Eneopterinae crickets (Insecta, Orthoptera, Grylloidea) from Vanuatu

Robillard T. 2009. — Eneopterinae crickets (Insecta, Orthoptera, Grylloidea) from Vanuatu. Zoosystema 31 (3): 577-618. ABSTRACT The present study deals with the Eneopterinae crickets from Vanuatu, in particular from Espiritu Santo Island. Seven new species are described: Cardiodactylus aobaensis n. sp., C. epiensis n. sp., C. pentecotensis n. sp., C. tankara n. sp., Lebinthus santoensis n. sp., L. nattawa n. sp., L. malekulensis n. sp., and two are redescribed (C. cheesmani Otte, 2007 and C. enkraussi Otte, 2007). Descriptions focus on male and female genitalia, and forewing venation, while data are presented to define fine-scaled habitat, behaviour, and song repertoires.

In Vanuatu, these crickets are abundant both in primary forests and secondary habitats (gardens, cultures, edges, costal areas). Th ey are represented by two genera of the tribe Lebinthini Robillard, 2004: Cardiodactylus Saussure, 1878and Lebinthus Stål, 1877(Robillard & Desutter-Grandcolas 2004a. Th e Lebinthini are widely distributed throughout Melanesian archipelagos, in South-East Asia, Northern Australia and New Caledonia (Desutter- Grandcolas & Robillard 2006;Otte 2007a). Th ey occupy an important part in the acoustic diversity of Eneopterinae, with originalities laying mainly in the spectral properties of their songs. Based on the analysis of the frequency spectra of the calling song in reference to phylogeny, previous studies showed that Lebinthini use high frequencies for calling (Robillard & Desutter-Grandcolas 2004b). Strikingly, whereas crickets usually call with dominant frequencies corresponding to the fundamental frequency, the high frequencies dominating Lebinthini's calling are corresponding to the second or third harmonic (Robillard et al. 2007).
To better understand the evolution of these unique acoustic features, basic data are needed for as many species as possible, which in turn necessitates taxonomic and biological studies. In this paper I analyse the crickets Eneopterinae from Vanuatu, which were known by only a few old specimens without information about biology, acoustics and habitats. Th e focus is given to Espiritu Santo Island, which was extensively sampled during the SANTO 2006 Expedition (see Desutter-Grandcolas 2009 andHugel 2009, this volume). Four new species of Cardiodactylus and three of Lebinthus are described from the archipelago, and two species are redescribed, focusing on male and female genitalia and forewing venation. Data are provided on fi ne-scaled habitat (Tables 1; 2), behaviour, and song repertoires. Th e biological information allows a precise description of the species' life habits, and the study of life habit evolution (Grandcolas et al. 2001).

MATERIAL
Extensive fi eldwork was made in many localities in Espititu Santo with Laure Desutter-Grandcolas and Sylvain Hugel, within the "Forests, Mountains, Rivers" theme of SANTO 2006 Expedition. For a narrative of the expedition, see Bouchet et al. (2008). A review of the geography and natural history of Santo will be published by Bouchet et al. (in press). Specimens were collected by sight only, by night and day, in order to observe their precise habitat and type of activity. Th e collected specimens are deposited in the MNHN collections. Reared specimens (generations F1-F2) are also deposited in MNHN collections when associated to acoustic and/or behavioural data. Political districts and island within Vanuatu are mentioned for every specimen within lists of material, square brackets are used for additional information not mentioned on specimen labels.

MALE TEGMINAL VENATION
Male tegminal veins and cells ( Fig. 1) are named after Desutter- Grandcolas (2003) for Ensifera and Robillard & Desutter-Grandcolas (2004a) for the subfamily Eneopterinae more specifi cally. FW dorsal fi eld shows strong longitudinal veins and weaker transverse ones. Th e three/four most inner longitudinal veins are the distal parts of 1A-4A (abbreviations, see below); the others originate from CuA and are called CuA1 to CuAi, from the most basal to the most distal ones, and each pair of successive longitudinal veins delimit a cell alignment (A, B, C…).

MALE AND FEMALE GENITALIA
Male and female genitalia have been dissected in softened specimens by cutting the membranes between (1 F, 2 Ct, 5 Cl), 9 ( 2 Ct  the paraprocts and the subgenital plate or between the ovipositor and the subgenital plate respectively; they have been observed after cleaning with cold KOH using a binocular magnifying glass Leica MZ16, at magnifi cation up to 160, and then kept in glycerine in vials pinned under studied specimens. Male genitalia are named according to Desutter (1987), modifi ed in Desutter- Grandcolas (2003) and Robillard & Desutter-Grandcolas (2004a). Dotted parts correspond to membranous areas.
Abbreviations: see below.
ACOUSTIC DATA Th e basic cricket song terminology follows Ragge & Reynolds (1998). One song unit is called a syllable and corresponds to one opening-closure cycle of the male forewings; a repeated group of syllables is called an echeme and corresponds to the calling unit of a species; a series of echemes constitutes a phrase. Cardiodactylus enkraussi Otte, 2007, C. tankara n. sp. and L. santoensis n. sp. were studied in the fi eld and subsequently in the laboratory. Th e recordings were made with a Condenser Microphone Capsule CM16, with a fl at frequency response from 5 to 250 kHz (R. Specht pers. comm.), connected to a TASCAM HD-P2 digital recorder (96 kHz sampling frequency, 16 bit). Acoustic analyses were performed using the computer software Avisoft-SASLab Pro version 4.40 (Specht 2008) and Seewave version 1.4.6 (Sueur et al. 2007(Sueur et al. , 2008, a custom-made library of the "R" software platform (R Development Core Team 2004). Song features were measured using the automatic commands under Avisoft-SASLab Pro for fi ve specimens per species. Mean values and standard deviation per individual and per species were calculated after adjustment for a common recording temperature of 25°C. All recording fi les have been deposited in the Sound Library of the Muséum national d'Histoire naturelle, Paris.
DISTRIBUTION. -Vanuatu, Espiritu Santo Is. and Malekula Is. Otte (2007a) also mentions specimens from Eromango Is. but none could be examined in the present study.
DIAGNOSIS. -Size rather small, body slender, general colouration dark brown to grey brown, quite homogeneous with a characteristic two-part calling song with low intensity compared to that of C. novaeguineae and C. tankara n. sp. Species very similar to C. pentecotensis n. sp. (see below), but diff ering by male genitalia (endophallic sclerite).
Male FW (Fig. 1A : pseudepiphallus narrowed at midlength, with a large dorsal concavity and a narrow median process, slightly setose basally, concave dorsally, its apex spoon-like and more or less rounded. Pseudepiphallic parameres trilobate, a narrow divergent lobe fused with lateral membrane and two inner ventral lobes of variable shape. Membrane between base of para-meres and ectophallic arc with a sclerite oriented posteriorly, forming wide membranous structures. Ectophallic arc complete and straight, anterior to parameres, with a median posterior expansion. Ectophallic apodemes variable in shape, not reaching rami apex. Apex of ectophallic fold between pseudepiphallic parameres, trilobate, the median lobe sponge-like, possibly glandular. Endophallic sclerite small, V-shaped, with a medio-posterior expansion. Endo phallic apodeme made of a large medio-dorsal crest extended anteriorly. Membrane of endophallic cavity fi nely and transversally plicate.

Juvenile
Colouration variable from yellowish brown to dark brown, dorsum and femora more or less mottled with dark brown, tibiae with dark bands; lateral sides and sternites black, except a median yellow stripe. Head dorsum with same colouration as in adults; face dark brown to black with yellow patterns.

Measurements
See Table 3. Robillard T. HABITAT AND LIFE HISTORY TRAITS In Espiritu Santo, C. enkraussi lives in forested areas ( Fig. 17A) together with C. tankara n. sp. (Butmas area) or C. novaeguineae (coastal areas), although in less conspicuous places.
Individuals are found deep in vegetation, on between large leaves, on stems, bushes or low trees, between 30 cm and 3 m in height. Th e species is active at night only, but some specimens are found in leaf litter by day, from where they escape by jumping and fl ying. At night, groups of specimens gather on plants in relatively dense populations (Tables 1; 2).

BEHAVIOUR
Calling song (Fig. 14; Table 4) Males call from dusk to late at night, staying deep within vegetation, on leaves or branches. Th e calling song of C. enkraussi is less conspicuous than that of C. novaeguineae and C. tankara n. sp. Th e songs of fi ve males recorded in the fi eld (TR-330, TR-331, MNHN-ENSIF2363, 2325) and in the laboratory (spec-El-3 [MNHN-ENSIF2404], El-4 [2405], El-7) at 22-26.5°C are analysed here. At 25°C, the call consists of irregular song phrases (mean phrase duration ± SD = 28.9 ± 2.6 s). Each phrase generally begins with a series of 28 ± 10, low amplitude, single echemes, followed by a series of 22 ± 2 more intense double echemes subdivided into two sub-echemes by an interval of 174 ± 23 ms, and/or by 1 to 3 intermediate syllables (m = 2.13 ± 0.45) sometimes joining the two sub-echemes.
Th e dominant frequency of C. enkraussi is the third harmonic of the song (single echeme: 19.5 ± 0.6 kHz) (Robillard et al. 2007). Within the double echemes, the dominant frequency is slightly higher in syllables of DE2 (20.3 ± 0.9 kHz) than in DE1 (19.6 ± 0.7 Hz).

Courting song
Th e courting song is less intense than the calling song but similarly composed of single and double echemes unevenly arranged; series of one component sometimes repeated during several minutes without a clear phrase structure.

Aggressive song
Aggressive interactions between males were not observed despite many attempts in laboratory. Th is song could be absent from the repertoire of C. enkraussi.  ETYMOLOGY. -Species named after the type locality.
DIAGNOSIS. -Species very similar to C. enkraussi in shape, size and colouration, homogeneous brown, but separate by male and female genitalia. Th e main diff erence between the two species is the wider shape and larger size of the endophallic sclerite in C. pentecotensis n. sp., the lateral arms of the sclerite being in continuity with the ectophallic fold sclerotization in C. pentecotensis n. sp. but not in C. enkraussi.
Female genitalia ( Fig. 7D-F): same general shape as C. enkraussi, but apex more protruding, and ventral bump narrower, with a median ventral sclerotized expansion.

Measurements
See Table 5.
HABITAT, LIFE HISTORY TRAITS AND BEHAVIOUR Not documented.

Novaeguineae group (Otte 2007a)
Cardiodactylus novaeguineae (Haan, 1842) (Table 1). Juveniles commonly gather on the same plants and are sometimes found in the leaf litter, while adults are generally more spaced from one another (Tables 1; 2). Foraging occurs from afternoon to night and no diff erence was observed in positioning between day and night, either for adults or juveniles.

Calling song
Males call from dusk to late at night, but a few males were heard calling earlier during afternoon by cloudy days. Th e calling song consists of irregular phrases including single or two-part echemes (see Robillard & Ichikawa [in press] for measurements). For analysed songs, the dominant frequency is 15.8 ± 0.5 kHz at 25°C and corresponds to the third harmonic of the song (Robillard et al. 2007); the mean fundamental frequency is about three times lower (5.3 ± 0.2 kHz).

Courting song
Th is song is less intense than the calling song. It has similar long-syllable and short-syllable components as the calling song, but unevenly arranged, with series of one component sometimes repeated during several minutes.

REDESCRIPTION
In addition to the characters given by Otte (2007b) as wide, median ocellus yellow. Pronotum: dorsal disk trapezoidal, slightly bisinuated posteriorly. Fore tibiae not widened at tympana level. Hind tibiae dorsal face with 6 inner and 14 outer spines above spurs, 4 inner and 10 outer spines between spurs (n = 1). Tarsomeres III-1 with 4 spines on dorso-external edges (n = 1). FWs slightly longer than abdomen; hind wings forming a short grey brown tail about 1.5 times as long as pronotum. Cerci homogeneously brown.

Measurements
See Table 6   DIAGNOSIS. -Species close to Cardiodactylus cheesmani but diff ering by colouration darker. Size average, larger than C. enkraussi, shape more stocky than C. novaeguineae (Figs 8; 17E). Male FW generally without a clear light crescent including posterior part of mirror; male genitalia close to that of C. cheesmani, but diff ering by the shape of the pseudepiphallic sclerite (dorsal crest asymmetrical, basal protuberance near median shrinkage).

DESCRIPTION
Size average, stocky shape. General colouration dark brown, a few specimens lighter, with contrasted yellow or whitish patterns on dorsum and face. Scapes whitish with two dark brown spots, on inner sides and face; antennae homogeneously brown basally and including light areas. Head dorsum with 3 wide dark brown bands, bordered by a thin band behind eye and a yellow line more externally. Fastigium twice as long as wide, dark brown posteriorly, its apex yellow around dark median ocellus. Face with two more or less distinct dark brown curved patterns diverging from front head to below antennae. Mouth parts yellowish, separated from the face by a black line, highlighted by a horizontal yellow band. Palpi whitish, apex darker. Pronotum: dorsal disk trapezoidal, slightly bisinuated posteriorly; dark brown mottled with grey brown and sometimes with whitish, but generally little contrasted. Lateral lobes dark brown to grey brown near dorsal angle; ventral edge whitish. Legs yellowish brown, femora more or less mottled with brown; tibiae more or less banded. Fore tibiae not widened at tympana level. Hind tibiae dorsal face with 6-8 inner (m = 7, n = 8) and 12-15 outer (m =14, n =8) spines above spurs, and 5 or 6 inner (m = 6, n = 8) and 9 or 10 outer (m = 10, n = 8) spines between spurs. Tarsomeres III-1 with 2-6 spines on dorso-external edges (m = 3, n = 8). Hind wings longer than FWs, but proportionally shorter than in C. enkraussi, forming a dark brown tail 1.5 times as long as pronotum. Cerci dark brown, banded but little contrasted.  Mirror area variable, c1 long and narrow, c2 quite large; mirror (d1) longer than wide, not rounded, its shape prolonged by d2 and separated at second third by one or several accessory veins. Apical fi eld short, triangular, CuA with 2 or 3 bifurcations posterior to mirror. Lateral fi eld (Fig. 1D): latero-dorsal angle made by MP. R with 8 bifurcating veins. Male genitalia (Fig. 4F-H): close to C. cheesmani and C. guttulus (Matsumura, 1913) (Robillard & Ichikawa in press). Pseudepiphallus very sclerotized and setose, slightly narrowed at midlength with a basal protuberance absent in C. cheesmani. Two parallel dorsal ridges, forming a gutter, their dorsal edges asymmetrically folded externally, the left one being shorter and widened in all examined males (n = 7; Fig. 4G). Pseudepiphallic sclerite extended laterally anterior to the ridges, but without a membranous sac as in C. novaeguineae. Apex of pseudepiphallus spoon-like and rounded, not separate from the rest of pseudepiphallus, its profi le diff ering from C. cheesmani. Rami large, their base at level of pseudepiphallus narrowed part. Pseudepiphallic parameres trilobate, large and close together. Membrane at base of parameres sclerotized. Ectophallus almost hidden within the pseudepiphallus. Ectophallic arc complete, anterior to parameres. Ectophallic apodemes almost reaching rami apex. Apex of ectophallic fold almost hidden by pseudepiphallic parameres, trilobate, the median lobe sponge-like, possibly glandular, shorter than lateral lobes. Endophallic sclerite small, without a medio-posterior expansion. Endophallic apodeme with both lateral lamellas and a short medio-dorsal crest. Membrane of endophallic cavity fi nely and transversally plicate. Ovipositor: Shorter than hind femora; apex with both dorsal and ventral edges denticulate, more pronounced on ventral valve (Fig. 6B).

Juvenile
First instars observed in laboratory similar to that of C. novaeguineae, yellow with brown longitudinal bands. Later instars with more contrasted colouration, dark brown to black highly mottled with whitish and yellow. Head colouration as in adults, the head dorsum and face sometimes entirely black. Pronotum as in adults, sometimes more contrasted. Metanotum and tergites with median, paired black patterns; rest of abdomen dorsum brown with dark brown dots disposed in longitudinal lines.
Measurements See Table 7. HABITAT AND LIFE HISTORY TRAITS Cardiodactylus tankara n. sp. lives in dense forested areas but is also found near borders and in open areas (Fig. 17D, E). Individuals are found on large leaves of trees, bushes of fern and creepers, or on tree trunks (including Pandanaceae) at about 2 m height. Singing males are distributed at relatively large distance from one another (Tables 1; 2). Cardiodactylus tankara n. sp. is sympatric with C. enkraussi at the plateau of Tankara. Th e population density is comparable to that of C. novaeguineae, and contrasts from the denser populations of C. enkraussi.

BEHAVIOUR
Mating behaviour not observed.
Calling song ( Fig. 15; Table 8) Males of C. tankara n. sp. are mostly acoustically active at night, but have been heard singing during daytime. Th e calling song is more conspicuous and noisy than that of sympatric C. enkraussi. Six males recorded in the fi eld at 20-26°C (MNHN-ENSIF 2409, 2411, 2412, 2418, 2419, 2421) are analysed here. At 25°C, the calling song consists in an irregular succession of short echemes (mean echeme duration ± SD = 162 ± 7 ms; period = 2538 ± 1118 ms; duty cycle = 6.9 ± 0.7%; echeme rate = 26.3 echeme/min). Th e echeme is slightly accelerated from start to end (regular decrease of syllable period within echeme) and shows a crescent amplitude profi le. Each echeme is made of 27.5 ± 2.1 syllables with the following characteristics: syllable rate = 170.8 ± 2.1/s; syllable duration = 1.2 ± 0.4 ms; syllable period = 6.2 ± 3.6 ms; syllable duty cycle = 19.5%; and each echeme is fi nished by a longer syllable, which is likely the contraction of 3 or 4 syllables (mean duration = 4.8 ± 1.9 ms). Th e calling frequency of C. tankara n. sp. is relatively high (14.3 ± 0.4 kHz), and corresponds to the third harmonic of the song (Robillard et al. 2007); the mean fundamental frequency is 5.6 ± 0.2 kHz.

Courting song
Th is song was observed during forced interactions with females of C. novaeguineae; it is less intense than the calling song, but the echeme is similar to the calling song, except for its irregular period.

Aggressive song
Th is song was observed in laboratory during interactions between two singing males of C. tankara n. sp. After alternating their songs, one male sometimes charges the other one and sings more frequently in front of him. Th is aggressive song is quite similar to the calling song but of shorter duration and period.

DESCRIPTION
Large species for the genus, the largest one for Vanuatu, stocky shape. General colouration light brown, little contrasted. Scapes yellow with two dark brown spots, on inner and facial sides. Head dorsum almost entirely brown, with a median suture yellowish; yellow behind eye, with a transverse brown line posterior to eye. Fastigium 1.5 times as long as wide, median ocellus yellow. Face yellowish brown with two dark brown curved patterns diverging from front head to below antennae. Palpi yellowish brown, apex darker. Pronotum: dorsal disk trapezoidal, slightly bisinuated posteriorly; brown, with a thin longitudinal median yellow line, and lateral yellow bands interrupted at midlength by transverse dark brown bands. Lateral lobes of pronotum dark brown near dorsal angle; ventral edge progressively lighter. Legs light brown, fore and mid legs faintly spotted with dark brown, knees of mid legs dark brown. Fore tibiae not widened at tympana level. Hind tibiae dorsal face with 7 inner and 13 outer spines above spurs, with 7 inner and 8 outer spines between spurs. Tarsomeres III-1 with 4 spines on dorso-external edges. FWs much longer than abdomen; hind wings proportionally shorter than in C. enkraussi, making a dark brown tail 1.5 times as long as pronotum. Cerci brown, darker at apex.

Male
Unknown.
Female FW colouration (Fig. 5C) as wide, median ocellus yellow. Head dorsum with 6 wide dark brown bands and 2 yellow bands behind eyes. Face with a yellow band above clypeus; 2 dark brown curved patterns diverging from front head to below antennae. Pronotum: dorsal disk trapezoidal, slightly bisinuated posteriorly; lateral lobes dark brown except ventral margin whitish.

DESCRIPTION
Species of small size. Colouration (Figs 9; 18E, F) most often light brown dorsally and darker ventrally, with more or less contrasted colour patterns. Head dorsum light brown with 6 more or less visible longitudinal bands, 2 median ones, patchy at level of fastigium, next 2 lateral ones curved externally toward eyes midlength, 2 most external ones behind eyes. Some specimens with almost completely light brown or dark brown head dorsum with faint banded patterns. Eyes light brown dorsally, dark brown to black ventrally. Fastigium slightly wider than long, setose, whitish brown with a dark spot behind whitish median ocellus. Scapes whitish, antennae homogeneously brown. Face with 2 diverging black curved lines between antennae, with a median black triangle above clypeus; black areas bellow antennae; these elements more or less separated or fused according to specimen general melanisation. Mouth parts dark brown to black. Palpi whitish, banded with dark brown. Pronotum: Dorsal disk almost rectangular, straight posteriorly; light brown, whitish laterally, most often with dark spots arranged in uneven lines. Lateral lobes black except for whitish ventral margin, sometimes partly brown. Legs: fore and mid femora with large dark brown to black spots, fore and mid tibiae banded; fore tibia not widened at tympana level. Hind femur brown, with striated light patterns on external face, 3-5 black spots on each ventral edge, knees dark brown; distal half of hind tibiae and tarsomeres III-1 black. Hind tibiae dorsal faces with 5-9 inner (m = 6, n = 10) and 8-13 outer (m = 10, n = 10) spines above spurs, and 3-5 inner (m = 4, n = 10) and 2-5 outer (m = 5, n = 10) spines between spurs.
Tarsomeres III-1 with 4 spines on dorso-external edges (n = 10). Hind wings absent, FWs short. Abdomen brown, with a black or dark brown band on each lateral side; each tergite with dark spots on posterior margin. Cerci homogeneously brown, dark brown at base ventrally, with a preapical black ring, unlike L. lifouensis.

Female
FWs short (Fig. 11A), exceeding posterior margin of fi rst tergite, separated by a distance equal to length; dorsal fi eld with 4 or 5 strong longitudinal veins, whitish or brown. Lateral fi eld darker than dorsal fi eld, with 3 or 4 strong dark brown longitudinal veins. Ovipositor short; apex lanceolate, denticulate on dorsal edge.
Female genitalia: copulatory papilla ( Fig. 12A-C) with small basal sclerotized ring; apex narrowed and long, with a ventral bump.

Juvenile
Colouration generally more contrasted than adults, with a pair of dark brown patterns on fi rst tergites (Fig. 18F).

Measurements
See Table 11.
HABITAT AND LIFE HISTORY TRAITS Lebinthus santoensis n. sp. lives in leaf litter in open forested areas in coastal areas, near river banks or along beaches (Fig. 18A, B). It is found in dense populations in wet leaf litter, generally on or under large dead leaves (Tables 1, 2; Fig. 18C, D).

BEHAVIOUR
Mating behaviour has been observed in laboratory (TR, 2006(TR, -2008; multiple copulations have been recorded (2-6 copulations, n = 2); between each copulation (c. 45-60 min) the male actively guards the passive female by singing almost constantly starting a few minutes after removal of previous spermatophore by the female.
Calling song (Fig. 16;Table 12) Males start singing during the afternoon from within the leaf litter, but are fully active at night, mostly on top of leaf litter. Five males recorded in the fi eld (MNHN-ENSIF2483, 2503, 2507 and in laboratory (MNHN-ENSIF2551, 2553) at 23-29°C are analysed here. At 25°C, the calling song consists of a continuous succession of two-part echemes separated by a short silence of 1.1 ± 0.4 s (mean echeme duration = 26.2 ± 9.7 s; period = 27.3 ± 10.1 s): each echeme starts by a slow trill, made of 42 ± 9.7 widely spaced syllables, followed by a fast trill (mean trill duration = 11.9 ± 0.6 s; period = 26.7 ± 3.0 s; fast trill/slow trill duty cycle = 45.3 ± 17.7%; fast trill rate = 2.24/min) made of 463.9 ± 27.3 syllables. All syllables are amplitude modulated; syllables of slow trill have the following characteristics:  (Robillard et al. 2007); mean fundamental frequency is about twice lower (13.3 ± 0.8 kHz). Th e dominant frequency of L. santoensis n. sp. is the highest known so far for crickets (Robillard et al. 2007), and this feature constitutes the clearest criteria to distinguish this species from L. lifouensis, for which spectral pattern is similar, but with twice lower frequency values (dominant frequency = 12.6 kHz; fundamental frequency = 6.3 kHz) (Robillard et al. 2007).

Courting song
Th is song is less intense than the calling song but similar in temporal pattern.

Intercopulatory song
Th is song is similar to the calling song but less intense; the slow part of the song is more intense than the echeme, and the syllables are more indented than in the calling song. Th is song is almost continuous and starts a few minutes after removal of previous spermatophore by the female.
DIAGNOSIS. -Species of small size, close to L. santoensis n. sp. and L. lifouensis from which it diff ers by male genitalia and female copulatory papilla, wider and of more stocky shape (pronotum wider), and colouration dark brown dorsally and darker ventrally, with same dark apical ring on cerci.
DESCRIPTION Species of small size, shape wider and more stocky than in L. santoensis n. sp. Colouration most often dark brown dorsally and darker ventrally (Figs 13;19B,C). Head dorsum with 6 more or less visible dark brown longitudinal bands, sometimes with almost completely brown head dorsum, with faint band patterns still visible. Eyes light brown dorsally, dark brown to black ventrally, the dorsal margin with a dark brown area, thinner or absent in L. santoensis n. sp. Fastigium brown, wider than long and setose, apex whitish with a dark spot behind median ocellus. Scapes light brown, antennae homogeneously brown. Face almost entirely black, except a median yellow line on fastigium. Mouth parts dark brown to black. Palpi light brown, banded with black. Pronotum: Dorsal disk trapezoidal, wider posteriorly than in L. santoensis n. sp.; posterior margin straight; light brown with dark spots arranged in uneven lines; lateral lobes of pronotum almost entirely black, with a partial whitish band near ventral third, ventral margin whitish. Legs: colouration as in L. santoensis n. sp., but generally darker. Hind tibiae dorsal face with 4 or 5 inner (m = 5, n = 8) and 7 or 8 outer (m = 7, n = 8) spines above spurs, and 4 or 5 inner (m = 5, n = 8) and 5 outer (m = 5, n = 8) spines between spurs. Tarsomeres III-1 with 3-5 (m = 4, n = 8) spines on dorso-external edges. Hind wings absent, FWs short. Abdomen wide, brown with a black band on each lateral side; each tergite with dark spots on posterior margin. Cerci light brown, entirely banded, including a preapical black ring, as in L. santoensis n. sp.

Male
FW not reaching abdomen midlength (Fig. 13). FW colouration (Fig. 1G, H): dorsal fi eld homogeneously dark brown, except MP/MA area greyish; lateral fi eld brown, MA/R area dark brown; veins slightly lighter than cells. FW venation similar to L. santoensis n. sp.: 1A angle wide (>130°); stridulatory fi le with 149 teeth (n = 1), located on both transverse part (117 teeth) and angle (32 teeth) of 1A (Fig. 3D). CuP missing. Harp as wide as long, with one harp vein parallel to transverse axis. CuA curved internally at apex, the median fold triangular and short, located on dorsum. Cell c1 wider than in L. santoensis n. sp., separated at midlength by an accessory vein, c2 large. Mirror triangular, without accessory vein and larger than in L. santoensis n. sp.; d2 thin and rectangular. Apical fi eld almost absent, including only 2 cells behind mirror (E alignment). Lateral fi eld with 6 strong longitudinal veins including MA, R and 4 more ventral veins; latero-dorsal angle made by MP; R without strong bifurcations.
Female FW dark brown, shorter than in L. santoensis n. sp., not reaching beyond posterior margin of fi rst tergite, separated by a distance equal to length (Fig. 11B); dorsal fi eld with 4 or 5 strong longitudinal veins. Lateral fi eld with 3 or 4 strong longitudinal veins. Ovipositor short; apex lanceolate, denticulate on dorsal edge (Fig. 6H). Female genitalia: copulatory papilla (Fig. 12D-F) widened dorsally, more elongate than in L. santoensis n. sp., its basal sclerotized ring irregular; apex narrowed and long, curved ventrally, with a preapical ventral bump.

Juvenile
Subadults similar to adults in colouration.

Measurements
See Table 13.
HABITAT AND LIFE HISTORY TRAITS Lebinthus nattawa n. sp. lives in leaf litter in forested areas (Fig. 19). Specimens are found in dense populations in wet leaf litter, generally on or under large dead leaves. Robillard T. DIAGNOSIS.
-Species of small size, dark brown general colouration, very similar to L. santoensis n. sp. and L. lifouensis in size, shape and colouration patterns. Dark ring on cerci apex present as in L. santoensis n. sp. Th e species clearly diff ers from L. santoensis n. sp. by female copulatory papilla only.

DESCRIPTION
Species of small size, dark brown general colouration. Dark ring on cerci apex present. Hind tibiae dorsal face with 5 inner and 7 outer spines above spurs, and 3 inner and 5 outer spines between spurs.

Male
Unknown.

Female
FWs short (Fig. 11C), reaching beyond posterior margin of fi rst tergite, separated by a distance equal to length; dorsal fi eld with 3 strong whitish and 2 fainter longitudinal veins. Lateral fi eld darker than dorsal fi eld, with 3 strong dark brown longitudinal veins including MA and R. Ovipositor short but slightly longer than average L. santoensis n. sp.; apex lanceolate, slightly denticulate on dorsal edge (Fig. 6I). Female genitalia: copulatory papilla fl at (Fig. 12G, H), sclerotized on both basal and apical apex, deeply curved, the ventral side concave, with a ventral bump.

Measurements
See Table 14.
HABITAT, LIFE HISTORY TRAITS AND BEHAVIOUR Not documented.

AND HABITATS
According to the detailed information obtained in Espiritu Santo, the crickets of the subfamily Eneopterinae are very abundant in Vanuatu, both in primary forests and secondary habitats (gardens, cultures, edges, costal areas). Two related genera belonging to the tribe Lebinthini are represented by several species (three Cardiodactylus, two Lebinthus) with the following pattern of distribution.
In every studied locality, a couple of Cardiodactylus sympatric species belonging to both species groups is present. Th e species C. enkraussi (Efordi group) is found everywhere on the island, together with a species of the Novaeguineae group: C. novaeguineae near coastal areas (Luganville, Peavot, Penaoru, Vatthé, etc.), and C. tankara n. sp. in inland areas (Butmas). Th ese two species are similar in terms of detailed  (Tables 1; 2): C. enkraussi (Efordi group) is present in relatively dense populations, deep within vegetation, and its song is little conspicuous, with limited intensity, while individuals of C. noveaguineae or C. tankara n. sp. (Novaeguineae group) are more spaced from one another and occupy more conspicuous and generally higher calling sites (large leaves of bushes, ferns or trees), and they also sing more loudly compared to C. enkraussi. Th e situation is diff erent in Lebinthus. Lebinthus santoensis n. sp., found in Espiritu Santo but also in Pentecost Is., is very similar to L. lifouensis (New Caledonia, Lifou Is.) and L. malekulensis n. sp. (Vanuatu, Malekula Is.). It is widespread in Espiritu Santo and has been found at every studied location, except in Butmas area, which is far from coastal areas and river banks.
According to homogeneous morphology, including male genitalia, FW venation, and calling song, the Lebinthus species from Vanuatu and the Loyalty Islands may belong to the same species group. Within this group, however, L. nattawa n. sp., endemic to Espiritu Santo, seems more diff erent from L. santoensis n. sp. than the later is from L. lifou ensis. Th e two species are found in nearby areas in Nattawa, but L. santoensis n. sp. in open clearings and edge forested areas and L. nattawa n. sp. in forested areas. Th is suggests several successive colonization events, possibly related to behavioural and/or adaptive differentiation, which will be analyzed in upcoming molecular studies.
Further investigations in other islands of Vanuatu will be needed to draw clear conclusions about the pattern and history of colonisation of Eneopterinae in the archipelago. Despite the weak amount of data available so far, the information found on collection material and previous studies (Table 15) shows that the same general pattern may be found in several, if not most, other islands, with more or less complexity depending on the size of the islands. For instance, the islands Malekula and Pentecost show one species of each Cardiodactylus group and one Lebinthus species, while the islands Aoba, Efate, Epi and Tanna show a couple of Cardiodactylus species from the Novaeguineae group, which could be the equivalent of C. novaeguineae and C. tankara n. sp. in Espiritu Santo.

DIVERSITY OF ACOUSTIC TRAITS
Th e eneopterine species found in Espiritu Santo contribute to the knowledge and documentation of the diversity of the subfamily in terms of acoustic signals and reproductive behaviours.
Th e new data confi rm the main spectral properties of the Lebinthini tribe, i.e. the use of high dominant frequencies (Robillard & Desutter-Grandcolas 2004b) and the use of harmonics as dominant frequency instead of the fundamental frequency (Robillard et al. 2007). All Cardiodactylus and Lebinthus species presented here are conforming to the expectations in terms of frequency spectra, as their songs are consistent with species previously documented for both genera (Robillard et al. 2007). However the new species L. santoensis n. sp. adds to the diversity of Eneopterinae, and of crickets in general, by having a dominant frequency of 26.5 kHz, thus reaching beyond the human audible frequency limit of about 20 kHz. Although ultrasonic frequencies are usual in tettigonids (e.g., Morris et al. 1989;Montealegre-Z & Morris 1999;Naskrecki 2000;Montealegre-Z et al. 2006), they had never been documented before in crickets, and L. santoensis n. sp. is consequently the fi rst ultrasonic cricket. It clearly suggests that Eneopterinae crickets have evolved toward a new mode of acoustic communication using the ultrasonic frequency range for calling.
To a lesser extent, the diversity of the subfamily is also increased in terms of temporal patterns. For instance, Cardiodactylus species documented here clearly show several distinctive song rhythms (two-part echemes vs. single echemes), which are likely to be only a sample of the diversity existing throughout the genus, as suggested by the songs of C. novaeguineae and C. guttulus (Robillard & Ichikawa in press).