Kosciuscola tristis Sjöstedt, 1934 (tristis Sjostedt (Rehn, 1957)

Song, Hojun, Muschett, Giselle R., Woller, Derek A., Slatyer, Rachel A., Tatarnic, Nikolai J. & Umbers, Kate D. L., 2021, Taxonomic notes on the Australian skyhopper genus Kosciuscola Sjöstedt (Orthoptera: Acrididae: Oxyinae), Zootaxa 5071 (1), pp. 118-130 : 120-125

Kosciuscola tristis Sjöstedt, 1934 stat. rev.

( Figs. 1A, 1B , 2 , 3 , 4 )

Kosciuscola tristis Sjöstedt ( Sjöstedt, 1934, 26(9):6)

Kosciuscola tristis Sjöstedt (Sjöstedt, 1935, 15(2):79)

Kosciuscola tristis Sjöstedt ( Key & Day, 1954a, 2(3):309-339)

Kosciuscola tristis tristis Sjöstedt ( Rehn, 1957: 209)

Kosciuscola tristis Sjöstedt ( Filshie et al., 1975, 21(11): 1763-1770)

Kosciuscola tristis Sjöstedt ( Key, 1986, 24:9)

Kosciuscola tristis Sjöstedt ( Rentz, 1996, 178-179)

Kosciuscola tristis Sjöstedt ( Rentz et al., 2003: 75)

Kosciuscola tristis Sjöstedt ( Umbers, 2011, 57:1198-1204)

Kosciuscola tristis Sjöstedt ( Umbers et al., 2013a, 67:439-447)

Kosciuscola tristis Sjöstedt ( Umbers et al., 2013b, 59:81-90)

Kosciuscola tristis tristis Sjöstedt ( Tatarnic et al., 2013, 27:307-316)

Kosciuscola tristis tristis Sjöstedt (Slatyer et al., 2014, 14:204)

Kosciuscola tristis Sjöstedt ( Umbers et al., 2021)

Diagnosis. This species can be easily distinguished from other species of Kosciuscola by its turquoise blue coloration in males (in live specimens and body temperature over 25°C), swollen head in males, and triangular prosternal process in both sexes. It can be distinguished from K. restrictus by having a more robust body form, larger and more inflated head, especially across the genae, and more robust and somewhat swollen femora. This species shows temperature-dependent color change in males and is only found in the NSW alps.

Redescription. Coloration: Male head turquoise blue (when alive and body temperature over 25°C). Eye dark brown/black. Antennae tan. Male pronotum uniformly turquoise blue (when alive and body temperature over 25°C) without any distinct pattern ( Figs. 1A , 2A, 2B, 2D, and 2E ). Male tegmina light yellow dorsally, blackish green laterally. Legs brownish yellow, with slightly reddish knee in hind femur ( Figs. 1A , 2A, 2B ). Female head variable, ranging from mostly brown with black marking dorsally, to pink and green or uniform green. Female pronotum green/brown dorsally ( Fig. 1B ), lateral carina cream color, lateral portion of prozona black with patches ( Fig. 2I ). Female tegmina creamy white dorsally, black laterally. Female abdomen light yellow dorsally, laterally black ( Fig. 2J ).

Head: Median carinula of fastigium faintly present ( Fig. 2E ). Fastigial furrow obvious and softly indented and slightly tapering anteriorly ( Fig. 2E ). Anterior apex of fastigium from dorsal view broad. Frontal ridge raised past frontal suture, nearing clypeus ( Fig. 2C ). Median portion of frontal ridge slightly depressed below ocellus ( Fig. 2C ). Preocular ridge distinct and reaching clypeus. Subocular ridge deeply grooved. Frontal integument slightly rugose. Gena in male distinctly bulging and appearing swollen ( Fig. 2D ).

Thorax: Pronotum ( Fig. 2D, 2E ): Shape of anterior margin of pronotum slightly convex toward head. Anterior margin of prozona somewhat constricted to form a distinct ridge along the margin. Lateral carina constricted as distinct ridges. Dorsal profile of lateral carina clearly widening toward posterior end. Lateral lobes from dorsal angle not bulging out. Texture of dorsal surface slightly matted. Anterior sulcus of prozona faint. Anterior sulcus of prozona not touching median carina. Anterior sulcus extending to lateral lobe ending before touching lateral carina. Posterior sulcus of prozona not touching median carina. Posterior sulcus extending to lateral lobe extending down to lateral lobe. Posterior margin of metazona slightly incurved. Texture of dorsal surface of metazona lightly rugose. Texture of lateral lobe of prozona slightly rugose. Prosternal process ( Fig. 2H ): Triangular and narrowing toward apex. Tegmina ( Fig. 2D ): Dorsal profile formed by the area above subcosta wide. Lateral profile dorso-ventrally wide. Posterior apex from lateral view dorsally projecting more than ventrally.

Abdomen: Dorsal surface of first and second abdominal segment lateral ridges absent. Male cerci ( Fig. 2F, 2G ): Lateral view of male cercus simple and triangular, tapering toward apex. Length of male cercus shorter than epiproct. Dorsal view of male cercus simple, conical. Male furcula ( Fig. 2G ): Dorsal view of furcula round and distinct. Space between furcula lobes as wide as a single lobe. Male epiproct ( Fig. 2G ): Ridge along lateral margin of epiproct thickened and curved inwardly in the middle. Lateral plates of epiproct no concavity. Posterior apex of epiproct broadly projecting forward. Male subgenital plate ( Fig. 2G ): Apex of male subgenital plate simple and round. Female subgenital plate: Postvaginal sclerite absent.

Male genitalia: Epiphallus ( Fig. 3G, 3H ): Shape of ancorae short and broadly tapering toward apex inwardly. Anterior projection not bulbous. Lophi in dorsal profile distinctly bilobed, with lateral lobe projecting more than mesal lobe. Inner side of lateral plates not projecting. Shape of lateral lobe of lophi quadrate. Shape of mesal lobe of lophi quadrate. Space between mesal and lateral lobe of lophi narrow. Width of a single lophus distinctly narrower than half plate. Base of lophi distinctly angular to bridge. Height of lateral plate inner margin much narrower than outer margin. Shape of lateroventral plate not expanding. Outer side of lateroventral plate straight. Ectophallic sclerite ( Fig. 3F ): Two halves simply meeting in the middle. Membrane connecting epiphallus and cingulum membranous ( Fig. 3A, 3B ). Cingulum: Shape of rami not projecting ( Fig. 3C, 3D ). Dorsal aedeagal sclerite of endophallus elongate and tapering toward apex, with inner side straight and outside curved ( Fig. 3C, 3E ). Ventral aedeagal sclerite of endophallus simple rod-shape and shorter than dorsal aedeagal sclerite. Apodemes of cingulum broad and curve outward, and not reaching the end of endophallus.

Female genitalia: Dorsal sclerite of the bursa absent. Spermatheca apical arm much shorter than apical diverculum.

Measurements (in mm). Body length to end of hind femur: 17.77 1.33 (male, n = 10), 26.44 2.24 (female, n = 10); hind femur length: 11.43 0.5 (male, n = 10), 16.14 1.02 (female, n = 10).

Type. Lectotype female ( ANIC, Fig. 4A, 4B, 4C ). / Kosciusko Feb 1918 M. Fuller / Kosciuscola tristis Sjst n. gen. et. n. sp. ♀ Yngve Sjstedt det. / Typus / Measured specimen Rehn 1954 / Kosciuscola tristis tristis Sjst. ♀ Det. J.A.G. Rehn, 1955 / Lectotype ANIC 8762 Kosciuscola tristis Sjst., 1934 ♀ designated by J.A.G. Rehn, 1957 / ANIC Database No. 14 008606 /

Additional material examined. ANIC. 1 male: 4 mls S.W. of Hotel Kosciusko, N.S.W. 5360-5508 ft K.H.L. Key 6-3-46 ; 1 male: Dead Horse Gap , 3 mi. WSW of Thredbo, N.S. W. 5190 ft. 25.iii.1967 K.H.L. Key; 1 male and 2 females: N.S.W. Mt. Kosciusko , 7300 ft. (Summit) 18-4-37. K.H.L. Key ; 1 male and 1 female: Mt. Kosciusko. N S W 7328- 6850 ft. 5-3-46 K.H.L. Key ; 1 female: 36.22S 148.29E Dainers Gap , Kosciusko Nat. Park, N.S.W. 1650m. 14.ii.1978 J. Balderson; 1 male: 36.32S 148.15E Dead Horse Gap, Kosciusko Nat. Park, N.S.W. 1560m 19-ii-78 J. Balderson; 1 male: 36.17S 148.22E Schlink Pass , Kosciusko Nat. Park, N.S.W. 1800m. 20.iii.1979 D.C.F. Rentz, R.C. Lewis & E.C. Zimmerman Stop 13 . ANSP. 3 males and 4 females: N.S.W. Mt. Kosciusko, 7300 ft. (Summit) 18-4-37. K.H.L. Key ; 1 male: Mt. Kosciusko. N S W 7328- 6850 ft. 5-3-46 K.H.L. Key ; 1 male: 4 mls S.W. of Hotel Kosciusko N.S.W. 5360-5508 ft. K.H.L. Key 6-3-46; 1 female: Charlotte Pass Kosciusko Massif , N.S.W. 6036 ft. 5.3.46, K.H.L. Key . TAMUIC. 12 males and 8 females: Australia: NSW Thredbo Along Merrit's Nature Track S3629.595' E14817.383' 11ft. Elev. 6104 ft. 5-ii-2013. Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 12 males and 4 females: Australia: NSW Thredbo Near lift off to Merrit's Trail S 3629.669' E14817.293' 9ft. Elev. 6305 ft. 5-ii-2013. Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 4 males and 5 females: Australia: NSW Thredbo. Top of Deadhorse Gap. elev 6181ft. S3850.148' E14827.283' 10-ii-2013 Coll . R Slatyer ; 1 male: Australia: NSW, Jindabyne Rainbow Lake Walk, elev. 5238ft. S 3622'11.8 E14828'27.8 17-ii-2013. Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 1 male and 1 female: Australia: NSW, Kosciusko NP Along Cascade Trail elev. 5326ft. S3631.738' E14816.160' 9-ii-2013 Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 1 female: Australia: NSW, Kosciusko NP Beginning of Cascade Trail elev. 5180ft. S3631.569' E14815.931' 14ft. 9-ii-2013 Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett Dissected genitalia ; 7 males and 4 females: Australia: NSW, Kosciusko NP Charlotte Pass Caf elev. 5925ft. S3624'56.6 E14823'30.4 17-ii-2013 Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 30 males and 16 females: Australia: NSW, Kosciusko NP Mt. Tate, from Guthega Trail S 3622.388' E14821.940' 9ft elev. 5396ft. 15-ii-2013 Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 3 males: Australia: NSW, Thredbo Along Merrit's Nature Track S3629.719' E14817.703' 9ft. Elev. 5517 ft. 5-ii-2013. Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 2 males and 3 females: Australia: NSW, Thredbo Along Merrit's Nature Track S3629.965' E14817.877' 9ft. Elev. 5147 ft. 5-ii-2013. Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 19 males and 5 females: Australia: NSW, Thredbo Along Thredbo Trail elev. 5469ft. S3631.118' E14815.824' 9ft. 4-ii-2013 Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 9 males and 1 female: Australia: NSW, Thredbo Along Thredbo Trail elev. 5762ft. S3630.744' E14816.019' 9ft. 4-ii-2013 Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett ; 23 males and 5 females: Australia: NSW, Thredbo Raven's Haunt, elev. 6389ft. S3630'05.6" E14816'22.4" 4-ii-2013 Coll. H. Song, K. Umbers, N. Tatarnic, G. Muschett.

Biology and ecology. This species can be found in the grassy understory in the subalpine and alpine regions. Its diet includes a wide variety of alpine grasses, including several species of Poa spp. , Deschampsia spp. and Carex spp. (Umbers et al., 2013). This species is univoltine – adults do not overwinter but lay eggs in summer and autumn, which may hatch the following spring or may partially develop in the first summer and emerge in their second spring. The hatchlings typically emerge in late October, and after going through several molts, adults emerge in January. The mating season lasts through April and females can be seen ovipositing from March to May ( Dearn, 1977; Tatarnic et al., 2013; Umbers et al., 2013). This species does not appear to have any pre-copulatory courtship behavior, but males engage in fierce combat over ovipositing females, and they will frequently grapple, bite and kick their opponent and perform ritualized mandible flaring ( Umbers et al., 2012).

Distribution. Kosciuscola tristis inhabits the highest elevations in the Kosciuszko Massif and is rarely found below 1500 m. Specifically, it is commonly found in the NSW alps, including Mt. Kosciuszko, Mt. Townsend, Mt. Tate, and Mt. Jagungal.

Figures

FIGURE 1. A. Kosciuscola tristis male; B. K. tristis female; C. K. restrictus male; D. K. restrictus female (Photo credit: Hojun Song)

FIGURE 2. Kosciuscola tristis (typical specimens).A. lateral view of the whole body (male); B. dorsal view of the whole body (male); C. frontal view of the head (male); D. lateral view of the head and thorax (male); E. dorsal view of the head and thorax (male); F. lateral view of male terminalia; G. dorsal view of male terminalia; H. prosternal process; I. lateral view of the whole body (female); J. dorsal view of the whole body (female).

FIGURE 3. Male genitalia of Kosciuscola tristis. A. dorsal view of the phallic complex; B. frontal view of the phallic complex; C. dorsal view of cingulum and endophallus; D. frontal view of cingulum and endophallus; E. lateral view of cingulum and endophallus; F. frontal view ectophallic sclerite; G. frontal view of epiphallus; H. dorsal view of epiphallus. (scale = 1 mm).

FIGURE 4. Lectotype of Kosciuscola tristis (ANIC). A. lateral view; B. dorsal view; C. labels.