Lebinthus luae Robillard & Tan, 2013

Robillard, Tony & Tan, Ming Kai, 2013, A Taxonomic Review Of Common But Little Known Crickets From Singapore And The Philippines (Insecta: Orthoptera: Eneopterinae), Raffles Bulletin of Zoology 61 (2), pp. 705-725 : 718-723

Lebinthus luae Robillard & Tan , new species

( Figs. 11E–H , 12D–F , 13C, D , 14D–F , 15D, E , 17 )

Lebinthus bitaeniatus Stål, 1877 – Robillard & Desutter-Grandcolas, 2004a: 275; 2006: 644; Robillard, 2011: 25

Lebinthus sp. – Tan, 2010: 246; Tan et al., 2012: 66; Tan, 2012: 4; Tan & Wang, 2012: 315

Lebinthus n. sp. affinis bitaeniatus – Robillard et al., 2013: 2003 > mechanism of stridulation

Material examined. — Holotype (male): Singapore: male(TR6), day, leaf litter ( ZRC), Labrador park, forêt secondaire littorale [coastal secondary forest], 01°15'59"N, 103°48'8.1"E, 57 m ( GPS Lab1), coll. T. Robillard, 12 Jun.2011 . Allotype (female): Singapore: female (TR42bis), day, leaf litter ( ZRC), Pulau Ubin Island , Jalan Endut Senin, 01°24'19.3"N, 103°57'58.7"E, 0 m, coll. T. Robillard, 30 Jun.2009 .

Paratypes (14 males, 7 females): Singapore : 1 male (TR4), call recording ( MNHN-ENSIF3207 ), same information as HT . 1 male (TR17) ( ZRC) ; 1 male (TR41) ( UPLB MNH) ; 1 male (TR16), 1 female (TR53) ( MNHN-ENSIF3206 ), same information as AT . 2 males (TR10, 11), leaf litter, call recording ( MNHN- ENSIF3107-3209 ) ; 1 male (TR9) copulation recording in the field ( MNHN-ENSIF3210 ), Labrador park, coastal secondary forest, 01°15'58.7"N, 103°48'10.3"E, 46 m ( GPS Lab 3), day, coll. T. Robillard, 14 Jun.2011 . 2 males (TR38, 54), day, leaf litter, enregistrement appel ( MNHN-ENSIF2740-3208 ), Labrador park, 01°16'02.2"N, 103°48'05.6"E, 46 m, coll. T. Robillard, 7 Jul.2009 . 2 females, day, leaf litter (dead in captivity) ( ZRC), 1 female, day, leaf litter (dead in captivity) ( UPLB MNH), Sentosa Island , 01°14'49.4"N, 103°50'01.1"E, 17 m, coll. T. Robillard, 6 Jul.2009 . 1 female ( MNHN-ENSIF3205 ), Semakan landfill, coll. RMBR Nature guide, 5 Dec.2009 . 1 male ( ZRC), Pulau Tekong , 7 Apr.1984, coll. D. H. Murphy ; 1 male ( ZRC), Sentosa , 20 Jan.1985, coll. D. H. Murphy ; 1 male, 1 female ( ZRC), Pulau Ubin , along Sensory Trail, 4 Dec.2009, coll. M. K. Tan ; 1 male, 1 female ( ZRC), Hindhede Nature Park , secondary forest, 2 Jun.2011, coll. M. K. Tan ; 1 male (TR23), night ( MNHN-ENSIF3090 ), Bukit Timah Nature Reserve , Hindhede trail, 01°15'57"N, 103°46'33.6"E, 68 m, 20 Jun.2011 , coll. T. Robillard .

Other material examined: Singapore: 1 male, 2 females ( MNHN), Labrador park, coastal secondary forest, reared specimens (generations F0–F1), 2011, coll. T. Robillard . 1 juvenile, leaf litter, (TR7) ( MNHN), Labrador park, coastal secondary forest, day, 01°15'57.8"N, 103°48'11.2"E, 42 m, 12 Jun.2011 , coll. T. Robillard . Indonesia: 3 females ( MNHN-ENSIF1432-1434 ), Doerian [Durian Island], Riouw-Arch [Riau Islands], Nov.1923, Coll. Dammerman ; 1 male, 2 females ( MNHN-ENSIF1431 , 1435 , 1436 ) , 1 female, identified L. bitaeniatus by T. Robillard (2004, in Robillard & Desutter-Grandcolas, 2004a), Doerian [ Durian Island ], Riouw-Arch [Riau Islands], Nov.1923, coll. Dammerman ; 1 female ( MZB. ORTH.10425), Java ( Lee ???), 22 Oct.1921, coll. L. Wachter. 2 females ( MZB. ORTH.9743-9744), Sumatra, Lampong , 4 Feb.1972, coll. Dulhoer ; 1 male ( MNHN) , 1 female ( MNHN-ENSIF1424 ) , 2 males, identified L. bitaeniatus by L. Chopard ( MZB. ORTH.10417, 10419), [Western Java], Tjibodas, 1400 m, No 259, Aug.1921 .

Diagnosis. — Species similar to L. bitaeniatus , but differs by general shape more stocky, darker colouration, wider yellowish or whitish longitudinal band along body, without a black line ventrally. Male genitalia wider and shorter than in L. bitaeniatus , differing by shape of pseudepiphallic parameres, ectophallic fold membranous (without strong M-shape sclerotisation).

Description. — Species of average size for the genus, of stocky shape. Colouration dark brown with wide yellow or whitish dorso-lateral longitudinal bands along the whole body ( Fig. 11 E–H ). Head dorsum with 6 wide dark brown longitudinal bands more or less distinct and sometimes fused together. Fastigium wider than long, setose, dark brown, apex yellow with two black spots on facial part. Scapes yellow and brown; antennae brown. Face variable, from yellow brown to darker brown. Epistomal suture yellow. Mouthparts yellow brown, including maxillary palpi. Lateral part of head with a yellow area posterior to eye, underlined by a large brownish area more or less homogeneous. Pronotum: Dorsal disk dark brown, its lateral edges yellow. Lateral lobes dark brown to orange brown, with little distinct lighter patterns near ventral margin, including the ventral corner and a brownish longitudinal line. Legs I and II light brown to yellow brown, femora with brown spots and longitudinal patterns, tibiae with rings. FIII brown, sometimes with dark spots and with striated dark patterns on outer faces; hind knees black; TIII black with yellow rings. For all pairs of legs, Ta1 and Ta3 yellow basally, dark brown apically. Abdomen homogeneously dark brown dorsally, covered with golden setae, lateral edges with yellow or whitish longitudinal bands. Sternites yellowish brown, with dark brown patterns laterally. Cerci yellowish basally, with black rings near apex, ventral side black.

Male: FWs not reaching abdomen mid-length ( Fig. 13C ). FW colouration: Cells and veins brown, not translucent; angle between dorsal and lateral fields whitish to yellow, forming a wide longitudinal band including CuA over its whole length, external margin of harp, MP, CuA/MP area, most MA/MP area, and small median fold; lateral field brown, without a black line underlying the yellow longitudinal band. FW venation ( Fig. 13C ): 1A angle wide (>100°); stridulatory file with 117–133 teeth (m = 126, n = 4), located on transverse and longitudinal parts of 1A. CuP absent. Area posterior to plectrum strongly sclerotised. Harp wide, with a longitudinal fold near angle of 1A (claval fold?); with 1 harp vein, strong and sometimes bifurcated at distal end. Distal part of CuA straight. Mirror (d1) not differentiated, resembling the other few cells of D alignment. Apical field absent, with no bifurcation of CuA posterior to diagonal vein. Lateral field dark brown to brown, with 5 strong longitudinal veins including MA, R and 3 more ventral veins; latero-dorsal angle made by MP; R without strong bifurcating veins. Subgenital plate elongate, clog-shaped.

Male genitalia ( Fig. 14D–F ): Pseudepiphallic sclerite trapezoidal, shorter and wider than in L. bitaeniatus , convex dorsally, its apex slightly trilobate, including a short median expansion and 2 lophi barely individualised, slightly divergent and finely setose. Anterior margin bisinuated, with a median indentation. Rami as long as 2/3 pseudepiphallic sclerite, proportionally longer than in L. bitaeniatus . Pseudepiphallic parameres with a wide sclerotised basis, trilobate, including a postero-dorsal lobe and 2 ventral lobes, the anterior one rounded and curved anteriorly. Ectophallic arc complete and wide. Ectophallic fold triangular and membranous. Ectophallic apodemes rather wide, long and parallel, exceeding anterior margin of pseudepiphallus, their bases with a pair of ventral membranous expansions. Endophallic sclerite long, exceeding anterior margin of pseudepiphallus, convex dorsally, its posterior apex with a small median triangular expansion and with short thick lateral arms; endophallic apodeme made of a narrow median crest.

Female: FWs short ( Fig. 13D ), slightly longer than pronotum, slightly overlapping basally; dorsal field grey brown, with 6 (n = 3) strong orange brown to brown longitudinal veins, less straight than in L. bitaeniatus , sometimes bifurcated; with weak transverse veins. Lateral edge of dorsal field with a wide yellow area including a faint longitudinal vein; first (external) strong longitudinal vein yellow basally. Lateral field with 4–5 (n = 4) strong straight longitudinal veins.

Female genitalia: Ovipositor shorter than hind femora; apex lanceolate, denticulate on dorsal edge ( Fig.7C ). Copulatory papilla ( Fig. 7F ) conical, with a narrow basal sclerotised area on ventral face; apex rounded, sclerotised on dorsal face only.

Juvenile: Similar to adults in colouration, mostly dark brown.

Life history traits: L. luae is a diurnal species living in more or less forested secondary habitats. Males sing from low plants above the leaf litter from early morning to dusk. Mating couples are generally observed on plant leaves or on top of the litter ( Fig. 15D, E ).

Behaviour. Calling song ( Fig. 17 ): In the field (n = 4; t°C = 27–30°C) the calling song of L. luae n. sp. lasts for 3.3 ± 1.2 s (echeme period = 30.1 ± 16.5 s) and is made of very indented syllables (amplitude modulation resulting in pauses within the syllable). As in L. bitaeniatus , this call is organised in two parts, the initial one consisting of 11 ± 5 well-spaced syllables (longer duration = 28.1 ± 9.8 ms; longer period = 219.9 ± 127.7 ms), the second part being a short trill made of 24 ± 3 syllables set closer together (shorter duration = 13.3 ± 2.2 ms; shorter period = 21.6 ± 3.7 ms). Each syllable is made of discrete pulses, produced by regular plectrum pauses, which in turn are caused by a discontinuous closing phase. Such a pattern produces a broad band spectrum between 12 and 30 kHz, with main energy centred at nearly 16.7 ± 1.3 kHz, which corresponds to the first and only peak of the spectrum.

Measurements: See Table 4.

Etymology. — This species is dedicated to H. K. Lua (ZRC curator).

Figures

Fig. 11. Lebinthus bitaeniatus (A–D): A, B, male; C, D, female; A, C, dorsal view; B, D, lateral view. Lebinthus luae (E–H): E, F, male; G, H, female; E, G, dorsal view; F, H, lateral view. Scale bar = 1 mm.

Fig. 12. Head: A–C, Lebinthus bitaeniatus; D–F, Lebinthus luae. A, D, dorsal view; B, E, facial view; C, F, lateral view. Scale bar = 1 mm.

Fig. 13. Forewing venation in dorsal view: A, B, Lebinthus bitaeniatus; C, D, Lebinthus luae. A, C male; B, D, female. Scale bar = 1 mm.

Fig. 14. Male genitalia: A–C, Lebinthus bitaeniatus; D–F, Lebinthus luae. A, D, dorsal view; B, E, lateral view; C, F, ventral view. Scale bars = 1 mm.

Fig. 15. Lebinthus bitaeniatus (A–C), in Mount Makiling (Luzon, Philippines) on campus near UPLB MNH: A, female on plant at night; B, male courting a female during afternoon on leaf litter; C, view of secondary habitat. Lebinthus luae (D, E), in Labrador Park, Singapore: D, male and female mating on branch (h = 30 cm) in the afternoon; E, male and juvenile foraging on fallen fruit.

Fig. 17. Calling song of Lebinthus luae. Oscillogram of 3 echemes (A); oscillogram (B) and sonogram (C) of 1 echeme; oscillogram (D) and linear power spectrum (E) of 1 syllable in the starting part of the echeme.

Fig. 7. Female genitalia: A–C, apex of ovipositor; D–F, copulatory papilla. A, D, Nisitrus vittatus; B, E, Lebinthus bitaeniatus; C, F, Lebinthus luae. Scale bars = 1 mm.