Sclerotia aquatilis ( Thancharoen, 2007 ) Thancharoen, 2007

Ballantyne, Lesley A., Lambkin, Christine L., Luan, Xin, Boontop, Yuvarin, Nak-Eiam, Sorasak, Pimpasalee, Suttisan, Silalom, Sommyot & Thancharoen, Anchana, 2016, Further studies on south eastern Asian Luciolinae: 1. Sclerotia Ballantyne, a new genus of fireflies with back swimming larvae 2. Triangulara Pimpasalee, a new genus from Thailand (Coleoptera: Lampyridae), Zootaxa 4170 (2), pp. 201-249 : 214-223

Sclerotia aquatilis ( Thancharoen, 2007) comb. nov.

( Figs 17, 18 , 39−46 )

Luciola aquatilis Thancharoen. Thancharoen et al. 2007: 55 . Ballantyne & Lambkin 2009: 9, 21, 22; 2013 Fig. 3 Node 1. Nec Luciola japonica Kiesenwetter. Ballantyne 1987b: 180 , Fig. 1 g (misidentification).

Holotype. Male. THAILAND. Samut Prakarn Province ( AMNH).

Specimens examined. INDIA. 13 males, 5 females ( ANIC) [female association by label data and similarity of colour only] . THAILAND: Bangkok: Bang Khen District , 2.x.1951 − 12.ix.1965, 76 males, 25 females; Bang Khae District, 2. viii.1951, 7 males; Thon Buri District , 1.vi.−20 . x.1963, 3 males, 1 female. Chanthaburi Province: 21. vii.1964, 1 female ; Kanchanaburi Province: 10−11. viii.1963, 3 males ; Lop Buri Province: 20. ix.1964, 1 male ; Nakhon Nayok Province: 22. ix.1963, 1 male ; Nakhon Ratchasima Province: 14. ix.1963, 1 male, Pak Chong District , 14 . iv.1960, 1 female, 8.vii. 19641 male; Samut Prakarn Province: 17 . vii.1963, 1 male; Saraburi Province: Muak Lek district , 7 . vi.1963, 1 male; Phukhae Subdistrict , 14. ix.1963, 1 male; Trang Province: 6 . v.1964, 1 male (KUIC).

Diagnosis. Distinguished from most species in this genus by the dorsal colouration, which in freshly caught or newly eclosed specimens from Thailand is as follows: Pronotum pale cream (retraction of fat body beneath cuticle may account for very pale brown patches in median area and across posterior margin; Figs 17 , 39, 42, 43 ; Thancharoen et al. 2007: Fig. 1 ); elytra brown, darker brown at base and apex, with a narrowly pale lateral margin narrowing before, and not extending to, or around, apex; suture narrowly pale (colour may be enhanced by somewhat irregular distribution of the underlying fat body); suture may widen a little in posterior 1/3, not extending to, or around, apex; Indian specimens tentatively included here, but not scored, have dark brown elytra which are not darker at base or apex; elytral punctation dark brown; ventral surface largely light brown, tibiae largely pale except for dark brown tibiae 1, and brown apices of tibiae 2, 3. Older (>50 years) pinned Thailand specimens have light brown elytra with lateral margins slightly paler, or elytra very light brown with apex darker brown. The pinned Indian males show a uniform elytral colour. Posterior half of V5 brown. LO in V7 occupying entire area of V7 except for small anterior median emargination which may not be visible in freshly collected specimens. Females macropterous, coloured as for males.

Dimensions: as listed in Thancharoen et al. (2007).

Abdomen ( Figs 40, 44 ): LO in V7 fairly flat, occupying almost all of V7 and with a shallow anteromedian emargination which may not be visible in pinned specimens ( Thancharoen et al. 2007 Fig.1 b).

Aedeagal sheath sclerites ( Figs 45, 46 ): Ventral sclerite roughly triangular in outline with narrower rounded distal end; margins not thickened ( Figs 45, 46 “3”); anterolateral corners acute; right sclerite with transverse projection apically acute and reaching across most of the entire portion of T8 ( Figs 45, 46 “1”); right sclerite with three projections to the right, the posterior one apically acute, the median slender apically rounded and inclining dorsolaterally, and the third, longest projection, inclining ventrolaterally with a rounded hollow apex and arising in an emargination between the other two; left sclerite ( Figs 45, 46 “2”) with three arms, all apically rounded, with anterior arm expanded, rounded and hollow.

Aedeagal sheath: sternite with oblique bar, and slightly off centred small median posterior emargination; median anterior margin of sheath tergite emarginated ( Thancharoen et al. 2007: Fig. 3 a depict this margin as entire).

Aedeagus: L/ W 2.1; length of basal piece/total length 0.4; Thancharoen et al. (2007: Fig. 3 ) depict the LL as being slightly unequal in length.

Remarks. The very distinctive dorsal colour patterns described for Scl. aquatilis by Thancharoen et al. (2007) (as Luciola aquatilis ) have been found to be characteristic only of freshly eclosed specimens. Older dried pinned specimens in KUIC exhibit a less colourful pattern. The similarity of aedeagal sheath and associated sclerites exhibited by specimens Fu et al. (2005) misidentified as Luciola substriata , and Scl. aquatilis , is reconciled here with the description of Sclerotia fui sp. nov. It is possible there is a gradation from the Indian specimens (with dark brown elytra Figs 42, 43 ) through to the somewhat paler specimens in Thailand ( Figs 17 , 39 ) but we were unable to investigate the Indian specimens further.

We investigated several other species of Luciolinae with similar colour patterns to that of the Indian males included here under Scl. aquatilis comb. nov., and conclusions are represented in Table 4 and below.

The conclusions reached based on the information presented below regarding the Luciola s. lato group is largely based on Ballantyne’s investigations in 2013 at MNHN and Ballantyne et al. 2015, Appendix 3 (see Methods and Materials).

Olivier (1891) described a single, wide female from Myanmar (as Burma) as Luciola aemula . His specimen was only a little longer than twice as long as wide, coloured like Luciola ovalis Hope , with a median dark spot on the mesoscutellum. Preliminary investigations by Ballantyne indicate aemula may be synonymous with Asymmetricata ovalis (Hope) .

We have been unable to locate types of L. fukiensis Pic, 1955 , L. limbalis Fairmaire, 1889 , L. nicolleri Bugnion, 1922 , and L. vittata Laporte, 1833 . Pic (1955) thought L. fukiensis was probably just a variety of either L. clara or L. limbalis . It is similarly coloured to L. clara with a small pale area in the anterior area of the suture, but at 6−7 mm long it is much smaller than L. clara (which is 12 mm long). Jeng et al. (2003) located a specimen of L. limbalis in MNHN, identified by Fairmaire. They considered it approached Aq. ficta . It is thus possible that L. fukiensis (at 6−7mm long) could approach L. limbalis , but hardly clara which is much longer. Laporte’s (1833) description of the abdomen of Luciola vittata (penultimate segment white) suggests he may have described a female.

Footnotes: 1. Only lateral margin of elytra pale coloured, suture, apex and remainder dark brown to black; 2. Pale elytral margin extends along lateral and sutural margins and apex; 3. Type is a female; 4. V7 trisinuate; 5. Type is fragmentary or incomplete; 6. Type not located.

Luciola nicolleri was well illustrated in Bugnion (1922) with dorsal colour patterns similar to that of the Indian males addressed here, but we have been unable to locate either a type or any identified males. Based on Bugnion’s diagrams it differs from the Indian males in having the pale elytral margin extending around the apex, the pronotal width is wider than the humeral width and the underside is largely black. Bugnion did not dissect the genitalia. Recent collecting activity in Sri Lanka has not discovered any specimens with this distinctive colouration (Wijekoon pers. com.).

No conclusions can be drawn from the fragmentary type of L. binhana Pic, 1927 . However although the type of L. curticollis Pic, 1927 ( Figs 49, 50 ) is without head, pronotum and abdominal apex, the size of the remainder and the abdominal colouration closely approach that of L. clara ( Figs 47, 48 ). L. clara Olivier, 1907 is a large (ca. 12 mm long), distinctively coloured species without elytral punctation in lines or emarginated LO in V7, and with the posterior margin of V7 rounded. L. noctivaga Olivier, 1907b is coloured like L. ambita Olivier, 1896 and may be the same species ( Figs 5, 6 , 51 ). L. semimarginata ( Figs 13−16 ), and L. timida Olivier, 1883 ( Figs 56−59 ) all have trisinuate posterior margin to V7 and are therefore distinct.

Figures

FIGURE 1. The first of two sections of the Majority rule tree, consensus of 562 MPT of length 5687 from phylogenetic analysis of 145 taxa and 438 morphological characters in Ballantyne et al. (2015, Fig. 1 A) showing Sclerotia Ballantyne gen. nov. and Triangulara Pimpasalee gen. nov. and % of MPTs with the node. For those nodes found in 100 % of MPT, the % is shown in bold.

FIGURE 3. Neighbour Joining bootstrap consensus tree of several aquatic fireflies in South East Asia, with firefly Pyrocoelia pectoralis as outgroup.

FIGURES 17 − 28. Sclerotia gen. nov. spp. males. 17, 18 Scl. aquatilis. 19, 20 Luciola cingulata type male (MCSN). 21, 22 Luciola brahmina type male (MNHN). 23, 24 Luciola seriata holotype male (MCSN). 25, 26 Scl. carinata male (SAMA). 27, 28 Scl. fui sp. nov. paratype males (NHMHAU). 17, 19, 21, 23, 25, 27, 28 dorsal; 18, 20, 22, 24, 26 ventral. Specimens are not to scale and are assembled to allow comparison of elytral and abdominal features.

FIGURES 39 − 44. Scl. aquatilis males and female (41). 39, 40 Thailand (ANIC); 42 − 44 India (ANIC). 39, 42, 53 dorsal; 40, 41, 44 ventral. Scale lines are 1 mm.

FIGURES 45 − 46. Scl. aquatilis aedeagal sheath and aedeagus (posterior half only), sclerites and tergite 8. 45 dorsal; 46 ventral. Scale lines are 1 mm. Figure legend: 1 right sclerite; 2 left sclerite; 3 ventral sclerite; 4 left arm tergite 8; 5 posterior area aedeagal sheath in area of emargination; 6 ML aedeagus.

FIGURES 47 − 55. Luciolinae males Table 4. 47, 48 Luciola clara possible type (MNHN). 49, 50 Luciola curticollis syntype male (MNHN). 51, 55 Luciola noctivaga possible type (MNHN). 47, 49, 51 dorsal (49 elytra only); 48, 50 ventral (50 abdomen and elytra only); 52 − 55 specimen labels. Scale line is 1 mm. Not all figures are to scale, dimensions are quoted in text.

FIGURES 4 − 12. Luciolinae Table 3. 4 − 6 Luciola ambita male (MNHN). 7 − 9 Luciola delauneyi male (MNHN). 10 − 12 Luciola flebilis female (MNHN). 4, 7, 10 specimen label; 5, 9, ventral (9 abdomen only); 6, 8, 11 dorsal (6 anterior body only; 8 elytra only); 12 right lateral. Scale line is 1 mm. Figs 6, 8, 9, 11, 12 are not to scale.

FIGURES 13 − 16. Luciolinae Table 3. Luciola semimarginata syntype male (MNHN). 13 specimen label; 14 dorsal; 15 ventral; 16 ventral detail terminal abdominal ventrites. Scale line is 1 mm.

FIGURES 56 − 62. Luciolinae males Table 4. 56 − 59, 62 Luciola timida (MNHN). 60, 61, 62 Luciola tenuicornis (MNHN). 56, 59, 60, 62 dorsal (59 terminal abdomen only, left posterior arm of tergite 8 arrowed); 57, 58 ventral (58 terminal abdomen only); 61 specimen labels. Scale lines are 1 mm.