Austroplebeia cincta (Mocsáry), Mocsary

Dollin, Anne E., Dollin, Leslie J. & Rasmussen, Claus, 2015, Australian and New Guinean Stingless Bees of the Genus Austroplebeia Moure (Hymenoptera: Apidae) — a revision, Zootaxa 4047 (1), pp. 1-73 : 25-30

Austroplebeia cincta (Mocsáry)

( Figures 1 , 2 , 5 , 9 , 11 , 13–17 , 19–25 , 28–31 , 33 )

Trigona cincta Mocsáry in Friese 1898: 431.

Austroplebeia cincta — Moure 1961: 197; Michener 1990: 97, 110, 133, 134. Trigona (Plebeia) cincta — Michener 1965: 230.

Diagnosis. In workers and males, frons and mesepisternum lacking plumose hair or nearly so ( Figs 22 a–b, 23a, 25 a, c), paraocular area with cream to yellow maculation along orbital margins extending well above antennal sockets (Face Grades 9–14, 20–21, Figs 1 , 2 , 22 a–b, 23a), head width <1.65 mm ( Fig. 14 ). In workers, metepisternum with a large yellow-brown to yellow maculation ( Fig. 25 a). In males, maculation absent on dorsal scutellum (Thorax Grade 18, Figs 5 , 25 c). Distribution NG and QLD ( Fig. 28 a).

Description. As in general Austroplebeia description, except for the following characters.

Worker. Body NG: 3.3–4.2 mm, QLD: 3.0– 3.5 mm. Forewing (including tegula) NG: 3.6–4.0 mm, QLD: 3.4– 3.7 mm. All other measurements are listed in Table 2. (Structural data were not collected from BMNH and NRIPG specimens.)

Structure. Head width NG: 1.52–1.64 mm (eyes of bees with lowest scores alcohol-affected and possibly slightly collapsed), QLD: 1.47–1.59 mm. Head width 1.2x head length. Interocellar distance NG: 1.3–1.4x, QLD: 1.4–1.9x ocellorbital distance. Clypeus length 0.5x width. Malar area 0.2–0.3x basal mandibular width. Mandible preapical teeth more closely spaced than in other species ( Fig. 17 d), distance between apices of two preapical teeth (relative to total mandible length) in QLD A. cincta 0.6–0.8x distance in other species. Scape length 0.7–0.8x alveolus–lateral ocellus distance.

Scutellum length 0.4x width. Wing venation similar to that shown in Fig. 18 . First transverse cubital vein vestige (up to 75 Μm) present in NG: 65%, QLD: 10% of wings examined and slight trace in NG: 32%, QLD: 65% (NG: n=34, QLD: n=51). Vein M of forewing extends slightly beyond position of anterior end of first recurrent vein in NG: 71%, QLD: 67% of wings examined, terminal segment straight or with only a slight bend (NG: n=28, QLD: n=48). Cell second Cu of forewing completely indicated by pigmented vein traces in NG: 100%, QLD: 97% of wings examined (NG: n=30, QLD: n=33). Hamuli per wing 5 to 6. HBW narrow ( Figs 11 , 19 h), NG: 0.28–0.33 mm, QLD: 0.27–0.32 mm.

Sting rudiments. Gonostyli shoulder width narrow, NG: 0.11 mm, QLD: 0.08–0.11 mm. Apex of sting stylet often angular or with a narrowly rounded protrusion. Sting lancet length short, NG: 0.27 mm, QLD: 0.27–0.30 mm ( Figs 15 , 16 a–b).

Colour of NG specimens. Face markings usually Grades 13–14, sometimes 12 ( Fig. 1 ). Thorax markings Grade 16, sometimes 15 or 17 ( Fig. 5 ),

Other areas with yellow markings (sometimes dull yellow or cream): ventral scape, upper edge of pronotal collar except medially, pronotal lobe, metepisternum, all trochanters, femur I, tibia I and basitarsus I.

Unmarked areas of clypeus ranging dark brown to red-brown. Labrum cream, sometimes yellow or yellowbrown. Mandible ranging orange-brown to yellow medially ( Fig. 9 ). Scape dark brown or red-brown dorsally, yellow ventrally. Flagellum red-brown or brown. Tegula yellow-brown or orange brown, sometimes with a cream spot. Yellow marking covering ca. 30–50% of metepisternum. Basal and medial terga ranging dark brown to brown. Apical terga dark brown to yellow-brown ( Fig. 9 ). Sterna dark brown to yellow brown. Unmarked areas of tibia I orange-brown. Trochanters cream to orange-brown. Femur I red-brown with a distal yellow to yellow-brown spot. Tibia I and basitarsus I yellow to orange-brown. Other femora, tibiae and basitarsi black to red-brown, sometimes with a dull cream distal spot on tibia II. Mediotarsus orange-brown to yellow-brown.

Colour of QLD specimens. As for NG A. cincta workers, except for the following characters:

Face markings ranging Grades 9–11 ( Fig. 1 ). Thorax markings usually Grade 16 or 15, rarely 17 ( Fig. 5 ),

Unmarked areas of clypeus ranging dark brown to brown. Mandible ranging red-brown to cream medially ( Fig. 9 ). Flagellum dark brown.

Tegula yellow-brown, sometimes red-brown to brown. Yellow marking covering ca. 40–60% of metepisternum ( Fig. 25 ). Basal and medial terga ranging dark brown to yellow-brown. Apical terga orange-brown to yellow-brown ( Fig. 9 ). Sterna orange-brown to yellow-brown. Trochanters cream to yellow-brown. Femur I brown or yellow-brown, with a distal yellow-brown to yellow spot. Tibia I and basitarsus I yellow to yellowbrown. Other femora, tibiae and basitarsi black to red-brown. Mediotarsus brown or yellow-brown.

Pilosity. Frons, clypeus and supraclypeal area with numerous appressed short (ca. 25 Μm) golden simple hairs, lacking plumose hair. Paraocular area and supraantennal area with short appressed golden plumose hairs ( Figs 22 a–b). Vertex with long erect golden bristles (NG: 50–125 Μm, QLD: 50–100 Μm). Malar space evenly covered with short fine appressed hair. Gena with short golden appressed simple hair.

Scutum with numerous fine short (ca. 25 Μm) golden simple hairs, sparse longer (75–100 Μm) hairs restricted to lateral margins. Scutellum with fine short golden simple hairs and a fringe of long (NG: 50–225 Μm, QLD: 50– 175 Μm) golden bristles. Pronotal lobe covered with short, very fine, dense pale hair. Mesepisternum with semierect pale simple hairs, gradually longer (up to 175 Μm) ventrally ( Fig. 25 a). Hypoepimeral area and metepisternum with pale simple hair, some plumose hair on posterior dorsal metepisternum. Propodeal sides with dense whitish plumose hair. Propodeal triangle almost hairless.T1 to T6 apically with pale golden simple hairs, becoming denser and longer on posterior terga, minute on T1 and up to 125 Μm on T6. Sterna with long erect pale simple hairs, gently curved or straight apically.

Coxae II and III and all trochanters with long simple pale hairs, hooked apically. Coxa I and all femora with shorter straight hairs. In mature, fully coloured specimens: anterior and posterior corbicular fringes with simple pale hairs, penicillum and rastellum bristles pale golden, basitarsus III inner surface evenly covered with coarse pale golden bristles.

Male (known only from QLD). Body 3.8–4.1 mm. Forewing (including tegula) 3.5–3.7 mm All other measurements are listed in Table 5 .

Structure. Head width 1.53–1.59 mm. Interocellar distance 2.5–2.8x ocellorbital distance. Clypeus length 0.6x width. Mandible preapical tooth acutely pointed and stronger than in other Austroplebeia species ( Fig. 17 i). Scape length 0.6–0.7x alveolus–lateral ocellus distance. Flagellum relatively shorter than in other species, flagellum length 3.6–3.9x scape length. Hamuli per wing 5. HBW narrow, 0.20–0.22 mm. HTW narrow, 0.35–0.38 mm ( Fig. 13 ). HTL short, 1.05–1.08 mm ( Fig. 14 ).

Terminalia and genitalia. S3 and S4 pregradular area wider than in other species. S5 gradulus transverse, with pregradular area wider than in other species, apical margin with broad protruding lobes. S6 with median body narrow and parallel sided. S7 triangular and apical margin gently pointed ( Figs 20 a, g, k, p). Gonostylus gently curved. Base of penis valve relatively narrow and long, and more tapering than in other species ( Fig. 21 a).

Colour. Face markings usually Grade 20, sometimes 21 ( Fig. 2 ). Thorax markings Grade 18 ( Fig. 5 ), narrow maculation on posterior rim of scutellum varies from faint yellow-brown to solid cream.

Other areas with yellow markings (sometimes dull yellow or cream): ventral scape, mandible, pronotal lobe, distal femur I, tibia I and all basitarsi; usually labrum and trochanters; sometimes apical sterna, and tibiae II and III. Note that metepisternum and dorsal surface of scutellum lack yellow markings.

Scape dark brown dorsally, yellow ventrally. Flagellum black to dark brown. Tegula red-brown. Metanotum black or dark brown. Basal and medial terga ranging black to brown. Apical terga red-brown or yellow-brown ( Fig. 9 ). Sterna ranging dark brown to yellow. Unmarked areas of tibiae: tibia I yellow-brown or brown, tibia II dark brown or red-brown, tibia III dark brown to yellow brown.

Pilosity. Frons, clypeus, supraclypeal and supraantennal areas with numerous appressed short golden simple hairs, admixed with longer (ca. 125 Μm) erect simple hairs and sparse weakly plumose hairs on the frons ( Fig. 23 a). Paraocular area with denser coarse golden simple hairs and/or fine plumose hair. Vertex with long erect pale gold bristles (100–225 Μm). Malar space evenly covered with short fine appressed hair. Gena with short golden appressed simple hair.

Scutum with numerous fine short (ca. 25 Μm) golden simple hairs, up to 125 Μm on lateral margins. Scutellum with fine short golden simple hairs and a fringe of long (up to 275 Μm) pale gold bristles. Mesepisternum with semi-erect pale simple hairs, gradually longer (up to 175 Μm) ventrally ( Fig. 25 c). Pronotal lobe covered with short, very fine, dense pale hair. Hypoepimeral area and metepisternum with pale simple hair. Propodeal sides with dense whitish simple and plumose hair. T1 to T7 apically with pale golden simple hairs, becoming denser and longer on posterior terga, minute on T1 and up to 250 Μm on T7.

All coxae, all trochanters and basal femur I with long straight simple pale hairs. In mature, fully coloured specimens: basitarsus III inner surface bristles golden.

Surface sculpture. Face and scutum shiny with numerous fine punctures, spacing 1– 2 x puncture diameter. Terga shiny. Propodeal triangle, areas of terga especially apical margins and tibia III with fine reticulate sculpturing.

Queen (known only from QLD). Body 5.0 mm. Forewing (including tegula) 3.9 mm.

Structure. HBW 0.20–0.23 mm.

Colour. Clypeus and supraclypeal area yellow or yellow brown, maculation extending into medial supraantennal area. Paraocular area maculation extends around entire orbit of eye and onto ventral gena ( Fig. 24 a). Thorax marking Grade 17. Metepisternum maculation present.

Pilosity. Clypeus with very fine sparse simple hair. Scutellum bristles pale to golden and up to 425 Μm. T1–T5 with sparse fine short hairs, sparse longer (up to 150 Μm) coarse bristles on lateral surfaces of T3–T5. T6 with short dense hair and an apical fringe of long (up to 250 Μm) simple hairs. Basitarsus III inner surface bristles pale gold to golden.

Material examined. Holotype. ( HNHM, worker), labelled as follows: “Friedrich- / Wilh.-hafen”, “N. Guinea / Biró 96”, “ HOLOTYPE / Trigona cincta / Mocsáry, 1898 ”

Provenance of holotype: Lajos Biró (1856–1931) went to New Guinea to collect zoological and ethnographical objects between 1896 and 1901. The collection of Biró was sent to the museum in Budapest where the curator, Alexander (or Sándor) Mocsáry, described this specimen as Trigona cincta in a paper by Friese (1898) on Australian and New Guinean stingless bees. The holotype was collected near Friedrich Wilhelmshafen, now Madang, Papua New Guinea, in 1896.

Other worker and male specimens examined. Papua New Guinea: Samples collected from flowers or traps: Aitape district, Wapei, 2000ft, Feb 1936, AJ Marshall, AMS, 15 workers; no date, AJ Marshall, AMS, 3 workers; East Sepik District, Kairiru Island, 22–24 Oct 1974, J. Pippet, NRIPG, 1 worker; Madang district, Wanuma, 600–720m, Aug 1968, NLH Krauss, 1 worker; Wum, Upper Jimi Valley, 840m, 16 Jul 1955, JL Gressitt, 1 worker; Kumur, Upper Jimi Valley, 1000m, 13 Jul 1955, JL Gressitt, 1 worker; Aiyura, 26 Jun 1960, JH Barrett, NRIPG, 6 workers; Lae, Mar 1945, L. Le G. Troughton, AMS, 2 workers; Bulolo, 28 Jun 1950, ANIC, 1 worker; Jun 1950, H Faddy, AMS, 2 workers; Bulolo, Watut R, Morobe, 1300m, 21 Dec 1973, T Okazawa, 2 workers; Bulolo Hlds, Crooked Creek, 20 Apr 1963, JH Barrett, NRIPG, 1 worker; Mafulu, 4000ft, Dec 1933, LE Cheesman, BMNH,> 10 workers; Kakoda, 200ft, 1933, LE Cheesman, BMNH, 1 worker; Mt Lamington, all by CT McNamara: 1927, BMNH, 1 worker; May 1927, AMS, 2 workers; Jul 1927, AMS, 4 workers; Sep 1929, AMS, 1 worker; no date, AMS, 3 workers; Port Moresby, Konedobu, 1954, JJH Szent-Ivany, BMNH, 2 workers; Port Moresby P., nest in tree, 3 Jan 1956, JH Barrett, NRIPG, 1 worker; Port Moresby, Brown River, 30 May 1978, J Stibick, NRIPG, 1 worker. Two additional localities reported in Michener (1961): Kerema, Kapagere.

Indonesia, Province of Papua: Samples collected from flowers or traps: Cyclops Mts, Sabron Camp 2, May 1936, LE Cheesman, BMNH,> 10 workers; Njau-limon, S Mt Bougainville, 1936, BMNH, 1 worker; Central Mountains, Mulik R 10k E Archbold Lake, 1050m, 25 Nov & 3–5 Dec 1961, S & L Quate, 2 workers.

Australia, Queensland: Nest samples: 5k S Rossville, Jun 2010 (by L. Roberts: Nest D1, 6 workers; Nest D2, 20 workers; Nest D3, 20 workers; Nest D4, 6 workers; Nest D5, 20 workers; Nest D6, 20 workers), Jan 2011 (by L. Roberts: Nest D7, 17 workers; Nest D8, 20 workers; Nest D9, 20 workers; Nest D10, 20 workers; Nest D11, 5 workers), Nov 2012 (by AED & LJD: Nest D10, 20 workers,> 20 males; Nest D13, 18 workers; Nest D14, 20 workers,> 20 males; Nest D15, 2 workers; Nest D16, 8 workers). —Samples collected from flowers or traps: 5k S Rossville, 17–19 Oct 1980, JC Cardale, ANIC, 6 workers; Kuranda, Feb 1921, FP Dodd, SAMA, 2 workers; 17 May 1980, ID Naumann & JC Cardale, ANIC, 1 worker; Nov 2012, AED & LJD, 21 workers; Cairns district, FP Dodd, SAMA, 1 worker.

Queen specimens examined. Nest samples collected by AED & LJD, 2 queens: Queensland: 5k S Rossville, Nov 2012 (Nest D10, 1 gravid, 1 virgin).

Remarks. The holotype specimen of A. cincta agrees well in structure ( Fig. 11 , Table 2), pilosity and colouration (Face Grade 13, Thorax Grade 16, Figs 1 , 5 ) with more recent A. cincta populations in New Guinea. The maculations on the paraocular area, dorsal thorax and metepisternum are discoloured but still clearly visible. Its type locality, Madang, Papua New Guinea, is well within the current range of the species ( Fig. 28 a).

Austroplebeia cincta is the only Austroplebeia species that has been recorded outside of Australia. Museum collections indicated that it was distributed in coastal and mountainous areas of Papua New Guinea as well as the Indonesian province of Papua ( Fig. 28 a). Unfortunately these museum collections were limited to individual worker bees collected from flowers. No male or queen specimens of A. cincta from New Guinea have been located. The nest structure of A. cincta in New Guinea that was reported by Michener (1961) closely resembled that of the QLD population in Australia (Dollin 2013).

Within Australia, A. cincta has only been confirmed from two localities in QLD. Nine collections of Austroplebeia were surveyed without success in a search for further Australian A. cincta populations: BMNH, AMS, ANIC, NMV, WAM and Biosecurity Queensland, Portsmith, QLD (by AED); Queensland Museum, Brisbane, QLD (by T. Heard); and DAFF Centre for Tropical Agriculture, Mareeba, QLD, and Department of Agriculture, Fisheries and Forestry (formerly AQIS), Cairns Airport, QLD (by W. Forno).

Eric Mjöberg collected stingless bees in WA during his expedition in 1910–1911. The bees' collection locality was given as 'Kimberley District', but the expedition only visited localities in the southern Kimberley within 220 km of Derby, WA ( Mjöberg 2012). Friese (1917) identified 23 of Mjöberg's worker specimens as Trigona cincta . However, one of the specimens examined by Friese, currently in the Natural History Museum, University of Kansas, does not belong to A. cincta (CD Michener, pers. comm. to AED, 2008; Dollin 2013). This Kimberley specimen has now been identified as A. essingtoni (VH Gonzalez, pers. comm., 2015).

Austroplebeia cincta workers from QLD closely resembled those from NG, though the QLD workers tended to be slightly smaller ( Fig. 11 ) and darker. Also in specimens with less developed clypeus maculations, QLD workers tended to have medial markings whilst NG workers tended to have apical bands (Grades 9–14, Fig. 1 ).

The QLD A. cincta males were surprisingly dark. In other Austroplebeia species, the males had much more extensive colour maculations than the workers (compare Figs 7 and 8 , 25 b and d). Austroplebeia cincta males had a scutellum that was almost completely black and they lacked the maculations on the pronotal collar and tegula common in other Austroplebeia males. They also lacked the metepisternum maculation seen in A. cincta workers (compare Figs 25 a and c).

Wing venation. In his description of the genus Austroplebeia, Michener (1990) suggested that vestiges of the first transverse cubital vein ( Figs 18 a–c) were primarily found in A. cincta . This is generally true, but the much larger sample sizes of the present study reveal a more complex pattern. This characteristic was quite variable. In a number of workers, a vestige was even present in one wing and absent in the other.

The highest proportion (65%) of workers with this characteristic was seen in NG A. cincta . In QLD A. cincta , only 10% of specimens had this vein vestige, whilst 65% had only a thickening of vein M at this position. In other Austroplebeia species, vestiges of the first transverse cubital vein were seen in 11–38% of specimens. Vestiges up to 75 Μm long were seen in in NG A. cincta . However, vestiges of similar or slightly greater length (up to 90 Μm) were seen in some specimens of A. australis ( Fig. 18 c) and A. magna sp. nov.

In his notes on Couplet 1 after the 'Key to the recent genera of Meliponinae', Michener (1990) also notes that traces of second cell Cu ( Fig. 18 a) are evident in A. cincta but not in some other species. In the present study, second cell Cu was indicated by pigmented vein traces in virtually all A. cincta workers examined. However, this was also true of both the Eastern and Western Colour Morphs of A. australis . In contrast, almost all A. essingtoni workers had cell second Cu undefined or defined by unpigmented vein traces.

Fortunately this variability in Austroplebeia wing vein characteristics does not cause a problem with Michener's key in this paper, as he designed it so Austroplebeia can run both ways from Couplet 1.

Sting stylet. A short, narrowly rounded or pointed protrusion from the apex of the worker sting stylet was seen in some specimens of A. cincta , A. essingtoni , A. australis Central Colour Morph, A. cassiae and A. magna sp. nov. ( Figs 16 b, g, h). They were not as long as those seen in specimens of African Meliponula Cockerell illustrated in Michener (1990) Figs 43–46. However, their existence may add to the evidence for the relationship between Austroplebeia and the African genera ( Michener 2007, Rasmussen & Cameron 2007, 2010).

A. cincta A. essingtoni

Holotype Other workers (NG) Other workers (QLD) Holotype Paratype Other workers

VAR* Mean (N) SD Mean (N) SD Mean (N) SD 1 4.05 3.84 (8) 0.18 3.38 (14) 0.08 – 3.80 3.50 0.17 2 1.54 1.60 (9) 0.03 1.54 0.03 – 1.56 1.53 (16) 0.05 3 1.38 1.36 0.03 1.30 (13) 0.02 – 1.28 1.27 0.04 4 1.08 1.10 0.03 1.04 (13) 0.03 – 1.04 1.03 0.04 5 0.94 0.97 0.02 0.94 0.01 – 0.94 0.95 0.02 6 1.08 1.09 (9) 0.02 1.04 0.02 – 1.06 1.04 0.03 7 0.86 0.88 (9) 0.03 0.84 (13) 0.02 – 0.82 0.82 0.02 8 0.13 0.14 0.01 0.13 0.01 – 0.14 0.14 0.01 9 0.31 0.31 0.01 0.34 0.01 – 0.36 0.37 0.03 10 0.21 0.22 (9) 0.01 0.20 0.02 – 0.17 0.19 0.01 11 0.16 0.16 0.02 0.17 0.01 – 0.20 0.20 0.01 12 0.75 0.71 0.04 0.69 (13) 0.03 – 0.69 0.66 0.02 13 0.15 0.15 0.01 0.15 0.01 – 0.14 0.15 0.01 14 0.39 0.37 0.02 0.35 (13) 0.01 – 0.35 0.33 0.02

......continued on the next page A. cincta A. essingtoni

Holotype Other workers (NG) Other workers (QLD) Holotype Paratype Other workers VAR* Mean (N) SD Mean (N) SD Mean (N) SD *Variables: 1) total length of body; 2) head width1 ( Fig. 14 ); 3) head length1; 4) compound eye length1; 5) upper interorbital distance1; 6) maximum interorbital distance; 7) lower interorbital distance1; 8) median ocellus diameter; 9) interocellar distance (distance between lateral ocelli)1; 10) ocellorbital (or ocellocular) distance1; 11) interalveolar distance1; 12) alveolus–lateral ocellus distance; 13) alveolus diameter; 14) clypeus length1; 15) clypeus maximum width; 16) clypeocellar distance (distance between upper margin of clypeus and margin of median ocellus); 17) malar area length (minimum); 18) mandible basal width; 19) flagellum length; 20) scape length (excluding basal joint); 21) scape width (mid); 22) pedicel length; 23) 1st flagellomere length; 24) 1st flagellomere width; 25) 2nd flagellomere length ( Fig. 17 a); 26) 2nd flagellomere width; 27) 3rd flagellomere length; 28) 3rd flagellomere width; 29) scutum length; 30) scutum width (distance between tegulae); 31) scutellum maximum length; 32) scutellum maximum width; 33) forewing length without tegula ( Fig. 18 e); 34) forewing length including tegula; 35) forewing width ( Fig. 18 e); 36) wing diagonal ( Fig. 18 e); 37) 1st abscissa of M length ( Fig. 18 e); 38) 1st abscissa of Cu length ( Fig. 18 e); 39) number of hamuli ( Fig. 18 d); 40) tibia III length (HTL, Fig. 14 ); 41) tibia III width (HTW, Figs 11 , 13 ); 42) basitarsus III width (HBW, Figs 11 , 13 ). 1. Method for taking measurement shown in Fig. 10–3 of Michener (2007).

Other than the types, the following worker specimens were measured. NG A. cincta , N=10 unless otherwise stated, from flower samples in Papua New Guinea: Wapei (1x), Wum (1x), Kumur (1x), Wanuma (1x), Bulolo (3x), Mt Lamington (1x); and in the Indonesian province of Papua: Mulik River (2x). QLD A. cincta , N=15 unless otherwise stated, from nests D10 (4x), D14 (4x), and from flower samples collected at Kuranda, QLD, DS-15 (4x), SAMA collection (3x). A. essingtoni , N=17 unless otherwise stated, from nests N15 (4x), W9 (5x), W12(4x), W25 (4x).

Figures

FIGURE 1. Face colour marking grades used to classify Austroplebeia workers. In many specimens, these cuticle markings may be obscured by hair on the clypeus and paraocular area. Visualisation of these markings can be improved by tilting the bee's head back and viewing the face obliquely.

FIGURE 2. Face colour marking grades used to classify Austroplebeia males.

FIGURE 5. Thorax colour marking grades used to classify workers and males of Austroplebeia.

FIGURE 7. Variation in worker thorax colour grades observed within all Austroplebeia taxa except A. cincta. Data show 2503 workers from 158 colonies, in addition to 59 workers from 15 flower samples of A. australis – Western Colour Morph. Colour grades are as illustrated in Fig. 5.

FIGURE 8. Variation in male thorax colour grades observed within all Austroplebeia taxa except A. cincta and A. australis – Western Colour Morph. Data show 196 males from 38 colonies. Colour grades are as illustrated in Fig. 5.

FIGURE 9. Variation in colour of the clypeus, mandible (middle part) and apical terga in workers and males of all Austroplebeia taxa. (No males are known in A. cincta NG and A. australis – Western Colour Morph.) Data are based on 120 workers and 62 males.

FIGURE 10. Ratio of head width and extent of thorax colour marking in workers of all Austroplebeia taxa except A. cincta. Data from 121 colonies are shown, in addition to five flower samples from A. australis – Western Colour Morph and one A. australis flower sample with mixed Western / Central characteristics. Data points are averages from 10 – 49 workers per colony, or 5 – 12 workers per flower sample. Data from eight individual type specimens are also shown. The T. symei and T. ornata types, in which the eyes are collapsed preventing accurate head width measurement, are not shown. The T. essingtoni holotype has a missing head, so data from the paratype are shown. 1. Colony F 31 from the northern tip of Cape York Peninsula, QLD, which has characteristics similar to A. australis – Eastern Colour Morph despite its geographic isolation. Names given in brackets in the legend are groups in our Halcroft et al. (2015) preliminary analysis.

FIGURE 11. Ratio of tibia III width and basitarsus III width in workers of all Austroplebeia taxa. Data from 173 colonies are shown, in addition to 26 flower samples: A. australis – Western Colour Morph (14 x), A. australis with mixed Western / Central characteristics (4 x) and NG A. cincta (8 x). Data points are averages from 2 – 4 workers per colony, or 1 – 12 workers per flower sample. Data from 12 individual type specimens are also shown. 1. Colony F 31 from the northern tip of Cape York Peninsula, QLD, which has characteristics similar to A. australis – Eastern Colour Morph despite its geographic isolation. Names given in brackets in the legend are groups in our Halcroft et al. (2015) preliminary analysis.

FIGURE 13. Ratio of tibia III width and basitarsus III width in males of all Austroplebeia species. Data points are averages from 2 – 3 males per colony. Data from the male paratypes of A. magna sp. nov. are also shown. Names given in brackets in the legend are groups in our Halcroft et al. (2015) preliminary analysis.

FIGURE 14. Ratio of head width and tibia III length in males of all Austroplebeia species. Data points are averages from 2 – 3 males per colony. Data from the male paratypes of A. magna sp. nov. are also shown. Names given in brackets in the legend are groups in our Halcroft et al. (2015) preliminary analysis.

FIGURE 15. Worker sting rudiments metric data: ratio of maximum length of sting lancet (A) and shoulder width of gonostyli (B) in all Austroplebeia taxa. Data points are averages for 1 – 3 workers per nest or flower sample. 1. The geographically isolated colony, F 31, from the northern tip of Cape York Peninsula, QLD, which has colouring and HTW / HBW similar to A. australis – Eastern Colour Morph. 2. Colonies C 58 and D 55 from the ‘ intermediate’ group of Halcroft et al. (2015) which are consistent with A. australis – Eastern Colour Morph in this analysis. 3. CS- 8 workers, with Grade 4 Thorax Colour Markings, collected from flowers in the MacDonnell Ranges, NT. They are consistent with A. australis – Central Colour Morph in this analysis, despite their relatively dark colouration. 4. GS- 10 workers collected from flowers on the far western edge of the A. cassiae range. 5. NS- 7 workers collected from flowers on the far eastern edge of the A. magna sp. nov. range. Names given in brackets in the legend are groups in our Halcroft et al. (2015) preliminary analysis.

FIGURE 16. Austroplebeia worker sting rudiments: a, A. cincta NG; b. A. cincta QLD; c, A. essingtoni; d, A. australis – Eastern Colour Morph; e, A. australis – Central Colour Morph; f, A. australis – Western Colour Morph; g, A. cassiae; h, A. magna sp. nov. All drawn to same scale. Abbreviations: Gon—gonostylus; Sty—sting stylet (bulb); Lan—sting lancet (first valvula or first ramus).

FIGURE 17. Austroplebeia antennae, mandibles and labial palpi. Figs a – c. Antenna (basal part) of A. essingtoni: a, worker; b, male; c, queen. Figs d – h. Left mandible of worker: d, A. cincta QLD; e, A. essingtoni; f, A. australis; g, A. cassiae; h, A. magna sp. nov. Figs i – m. Left mandible of male: i, A. cincta QLD; j, A. essingtoni; k, A. australis; l, A. cassiae; m, A. magna sp. nov. Fig. n. Left mandible of A. australis queen. Figs a – n drawn to same scale. Figs o – q. Labial palpus of worker (mesal margins uppermost, small hairs omitted): o, A. cincta; p, A. cassiae; q, A. magna sp. nov. Figs o – q drawn to same scale. Abbreviations: F 1 — first flagellomere; F 2 — second flagellomere; F 3 — third flagellomere; F 2 L—second flagellomere length (showing how this measurement was made).

FIGURE 18. Austroplebeia wings. Dotted lines indicate pigmented vein traces. Figs a – c. Forewings, showing variation observed in the vestige of the first transverse cubital vein: a, A. magna sp. nov. forewing with a short vein vestige; b, Detail of an A. australis – Eastern Colour Morph forewing with a thickening of vein M at this position; c, Detail of an A. australis – Eastern Colour Morph forewing with a long vein vestige. Fig. d. Hindwing of A. magna sp. nov. Fig. e. Diagram of a forewing showing how the following measurements were made: (1) forewing length without tegula; (2) forewing width; (3) wing diagonal (Sakagami 1978); (4) 1 st abscissa of M length; (5) 1 st abscissa of Cu length. Figs a – d drawn to same scale: scale bar = 0.25 mm. Abbreviations: M—vein M; 1 st R—first recurrent vein; 2 nd Cu—second cubital cell; Ham—hamuli.

FIGURE 19. Austroplebeia legs. Figs a – b. Worker tibia III and basitarsus III of A. australis – Central Colour Morph: a, inner surface; b, outer surface. Fig. c. Cross-sectional view of A. australis worker tibia III, inner surface uppermost. Fig. d. Worker leg II of A. australis – Eastern Colour Morph, showing mesotibial spur near junction of tibia and basitarsus. Figs e – f. Male tibia III and basitarsus III of A. australis – Central Colour Morph: e, inner surface; f, outer surface. Fig. g. Queen tibia III and basitarsus III of A. australis – Central Colour Morph, outer surface. Fig. h. Variation in size of worker basitarsus III (shaded segment), all drawn to same scale: A. cincta QLD is shown on the left, then remaining species are shown in order of increasing basitarsus III width. Abbreviations: Kei—keirotrichia; Pos—posterior corbicular fringe; Ant—anterior corbicular fringe; Rasrastellum; Cor—corbicula; Pen—pencillum.

FIGURE 20. Austroplebeia male sterna and terga, shown in ventral view except for Fig. r. Figs a – f. S 4: a, A. cincta; b, A. essingtoni; c, A. australis; d – e, A. cassiae showing variation in position of gradulus; f, A. magna sp. nov. Figs g – j. S 5: g, A. cincta; h, A. essingtoni, arrow indicates protruding apical lobe; i, A. australis; j, A. cassiae. Figs k – o. S 6: k, A. cincta; l, A. essingtoni; m, A. australis; n, A. cassiae; o, A. magna sp. nov. Figs p – q. S 7: p, A. cincta; q, A. australis. Fig. r. T 7 of A. cassiae, dorsal view. Figs a – f, scale bar = 0.5 mm; figs g – r, scale bar = 0.33 mm. Abbreviations: Gra—gradulus; Med—median body.

FIGURE 21. Austroplebeia male genitalia. Figs a – c. Genitalia, dorsal view on left, ventral view on right: a, A. cincta; b, A. essingtoni; c, A. magna sp. nov. Figs d – e. Apical abdomen and protruding parts of genitalia, viewed laterally, as visible in many pinned male specimens: d, A. essingtoni, showing distinct curve in apical gonostylus; e. A. magna sp. nov., with gently curved apical gonostylus. Figs a – c drawn to same scale. Abbreviations: Pen—penis valve; Gon—gonostylus.

FIGURE 22. Austroplebeia worker faces: a, A. cincta NG; b, A. cincta QLD; c, A. essingtoni, showing a relatively heavily marked specimen within the species range; d, A. australis – Eastern Colour Morph; e, A. cassiae; f, A. magna sp. nov. Scale bars = 0.25 mm.

FIGURE 23. Austroplebeia male faces: a, A. cincta QLD; b, A. essingtoni; c, A. australis – Eastern Colour Morph; d, A. australis – Central Colour Morph; e, A. cassiae; f, A. magna sp. nov. Scale bars = 0.25 mm.

FIGURE 24. Austroplebeia queen faces: a, A. cincta QLD; b, A. essingtoni; c, A. australis – Eastern Colour Morph; d, A. australis – Central Colour Morph; e, A. cassiae; f, A. magna sp. nov. Scale bars = 0.25 mm.

FIGURE 25. Austroplebeia lateral thoraces: Figs a – b. Worker mesosomal side: a, A. cincta QLD; b, A. cassiae. Figs c – d. Male mesosomal side: c, A. cincta QLD; d, A. cassiae. Figs e – g. Detail of mesepisternum pilosity on male mesosomal side (photographs by K. Walker): e, A. australis; f, A. cassiae; g, A. magna sp. nov. Figs e – g shown at same magnification; all scale bars = 0.25 mm. Abbreviation: Met—metepisternum.

FIGURE 28. Observed distribution of all Austroplebeia species in Australia and the island of New Guinea: a, A. cincta; b, A. essingtoni; c, A. australis; d, A. magna sp. nov. and A. cassiae. In all maps, square symbols represent nest samples and circles represent samples collected from flowers or traps. The type locality for each named species, including those now synonymised, is indicated with arrows. Where the type locality was a general area such as ' Central Australia' or ' Cape York', these areas are indicated with shading.

FIGURE 29. Austroplebeia nest entrances: a, A long A. cincta tunnel (120 mm) near Rossville, QLD; b, The tunnel of an A. essingtoni colony that has nested in a cliff face crevice 65 k S of Maningrida, NT (photograph by Aung Si); c, A translucent fresh tunnel of an A. australis colony near Tara, QLD (photograph by M. Halcroft); d, An A. australis colony without an entrance tunnel, near Tara, QLD (photograph by M. Halcroft); e, A thicker and older tunnel of an A. cassiae colony near Rossville, QLD; f, The tunnel of an A. magna colony 50 k S of Maningrida, NT (photograph by Aung Si); g, The longest tunnel recorded in this study: the 430 mm tunnel of an A. cincta colony that was being harassed by green ants near Rossville, QLD; h, Another long tunnel (ca. 120 – 130 mm) of an A. magna sp. nov. colony 50 k S of Maningrida, NT. Green ants can also be seen on this tunnel (photograph by Aung Si); i, The 160 mm tunnel of an A. cassiae colony near Rossville, QLD. The green ants seen on this tunnel have caught two forager bees.

FIGURE 30. Nest tunnels photographed at night (ca. 11 pm) near Rossville, QLD: a, An A. cassiae tunnel closed by a lacy mesh of fine resinous droplets (this tunnel closure style is also common in A. australis); b, An A. cincta tunnel which was left completely open; c, An A. cincta tunnel partially closed by an almost solid wall of cream waxy flakes.

FIGURE 31. Internal nest characteristics and brood comb of an A. cincta colony near Rossville, QLD: a, The multi-pocket batumen sheath enclosing the whole nest within the 170 mm diameter tree cavity; b, Brood comb and honey pots revealed when the upper layer of batumen was removed from the central nest area (arrow indicates six concentric layers of larval brood cells at the top of the brood comb); c, Outer surface of the brood with the newest brood cells of the advancing front waxed together into a solid layer; d, Side view of the advancing front of the brood showing the cells arranged in concentric layers; e, Cocoons in an irregular arrangement in the central area of the brood. Abbreviations: Bat—batumen layer; Bro—brood comb; Hon—honey pots.

FIGURE 33. Honey and pollen storage pots in Austroplebeia colonies: a, Translucent honey pots in an A. cincta colony near Rossville, QLD; b, Honey pots with thick, strongly pitted walls in an A. australis colony near Tara, QLD (photograph by M. Halcroft); c, Honey pots in an A. magna sp. nov. colony 50 k S of Maningrida, NT (photograph by Aung Si); d, Pollen pots in an A. cincta colony near Rossville, QLD; e, Pollen pots with thickened pitted walls in an A. australis colony near Tara, QLD (photograph by M. Halcroft); f, Pollen pots with strongly pitted walls in an A. australis colony near Kilcoy, QLD; g, Pollen pots made from red-brown cerumen in an A. cassiae colony at Conjuboy, QLD.