Pterapotrechus salomonoides ( Karny, 1929 )
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publication ID |
https://doi.org/10.3897/jor.34.134391 |
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publication LSID |
lsid:zoobank.org:pub:C645C740-6720-444F-875A-624D4E0C46F4 |
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DOI |
https://doi.org/10.5281/zenodo.14927175 |
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persistent identifier |
https://treatment.plazi.org/id/2DB07B91-2A5F-5799-ADDC-07E5296D885B |
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treatment provided by |
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scientific name |
Pterapotrechus salomonoides ( Karny, 1929 ) |
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Pterapotrechus salomonoides ( Karny, 1929) View in CoL
Figs 3 View Fig. 3 , 4 View Fig. 4 , 5 View Fig. 5 , 6 View Fig. 6 , 7 View Fig. 7 , 8 View Fig. 8 , 9 View Fig. 9 , 10 View Fig. 10 , 11 View Fig. 11 , 12 View Fig. 12 , 13 View Fig. 13
Paragryllacris salomonoides Karny, 1929: 14. View in CoL
Pterapotrechus salomonoides View in CoL — Karny 1937: 73. — Cadena-Castañeda 2019: 99.
Diagnosis. —
P. salomonoides is the smaller of the two species in the genus Pterapotrechus (Fig. 4 View Fig. 4 ). Body usually shorter than 30 mm. Tegmina always shorter than 30 mm. Ovipositor short (<20 mm) and strongly recurved upwards (Fig. 9 F View Fig. 9 ). Frons black (Fig. 6 B View Fig. 6 ). Female subgenital plate bilobed (Fig. 9 E View Fig. 9 ). Male subgenital plate triangular, bearing numerous dense, stout spinules on the median keel underneath (Fig. 9 B, C View Fig. 9 ).
Habitat and distribution. —
Coastal forests in southern Queensland and northern New South Wales, Australia. Introduced by anthropogenic means and naturalized in North Island, New Zealand.
Etymology. —
Named for its resemblance to katydids in the genus Salomona Blanchard, 1853 ( Karny 1929). ‘ Salomonoides ’ is an adjective of the third declension.
Material examined. —
( See also Suppl. material 1: table S 1) Holotype: AUSTRALIA • ♀; Queensland, Tamborine Mountain ; 27.9°S, 153.2°E; 500 m. a. s. l.; 1910–1913; E. Mjöberg leg.; NRM ORTH 0000231 View Materials . GoogleMaps
Representative male: AUSTRALIA • 1 ♂; Queensland, Tamborine Mountain, MacDonald Rainforest Circuit ; 27.91845°S, 153.20455°E; 500 m. a. s. l.; 15 Nov. 2023; D. Hegg leg.; rainforest, in foliage; insect net; QM T 260852 GoogleMaps .
Other material. AUSTRALIA – Queensland ( QLD) • 1 ♀; Tamborine Mountain, MacDonald Rainforest Circuit ; 27.91845°S, 153.20455°E; 500 m. a. s. l.; 15 Nov. 2023; D. Hegg leg.; rainforest, in foliage; insect net; GenBank: PP 971680; MPN OR 0548 GoogleMaps • 1 ♀; Tamborine Mountain, Esme Lahey Environmental Park ; 27.94776°S, 153.19386°E; 530 m. a. s. l.; 13 Nov. 2023; D. Hegg leg.; rainforest, in foliage; insect net; GenBank: PP 971677; MPN OR 0546 GoogleMaps • 1 ♂; same collection data as for preceding; MPN OR 0547 GoogleMaps • 1 ♂; Springbrook NP, Purling Brook Falls ; 28.18950°S, 153.27177°E; 600 m. a. s. l.; 18 Nov. 2023; D. Hegg leg.; in park map display case; insect net; GenBank: PP 971678; MPN OR 0543 GoogleMaps • 1 ♂; same collection data as for preceding; MPN OR 0549 GoogleMaps • 1 ♀; Binna Burra ; 28.19925°S, 153.18819°E; 820 m. a. s. l.; 14 Nov. 2023; Rainforest, D. Hegg leg.; rainforest, in foliage; insect net; GenBank: PP 971679; MPN OR 0544 GoogleMaps • 1 ♂; same collection data as for preceding; MPN OR 0545 GoogleMaps . NEW ZEALAND – Auckland (AK) • Helensville, Mangakura Road ; 36.69°S, 174.45°E; 20 m. a. s. l.; 13 Jan. 2021; N. Clayton leg.; inside house; jar; MPN OR 0440 GoogleMaps • 4 ♂♂, 1 ♀; Tahuna Torea Reserve ; 36.87169°S, 174.88205°E; 0 m. a. s. l.; 23 Nov. 2023; D. Hegg leg.; native forest, in foliage; insect net; MPN OR 0535 to OR 0538 , OR 0533 GoogleMaps • 1 ♀; same collection data as for preceding; GenBank: PP 971675; MPN OR 0544 GoogleMaps . – Northland (ND) • 1 ♂; Kerikeri ; 35.21570°S, 173.96044°E; 20 m. a. s. l.; 21 Nov. 2021; D. Hegg leg.; native forest, in foliage; insect net; MPN OR 0541 GoogleMaps • 1 ♂; Kerikeri ; 35.21797°S, 173.95276°E; 20 m. a. s. l.; 29 Nov. 2021; D. Hegg leg.; native forest, in foliage; insect net; MPN OR 0539 GoogleMaps • 1 ♀; Kerikeri ; 35.21649°S, 173.96051°E; 20 m. a. s. l.; 13 Dec. 2022; native forest, in foliage; insect net; MPN OR 0540 GoogleMaps • 1 ♀; same collection data as for preceding; GenBank: PP 971676; MPN OR 0542 GoogleMaps .
Description. —
Karny’s (1929) original description of the species (see Suppl. material 1: appendix A) is for the adult female only. The male was never described. While Karny’s description is minutiously accurate, it is wordy and hard to follow with few illustrations. Curiously, it lacks any mention of the stridulatory apparatus, which in Gryllacrididae is present in both males and females.
A new description of the species is given here, based on the examination of 19 fresh specimens, and including a description of the male for the first time.
Measurements. See Table 1 View Table 1 . Females tend to be slightly larger than males, but not significantly so.
Head. (Fig. 6 A, B View Fig. 6 ). No noticeable sexual dimorphism. Vertex heavily domed, glabrous, smooth, and shiny, pale. Median ocellum visible as a white dot. Just below the ocellum, a shallow V-shaped line separates the pale fastigium from the black frons. The latter is wrinkled throughout and is delimited on the sides by prominent ridges running from the insertions of the antennae to the base of the mandible; these ridges are diagnostic of the genus Pterapotrechus . Mandibles very strong, sharp. Labrum and mandibles dark red / brown. Labial and maxillary palpi pale. Antennae uniform brown, very long, four times the body length or more.
Thorax. Pronotum pale; reddish-brown only near the margins. Anterior margin convex in the middle; posterior margin straight. Anterior corners of the lateral lobes in the shape of sharp right angles; posterior corners truncated. A straight median sulcus and two curved sulci on either side of the pronotal discus give the pronotum a characteristic dorsal pattern (Fig. 6 D View Fig. 6 ). Dark markings on parts of the sulci are often present but not in all individuals.
Wings. (Fig. 7 View Fig. 7 ). Fore- and hindwings well developed in adult males and females. Forewings truncated in apical half, shaped like the blade of a kayak paddle; shorter than body, yet always reaching beyond the end of the abdomen; falling well short of the apex of the ovipositor in females (Fig. 10 B View Fig. 10 ). Hindwings on average 6 % longer than the forewings. Wing shape as in Chauliogryllacris acaropenates Rentz et al., 2018 and in Béthoux 2012: Fig. 16. Wing venation simpler than in most other Australian Gryllacrididae ( Béthoux 2012) , with veins CuA, CuPaα, and CuPaβ fused into a single vein in both forewing and hindwing. Veins MA and MP share the basal stem with RP in the hindwings.
Legs. Fore and mid femora approximately one-third of body length, unarmed. Fore and mid tibiae hairy above; armed ventrally with one pair of spines at the apex (Fig. 6 F View Fig. 6 ) and with four pairs of strong, sharp spurs that are articulated at the base (Fig. 6 F View Fig. 6 ; detail in Fig. 6 C View Fig. 6 ). Hind femora smooth inside, but with a scabrous stridulatory file near the dorsal edge in basal third (Fig. 8 C, D View Fig. 8 ); armed ventrally in distal half often but not always with one spine on inner edge, always with two to four spines on outer edge. Hind tibiae hairy above, unarmed in basal half (Fig. 6 G View Fig. 6 ); armed ventrally with one pair of spines near the apex; armed dorsally on both sides with two to four spines in distal half (Fig. 6 G View Fig. 6 ). Hind tibiae armed with three pairs of apical spurs, one dorsal and two ventral, the ventral spurs being recurved upwards.
Abdomen. Shape typical of other Gryllacrididae , with two rows of stridulatory pegs laterally on both tergites T 2 and T 3 (Fig. 8 A, B View Fig. 8 ). Peg counts in all four rows are reported in Table 1 View Table 1 .
Male terminalia. Internal male genitalia soft, non-sclerotized, as in most other Australian Gryllacrididae ( Rentz and John 1990, Rentz et al. 2018). Suranal plate pale, roughly trapezoidal, with two very prominent, darkened, cat’s ear-shaped lobes on the apical vertices (Fig. 9 A View Fig. 9 ). Subgenital plate triangular, bearing numerous dense, stout spinules on the median keel underneath (Fig. 9 B, C View Fig. 9 ).
Female terminalia. Subgenital plate glabrous, with two pointed lobes giving it the shape of a capital letter M (Fig. 9 E View Fig. 9 ). Ovipositor on average 60 % of body length, strongly recurved upwards (Fig. 9 F View Fig. 9 ).
Eggs. One female from Kerikeri, New Zealand ( MPN OR 0540) was dissected and found to be carrying 62 eggs in various stages of development. Mature eggs are yellow, elongated, between 4 mm and 4.5 mm long and approx. 1.5 mm wide at center (Fig. 9 G View Fig. 9 ).
Geographic distribution in New Zealand. —
As of mid- 2024, the known geographic distribution of Pterapotrechus salomonoides ( Karny, 1929) in New Zealand is centered around Auckland (36.9°S, 174.8°E) and extends northwards to Cable Bay, Northland (35.0°S, 173.5°E) and southwards to a line joining Raglan, Hamilton, and Tauranga (Latitude 37.5°S) (Fig. 11 View Fig. 11 ).
A total of 436 observations of Pterapotrechus salomonoides in New Zealand were recorded in the iNaturalist (https://www.inaturalist.org) database from 1 July 2012 to 30 June 2024. Ten of these observations were discarded for having obscured or private coordinates that could not be obtained. The remaining 426 observations are mapped in Fig. 11 View Fig. 11 . Two observations from this dataset were removed from the subsequent numerical analysis of the insect’s geographic distribution, since they appear to be outliers, and it could not be confirmed that a population has actually established at either of these locations. The observations discarded, shown as yellow dots in Fig. 11 View Fig. 11 , are from Te Kaha, Bay of Plenty, in October 2021 (iNaturalist 96763859), with coordinates that are possibly inaccurate, and from Taupō in July 2022 (iNaturalist 178798045). The insect in the latter observation was found in a campervan and had possibly just traveled from a different location.
The maximum diameter of the species’ geographic range in New Zealand has been increasing steadily since 2012 (Fig. 12 A View Fig. 12 ). A straight line with a slope of 36.96 km / year is a good fit for the observed data (R 2 = 0.94), indicating that the insect has been advancing at an average of 18.5 km per year in all directions.
The increase in land area occupied by the species’ geographic range (Fig. 12 B View Fig. 12 ) is best approximated by a second order polynomial (R 2 = 0.97), with a coefficient of the quadratic term equal to 271.8 (km / year) 2. If the region occupied by the insect were circular, this would be equivalent to the insect advancing at an average 271. 8 ÷ π = 9. 3 km per year in all directions. The discrepancy between the two numbers calculated here is easily explained by the constraints posed by New Zealand’s geography, which does not lend itself to being approximated with a simple geometrical shape.
Population density in the city of Auckland, New Zealand. —
In the city of Auckland, New Zealand, 352 Pterapotrechus salomonoides ( Karny, 1929) observations were recorded on iNaturalist (https://www.inaturalist.org) by 243 individual observers from 1 July 2012 to 30 June 2024. Numbers broken down by year are graphed in Fig. 13 View Fig. 13 .
The total number of P. salomonoides observations in Auckland increased from one per year in 2013 and 2014 to one hundred per year in 2024 (Fig. 13 A View Fig. 13 ). The total number of iNaturalist insect observations in Auckland also increased from 735 per year to 12,160 per year in the same time period. The percentage of P. salomonoides among all insect observations in Auckland increased six-fold from 0.14 % in 2013 to 0.81 % in 2024 (Fig. 13 C View Fig. 13 ).
The number of observers in Auckland who reported at least one P. salomonoides observation increased from one per year in 2013 to 85 per year in 2024 (Fig. 13 B View Fig. 13 ). The number of observers in Auckland who have reported at least one insect observation has also increased from 41 per year to 1,075 per year in the same time period. The percentage of P. salomonoides observers among all observers who have recorded at least one insect in Auckland has increased four-fold from 2.4 % in 2013 to 9.2 % in 2024 (Fig. 13 D View Fig. 13 ).
Dietary observations. —
Pterapotrechus salomonoides specimens held in captivity were omnivores. They readily consumed grated apple and appeared to ignore grated carrot and pet food. They hunted and ate a variety of nocturnal invertebrates including moths, crane flies, and Orthoptera , but seemed unable to detect diurnal Diptera that rest at night.
A list of the food choices offered to the captive Pterapotrechus salomonoides specimens, and whether they were consumed or ignored, is shown in Table 2 View Table 2 . Quantities eaten were not recorded.
| NRM |
Swedish Museum of Natural History - Zoological Collections |
| QM |
Queensland Museum |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
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Order |
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SubOrder |
Ensifera |
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InfraOrder |
Tettigoniidea |
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SuperFamily |
Stenopelmatoidea |
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Family |
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SubFamily |
Hyperbaeninae |
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Tribe |
Paragryllacridini |
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Genus |
Pterapotrechus salomonoides ( Karny, 1929 )
| Hegg, Danilo 2025 |
Pterapotrechus salomonoides
| Cadena-Castañeda OJ 2019: 99 |
| Karny HH 1937: 73 |
Paragryllacris salomonoides
| Karny HH 1929: 14 |