Emeia

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 : 10-13

Emeia gen nov. Fu, Ballantyne and Lambkin

( Figs 1–6 , 8 , 16–30 )

Type species. Curtos pseudosauteri Geisthardt 2004 by present designation.

Diagnosis. Emeia gen. nov. is distinguished by its unusual terrestrial larva where the thoracic and abdominal terga differ – the lateral thoracic tergal margins are broad, while those of the abdomen narrow and curve posteriorly. It belongs to a group of Luciolinae where the aedeagal sheath has the posterior area of the sternite evenly emarginate on the right side only, and the lateral lobes of the aedeagus are widely visible at the sides of the median lobe from below. It differs from Aquatica Fu et al. which has pointed projections along both sides of the sheath sternite emarginations and fully aquatic larvae with gills. It is distinguished from genera in the Atyphella complex ( Fig. 9 Node 55) by the subparallel-sided pronotum the sides of which are flattened along its length, and which is narrower than the width across the elytral humeri. It differs from Missimia Ballantyne , in having both a distinct clypeolabral suture and flexible labrum ( Missimia has no clypeolabral suture and an inflexible labrum); from Luciola cruciata and L. owadai ( Fig. 7 Node 1) in having an expanded base of the epipleuron and humerus not visible (both Luciola spp. have the elytral epipleuron non expanded at its base and the humerus thus visible from below). Curtos Motschulsky has a distinctive longitudinal elytral humeral carina, large well spaced elytral punctation and aedeagal lateral lobes of uneven length. Emeia gen. nov. lacks the carina and pronounced punctation, and the aedeagal lateral lobes are subequal in length.

Description. Male. Pronotum ( Fig. 1 ) dorsal surface without irregularities in posterolateral areas and longitudinal groove in lateral areas; punctation dense. Anterior margin not explanate. Pronotum subparallel-sided, margins straight (B=C); pronotal width <humeral width; anterolateral corners rounded obtuse; lateral margins without indentation at mid-point, or sinuousity in either horizontal or vertical plane; without indentation in lateral margin near posterolateral corner, and irregularities at corner; posterolateral corners, rounded, <90°; posterolateral corners projecting beyond median posterior margin and separated from it by defined emarginations.

Hypomera closed. Median area of hypomeron not elevated in vertical direction; all of hypomeron flattened to neck and closely adpressed; pronotal width/ GHW index 1.4–1.5.

Elytron ( Fig. 1 ) punctation dense, not linear, not as large as those on pronotum, nor widely and evenly spaced; apices not deflexed; epipleuron and sutural ridge extend beyond mid-point, almost to apex, not extending further around apex, neither thickened in apical half; no interstitial lines; elytral carina absent; in horizontal specimen viewed from below epipleuron at elytral base wide, covering humerus; viewed from above the anterior margin of the epipleuron arises anterior to posterior margin of MS; epipleuron developed as a lateral ridge along most of length; sutural margins approximate along most of length in closed elytra; lateral margins slightly convex-sided.

Head moderately depressed between eyes; moderately well exposed in front of pronotum, not capable of complete retraction within prothoracic cavity; eyes moderately separated beneath at level of posterior margin of mouthpart complex; eyes above labrum moderately separated; frons-vertex junction rounded, without median elevation; posterolateral eye excavation not strongly developed, not visible in resting head position; antennal sockets on head between eyes, not contiguous, separated by <ASW; clypeolabral suture present, flexible, not in front of anterior eye margin when head viewed with labrum horizontal; outer edges of labrum reach inner edges of closed mandibles.

Mouthparts functional; apical segment of labial palpi non-lunate, strongly flattened, of form of a wide triangle (widest at base and L 2– 3 X W), with inner edge dentate and at least half as long as apical maxillary palpomere. Antennae 11 segmented; length> twice GHW; no segments flattened, shortened, or expanded; pedicel not produced; FS1 not shorter than pedicel.

Legs ( Fig. 2 ) with inner tarsal claw not split; without MFC; no femora or tibiae swollen or curved; no basitarsi expanded or excavated.

Abdomen ( Figs 2 , 20, 21 ) without cuticular remnants in association with aedeagal sheath; no ventrites with curved posterior margins nor extending anteriorly into emarginated posterior margin of anterior segment; LO in V7 entire occupying half of V7, and not reaching to sides or posterior margin, whitish material reaching into MPP is probably fat body and not organized LO material; posterior half of V7 not arched or swollen, muscle impressions not visible in this area; neither anterior nor posterior margin of LO emarginate; LO present in V6, occupying almost all V6. MPP present, symmetrical, apex shallowly emarginate, not laterally compressed, about as long as wide (L=W), not inclined dorsally nor engulfed by T8 apex, without dorsal ridge, median longitudinal trough. V7 without median carina, median longitudinal trough, anteromedian depression on face of LO, incurving lobes or pointed projections, median ‘dimple’, or reflexed lobes; posterior margin of V7 without PLP and posterolateral corners rounded. T7 without prolonged anterolateral corners. T8 well sclerotised, symmetrical, W=L, visible posterior area not narrowing abruptly, median posterior margin not emarginate; widest across middle with lateral margins subparallel-sided in anterior half and tapering evenly in posterior half to a rounded partly truncate posterior margin; without prolonged posterolateral corners, median posterior projections, not extending conspicuously beyond posterior margin of V7; posterior margin slightly inclined ventrally but not engulfing posterior margin of V7 nor MPP; T8 ventral surface ( Fig. 22 ) without median longitudinal trough; without lateral depressed troughs, asymmetrical projections, median posterior ridge; concealed anterolateral arms of T8 as long as visible posterior portion of T8, not laterally emarginated before their origins, expanded dorsoventrally, and appearing narrow from below; without bifurcation of inner margin and ventrally directed pieces; lateral margins of T8 not enfolding sides of V7.

Aedeagal sheath ( Figs 16, 17 ) approx. 3 times as long as wide; without bulbous paraprocts; similar in outline to aedeagal sheath of Atyphella Olliff species with sheath sternite emarginate on its right side from point of articulation with tergite; anterior half of sternite broad, apically rounded; tergite without lateral arms extending anteriorly at sides of sheath sternite; tergite without projecting pieces along posterior margin of tergite 9, anterior margin without transverse band.

Aedeagus ( Figs 16, 19 ) length/width 2.5/1; LL lack lateral appendages; LL visible from beneath at sides of ML, LL/ML wide; LL of equal length, slightly longer than ML, separated longitudinally by most of their length; LL apices outturned with preapical outer margin angulate; dorsal base of LL slightly asymmetrical, not excavated; LL without lateral hairy appendages along their outer ventral margins, not produced preapically nor narrowly on inner apical margin; without projection on left LL; inner margins without slender leaf-like projection; ML symmetrical, without paired lateral teeth and tooth to left side, not strongly arched, apex not shaped like arrowhead, not bulbous, not inclined ventrally; BP not strongly sclerotised, not hooded, not strongly emarginated along anterior margin.

Female ( Figs 3, 4 , 24, 25 ). Brachelytral and assumed incapable of flight. Elytral margins expanding posteriorly and elytra not contiguous along sutural margins in apical ¼; three tergites protrude beyond elytral apices. Pronotal outline similar to that of male with sides largely subparallel, posterolateral corners not projecting and emarginations along posterior margin scarce; pronotal width slightly greater than humeral width. Elytral punctation not as large as that of pronotum, nor evenly spaced; no interstitial lines; elytral carina absent. No legs or parts thereof swollen and/or curved. LO in V6 widely bipartite with intervening fat body somewhat scattered, without any elevations or depressions or ridges on V7; median posterior margin of V7 shallowly emarginate; median posterior margin of V8 broadly and shallowly. Genitalia as figured ( Fig. 23 ). No obvious bursa plates.

Larva ( Figs 5, 6 , 26–30 ). Associated by breeding; terrestrial; superficially resembling a trilobite-like larva (e.g. Dulticola hoiseni Wong) ( Fig. 30 ); with 3 thoracic and 10 abdominal terga and a thin median line extending from the anterior margin of thoracic tergum 1 to the posterior margin of abdominal tergum 9; lateral margins of thoracic terga explanate and flattened; lateral margins of abdominal terga 1–9 narrowly explanate, narrowly prolonged and curved posteriorly; lateral margins of abdominal tergum 10 parallel-sided, not explanate; protergum wider than long, with median anterior margin indented, lateral margins behind anterior margin with short paired rounded projections, lateral margins diverging posteriorly, posterolateral corners angulate and <90°, and posterior margin largely straight; anterolateral corners of terga 2, 3 broadly rounded, obtuse, lateral margins convex-sided, posterolateral corners slightly narrowed and slightly produced, posterior margin straight, may incline slightly towards mid line; arrangement of ventral surface conforming to that described for Pteroptyx valida Olivier (Ballantyne & Rasainthiran Menayah 2002) : an elongate pleural suture runs from anterior margin of mesothorax to posterior margin of abdominal segment 9, delimiting laterotergites bearing spiracles above and laterosternites and a single median sternal element below; in the thorax the median sternal elements are divided into two, and each is margined by laterotergites (only the mesothoracic laterotergites bearing spiracles). Head and antennae ( Figs 26, 27 ) of typical Luciolinae form as described in Ballantyne and Rasainthiran Menayah (2002); mandibles with a single inner tooth; antennae ( Fig. 28 ) with short slender terminal segment surmounted by hairs; sense cone elongate almost as long as AS 3; maxillary and labial apical palpomeres elongated pointed with terminal sense organs ( Figs 28, 29 ). Legs: without brush of hairs from apex of tibiotarsus.

Etymology. Emeia is regarded here as a feminine noun latinised by the addition of an “a” to the name of the mountain where this species was first discovered. Fu has given Emeia pseudosauteri a Chinese name “Sanyechong Ying () ” meaning trilobite firefly. “Sanyechong” is an anglisized version of the Chinese word for trilobite, while “Ying” is anglisized from the Chinese word for firefly.

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.

FIGURE 8. Majority rule tree, consensus of 169 MPT of length 5609 from phylogenetic analysis of 143 taxa and 436 morphological characters in Appendix 2. Part 2 Nodes 35 – 52. Node numbers red, bold, italics. Undescribed species in red, bold with identification numbers blue, bold, italics.

FIGURE 9. Majority rule tree, consensus of 169 MPT of length 5609 from phylogenetic analysis of 143 taxa and 436 morphological characters in Appendix 2. Part 3 nodes 55 – 76. 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).