Lepidotrigona satun, Attasopa & Bänziger & Disayathanoowat & Packer, 2018

Attasopa, Korrawat, Bänziger, Hans, Disayathanoowat, Terd & Packer, Laurence, 2018, A new species of Lepidotrigona (Hymenoptera: Apidae) from Thailand with the description of males of L. flavibasis and L. doipaensis and comments on asymmetrical genitalia in bees, Zootaxa 4442 (1), pp. 63-82 : 74-76

Male of L. doipaensis

Lepidotrigona doipaensis ( Schwarz, 1939) , measured as range (Average±SD, n=4).

Figs. 2 : C1–4, 3: C1–4 & 7

Diagnosis. Males of L. doipaensis can be differentiated from the other two Lepidotrigona species of the L. ventralis species group known from Thailand as follows (see also diagnosis of L. satun above). S4 slightly concave apicomedially ( Fig. 2 : C1) (strongly concave and convex in L. satun and L. flavibasis respectively). The apicosubmedial lobes of S5 pointed apically (as in L. flavibasis , rounded in L. satun ), with one very long seta and often a much shorter one (two very short setae in L. flavibasis , 4–7 setae of intermediate length in L. satun ). S4 gradulus touches the antecosta ( Fig. 2 : C1) (at least slightly separated from the antecosta in the other two species ( Fig. 2 : A1, B1)). S5 gradulus mostly transverse and touching antecosta medially ( Fig. 2 : C2) (not touching the gradulus in L. satun and doing so only briefly in L. flavibasis ). Hairs on dorsal surface of metatibia dark brown intermixed with greyish yellow ones ( Fig. 7 : B) (only greyish yellow hairs in L. flavibasis , but variably brown, dark brown or greyish yellow in L. satun ). The gonostylus and genital capsule are also clearly different in the three species (see descriptions and Fig. 3 ). The ratio of the forewing diagonal to the length of the 2nd submarginal cell separates all three species ( Table 1) and see diagnosis of L. satun above.

Description. As for the holotype of L. satun n. sp. except as follows:

Structure: Body length 4.85–5(4.89±0.07) mm; head width 1.9–1.95 (1.93±0.02) mm; head length 1.42–1.48 (1.45±0.02) mm; eye width 0.55–0.58 (0.57±0.01) mm; gena width 0.18–0.19 (0.19±0.01) mm; interocellar distance 0.39–0.42 (0.4±0.01) mm; ocellocular distance 0.25–0.27 (0.26±0.01) mm; upper interorbital distance 1.08–1.11 (1.09±0.01) mm, lower interorbital distance 0.78–0.8 (0.79±0.005) mm; scape length excluding basal bulb 0.52–0.58 (0.55±0.02) mm, with basal bulb 0.61–0.67 (0.64±0.02) mm; 1 st flagellomere length 0.11–0.13 (0.12±0.01) mm; 2nd flagellomere length 0.2–0.22 (0.21±0.01) mm, width 0.13–0.14 (0.14±0.001) mm; 3rd shorter than 2nd; 4th longer than broad; malar space length 0.03–0.04 (0.04±0.001) mm. Forewing length 4.55– 4.76 (4.66±0.08) mm, width 1.7–1.76 (1.73±0.02) mm; forewing diagonal 1.28–1.34 (1.3±0.03) mm, length of 1 st submarginal cell 0.3–0.32 (0.31±0.01) mm, 2nd submarginal cell length 0.62–0.67 (0.65±0.02) mm. Metatibia length 1.61–1.73 (1.67±0.04) mm, width 0.62–0.66 (0.64±0.01) mm; metabasitarsus length 0.57–0.61 (0.59±0.02) mm, width 0.4–0.41 (0.41±0.005) mm. S4 broadly emarginate apicomedially, depth of emargination 0.15 times length of sternum medially; gradulus of S4 slightly concave medially; S5 apical margin with two long, narrow, acute lobes that delimit an emargination ~0.45 times as deep as length of sternum, emargination approximately as long as wide, submedial lobes each bearing a long, occasionally also a short, thick apical seta, S5

gradulus transverse touching antecosta medially; S6 apical margin convex medially with short acute process, S7 ~twice as wide as long, apical margin weakly emarginate, bearing some distinct hairs apicomedially. Genital capsule dark brown to black except base of penis valve, apical half to 2/3 of gonostylus, and gonocoxa anteriorly which are pale brown to brown. Penis valve curved ventrally, curvature strongest on basal third to half, then almost straight, valves normally in contact with each other (exceptionally not so as in Fig. 3 : C1–4) and the right valve overarching the left valve. Gonostylus sclerotized basally, medial surface setose on apical ~3/7, approximately 10 times longer than wide (length 0.67–0.71 mm, width 0.062–0.073 mm).

Coloration of integument: Head black except as follows: yellowish brown on basal bulb and extreme apex of scape (sometimes ventral surface of scape entirely yellowish brown); apical 2/3 of mandible; pedicel, and all flagellomeres dark brown. Mesosoma black except tegula; all coxae and femora black; trochanters brown; tibiae brown to black; all tarsi yellowish brown. Metasomal terga dark brown except basal depression and posterior margin of T1 yellowish brown; S1–S3 brown, except S3 laterally dark brown; S4 with large lateral dark brown spot; S5 dark brown apically, paler medially; S6 pale brown except paler on disc; S7 translucent with large lateral mark and gradulus brown.

Pubescence: Face with plumose dense appressed white hairs; frons, vertex, lower genal area, and lower edge of mandible with long pale whitish brown hairs; longest hairs of vertex ~3/4 times as long as scape. Mesoscutum and mesoscutellum with long and very short pale whitish brown hairs, the longest hairs slightly shorter than those of vertex; mesoscutum lacking distinct band of short plumose scale-like yellow hairs; coxa, trochanter, and femora of all legs with pale brownish white hairs; all tibiae with pale brown to greyish yellow hairs, intermixed with short dark brown hairs; metatibia with short dense brownish white keirotrichia.

Surface sculpture: As for male L. flavibasis .

Material examined. Type material: Holotype (worker, NMNH); Type locality: THAILAND; labelled as follows: “Doi Pa/ Mai Deng/ Siam 750m / 12-29-32 ”, “HughMSmith/ Coll”, “TypeNo./ 53563/ U.S.N.M.”, “Holotype”, “ Trigona ventralis / var. doipaensis / H.F. Schwarz”, “7080102”. [Examined and measured in Table 1]. Paratypes (2 workers, AMNH), labelled as follows: “Doi Pa/ Mai Deng/ Siam 750m / 12-29-32 ”, “HughMSmith/ Coll”, “PARATYPE”, Trigona ventralis / doipaensis / H.F. Schwarz”, “acc 36579”. [Examined and measured in Table 1].

Additional material: Measured male specimens included in description and Table 1 (collected from wild nests): THAILAND, Chiang Mai Prov.: Doi Inthanon, 17.i.2016, K. Attasopa (Nest MYAL5 , 2 males); Doi Suthep, Chang Khian stream area, 1020 m , 11.iv.2016, H. Bänziger (Nest CK 4, 2 males, caught leaving nest [not swarming]). Measured worker specimens included in Table 1 (collected from wild nests): Chiang Mai Prov.: Doi Inthanon , 17.i.2016, K. Attasopa (Nest MKLL1, 1 worker; nest MKLL4, 1 worker; nest MYAL3, 1 worker); Doi Suthep, Chang Khian, 1020 m, 29.ix.2010, H. Bänziger (Nest CK4, 1 worker); Doi Suthep, 26.xii.2015, K. Attasopa (Nest DSTL3 , 1 worker). Non-measured specimens (collected from wild nests): Chiang Mai Prov.: Chaiprakan, 710 m , 20.ii.2010, H. Bänziger (Nest CP9, 13 workers), 11.iv.2011 (Nest CP26, 4 males, 6 workers, swarming), 16.iv.2016 (Nest CP26, 11 males, 2 workers, caught as leaving nest); Doi Suthep, Chang Khian stream area, 1020 m, 19.iii.2009, H. Bänziger (Nest CK4, 12 workers), 5.viii.2009 (Nest CK4, 4 workers), 19.viii.2009 (Nest CK4, 4 workers), 29.ix.2010 (Nest CK4, 5 workers), 11.iv.2016 (Nest CK4, 10 males, 2 workers, caught as leaving nest); Doi Suthep, Chang Khian stream area, 1040 m, 4.xii.2011, H. Bänziger (Nest CK11, 7 workers), 11.iv.2016 (Nest CK11, 11 males, 3 workers, caught as leaving nest); Doi Inthanon, 17.i.2016, K. Attasopa (Nest MKLL1, 2 workers; nest MKLL4, 2 workers; nest MYAL3, 2 workers); Doi Suthep, 26.xii.2015, K. Attasopa (Nest DSTL3, 2 workers); Doi Suthep, W of temple, 1070 m, 1.iv.2017, H. Bänziger (Nest SHQ1, 8 workers); Doi Suthep northern sector, QSBG area, 25.iii.2010, H. Bänziger (Nest, 13 workers); Hill opposite QSBG, 25.iii.2010, H. Bänziger (Nest in tree trunk, 1 worker); Pa Pä, Ban Huay Phra Chao, 29.vi.2008, H. Bänziger (Nest, 12 workers); North of Chiang Dao Dist ., 6.xi.2008, H. Bänziger (Nest TL26, 8 workers), 8.ii.2009, H. Bänziger (Nest TL26, 6 workers).

Genitalia examined: MYAL 5-01, MYAL 5-02, nest MYAL 5, Doi Inthanon, 17.i.2016; GP 3182, 3183, 3191, nest CK4, Chang Khian, Doi Suthep, 11.iv.2016; GP 3179, 3180, 3192, 3258, 3259, 3260, nest CK11, Chang Khian, Doi Suthep, 11.iv.2016.

Comments. Based upon the colour of pubescence, the male of L. doipaensis might be misidentified as L. flavibasis because it has pale hairs on the vertex and mesoscutellum typical for the worker of the latter species. However, due to the association of the two sexes collected together in the field, the males described above are certainly L. doipaensis despite the fact that the hairs are dark in workers of this species.

Figures

FIGURE 2. Male metasomal sterna, ventral aspect labelled as: (A), (B), and (C) refer to L. satun n. sp. (Paratype, H.B.- GP3311), L. flavibasis (H.B.-GP3322), and L. doipaensis (H.B.-GP3183) respectively, with the number following as (1), (2), (3), and (4) refer to S4, S5, S6, and S7 respectively. All subfigures are shown at the same scale and magnification. Diagonal lines indicate the characters treated in the diagnoses.

FIGURE 3. Male genital capsules, labelled as: (A), (B), and (C) refer to L. satun n. sp. (Paratype, H.B.-GP3311), L. flavibasis (H.B.-GP3322), and L. doipaensis (H.B.-GP3183) respectively, with the number following as (1), (2), (3), and (4) refer to dorsal, ventral, lateral, and caudal aspect respectively. All subfigures are shown at the same scale and magnification. Diagonal lines indicate the right penis valve.

FIGURE 7. Male of L. doipaensis from the mountain near the type locality (Doi Suthep, Chang Khian, Chiang Mai, Thailand). (A) dorsal habitus, (B) lateral habitus, and (C) head, frontal view.