Nisitrus Saussure, 1878

Tan, Ming Kai, Wahab, Rodzay bin Haji Abdul, Japir, Razy, Chung, Authur Y. C. & Robillard, Tony, 2021, Revision of the cricket genus Nisitrus Saussure (Orthoptera: Gryllidae: Eneopterinae) and descriptions of five new species, European Journal of Taxonomy 761 (1), pp. 1-75: 12-25

publication ID

https://doi.org/10.5852/ejt.2021.761.1449

publication LSID

lsid:zoobank.org:pub:519E2F56-40E1-4431-BC90-8484E308D16E

DOI

http://doi.org/10.5281/zenodo.5169988

persistent identifier

http://treatment.plazi.org/id/039487A4-FFE7-FFE4-FD84-F13EFAA2FDE3

treatment provided by

Felipe

scientific name

Nisitrus Saussure, 1878
status

 

Genus Nisitrus Saussure, 1878  

Nisitra Walker, 1869: 91   .

Nisitra   – Chopard 1940: 199.

Nisitrus   – Saussure 1878: 511, 522 (nomen novum for Nisitra Walker   ). — Chopard 1968: 352. — Desutter-Grandcolas 1990: 239. — Otte 1994: 67. — Preston-Mafham 2000: 2241 (behaviour). — Robillard & Desutter-Grandcolas 2004a: 276; 2004b: 578; 2004c: 304; 2006: 644; 2008: 67 ( Nisitrini   tribe); 2011: 637. — Robillard et al. 2007: 1265. — Desutter-Grandcolas et al. 2010: 616. — Nattier et al. 2011: 2201 (phylogeny and molecular dating). — Robillard & Tan 2013: 707 View Cited Treatment (redescription and diagnosis). — Vicente et al. 2017: 2203 (phylogeny, historical biogeography). — Cigliano et al. 2020 ( Orthoptera   Species File Online).

Type species

Nisitra vittatus ( Haan, 1844)   .

Remarks on type species

Kirby (1906) and Chopard (1968) listed N. vittata   as the type species of Nisitra   and treated the original type species N. marginata Walker, 1869   as a synonym of N. vittata   . Subsequent authors listed N. vittatus   as the type species of the replacement name Nisitrus   , although Otte (1994) reinstated N. marginatus   as a valid species (Braun 2013 in Cigliano et al. 2020). The present revision revalidates the synonymy of N. marginatus   under N. vittatus   , making N. vittatus   the valid type species of the genus.

Diagnosis (emended from Robillard & Tan 2013)

Among genera of Eneopterinae   , Nisitrus   is characterised by an elegant, wasp-like, slender and colourful body ( Figs 7–9 View Fig View Fig View Fig ). Size average for subfamily. Colouration vivid, dominantly yellow, whitish and black, with species-specific patterns, particularly in the head ( Figs 10–11 View Fig View Fig ), pronotum ( Figs 11–12 View Fig View Fig ) and FWs ( Figs 12–14 View Fig View Fig View Fig ). Characteristic head shape with narrow fastigium and large prominent eyes with thin dorso-ventral black stripes. Pronotum setose, square-shaped to slightly trapezoidal, usually bisinuated posteriorly. Metanotum with large glandular structures in males, made of a wide pit on scutum and a pair of posterior pits on scutellum, with glandular pores mostly organised by groups of 2 or 3 ( Fig. 15 View Fig ). FWs more or less as long as abdomen. Male Nisitrus   show modified FW venation and characteristic glossy transparency. Hindwings longer than FWs, bicoloured in most species, their base transparent with a wide dark posterior margin. Legs long and thin, FIII with a characteristic narrowed area before knee. Other general traits: TI with two tympana, inner one slit-like, covered by a swollen cuticular expansion; outer tympanum oval, its membrane transversally plicate in dorsal half. TI with three apical spurs; outer dorsal spur missing. TII with four apical spurs, inner longest. TIII with three inner and three outer apical spurs, median longest on each side; four pairs of subapical spurs, inner and outer spurs almost straight, their apex hook-like; TIII serrulate over whole length, slightly furrowed dorsally. Tarsomeres III-1 with one row of dorsal spines on external edge in addition to apical spines. Apical claws of legs slightly indented. Both males and females show characteristic genitalia.

Male genitalia ( Fig. 16 View Fig ) with membranous and setose lophi well individualised; pseudepiphallic parameres including two membranous posterior lobes and a sclerotized anterior lobe oriented anteriorly toward median axis of genitalia and carrying a secondary preapical sclerotized lobe; ectophallic arc transverse, incomplete due to a little-sclerotized median area; ectophallic fold narrowed preapically, its apex narrow, located between anterior apex of pseudepiphallic parameres; dorsal part of fold sclerotized, forming two elongated sclerites connected to the median area of arc; ventral part of ectophallic fold membranous, with two strong rounded lateral sclerites of variable shapes. Membrane of endophallic cavity smooth. Female copulatory papilla ( Fig. 17 View Fig ) conical, apex generally sclerotized and pointed. Ovipositor typically longer than FIII; apex thin with both dorsal and ventral edges smooth.

Phylogenetic relationships

Based on previous phylogenetic studies ( Robillard & Desutter-Grandcolas 2004c; Nattier et al. 2011; Vicente et al. 2017), Nisitrus   is the sister genus of Paranisitra Chopard, 1925   (revision in Gorochov 2009 and Baroga-Barbecho et al. 2019). The two genera form the Nisitrini   tribe ( Robillard & Desutter-Grandcolas 2008) and are very close morphologically; Paranisitra   is mostly characterised by a lack of wings in both sexes, but except for this, it shares with Nisitrus   its general body shape, long thin legs with indented claws, colouration with yellow and black, head shape with large prominent eyes and narrow fastigium, and the general structure of male and female genitalia. Nisitrini   are less easy to relate to other clades of Eneopterinae   .

Natural history

Species tend to be found at forest edges and gaps in the forest where the vegetation is more exposed. They are also found among shrubs and herbaceous plants (but not grasses). Nisitrus   are observed to be generally diurnal, during which the males can be heard calling and individuals are found foraging in the vegetation. It seems as Nisitrus   are mostly herbivorous, feeding on leaves, but also on flowers ( Tan et al. 2017). Nisitrus   are also observed to congregate with one another on the same plant, sometimes making up of more than 20 individuals of both adults and nymphs. They can be considered a pest in some parts of Southeast Asia ( Willemse 2001).

Included species

Nisitrus brunnerianus   from Borneo and Java; N. crucius   sp. nov. and N. danum   sp. nov. (both from Borneo); N. hughtani   sp. nov. from Sumatra; N. hyalinus   from Borneo; N. insignis   from Sumatra and Malay Peninsula; N. malaya   sp. nov. from Malay Peninsula; N. musicus   and N. rindu   sp. nov. from Borneo; and N. vittatus   from Sumatra and Borneo.

Distribution

Borneo (Sabah and Sarawak States of East Malaysia, Brunei Darussalam, and Kalimantan State of Indonesia), Java, Malay Peninsula (Peninsular Malaysia and Singapore) and Sumatra ( Indonesia) ( Fig. 5 View Fig ).

Key to the species of Nisitrus Saussure, 1878  

1. Frons mostly black, or with large dark markings (e.g., cross-shaped pattern); gena usually black, although may have yellow band ventral of eye ................................................................................ 2

– Frons mostly yellow, sometimes with small dots but without large dark markings; gena usually yellow ............................................................................................................................................... 5

2. FW with longitudinal white stripe around region of CuA, M and R with a distinct margin from black colouration on dorsal field; lateral field usually infumated black ventrally. Distribution: Sumatra ................................................................................... N. hughtani Robillard & Tan   sp. nov.

– FW with longitudinal white stripe around region of CuA, M and R darkens progressively towards the dorsal field without a distinct margin from black colouration on dorsal field; lateral field usually light coloured or transparent ventrally. Distribution: Borneo and Java ............................................ 3

3. Smaller in size, female FWL typically <11.3 mm. Frons with a characteristic black cross marking .................................................................................................... N. crucius Robillard & Tan   sp. nov.

– Larger in size, female FWL typically> 11.8 mm. Frons completely black; without a characteristic black cross marking .......................................................................................................................... 4

4. Dorsum of head completely black. Pronotal lateral lobe either with ventral half yellow or with an oval yellow spot at the anterior end ................................................ N. brunnerianus Saussure, 1878  

– Dorsum of head pale with some dark markings. Pronotal lateral lobe with a characteristic dorsal yellow band that extends ventrally ............................................... N. rindu Robillard & Tan   sp. nov.

5. Frons with black band between eyes, mouthparts mostly yellow. Body darker; female FW typically with infumated black cells, with lateral parts of dorsal field usually with an infumated yellow longitudinal stripe. Distribution: Borneo (Sabah) ...................... N. danum Robillard & Tan   sp. nov.

– Frons without black band between eyes, mouthparts black. Body usually with more yellow colouration; male FW with some black and white infumation, but generally transparent. Distribution: Borneo, Malay Peninsula and Sumatra .......................................................................................................... 6

6. Legs usually pale in colouration; FIII with at least one black longitudinal stripe on external face. Male FW with distinct infumated white spots and infumated black pattern near base, sometimes with infumated white patterns around chords, but otherwise transparent, harp very small, with one distinct straight oblique vein; female FW almost always with yellow/white veins. Distribution: Sumatra .................................................................................................... N. insignis Saussure, 1878  

– Legs usually brown in colouration; FIII with faint or without black longitudinal stripe on external face. Male FW with infumated black pattern near base, sometimes with infumated white spots, but otherwise transparent, harp larger, with 3 oblique veins; female FW sometimes with yellow/white veins. Distribution: Sumatra, Borneo, Malay Peninsula ................................................................... 7

7. Eyes dark when alive. Frons yellow, face part of fastigium (including scapes) and mouthparts black, maxillary palpi yellow; dorsal part of legs black. Male pseudepiphallus slender. Distribution: Borneo, near Kinabalu area .................................................................................... N. musicus Ingrisch, 1987  

– Eyes green when alive. Frons yellow to brown, mouthparts sometimes yellow or brown; legs typically homogenous brown. Pseudepiphallus more robust, broad. Distribution: Sumatra, Borneo, Malay Peninsula ........................................................................................................................................... 8

8. Lighter in colouration. Lateral field of FWs usually light in colouration. Juveniles of pale white colouration with numerous dark stripes all around the body. Female copulatory papilla without truncated lobule at the ventro-anterior end. Distribution: Borneo, Sumatra ...................................... ...................................................................................................................... N. vittatus ( Haan, 1844)  

– Darker in colouration. Lateral field of FWs usually dark in colouration. Juveniles of darker colouration, usually grey, their pronotum without longitudinal stripes but dorsal disk sometimes with a large velvety black spot. Female copulatory papilla with a truncated lobule at the ventro-anterior end. Distribution: Malay Peninsula ................................................... N. malaya Robillard & Tan   sp. nov.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Orthoptera

Family

Gryllidae

Loc

Nisitrus Saussure, 1878

Tan, Ming Kai, Wahab, Rodzay bin Haji Abdul, Japir, Razy, Chung, Authur Y. C. & Robillard, Tony 2021
2021
Loc

Nisitra

Chopard L. 1940: 199
1940
Loc

Nisitrus

Vicente N. & Kergoat G. J. & Dong J. & Yotoko K. & Legendre F. & Nattier R. & Robillard T. 2017: 2203
Robillard T. & Tan M. K. 2013: 707
Nattier R. & Robillard T. & Desutter-Grandcolas L. & Couloux A. & Grandcolas P. 2011: 2201
Desutter-Grandcolas L. & Blanchet E. & Robillard T. & Magal C. & Vannier F. & Dangles O. 2010: 616
Robillard R. & Desutter-Grandcolas L. 2008: 67
Robillard R. & Grandcolas P. & Desutter-Grandcolas L. 2007: 1265
Robillard T. & Desutter-Grandcolas L. 2006: 644
Robillard R. & Desutter-Grandcolas L. 2004: 276
Robillard R. & Desutter-Grandcolas L. 2004: 578
Robillard R. & Desutter-Grandcolas L. 2004: 304
Preston-Mafham K. 2000: 2241
Otte D. 1994: 67
Desutter-Grandcolas L. 1990: 239
Chopard L. 1968: 352
Saussure H. 1878: 511
1878
Loc

Nisitra

Walker F. 1869: 91
1869