Trigonidium (Trigonidium) australianum ( Chopard, 1925 )

Hegg, Danilo, 2024, Small crickets of New Zealand (Orthoptera: Grylloidea: Trigonidiidae and Mogoplistidae), with the description of two new genera and species, European Journal of Taxonomy 955 (1), pp. 1-87 : 64-66

Trigonidium (Trigonidium) australianum ( Chopard, 1925)

Figs 31 , 32E–F

Metioche australiana Chopard, 1925: 36 .

Trigonidomorpha sjostedti Chopard, 1925: 40 syn. nov.

Trigonidomorpha areolata Chopard, 1925: 38 syn. nov.

Metioche australiana – Chopard 1968: 334.

Metioche areolata – Chopard 1968: 334.

Trigonidium australiana – Otte & Alexander 1983: 228.

Trigonidomorpha sjostedti – Otte & Alexander 1983: 223. — Rentz & Su 2019: 316.

Trigonidium (Trigonidium) australiana – Rentz & Su 2019: 304.

Amended diagnosis

A small trig (body length 4 to 5 mm), with black body and yellow legs, very similar to Trigonidium (Trigonidium) maoricum in every aspect. Slightly smaller than the latter, it has a shorter stridulatory file with less than 20 teeth. Adult insects come in a wingless morph without hindwings or auditory tympana, and in a winged morph with hindwings and with auditory tympana. The winged morph was previously mistaken to be a different species, Trigonidomorpha sjostedti .

Etymology

The Latin adjective australianum refers to the country the insect is found in.

Material examined

AUSTRALIA • 1 ♂, 1 ♀; Queensland, Brisbane, Oxley Creek Commons ; 27.53566° S, 152.99306° E; 10 m a.s.l.; 17 Nov. 2023; D. Hegg leg.; in tall grass; insect net; MPN OR0403 , OR0405 • 1 ♂; same data as for preceding; GenBank: PP761115 ; MPN OR0402 • 1 ♀; same data as for preceding; GenBank: PP761116 ; MPN OR0404 .

Description

Not included in this paper since this is not a New Zealand species.

MEASUREMENTS. See Table 7 .

Distribution

Australia. Northern, eastern and western coastal regions.

Figures

Fig. 31. Gene tree for Trigonidium Rambur, 1838 using Maximum Likelihood analysis of ~700 bp of mtDNA (COI) from 23 specimens and 1000 bootstrap replications. The tree with the highest log likelihood (-3571.04) is shown. Numbers next to the branches indicate the percentage of trees in which the associated taxa are clustered together. The tree is drawn to scale, with branch lengths measured in the number of substitutions per site. Specimens in blue were collected as part of this study; the remaining 15 sequences were obtained from the GenBank (Benson et al. 2013) and BOLD (Ratnasingham & Hebert 2007) databases. Detailed information for each specimen included in this analysis can be found in Supp. file 1: Table S11.

Fig. 32. Live trigs (subfamily Trigonidiinae). A–D. Trigonidium (Trigonidium) maoricum (Walker, 1869). New Zealand. A. Adult ♂, Tumbledown Bay, Banks Peninsula. B. Adult ♂, Kerikeri, Northland. C. Adult ♀, Māhoe Reserve, Lincoln. D. Fully winged adult ♀. Kerikeri, Northland. E–F. Trigonidium (Trigonidium) australianum (Chopard, 1925). Oxley Creek Commons, Brisbane, QLD, Australia. E. Adult ♀. F. Adult ♂. Note: all specimens are posed on unnatural backgrounds in captivity.