Abscondita

Ballantyne, Lesley, Fu, Xinhua, Lambkin, Christine, Jeng, Ming-Luen, Faust, Lynn, Wijekoon, W. M. C. D., Li, Daiqin & Zhu, Tengfui, 2013, Studies on South-east Asian fireflies: Abscondita, a new genus with details of life history, flashing patterns and behaviour of Abs. chinensis (L.) and Abs. terminalis (Olivier) (Coleoptera: Lampyridae: Luciolinae), Zootaxa 3721 (1), pp. 1-48 : 6-9

Abscondita gen nov. Ballantyne Lambkin et Fu

Type species. Abs. terminalis (Olivier) .

Diagnosis. Abscondita gen. nov. belongs to a group of Luciolinae (including Atyphella Olliff ) in which males have aedeagal LL widely visible beside the ML; it differs from all other Luciolinae in that the aedeagus has well sclerotised LL fusing along almost all of their median dorsal length, with very short more membranous projections at the outer angles; LL bear elongate cylindrical lobes just inside their outer lateral margins; the entire light organ occupies almost all of the often very flat V7, which may have a barely developed and very short and wide MPP. The genus is most closely related to certain species of Pygoluciola Wittmer which lack the prolongations of both V7 and T8 (Fu & Ballantyne 2008) and is distinguished from Pygoluciola as follows: the aedeagal sheath sternite expands evenly along its length (in Pygoluciola spp. it is narrow and subparallelsided along most of its length, with expansion near the apex well behind the lateral tergite articulations); the aedeagus has the lateral projections of the outer angles of the LL very short (in Pygoluciola these are greatly elongated and membranous and much longer than the ML); Pygoluciola spp. LL are without the elongate cylindrical lobes. Females are macropterous, some species seen in flight, and have hooked bursa plates. Larvae are apparently terrestrial, with tergal margins thickened and laterotergites not usually visible at sides of body when viewed from above; all tergal plates except the last with four short narrow and apically acute projections along the posterior margins; terminal tergum with sides subparallel; dorsal body plates heavily sclerotised, bearing a profusion of very short spines; no obvious exposed membranous areas visible dorsally; similar to larvae of Pygoluciola qingyu , distinguished in having a single mandibular tooth in all species except anceyi ( qingyu has two), and a rough surface covered in short spines (that of qingyu is smooth) (Fu & Ballantyne 2008).

Description. Male. Pronotum ( Figs 2 , 7 , 18 , 19 , 20 ): dorsal surface without irregularities in posterolateral areas and longitudinal groove in lateral areas; punctation dense; anterior margin not explanate; lateral margins diverging posteriorly (C>B); width subequal to or slightly less than 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 usually rounded obtuse (angulate and slightly less than 90° in promelaena ), projecting a little beyond median posterior margin and separated from it by shallow emarginations.

Hypomera: closed; median area of hypomeron not elevated in vertical direction; posterolateral area flattened and adpressed.

Elytron ( Figs 2 , 7 , 18 , 19 , 20 ): sutural margins approximate along most of length in closed elytra; lateral margins subparallel-sided; apices not deflexed; punctation dense, not linear, not as large as that of pronotum, nor widely and evenly spaced; epipleuron and suture extending beyond mid-point, almost to apex but not as ridge around apex, neither thickened in apical half but suture sometimes expanding slightly along its length; either no well defined interstitial lines or line 3 may be defined; elytral carina absent; in horizontal specimen viewed from below epipleuron at elytral base wide, covering or almost covering humerus; viewed from above the anterior margin of the epipleuron arises anterior to or level with posterior margin of MS; epipleuron developed as a lateral ridge along most of length.

Head: shallowly to moderately depressed between eyes; 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 ill defined, rounded, without median elevation; posterolateral eye excavation not developed; antennal sockets on head between eyes, not contiguous, separated by <or> 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 strongly flattened, of form of a wide triangle (widest at base and L 2– 3 X W), with inner edge dentate (number of teeth may differ from left to right palp in the one individual) 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 ( Figs 2 , 7 , 18 , 19 , 20 ): with inner tarsal claw not split; without MFC; no femora or tibiae swollen or curved; no basitarsi expanded or excavated.

Abdomen ( Figs 2 , 7 , 18 , 19 , 20 ): 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 all V7, reaching almost to sides, except for a very narrow lateral and sometimes a narrow posterior margin, V7 remaining flat, sides not curving upwards, in almost all specimens examined; posterior half of V7 not arched or swollen; neither anterior nor posterior margin of LO emarginate; LO occupying all V6. MPP not developed. 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 broadly rounded, without PLP. T7 without prolonged anterolateral corners. T8 well sclerotised, symmetrical, L>W, visible posterior area not narrowing abruptly, median posterior margin not emarginate exept in some pinned specimens; without prolonged posterolateral corners, median posterior projections, not extending conspicuously beyond posterior margin of V7; posterior margin not engulfing posterior margin of V7 nor MPP; T8 ventral surface without median longitudinal trough, lateral depressed troughs, asymmetrical projections, median posterior ridge; concealed anterolateral arms of T8 longer than 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 ( Fig. 3 A, B; Fig. 10 A, B; Fig. 23 A, B; Fu & Ballantyne 2008 Fig. 19 ): 2.5–2.7 times as long as wide; without bulbous paraprocts; sternite narrowing anteriorly with a rounded anterior margin, and expanding evenly posteriorly, posterior area about 2– 3 x as wide as anterior narrow section; median dorsal surface of sternite without ridge; sternite shorter than tergite, with the wider rounded posterior margin bearing paired lobes the shape of which is diagnostic for certain species; tergite of sheath projecting both behind sheath sternite and at sides beyond lateral margins of sternite, with narrow lateral well sclerotised arms lying beside the sternite and joining to its sides in its anterior half; posterior margin of sheath tergite broadly and usually deeply emarginate, anterior margin evenly emarginate; in Abs. cerata a transverse cuticular strip (in two pieces) is associated with the anterior margin of the tergite attached by membrane to the sides of the sheath and not dislodged on dissection and subsequent clearing of the specimen (Fu & Ballantyne 2008 Fig. 19 ).

Aedeagus ( Fig. 3 C, D, E; Fig. 10 C, D, E; Fig. 19 F; Fig. 23 C, D, E; Fu & Ballantyne 2008 Fig 20 ): Length/ width 2–2.5; width across LL/ML at base 3/1); BP well sclerotised with inner margin concave; LL visible to either side of the ML from below, with fleshy cylindrical appendages arising from the ventral surface near their edges; LL subparallelsided along their outer margins and aedeagus not conspicuously narrower across its posterior 1/3; essentially symmetrical; dorsal base of LL slightly asymmetrical; LL fused along most of their length dorsally, and widely separate in apical 1/6; area of LL joining ML along mid-dorsal line wide and well sclerotised (Fu & Ballantyne 2008 Fig. 20 B); junction of this area and the oblique ridges (junction C, oblique ridges D in Fu & Ballantyne 2008 Fig. 20 ) being part of inner posterior margin of the LL and projecting a little; from the side these being strong bluntly pointed areas (arrow in Fu & Ballantyne 2008 Fig. 20 ); area D delimited by the oblique ridges on the ventral surface of each LL an elongate wide subtriangular area, fleshier than the rest of the base, and bearing inside the inner margins of the LL paired, hairy, apically rounded cylindrical lobes. ML symmetrical, narrower at its bluntly rounded apex and at least twice as wide in basal half as apical half; ML almost as long as, or very slightly longer than LL, with a truncate base and articulating with the inner surface of the bases of the LL (Fu & Ballantyne 2008, Fig 20 A).

Female ( Fig. 2 C, D; Fig. 7 C, D; Fig. 18 D, E, F; Fig. 19 D, E). Macropterous and observed in flight in some species. Pronotal outline similar to that of male; 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 occupying all of V6; without any elevations or depressions or ridges on V7; median posterior margin of V7 emarginate often deeply; median posterior margin of V8 narrowly emarginate. Bursa plates in form of short hooks.

Larva ( Figs 2 E; Fig.13 A; Fig. 20 D, E; Fig. 26 B). Associated by breeding for certain species; terrestrial; with 3 thoracic and 10 abdominal terga, similar to larvae of Pygoluciola qingyu (Fu & Ballantyne 2008) with the exception of larvae of Abs. anceyi , which have numerous very short spines over the surface.

Body: tergal plates not narrowly explanate, however margins thickened and laterotergites often not visible at sides of body when viewed from above; dorsal body with heavily sclerotised plates bearing numerous short spines; all tergal plates except the last with four short narrow apically pointed projections along posterior margins (in anceyi the posterolateral projections are rounded in the thorax and pointed in the abdomen); exposed membranous areas on dorsal surface only visible between expanded segments; protergum and remaining terga except terminal tergum with raised uneven median line often not reaching either to anterior or posterior margins; protergum longer than wide, with median anterior margin rounded and slightly ridged, lateral margins slightly convex sided, converging slightly towards posterior margin except in anceyi where the lateral margins diverge posteriorly and bear four rounded projections in the posterior half; posterior margin medianly shallowly emarginated; anterolateral corners of terga 2, 3 straight and obliquely truncated except in anceyi where there is a short rounded projection; lateral margins subparallel-sided, posterolateral corners narrowed and produced except in anceyi where the lateral margins have 3 rounded projections; tergum 3 longer than 2; anterolateral corners of abdominal terga 1–8 with obliquely truncated anterolateral areas (which may not be visible if segments retracted), and subparallel sides except in anceyi where there are 2 elongate slender projections at the posterolateral corners; terminal tergum with sides subparallel; ventral body not heavily sclerotised, flexible, most abdominal plates coloured; arrangement of ventral surface conforming to that described for Pteroptyx valida Olivier (Ballantyne & Menayah 2002) viz.: 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 sterna 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); no eversible abdominal structures bearing glands.

Head ( Figs 4 , 12 , 25 ): Antennal segment 3 elongate, surmounted by several hairs, longer and thinner than adjacent sense cone; apex of segment 2 strongly oblique.

Mouthparts ( Figs 4 , 12 , 25 ): Mandibles with single toothed retinaculum except in anceyi where there are two apically rounded teeth ( Fig. 4 A), most of dorsal surface smooth, not ridged; single line of thick stout setae just inside lateral margin on dorsal surface, setae not appearing split at apices; outer edge of mandibles bearing hairs along most of margin. Maxillae: apical palpomere elongate, narrowing at rounded apex, with terminal sense organs. Labium: palpi widely separated at their bases; apical palpomere elongate, narrowing at rounded apex, with terminal sense organs; prementum wider than long, with ventral surface largely hairless.

Legs: without brush of hairs from apex of tibiotarsus.

Etymology. Abscondita is regarded as a feminine noun, derived from the Latin adjective absconditus, a, um meaning covert or disguised. The name was chosen to reflect the difficulty authors have had historically in the correct identification of certain of the species included here which bear similar dorsal colouration of pale brownish yellow and dark elytral apices (see Table 1).

Remarks. This new genus is most closely related to some Pygoluciola Wittmer (see Fig. 1 ).

Figures

FIGURE 1. The medial section of the Majority rule tree, consensus of 169 MPT of length 5609 from phylogenetic analysis of 143 taxa and 436 morphological characters in Fu et al. (2012) showing Luciola sensu stricto and Abscondita gen. nov., and % of MPTs with the node. For those nodes found in 100 % of MPT, the % is shown in bold. Many nodes are numbered (35 to 55) in red, bold italics. A selection of terminal branches are numbered (15 to 21) in blue, bold italics. Modified from Figure 8 (Fu et al. 2012).

FIGURE 2. Habitus Abscondita anceyi. A, B male; C, D female; E larva (A, C, E dorsal; B, D ventral) (Scale bar = 5 mm).

FIGURE 3. Abscondita anceyi male genitalia. A, B aedeagal sheath; C, D, E aedeagus (A, C dorsal; B, D ventral; E left lateral) (Scale bar = 1 mm).

FIGURE 4. Abscondita anceyi fifth instar larva SEM. A, B, C head; D antenna, terminal three segments (A dorsal; B, D ventral; C anterior, dorsal surface uppermost).

FIGURE 7. Habitus Abs. chinensis. A, B male; C, D female; E, F larva (A, C, E dorsal; B, D, F ventral) (Scale bar = 5 mm).

FIGURE 10. Ab. chinensis male genitalia. A, B aedeagal sheath; C, D, E aedeagus (A, C dorsal; B, D ventral; E right lateral) (Scale bar = 1 mm).

FIGURE 12. Abs. chinensis fifth instar larva SEM. A, B, C head; D antenna; E apex apical maxillary palpomere; F apex galea and apex maxillary palpomere (to right). (A dorsal, anterior half of head only; B, anterior dorsal surface uppermost; C, D, E, F ventral; C anterior half of head only).

FIGURE 13. Abs. chinensis life history. A Larvae feeding on body of dead ant Polyrhachis vicina; B pupal cell; C Male feeding on flower of pomegranate Punica granatum; D male and female in copulo.

FIGURE 18. Luciola perplexa Walker A, B (type male NHML). Luciola dubia Olivier C, D (type male NHML), E, F female (NHML). A, C, E dorsal; B, D, F ventral.

FIGURE 19. Luciola aegrota Olivier A, B, C, F, G (syntype male MCSN). Luciola promelaena (Walker) D, E (type female NHML). Locality labels H, I. A, C, D, dorsal, B, E ventral whole body; F aedeagus ventral; G dissected abdomen ventral.

FIGURE 20. Habitus Abscondita terminalis. A, B male; C female; D, E larva; F male pupa (A, D dorsal; B, C, E, F ventral) (Scale bar = 5 mm).

FIGURE 23. Abs. terminalis male genitalia. A, B aedeagal sheath; C, D, E aedeagus (A, C dorsal; B, D ventral; E right lateral) (Scale bar = 1 mm).

FIGURE 25. Abs. terminalis fifth instar larva SEM. A, B, C head; D part of labium, maxilla and left antenna; E larva. (A anterior view slightly to one side with ventral surface uppermost; B, E, dorsal; C, D ventral). A 1 antennal segment 1; A 2 antennal segment 2; A 3 antennal segment 3; SC sensory cone; LP labial palp; G galea; MXP maxillary palpus.

FIGURE 26. Abs. terminalis life history. A observation site-paddies (Red flag village, Wuhan city); B larvae feeding on termites Reticulitermes chinensis; C pupal cell; D male and female in copulo.