Camponotus (Tanaemyrmex) carinifer Viehmeyer, 1916

Camponotus (Tanaemyrmex) carinifer Viehmeyer, 1916 View in CoL stat. n.

Camponotus (Myrmoturba) tinctus var. carinifer Viehmeyer, 1916: 156 (s.q.)

Subspecies of Camponotus irritans View in CoL : Bolton, 1995: 91.

Material examined. Prince George’s Park Residences ( NUS), 1.292389, 103.778694 GoogleMaps , 15-22

Apr 2015, M.S. Foo & W. Wang leg., malaise trap, NUS0013, ZRC _ BDP0045404 View Materials ; same locality and collectors as previous, 29 Jul-5 Aug 2015, malaise trap, NUS0073, ZRC _ BDP0047331 View Materials ; same locality and collectors as previous, 23-30 Sep 2015, malaise trap, NUS0105, ZRC _ BDP0047294 View Materials ; Mandai mangroves, 17 Nov 1978, D.H. Murphy leg., ZRC _ HYM_0000881; same locality and collector as previous, 1975, ZRC _ HYM_0000882; Sungei Buloh Wetland Reserve , 14 Mar 2018, M.S. Foo leg., back mangrove, ZRC _ ENT00000911 View Materials .

Material not physically examined. Types – CASENT0910154 [cotype major of C. (Myrmoturba) tinctus var. carinifer ], ANTC32547 ( MHNG); FOCOL2391-2396 View Materials [queens and workers of C. tinctus var. carinifer ] ( ZMHB).

Literature. Types - Viehmeyer (1916); Overbeck (1924) [both as Camponotus (Myrmoturba) tinctus var. carinifer ]. Wang et al. (2018a) [identified as Camponotus irritans ].

Localities. Jurong Road; Mandai mangroves; Prince George’s Park Residences ( NUS); Sungei Buloh Wetland Reserve.

Habitat/Ecology. This species was found mainly in disturbed young or mature secondary forest fragments in semi-urban settings, close to man-made infrastructure. The type series was collected from a nest in a rotting dead tree trunk along a road. In mangroves, a colony was found nesting in a rotting branch of the mangrove plant Rhizophora .

Remarks. Prior to this study, C. carinifer was treated as a subspecies of Camponotus irritans ( Smith, 1857) . However, upon comparisons of type images and original descriptions, we believe C. carinifer is sufficiently distinct to be considered a separate species.

The original description of C. irritans was based on “normal” minor workers (not majors/soldiers), specifically a large worker (12.7 mm) and a smaller one (6.4 mm). We noted that the maximum size for non-major workers in C. irritans appears larger than in local minors of C. carinifer – the latter never exceeds 10 mm in total length. Further, even majors of C. carinifer are at most around 10 - 11mm in length, at least for specimens from Singapore.

Based on our observations, large minor workers of C. carinifer can be distinguished from those of C. irritans by the following ( C. irritans traits in parentheses): 1) mesosoma not elongate, in dorsal view pronotum as wide as head, rounded and not much narrowed anteriorly (mesosoma elongate and slender, pronotum narrower than head, distinctly tapered and narrowed anteriorly), 2) posterior margin of head very weakly and broadly convex in full face view (posterior margin of head strongly convex), 3) petiole in profile narrower and more squamiform, weakly tapered towards apex (petiole longer, strongly tapered towards apex), 4) apex of scape and most of antenna flagellum light yellowish-brown, reddish-brown at the tips (apex of scape and entire flagellum ferruginous).

Camponotus carinifer View in CoL is very similar to Camponotus tinctus ( Smith, 1858) View in CoL (nom. rev., see relevant species section below). In fact, the minor workers are almost indistinguishable from each other. The two species can still be differentiated based on major workers and queens. We discuss this in greater detail under Remarks for C. tinctus View in CoL .