Australiagraecia Rentz, Su and Ueshima, 2021

Rentz, Dcf, Su, You Ning & Ueshima, Norihiro, 2021, Studies in Australian Tettigoniidae: New short-winged Agraeciini from Australia (Orthoptera: Tettigoniidae; Conocephalinae; Agraeciini), Zootaxa 5059 (2), pp. 1-72 : 8-10

Australiagraecia Rentz, Su and Ueshima Gen. et sp. nov.

ANIC Number Gen. Nov. 9

Type species: Australiagraecia spina Rentz & Su , gen. et sp. nov., here designated.

1 Named with reference to the distribution of species within the genus occurring across the southern portion of Australia: feminine gender.

Common name. Heath-loving Katydids

Australiagraecia is described to accommodate seven similar-appearing, ground-dwelling, micropterous katydids that occur in open woodland and heath habitats on both sides of the Australian continent. Where they occur, these katydids are usually common but very difficult to approach because of their wariness and considerable jumping capabilities. Shadows and the tangle of twigs and stems make it very difficult to follow escaping individuals. These katydids seem to be diurnal in many of their activities but this may be an artefact of collecting. The sound recordings we have made of the species described herein have been made at night see Rentz and Balderson, 1989). They are predaceous on small insects.

Although appearing similar in overall appearance, the species as here defined are very diverse in their genitalic composition. Because of their widespread distribution and apparent complex speciation, we do not yet fully understand this genus. Long-term collecting and study utilising karyotype and molecular information will be required to fully interpret this genus.

Australiagraecia seems to be most closely related to Ganiagraecia from which it differs in its less robust appearance, more “long-legged” habitus and the absence of a pair of lightly sclerotised straight rods on either side of the male phallic complex. These seem to be replaced by a much smaller, bifurcate process on each side.

Diagnosis. Head globular to slighting slanting; fastigium of vertex short but with minute median sulcus. Pronotum rather short, not covering most of male tegmina, cephalic and caudal margins about equal; lateral lobes relatively deep, the cephalic portion produced and covering half of the very large thoracic auditory spiracle. Tegmina of male macropterous, absent in females. Thorax with a pair of thick, widely-spaced spiniform processes; mesothorax bearing a prominent pair of almost erect tubular processes; metathorax with a similar but slightly larger pair of processes. Male abdomen not modified; tenth tergite with soft, shallow median incision; paraprocts short triangular projections seemingly not used in a clasping role; cerci highly species’ distinctive, ranging from incurved spiniform and needle-like to more traditional clasping organs; phallic complex almost entirely membranous, but with a pair of lightly sclerotised rods on each side; subgenital plate about as broad as long or longer than broad, apex with a shallow V-shaped incision, styles well indicated, about as long as each side of median incision, sparsely setose. Females apterous, abdomen elongate; tenth tergite short apically truncate; lateral portion of base of ovipositor with a “plate” on each side; subgenital plate varying in length and width with the species, apex narrowed and with a shallow notch. Ovipositor very elongate and gracefully upcurved, unarmed, much longer than length of body.

Colour almost uniform among the species, yellow brown with dark brown median stripe running from head to apex of tenth tergite, including the tegmen in males ( Figs 2A , 4A ). Tip of male abdomen often bright orange in life, this fading on museum specimens. In addition, almost all species are identical except of characteristics of the stridulatory file and male and female genitalia.

Generic description. Male/Female. Entire body shining, glistening. Head without carinae; frontal fastigium appearing absent or represented as a minute swelling bearing the median ocellus; antennae with scape quadrate, with tooth-like projection internally, pedicel short, cylindrical, about ¼ length of scape; flagellum thread-like, about 1.5 times the length of body, not usually annulate. Pronotum without any carinae; cephalic margin very faintly concave, caudal margin truncate to feebly concave; lateral lobe produced saddle-like in cephalic portion, caudal portion partially covering auditory opening; caudal margin of pronotum of male covering about ¼ to ½ of tegmina. Thoracic auditory tympanum large, elongate, only partially covered by pronotum. Tegmen thin, with a few elongate veins, mirror longer than broad and without internal venation. Foreleg with femur unarmed; tibia unarmed dorsally, ventral surface with 6 spines on each margin, the proximal three distinctly curved. Middle leg with femur bearing minute swellings or distinct teeth on internal margin of ventral surface; tibia armed dorsally with 1 or 2 widely spaced spines depending on species. Hind leg with femur armed ventrally only on internal margin; tibia armed dorsally with many small, close-set spines, ventrally with a much smaller number of more elongate spines; dorsal surface armed with a pair of subapical spurs, ventral surface with 2 apical spurs, one on each side. Fore femur with genicular lobes unarmed, middle and hind femora unarmed or hind femur with minute spine internally. All genicular lobes unarmed. Male tenth tergite little produced; supra-anal plate unmodified; modified paraprocts absent. Cerci ranging from short, stout, rectangular to very elongate and spiniform depending upon species. Phallus entirely membranous or with a lightly sclerotised rod on each side at base. Female with tenth tergite unmodified; supra-anal plate short, apically produced or not; cerci conical, rather stout, apically feebly directed inwards. Ovipositor with a plate-like structure on each side at base; longer than length of body, straight to gracefully upcurved, unarmed.

Key for the identification of known Australiagraecia species , based mainly on males

(Note: several species are sympatric with one another)

1 Occurring in South Australia and probably western Victoria ( Map 2 )..................................................................................................... A. spina Rentz, Su and Ueshima , sp. nov. (in part), p. 10

1’ Occurring in Western Australia .......................................................................... 2

2(1’) Males with an extraordinary development of cercus as an acute spine often directed inwards ( Fig. 2F ); phallic complex with a pair of slender rods at base ( Fig. 2H ), these shorter and forked in populations east of the Nullarbor Plain ( Map 2 ) and widespread in suitable heath habitats in southwest Western Australia ( Maps 1 , 2 )................................................................................... Australiagraecia spina Rentz, Su and Ueshima , sp. nov. (in part), p. 10

2’ Males with cercus not as exaggerated, not directed inwards and downwards at rest; phallus with varying degrees of sclerotization................................................................................................ 3

3(2’) Males with central portion phallus (median lobe) minutely shagreened........................................... 7

3’ Males with sclerotization of phallic complex, either as rods or minute sclerites; median lobe not shagreened............. 4

4(3’) Adults very small ( Table 1 ); male cerci needle-like, delicate, weakly directed inwards. (Known only from vicinity of Eneabba, Western Australia ( Map 3 )............................ Australiagraecia minuta Rentz, Su and Ueshima , sp. nov., p. 11

4’ Adults slightly larger ( Table 1 )........................................................................... 5

5(4’) Antennae annulate ( Fig. 6C ). Male cerci ( Fig. 6G ); phallic complex a pair of prominent pair of elongate, rounded lobes ( Fig. 6I ). Known from a relatively broad range of coastal and inland localities in Western Australia ( Map 3 ).................................................................... Australiagraecia tagera Rentz, Su and Ueshima , sp. nov., p. 14

5’ Antennae not annulate. Other characters not as above........................................................ 6

6(5’) Ovipositor extraordinarily long in comparison with the length of the body ( Table 1 ). (Widespread in south-western Western Australia from Mt Ragged, along the coast and inland ( Map 3 )..................................................................................................... Australiagraecia gladiator Rentz, Su and Ueshima , sp. nov., p. 15

6’ Ovipositor not as long as above ( Table 1 ).................................................................. 7

7(6’) Male phallic complex with basal sclerites present and divided ( Fig. 4E ). Known from broad region of south-west Western Australia (often sympatric with other Australiagraecia species , ( Map 1 )............................................................................................... Australiagraecia helleri Rentz, Su and Ueshima , sp. nov., p. 12

6’ Male phallic complex with a minute basal sclerite OR central phallic lobe minutely shagreened....................... 7

7(6’) Male cercus, short, robust with small external tooth ( Figs 5D, E ); phallic complex with a minute basal sclerite ( Fig. 5G ). Known from a single locality near Albany, Western Australia ( Map 3 )................................................................................................ Australiagraecia torndirrupa Rentz, Su and Ueshima , sp. nov., p. 13

7’ Male cercus robust and oddly curved (Fig. 8A); phallic complex with a minutely divided sclerite at base. Known from a few inland localities west of Kalgoorlie, Western Australia ( Map 3 )................................................................................................. .. Australiagraecia curvata Rentz, Su and Ueshima , sp. nov., p. 16

Figures

FIG. 2. Australiagraecia spina WA. A. Adult female, dorsal view. B. Adult female, ventral view of thorax. Note armature of thoracic segments. C. Adult female, lateral view of head and pronotum. Note transverse sulcus. D. Adult female, ventral view subgenital plate. E. Adult male, tip of abdomen. Note elongate supra-anal plate with median sulcus. Anus and phallic complex slightly everted. F. Left cercus, adult male. G. Left tegmen, male. Note, setation. The brown area is part of the median stripe that extends for the entire length of the insect. H. Phallic complex. Note divided minute rods at base. I. Adult male, tip of abdomen. J. Adult female, tip of abdomen, dorsal view.

FIG. 4. Australiagraecia helleri. A. Holotype male, dorsal view. B. Holotype male, tip of abdomen. Note broad supra-anal plate. C. Left male cercus. D. Holotype male, tip of abdomen ventral view. Note elongate styles of subgenital plate. E. Phallic complex. Note divided rod-like sclerites at base.

MAP. 2.

MAP. 1.

MAP. 3.

FIG. 6. Australiagraecia tagera. A. Male frons. B. Male thorax. Note structure of thoracic pegs including slender prosternal spines. C. Antenna. Note annulations. D. Lateral view left portion of female abdominal apex. Note swelling that might be relevant to placement of male cercus during mating. E. Ventral view female abdomen. Note relatively broad subgenital plate. F. Ventral view male abdomen. Note partially everted phallic complex. G. Left male cercus. H. Left male tegmen. I. Male phallic complex everted. Note slightly divided median lobe lacking minute tubercles. J. Right hind leg, female. Note spination. K. Male abdomen, ventral view with phallic complex slightly everted. Note digitiform lateral lobes.

FIG. 5. Australiagraecia torndirrupa. A. Male abdomen, dorsal view. Note broad supra-anal plate with broad median depression. B. Male abdomen, left cercus removed. Note lateral tooth of cercus and paraprocts. C. Left male tegmen. D. Left male cercus, internal view. E. Left male cercus, dorsal view. F. Dorsal view holotype male, left cercus removed. G. Phallic complex. Note shagreened apex of median lobe. H. Male abdomen ventral view. Note short styles of subgenital plate. I. Right hind tibia internal view. Note spurs and spines.