Amblycorypha monticola Forrest & Holbrook, 2025

Forrest, Timothy G., Hamel, Jennifer A. & Holbrook, C. Tate, 2025, Calling songs and duets of two new species in the Amblycorypha rotundifolia complex (Tettigoniidae, Phaneropterinae), Journal of Orthoptera Research 34 (2), pp. 233-248 : 233-248

Amblycorypha monticola Forrest & Holbrook sp. nov.

Figs 2 , 7 , 6 , 8 , 9 , 10 , 11 , 14 , 15 ; Table 1

Material examined. —

Holotype: USA • ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 21 Aug. 2006; T. G. Forrest leg.; Auc-M 01-2006 ; DNA (MS-086); REC (NA); UNCA to be transferred to FSCA . Allotype: USA • ♀; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 21 Aug. 2006; T. G. Forrest leg.; Auc-F 01-2006 ; DNA (NA); REC (NA); UNCA to be transferred to FSCA . Paratypes: (61 ♂, 33 ♀) USA • 1 ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 6 Aug. 2002; T. G. Forrest leg.; UNCA to be transferred to FSCA • 2 ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 12 Aug. 2002; T. G. Forrest leg.; UNCA to be transferred to FSCA • 2 ♂; North Carolina, Graham Co., Nantahala Nat. For. ; 35.3878°N, 83.9112°W; 7 Sep. 2002; T. G. Forrest leg.; UNCA to be transferred to FSCA • 2 ♀, 1 ♂; North Carolina, Buncombe Co., Cane Gap ; 35.8099°N, 82.3480°W; 12 Aug. 2003; T. G. Forrest leg.; UNCA to be transferred to FSCA • 2 ♀; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 13 Aug. 2003; K. B. Rice leg.; UNCA to be transferred to FSCA • 1 ♀, 3 ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 16 Sep. 2003; T. G. Forrest leg.; UNCA to be transferred to FSCA • 7 ♀, 5 ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 22 Jul. 2004; T. G. Forrest and J. A. Hamel leg.; UNCA to be transferred to FSCA • 3 ♀, 9 ♂; North Carolina, Graham Co., Nantahala Nat. For. ; 35.3694°N, 83.9168°W; 12 Aug. 2004; T. G. Forrest and J. A. Hamel leg.; UNCA to be transferred to FSCA • 1 ♀, 6 ♂; North Carolina, Haywood Co., Purchase Knob ; 35.5862°N, 83.0737°W; 17 Aug. 2004; T. G. Forrest, J. A. Hamel and C. T. Holbrook leg.; UNCA to be transferred to FSCA • 1 ♀, 2 ♂; North Carolina, Haywood Co., Balsam Gap ; 35.4404°N, 83.0777°W; 22 Aug. 2004; T. G. Forrest, J. A. Hamel and C. T. Holbrook leg.; UNCA to be transferred to FSCA • 1 ♂; North Carolina, Haywood Co., Spot Knob ; 35.3250°N, 82.9638°W; 22 Aug. 2004; T. G. Forrest, J. A. Hamel and C. T. Holbrook leg.; UNCA to be transferred to FSCA • 3 ♀, 6 ♂; North Carolina, Haywood Co., Cold Springs Creek ; 35.7644°N, 82.9766°W; 2 Sep. 2004; T. G. Forrest, J. A. Hamel and C. T. Holbrook leg.; UNCA to be transferred to FSCA • 7 ♀, 5 ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 21 Aug. 2006; T. G. Forrest leg.; UNCA to be transferred to FSCA • 1 ♀, 3 ♂; North Carolina, Haywood Co., Purchase Knob ; 35.5862°N, 83.0737°W; 14 Sep. 2006; T. G. Forrest leg.; UNCA to be transferred to FSCA • 2 ♀; North Carolina, Graham Co., Nantahala Nat. For. ; 35.3596°N, 83.9149°W; 23 Sep. 2006; T. G. Forrest leg.; UNCA to be transferred to FSCA • 1 ♀, 3 ♂; North Carolina, Madison Co, Max Patch ; 35.7968°N, 82.9619°W; 10 Oct. 2006; T. G. Forrest leg.; UNCA to be transferred to FSCA • 6 ♀; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 5 Jul. 2007; K. A. M. Dagg leg.; UNCA to be transferred to FSCA • 9 ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 5 Jul. 2007; K. A. M. Dagg leg.; UNCA to be transferred to FSCA • 1 ♀, 6 ♂; North Carolina, Buncombe Co., Beetree Gap ; 35.7001°N, 82.3989°W; 26 Aug. 2012; T. G. Forrest and L. D. Block leg.; UNCA to be transferred to FSCA • 2 ♀, 1 ♂; North Carolina, Madison Co., Bluff Mountain ; 35.8514°N, 82.8947°W; 3 Jun. 2017; T. G. Forrest leg.; UNCA to be transferred to FSCA .

Size measurements (mm). —

Holotype: PrnL: 5.3, PrnW: 3.9, TegL: 24.7, TegW: 8.5, HwEx: 4.2, FemL: 23.2, TibL: 24.0 mm. Allotype: PrnL: 6.1, PrnW: 4.0, TegL: 23.8, TegW: 8.1, HwEx: 3.1, FemL: 23.1, TibL: 23.7, OviL: 9.8 (Fig. 2 ).

Etymology. —

This species is named for its ecology, which includes mostly high-elevation oak-hickory forests in the southern Blue Ridge Mountains. The specific epithet is derived from Latin monti-: mountain and - cola: dweller.

Common name. —

Montane Round-winged Katydid

Differential diagnosis. —

Morphologically, A. monticola is cryptic with A. alexanderi and A. rotundifolia , two species whose populations are typically found near those of A. monticola . A. monticola are most easily distinguished from all members of the rotundifolia complex by their unique calling song. Males produce syllables at faster rates, 45 / s at 25 ° C, than any other species in the complex. While calling, 4–7 syllables are grouped into rhythmic echemes, a structure not found in other species’ songs. Echemes are constantly produced at slow rates of 1.6 / s at 25 ° C. Males then transition to faster echemes reaching peak rates of 3.1 / s at 25 ° C followed by echemes separated by one or two ticks. Populations of A. monticola tend to be at elevations above ~ 1000 m, whereas other species in the complex are more likely to be found at lower elevations.

Description. —

Color is usually green. Lateral lobe of the pronotum with shallow humeral sinus and the metasternal lobes are transverse (see characteristics of the rotundifolia complex, Walker et al. 2003). Morphological measurements (x ̄ ± SE in mm, N) of females average PrnL: 6.0 ± 0.04, 34; PrnW: 4.1 ± 0.03, 34; TegL: 25.1 ± 0.18, 33; TegW: 8.2 ± 0.07, 34; FemL: 24.2 ± 0.18, 32; TibL: 24.9 ± 0.23, 32; OviL: 10.0 ± 0.08, 34. Male measurements averaged PrnL: 5.3 ± 0.03, 61; PrnW: 3.9 ± 0.02, 61; TegL: 25.2 ± 0.13, 61; TegW: 8.4 ± 0.08, 61; FemL: 23.0 ± 0.14, 57; TibL: 24.2 ± 0.18, 56 (Table 1 ).

Calling songs of A. monticola are emitted as regularly timed echemes consisting of 4–7 syllables. Echemes are constantly produced at ~ 1.6 / s at 25 ° C, which transitions to a faster series of echemes emitted at 3.1 / s at 25 ° C. In later portions of the fast series, ticks are emitted between the echemes. Within the echemes, the syllable rates are 45 / s at 25 ° C and are the same whether echemes are sung slow or fast.

Figures

Fig. 2. Holotype (A. Dorsal view, B. Lateral view) and allotype (C. Dorsal view, D. Lateral view) of Amblycorypha monticola, Montane Round-winged Katydid. Scale bars: 5 mm.

Fig. 6. Mean (± SE) syllable rates as a function of temperature during calling by male A. zipticka for clicks (blue fit: rate = 0.059 T- 0.010) and zips (red fit: rate = 0.150 T + 0.052). Numbers beside each mean represent the individual (n = 17) whose mean rate was measured. Individuals whose click rate and zip rate were calculated at the same temperature are from the same recording. The dotted line is the same function for clicks of A. alexanderi from Walker et al. 2003.

Fig. 7. Oscillograms showing the fine temporal structure of echemes produced by 4 male A. monticola. The smaller amplitude sounds between each impulse train are from the opening stroke of the tegmina. Opening (O) and closing (C) strokes are indicated for the top oscillogram. Scale bar: 100 ms.

Fig. 8. Oscillograms (25 s) of the calling songs of 4 male A. monticola showing the general temporal structure of calling. Songs are continuous slow echemes of 3–8 syllables that transition to short faster series of echemes that include ticks between them in later parts of the series. Multiple short series are often repeated for many seconds. Scale bar: 5 s.

Fig. 9. A, E. Oscillograms (20 s) of calling songs of 2 male A. monticola. Scale bar: 1 s. B, F. Oscillogram and spectrogram of echemes highlighted by blue in A and E, with 8 syllables (B) and 7 syllables (F) typically produced continuously at slow rates during calling. C, G. Oscillogram and spectrogram of echemes indicated by the red outline in A and E, respectively. D, H. Echemes highlighted in green with one or two ticks produced between echemes during faster portions of calling.

Fig. 10. Mean (± SE) syllable rates within echemes as a function of temperature for individuals from different populations of A. monticola in western North Carolina. Numbers beside each mean are the individual (n = 29) whose mean rate was measured. Individuals whose rates were calculated at the same temperature are syllable rates from the same recording but measured during slow (blue fit: rate = 2.41 T- 14.1) and fast (red fit: rate = 2.36 T- 14.2) portions of the song. Dotted line is the rate function for A. rotundifolia (Walker et al. 2003).

Fig. 11. Mean (± SE) echeme rate as a function of temperature for A. monticola males from different North Carolina populations. Numbers beside each mean are the individual (n = 29) whose mean rate was measured. Individuals whose rates were calculated at the same temperature are echeme rates from the same recording but measured during slow (blue fit: rate = 0.086 T- 0.526) and fast (red fit: rate = 0.157 T- 0.828) portions of the song.

Fig. 14. Oscillograms of portions of duets between 3 A. monticola pairs (female upper trace, male lower trace). Echemes of the male are highlighted in red and the males’ ticks are highlighted in green. Female tick replies are highlighted in purple. Males’ songs are seen at lower amplitudes in the females’ traces (grey). Scale bar: 100 ms.

Fig. 15. Distributions of male (green) and female (purple) ticks in A. monticola as a function of the proportion of time between an echeme and the next echeme when a single tick or two ticks were emitted, (0.0–1.0) and (1.0–2.0), respectively. A. Schematic of the final portion of the calling song sequence with ticks (green) between groups of syllables (red) representing the echemes in the song. B. Overall distribution of male ticks in the song (green) including the mean ± SE (green circles) of single ticks (0.0–1.0) and double ticks (1.0–2.0). C. Same as in B but measured during duets with females. D. Distribution of female tick responses during the duets in C.