Austroplebeia australis (Friese)

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 : 43

Austroplebeia australis (Friese)

( Figures 1–20 , 22–26 , 28–29 , 32–33 )

Trigona australis Friese 1898: 427 , 430, 431.

Austroplebeia australis — Moure 1961: 196; Michener 1990: 134, 137. Trigona (Plebeia) australis — Michener 1965: 222, 230, 244.

Trigona cincta percincta Cockerell 1929a: 242 . New Synonymy. Austroplebeia cincta percincta — Moure 1961: 197.

Trigona (Plebeia) percincta — Michener 1965: 230.

Austroplebeia percincta — Michener 1990: 134; Rasmussen 2008: 10 (as Austroplebeia percinta )

Trigona cockerelli Rayment 1930: 57 . New Synonymy.

Austroplebeia cockerelli — Moure 1961: 197; Michener 1990: 134. Trigona (Plebeia) cockerelli— Michener 1965: 230.

Trigona cockerelli ornata Rayment 1932: 107 ;— Rayment 1935: 738 (more detailed redescription as new subspecies). New Synonymy.

Austroplebeia cockerelli ornata — Moure 1961: 197.

Trigona (Plebeia) ornata— Michener 1965: 230.

Austroplebeia ornata — Michener 1990: 134.

Trigona websteri Rayment 1932: 105 . New Synonymy.

Austroplebeia websteri — Moure 1961: 197; Michener 1990: 134. Trigona (Plebeia) websteri— Michener 1965: 230.

General diagnosis of Austroplebeia australis . In workers and males, frons and mesepisternum with plumose hair ( Figs 22 d, 23 c–d, 25e), head width ≥ 1.59 mm ( Figs 10 , 14 ). In workers, HBW 0.29–0.40 mm ( Fig. 11 ). Most workers have the following characteristics: thorax markings Grade 2–11 ( Figs 5 , 7 ), pronotal collar and legs with cream or yellow maculations, plumose hair on clypeus sparse ( Fig. 22 d), bristles on basitarsus III golden. In males, gonostylus gently curved, thorax markings Grades 6 and 10–13, mesepisternum plumose hairs usually with long evenly spaced barbs and a broad triangular shape ( Fig. 25 e), HBW 0.23–0.29 mm ( Fig. 13 ). In queens, short dense hair covering T6, but absent on T4–T5. Distribution WA, NT, QLD and NSW ( Fig. 28 c).

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 3. Variation in worker face colour grades observed within all Austroplebeia taxa except A. cincta. Data show 300 workers from 114 colonies, in addition to 50 workers from 10 flower samples of A. australis – Western Colour Morph. Colour grades are as illustrated in Fig. 1.

FIGURE 4. Variation in male face colour grades observed within all Austroplebeia taxa except A. cincta and A. australis – Western Colour Morph. Data show 186 males from 38 colonies. Colour grades are as illustrated in Fig. 2.

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

FIGURE 6. Number of different thorax colour marking grades found amongst workers within individual colonies of Austroplebeia. Data are based on 122 colonies and scores of 10 – 49 workers per colony.

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 12. Ratio of tibia III width and basitarsus III width in workers in a large sympatic population of A. australis – Eastern Colour Morph and A. cassiae near Duaringa, QLD. Data points are averages from two workers per colony. Labelled data points are nests for which the species identification was confirmed in the molecular analysis of Halcroft et al. (2015). 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 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 26. An A. australis worker with the distinctive orange abdomen, that is common in western QLD populations (photograph by D. Clarke).

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 32. Internal nest characteristics and brood combs of species other than A. cincta: a, Nest of an A. essingtoni colony at Broome, WA (photograph by T. Heard); b, Brood comb of an A. australis colony in a natural log near Ti Tree, NT; c, Brood comb of a boxed colony of A. cassiae near Rossville, QLD; d, Brood comb of an A. magna sp. nov. colony in a narrow tree cavity, 50 k S of Maningrida, NT (photograph by Aung Si). Abbreviations: Lar—larval brood cells; Coc—cocoons; Pol—pollen pots; Hon—honey pots; Bat—batumen layer.

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.