Leptophyes axeli Willemse, Odé & Tilmans, 2022

Willemse, Luc, Odé, Baudewijn & Tilmans, Jos, 2022, Leptophyes axeli sp. nov. a new bush-cricket from Crete, Greece (Orthoptera: Tettigoniidae: Phaneropterinae), Zootaxa 5125 (5), pp. 536-546 : 537-544

Leptophyes axeli Willemse, Odé & Tilmans sp. nov.

Figs 1–24

Material examined ( 5♂, 5♀). Holotype ♂ ( RMNH.5106294), 1♂ ( RMNH.5106263), 2♀ ( RMNH.5106264, RMNH.5106295) paratypes ( RMNH): Greece — Crete (Chania): Psariana-Aligi ; on Rubus next to road; 420m; 17.VI.2019 –loc4 leg. L.Willemse & J.Tilmans; N35.351833°; E23.694208° ( RMNH); allotype ♀ ( RMNH.5106283), 1♀ ( RMNH.5106284) paratype ( RMNH), 2♂ (2019.025.01, 2019.025.02), 1♀ (2019.025.03) paratypes ( CT): Greece — Crete (Chania): 0.4 km NE Vamvakades; open oak forest; 750m; 17.VI.2019 –loc 6 leg. L.Willemse & J.Tilmans; N 35.316483°; E 23.756119° ( RMNH); Greece — Crete (Chania): 0.5 km W of Kamaria; on Rubus and herbs; 345m; 18.VI.2019 –loc 2 leg. L.Willemse & J.Tilmans; N 35.282516°; E 23.778568° 1♂ ( RMNH.5106293) paratype ( RMNH).

(Primary) Sound recordings in sound library B. Odé: Holotype ( RMNH5106294 ): GR19 Olympus: 1098, 1107, 1108; paratype ( RMNH5106293 ): GR19 Olympus: 1100, 1109.

Description. Male (figs 1, 3–4) as type species, L. punctatissima , integument somewhat shiny.

Head broad; eyes prominent; fastigium (fig. 7) short, narrow, blunt not protruding anteriorly beyond the antennal sockets, one third to half as wide as scapus, sulcate; third antennal segment nearly as wide as the distance between antennal sockets, slightly wider than fastigium.

Pronotum (figs 8, 11) short, weakly saddle shaped, not protruding posteriorly beyond the mesonotum, equally widened in prozona and metazoan; anterior margin very weakly concave, posterior margin straight to weakly convex, in lateral view toward front and back gradually raised; sulcus between halfway and two thirds of its length; lateral lobe slightly wider than deep, lower margin short, covering epimeron, anteriorly sinuate, anterior corner hollow, in dorsal view clearly protruding, fore margin in lateral view slight convex, hind margin straight, in posterior view weakly convex; prothoracic spiracle large.

Fore wings (figs 8, 11) not covered by pronotum except base laterally, about 1.5 times longer than pronotum, apical margin reaching hind margin of second tergite, with veins, archedictyon and bulging of distal end of Cu2 on hind margin rather pronounced (fig. 9), at rest distal part of fore margin convex to truncate; stridulatory file (fig. 13) file weakly arcuate, not reaching hind margin of fore wing, in profile weakly depressed in the middle, with 84–89 teeth, spacing hardly decreasing from the proximal tip to the distal tip, in proximal half hardly widening, almost equally broad, narrowing in the distal half; shortest distance between proximal and distal most tooth 1.25–1.64 mm.

Legs with hind femur 5.6–7.2 times longer than pronotum; outer and inner ventral margin hind femur with 2–6 and 1–3 spines respectively (fig. 12), fore and mid femur spineless.

Abdomen with second tergite bristle-like hairy mediodorsally, remaining tergites hairless; 10 th tergite medially produced backwards into trapezoid protuberance (fig. 10), depressed in the center, hind margin swollen, straight, covering the epiproct, weakly downcurved; cerci (fig. 14–15,17), strongly narrowed from the base, conical and straight in basal third, conical, somewhat flattened and strongly curved inward in upper two thirds, the apical third spiral-like turned downward, terminating in stout and sharp apical denticle; subgenital plate (fig. 16, 18) in ventral view oval, widening from base, halfway widest, in apical half narrowing, folded and strongly upcurved, chute formed, reaching up to the epiproct, margins swollen, posterior margin straight between the slightly protruding tips formed by the side margins.

Coloration (fig. 1) General color green to pale green, abdomen and less so thorax finely rusty brown spotted.

Head with frons, clypeus and labrum yellowish to creamy white, genae yellowish to green; vertex and first two antennal segments rusty brown with a narrow median and a wider postocular yellow or creamy white stripe often bordered with black markings. Flagellum of antennae from blackish to pale brown, sparsely annulated with yellow. Pronotum with dorsum rusty brown with or without pale central line, lighter in mesozona, darker brown along fore margin bordered on the sides by yellow or creamy white lateral band; lateral lobe green or pale yellowish green. Fore wings with stridulatory apparatus rusty brown, stridulatory vein yellowish white, with a black lateral streak along longitudinal folding of the wing widening apically, downfolded anterior areas and in some specimen’s apex of elytron greenish to yellowish white. Legs of general color, lower outer and inner keel of fore and mid femora blackish, upper side of fore and mid femora and fore and mid tibiae usually with blackish streaks. Abdomen green with a wide rusty brown median band and with or without a distinct white band along the side, last tergite with hind margin toward the middle more or less distinctly blackish, protuberance epiproct and cerci chestnut brown; subgenital plate pale yellowish, darkening somewhat apically; sternite green, with central white square.

Bioacoustics. The song of L. axeli sp. nov. consists of a repetition of very short syllables (fig 19). Syllables last 50–70ms and are repeated at a rate of about 1/s at maximum, but frequently at a lower rate. In our sound recordings frequently only short series of about 4–10 syllables are produced, followed by longer intervals. Each syllable consists of 27–40 impulses that show a marked crescendo, with the first impulses weak and the loudest impulses in the second half of the syllable. The final few impulses are weaker again. The frequency spectrum of the song shows frequencies between 15kHz and 90kHz, with a peak between 30–40kHz.

Female (figs 2, 5–6): as male. Pronotum (figs 20–21) only raised toward the back. Fore wings (figs 20–21) short, broadly overlapping, reaching or surpassing posterior margin of the first tergite, 0.75–0.85 as long as pronotum. Legs with hind femur 5.9–6.4 times longer than pronotum, outer and inner ventral margin with 2–6 and 1–2 spines respectively. Basal fold of lower ovipositor valve (fig. 23) somewhat swollen, extending laterally with the gonangulum forming a large pit that opens anterolaterally. 10 th abdominal tergite (fig. 22) in the middle with bow-shaped extension, more or less folded downward. Cerci (fig. 22) conical, stout, 2.2 times longer than greatest width, apical third strongly narrowed, slightly bend inward, apex pointed. Ovipositor (fig. 23) slightly widening toward the middle, widest around the middle, margins subparallel in basal half, upper margin extremely weak concave, edge in apical half obtusely serrate, lower margin straight in basal half, convex in apical half edge finely dentate. Subgenital plate small, triangular, apex slightly pulled out, sides inflated.

Coloration (fig. 2) as in male, less pronounced; ovipositor green.

Measurements (length in mm) and ratios. Body ♂ 11.4–13.9, ♀ 11.7–12.9; pronotum ♂ 2.3–2.6, ♀ 2.6–2.8; elytron ♂ 3.0–3.6, ♀ 2.0–2.3; hind femur ♂ 13.4–15.5, ♀ 16.1–17.9; ovipositor 8.0–8.6. Ratio fore tibia/pronotum ♂ 2.9–3.5, ♀ 2.8–3.2, hind femur/pronotum ♂ 5.6–7.2, ♀ 5.9–6.4, ovipositor/pronotum 2.9–3.2 and hind femur/ ovipositor 1.9–2.1.

Generic assignment. L. axeli sp. nov. has been assigned to Leptophyes based on the following characteristics: fore tibiae in the male and female respectively 2.9–3.5 and 2.8–3.2 times longer than the pronotum, anterior margin of the lateral lobe of the pronotum vertical, not protruding, the flat ovipositor slightly widening from the base with finely serrated apex and the male cercus lacking a basal tubercle. L. axeli shares the distinct median protuberance on the last abdominal tergite with Andreiniimon . In L. axe li the protuberance is much smaller than in Andreiniimon , the female subgenital plate is triangular and not transverse as in Andreiniimon and the high peak frequency in the male calling song in L. axeli is lower (30–40kHz) than in Andreiniimon (60kHz).

Differential diagnosis. Within Leptophyes , male L. axeli sp. nov. is clearly differentiated from all other species by the supra-anal plate being extended into a protuberance, somewhat reminiscent of Andreiniimon nuptialis and by the slender, strongly inward and slightly spirally down curved cerci in the male. With the third antennal segment being relatively narrow, the short pronotum with vertical side flaps, the fore wings not covered by the pronotum and the ovipositor from the base slightly widening distally, L. axeli sp. nov. belongs to the ‘punctatissima’ group of species in Leptophyes sensu Bey-Bienko (1954) . From species of the ‘punctatissima’ group occurring in Turkey and the Middle-East ( L. festae , L. karanae , L. peneri , L. helleri ) male L. axeli sp. nov. differ by the tip of the male cercus not being spine-like but simply pointed. Male L. nigrovittata , a species from the ‘puntatissima’ group found in the Caucasus, is characterised by a slender, almost straight cercus, the tip being blunt with a small inward pointing denticle, resembling cerci found in species of the ‘Iranica’ Group and very different from the cercus in L. axeli sp. nov. From the European species of the ‘punctatissima’ group, male L. axeli sp. nov. differ from L. laticauda and L. intermedia in the cercus not being slender but rather compact, the tip not being pointed but blunt with a small denticle or tooth and in the ventral side of the hind femur lacking spinules. Overall L. axeli sp. nov. most closely resembles L. punctatissima , L. asamo , L. calabra , L. sicula and L. lisae , but differs from these species except for the cercus and the protuberance on the anal tergite also in the relatively long wings. L. axeli shares with L. sicula and L. lisae the cerci being bent from halfway up whereas in L. punctatissima and L. asamo the cercus is bent more apically.

Within the ‘punctatissima’ group of species in Leptophyes females are less easy to distinguish. Female L. axeli sp. nov. differ from L. calabra , L. intermedia and L. sicula in the distinctly larger length of the visible part of the fore wings and length of ovipositor compared to the pronotum. In L. axeli sp. nov. the inner and outer keel on the ventral side of the hind femur carry spines whereas in L. laticauda they are bare. Differences with other species in the ‘punctatissima’ group are less distinct. The very large lateral pit of the ovipositor in L. axeli sp. nov. combined with its relatively long ovipositor and visible part of the fore wing can be used to quite clearly differentiate it from for instance L. punctatissima , but less so from other species

Based on material at hand and taxonomic treatments provided in published papers, male and female character states, useful to differentiate species within Leptophyes , are summarized in Table 1 . An illustrated key to the European species of Leptophyes is provided by Kleukers et al. (2010).

0. species group sensu Bey-Benko (1954): A: albovittata; I: iranica; P: punctatissima

1. male cercus shape a. 1. constricted; 2. not constricted

b. 1. (nearly) straight; 2. bent halfway; 3. bent at 2/3 of the length

2. male cercus tip a. 1. tapering; 2. blunt

b. 1. short tooth/denticle; 2. long tooth

3. number of stridulatory teeth

4. stridulatory file: 1. largely equally broad; 2. widest in middle part; 3. widest in proximal 2/3

5. male ratio length visible tegmen/pronotum: 1: <0.6; 2: 0.6–0.9; 3. 0.9–1.2; 4.> 1.3

6. male bulge elytron: 1. weak; 2. strong

7. hind margin last tergite male: 1. straight to weak convex; 2. extended

8. hind femur ventrally: 1. with spinules; 2. bare

9. female ratio length visible tegmen/pronotum: 1. <0.3; 2. 0.4–0.6; 3.> 0.7

10. female ratio length ovipositor/pronotum: 1. <2.0; 2. 2.0–2.6; 3.> 2.7

The song of L. axeli sp. nov. has been compared with the other European and Turkish species of the genus Leptophyes and also with Andreiniimon nuptialis . We combined both data from personal sound recordings, published data ( Ragge & Reynolds 1998; Heller 1988) and published sound recordings (Systax, Cigliano et al. 2021, Sardet et al. 2021, Sevgili 2004, Ingrisch & Pavicevic 2010) to summarize the song characters in Table 2 .

The song of L. axeli sp. nov. proves to be highly characteristic in the high number of impulses showing a crescendo within the unparted syllable. The species in this respect clearly differs from the other European and known Turkish species of Leptophyes . Also, the lower maximum of the frequency spectrum presents a clear difference with Andreiniimon . Moreover, all the species of Leptophyes with the exception of L. albovittata show a maximum frequency between 20 and 50kHz, whereas Andreiniimon shows a maximum at 60kHz.

The female response song has not yet been recorded but may be present in L. axeli sp.n. as it is known for many of the other species of Leptophyes ( Heller et al. 2018) .

Habitat. The species occupies shadowy spaces in open forests with a luxurious undergrowth of ferns, blackberries ( Rubus ) and roses ( Rosa ). This habitat is typical for the area West of the Lefka range which consists of a myriad of hilly ridges running mostly north to south, reaching up to 500–1000m, covered by maquis and smaller and larger patches of open forest especially along the lower parts of the valleys. Similar rugged landscapes with patches of open forest extend further to the north and east along the northern foothills of the Lefka range. The region where this kind of habitat is found is sparsely populated and agricultural activities are predominantly restricted to the valleys, in some places hill slopes being transformed to olive orchards.

Distribution. The three locations where the species has been found (fig. 24) are situated in the southwestern quadrant of Chania in western Crete which is an area in Crete with a relatively high annual rainfall ( Varouchakis et al. 2018).

Etymology. The species is named in honour of Axel Hochkirch in recognition of his unwavering efforts and contributions in the field of Orthoptera research in general and Orthoptera conservation in particular. He adds to these disciplines by a wide variety of activities including his own research, supervising MSc and PhD students and chairing the IUCN Grasshopper Specialist Group.

Figures

FIGURES 1–2. Leptophyes axeli sp. nov., 1. male reared from nymph. Psariana, paratype (RMNH5106263), 2. Female reared from nymph. Vamvakades, allotype (RMNH5106283). Photos R. Kleukers

FIGURES 3–6. Leptophyes axeli sp. nov. habitus, 3. male holotype dorsal, 4. lateral; 5. female allotype dorsal, 6. lateral.

FIGURES 7–13. Leptophyes axeli sp. nov. male, 7. head dorsal, 8. pronotum and elytron, lateral, 9. left elytron, ventral, 10. anal tergite, dorsal, 11. pronotum and elytron, dorsal, 12. ventral side hind femur, ventro-lateral, 13. stridulatory file. Bar: 1 mm.

FIGURES 14–18. Leptophyes axeli sp. nov. male, 14. cercus dorsal, 15. cercus lateral, 16. subgenital plate ventral, 17. cercus caudal, 18. subgenital plate lateral. Bar: 1 mm.

FIGURE 19. Leptophyes axeli sp. nov. Bioacoustics: A. Oscillogram (10s) of calling song; B. Oscillogram (200ms) of one syllable of Holotype (RMNH5106294); C. Oscillogram (200ms) of one syllable of paratype (RMNH5106293): D. Frequency spectrum of the song.

FIGURES 20–23. Leptophyes axeli sp. nov. female, 20. pronotum and elytron, dorsal, 21. pronotum and elytron, lateral, 22. anal tergite and cerci, dorsal, 23. ovipositor, lateral. Bar: 1 mm.

FIGURE 24. Distribution Leptophyes axeli sp. nov.