Emeia pseudosauteri (Geisthardt)

Fu, Xinhua, Ballantyne, Lesley & Lambkin, Christine, 2012, Emeia gen. nov., a new genus of Luciolinae fireflies from China (Coleoptera: Lampyridae) with an unusual trilobite-like larva, and a redescription of the genus Curtos Motschulsky, Zootaxa 3403, pp. 1-53 : 14

Emeia pseudosauteri (Geisthardt)

Curtos pseudosauteri Geisthardt, 2004:1 .

Type. Male. CHINA. 29°31’44”N, 103°19’44’’E, Sichuan, Mt Emei , 600–1050m, asl, 05– 19.05.1989, L. Bocak (Staatliches Museum fur Naturkunde, Stuttgart, Germany). Not examined by these authors .

Specimens examined. CHINA: Si Chuan Province, E Mei Mountain, 1030m, 10.30 pm, 24.VI. 2006, X. H. Fu, female ( ANIC). E Mei mountain , no other data, 5 males, 2 larvae X. H. Fu ( ANIC); Si Chuan Province , Tian Tai mountain , Qionglai County, Chengdu City, 839m, 8.20 pm, 29. IV. 2010, X.H. Fu, 21 males, 5 females, 8 fifth instar larvae (larvae bred from eggs) ( NHMHAU) .

Diagnosis. As this is the only species in the genus, the generic features characterise it adequately. The only Luciolinae species known to possess a “trilobite-like” larva.

Male ( Figs 1, 2 , 16–22 ). 9.0–10.3 mm long; 4.0 mm wide; width/length approx. 0.4. Colour: Pronotum pale cream, semitransparent with median dark brown area extending from anterior to posterior margin; pronotum in fresh specimens has extensive lateral areas of pinkish fat body; elytra, MN, MS, head antennae and mouthparts, thorax ventrally and all legs, V2–5 and T2–6 very dark brown; elytra in freshly collected specimens has apex narrowly pink; light organs in V6, 7 white, retracted from lateral and posterior margins in V7 which are slightly yellowish and semitransparent; T 7, 8 mottled paler brown and semitransparent. Pronotum 1.5 mm long 2.3 mm wide; GHW 1.7–2.0mm; SIW 0.2–0.4mm; ASD <ASW. Elytron 7.5– 8.8 mm long.

Female ( Figs 3, 4 , 23–25 ). Coloured as for male (pronotum and elytral apices have pinkish fat body in fresh specimens; colour fades in ethanol); terminal abdominal tergites protruding beyond elytral apices are dark brown; LO in V6 white, rest of V6 and V7 dark brown; ventral aspect of V8 paler brown.

Larva ( Figs 5, 6 , 26–30 ). Colour: dorsal surface mainly brown, shiny, with some brown mottling, except for paler brown abdominal tergites 7, 8; ventral surface paler brown, especially in median sternal area of thorax and abdomen, with laterotergites in thorax and abdomen very dark brown; ventral surface of margins of terga in abdomen dark brown except for pale abdominal segments 7, 9; abdominal sternal plates 1–6 and sometimes also 7 with brown oblique cuticular strands.

Biological notes. Observation conducted by X.H. Fu in Mt. Tian Tai (Lancaozi, Xiaojiawan, N 30° 17.113’ E 103° 08.242’). Specimens were observed from the end of April to the end of May. Egg period is about 27 days. Larvae preyed on small land snails Bradybaena ravida sieboldiana Pfeiffer 1850 . Larval periods were as follows: First instar, 16.8 ±3.9 days (mean ±SD) n=37; Second instar, 17.6±2.2 days, n=31; Third instar, 15.8±1.5 days, n=25; Fourth instar, 17.5±1.5 days, n=20. Flashing males usually flew not higher than 1m above grass with single short flashes of 0.59±0.09 (n=31) sec (mean±SD) duration ( Fig. 31), and intervals of 0.53±0.08 (n= 41) sec (mean±SD). The females were observed on leaves and stems of the grasses and have quick flashes with 0.20±0.03 (n=11) sec (mean±SD) duration and intervals of 0.34±0.12 (n= 5) sec (mean±SD).

Discussion. This new genus from the mountainous region of E Mei and Tian Tai in China has an interesting mixture of characters. While the aedeagus is similar to genera in the Atyphella ‘complex’ of Ballantyne and Lambkin (2009) in having the lateral lobes clearly visible from beneath at the sides of the median lobe, and the aedeagal sheath with the posterior area of the sternite evenly emarginated, certain other features are in common with the Luciola / Pteroptyx complex ( Fig. 7 Node 18). The pronotum is parallel-sided and slightly narrower than the width across the elytral humeri, and has the unique feature of having the pronotal hypomera quite flattened and closely adpressed along their length. The prolongation of the abdominal MPP resembles that of Pygoluciola Wittmer , but it does not incline dorsally and is not enveloped by the apex of T8. Emeia gen. nov. is one of only three lucioline genera in which the females are flightless ( Table 3 ). Atyphella species females (with one exception) are flightless and occur for the most part in Australia in patches of rainforest along the eastern coastal strip as far south as Kiama. In most locations only one species is known ( Ballantyne & Lambkin 2000, 2009). Bourgeoisia hypocrita Olivier females are found in rotting leaf litter in Fiji where there appears to be just one species of firefly, but little is known of the male/female interaction ( Deheyn & Ballantyne 2009). Nothing is known of the interactions in Lampyroidea Costa.

One of the most interesting and unusual features of the new genus is its larva, which superficially resembles both the ‘trilobite’ larva of Brues (1941) and Mjöberg (1925), and Dulticola hoiseni Wong (Wong 1996), but not the Singaporean “trilobite” larva described by Lok (2008). Many of these larvae belong to the family Lycidae and may be larviform females. However not all these reports may be of Lycidae as Chan (2007, as reported in Lok, 2008) observed a luminous species in Thailand which while termed a trilobite-like larva has broadly laterally explanate tergal margins on all but the terminal tergum and may well be a larva of a Diaphanes Motschulsky.

Figures

FIGURE 7. Majority rule tree, consensus of 169 MPT of length 5609 from phylogenetic analysis of 143 taxa and 436 morphological characters in Appendix 2. Part 1 Nodes 1 – 34. Node numbers red, bold, italics. Undescribed species in red, bold with identification numbers blue, bold, italics.

FIGURES 1 – 6. Habitus Emeia pseudosauteri. 1, 2 male; 3, 4 female; 5, 6 larva (1, 3, 5 dorsal; 2, 4, 6 ventral) (Scale bar = 5 mm).

FIGURES 16 – 25. Emeia pseudosauteri male 16 – 22, female 23 – 25. 16, 17 aedeagal sheath (right margin of posterior section of sheath sternite arrowed in 16). 18, 19 aedeagus. 20 – 21 entire abdomen. 22 T 8. 23 genitalia, anterior end to top of page. 24, 25 female after prolonged soaking in ethanol, illuminated from below (extent of hind wing arrowed in 24). (16, 18, 20 22, 24 ventral, 17, 19, 21, 25 dorsal). (Scale bar = 1 mm).

FIGURES 26 – 30. Emeia pseudosauteri fifth instar larva SEMs. 26, 27 head. 28 maxillary palp. 29 apex apical maxillary palpomere. 30 body. (27, 28 ventral, 26, 30 dorsal).