosoishi, S.; Bakhtiar, E. Y.; Kohout, R. J. 2011. The Formicidae of Borneo (Insecta: Hymenoptera): a preliminary species list. Asian Myrmecology 4:9-58
 * Yusah K. M., T. M. Fayle, G. Harris, and W. A. Foster. 2012. Optimizing diversity assesment protocols for high canopy ants in tropical rain forest. Biotropica 44(1): 73-81.