Yoyetta tristrigata (Goding & Froggatt, 1904)

Popple, Lindsay W. & Emery, David L., 2022, Five new species of Yoyetta Moulds (Hemiptera: Cicadidae: Cicadettinae) from south-eastern Australia, Zootaxa 5141 (5), pp. 401-441 : 439-440

Morphological key to species in the Y. tristrigata species group

Specimens must be set with wings spread to begin using this key. A vernier calliper is required to check measurements. Male specimens must often be examined microscopically and may require dissection in some instances.

1. Male specimen....................................................................................... 2

- Female specimen.................................................................................... 24

2. Median lobe of uncus exceptionally long, about as long as the distance between the apices of the upper pygofer lobe and dorsal beak................................................................................................ 3

- Median lobe of uncus short, not nearly as long as the distance between the apices of the upper pygofer lobe and dorsal beak 4

3. When viewed from dorsal side, black dorsal mark on tergite 3 extends laterally well beyond the upper margin of the timbal cavity; median lobe of uncus narrow at base, widest around mid length and tapering towards apex.......... Y. humphreyae

- Black dorsal mark on tergite 3 more confined, not overlapping laterally with the timbal cavity; median lobe of uncus narrow, slightly expanding distally, with rounded apex.................................................. Y. corindi n. sp.

4. Head width <5 mm .................................................................................... 5

- Head width ≥ 5 mm ................................................................................... 14

5. Thorax mainly brown.................................................................................. 6

- Thorax mainly black................................................................................... 8

6. Tergite 1 pale brown; pronotum mainly pale brown...................................................... Y. celis

- Tergite 1 black or dark brown; pronotum mainly brown or black................................................ 7

7. Fore wing length>20 mmm; cruciform elevation and surrounding areas adjacent to wing grooves all much paler and brighter than remainder of thorax...................................................................... Y. tristrigata

- Fore wing length <20 mm; cruciform elevation and surrounding areas adjacent to wing grooves not all distinctly paler than remainder of thorax........................................................................... Y. fluviatilis

8. Pronotum mainly brown, contrasting with mesonotum.................................. Y. tristrigata (dark specimen)

- Pronotum mainly dark brown to black, not distinctly paler than mesonotum....................................... 9

9. Lateral edges of tergites orange, with dark markings along posterior margin (broad or narrow, often diffuse)............ 10

- Lateral edges of tergites orange, without dark markings on posterior margin...................................... 11

10. Fore wing length usually> 20 mm; theca recurved distally through 180 degrees; apex weakly upturned..... Y. delicata n. sp.

- Fore wing length <20 mm; theca recurved distally through 120 degrees; apex downturned.................... Y. fluviatilis

11. Theca recurved distally through 180 degrees; apex straight or weakly upturned................................... 12

- Theca recurved distally through 120 degrees; apex straight or downturned....................................... 13

12. Fore wing length typically> 20 mm; apex of theca weakly upturned................................. Y. delicata n. sp.

- Fore wing length <20 mm; apex of theca straight................................................ Y. landsboroughi

13. Fore wing length> 20 mm; timbal long rib 4 appearing discontinuous, with dorsal and ventral areas connected by only a very narrow medial area........................................................................ Y. nigrimontana

- Fore wing length <20 mm; timbal long rib 4 clearly continuous, narrowing only slightly in medial area......... Y. fluviatilis

14. Timbal with four long ribs; fourth (anteriormost) long rib fused to the anterior cuticle..................... Y. ignita n. sp.

- Timbal with five long ribs, all separate from anterior cuticle and surrounded by pale timbal membrane................. 15

15. Timbal long rib 5 distinctly narrower than widest portion of adjacent long rib 4............................ Y. repetens

- Timbal long rib 5 about equal in width to adjacent long rib 4.................................................. 16

16. Thorax mainly brown to dark brown..................................................................... 17

- Thorax mainly black.................................................................................. 20

17. Fore wing length> 26 mm .................................................................. Y. robusta n. sp.

- Fore wing length <26 mm ............................................................................. 18

18. Cruciform elevation and surrounding areas adjacent to wing grooves all much paler and brighter than remainder of thorax............................................................................................. Y. tristrigata

- Cruciform elevation and surrounding areas adjacent to wing grooves not all distinctly paler than remainder of thorax..... 19

19. Length of body typically> 18 mm; tergite 2 black medially......................................... Y. cumberlandi

- Length of body <18 mm; tergite 2 orange with black restricted to anterior margin.............................. Y. celis

20. Tergite 2 mainly orange.......................................................... Y. tristrigata (dark specimen)

- Tergite 2 mainly black................................................................................ 21

21. Opercula relatively small, each <1.9 mm wide.................................................. Y. delicata n. sp.

- Opercula not relatively small, each ≥2.0 mm wide.......................................................... 22

22. Apex of theca very short lanceolate with a pair of upright basal lobes........................................... 23

- Apex of theca produced as a long spine with ornamentation and without a pair of upright basal lobes..... Y. australicta n. sp.

23. Pronotal collar brown; tergites 3–7 yellow-brown with black markings.................. Y. robusta n. sp. (dark specimen)

- Pronotal collar dark brown to black; tergites 3–7 orange with black markings............................ Y. robertsonae

24. Ovipositor sheath extends approximately 1 mm beyond apex of abdominal segment 9........................... Y. celis

- Ovipositor sheath extends <1 mm beyond apex of abdominal segment 9......................................... 25

25. Thorax mainly black.................................................................................. 26

- Thorax mainly brown (with black sigilla)................................................................. 33

26. Fore wing length> 27 mm ............................................................................. 27

- Fore wing length <27 mm ............................................................................. 29

27. Tergites 3–7 predominantly orange...................................................................... 28

- Tergites 3–7 predominantly black.............................................................. Y. robertsonae

28. Specimen from South Australia ............................................ Y. australicta n. sp. (larger specimens)

- Specimen from New South Wales .............................................................. Y. ignita n. sp.

29. Fore wing length <22 mm ............................................................................. 30

- Fore wing length> 22 mm ............................................................................. 32

30. Legs with fore and mid tibiae mainly dark ochraceous to black..................................... Y. nigrimontana

- Legs with fore and mid tibiae brown to orange-brown........................................................31

31. Eyes clearly red or dull red...................................................................... Y. fluviatilis

- Eyes not clearly red or dull red; instead black, brown, grey or faded..................... Y. landsboroughi , Y. fluviatilis *

32. Head width <5.2 mm ...................................................................... Y. nigrimontana

- Head width> 5.2 mm ........................................... Y. australicta n. sp., Y. delicata n. sp., Y. repetens *

33. Sternites with dark triangular central markings............................................................. 34

- Sternites without dark triangular central markings.......................................................... 35

34. Ovipositor sheath extends 0.5 mm – <1 mm beyond apex of abdominal segment 9......... Y. corindi n. sp., Y. humphreyae *

- Ovipositor sheath extends <0.5 mm beyond apex of abdominal segment 9............................ Y. robusta n. sp.

35. Ovipositor sheath extends 0.5 mm – <1 mm beyond apex of abdominal segment 9......... Y. corindi n. sp., Y. humphreyae *

- Ovipositor sheath extends <0.5 mm beyond apex of abdominal segment 9....................................... 36

36. Fore wing length> 27 mm .................................................................... Y. ignita n. sp.

- Fore wing length <27 mm ............................................................................. 37

37. Body length <17 mm, fore wing length <21 mm ..................................................... Y. fluviatilis

- Body length> 17 mm, fore wing length>21............................................................... 38

38. Thorax with cruciform elevation and surrounding areas adjacent to wing grooves distinctly paler and brighter than remainder of mesonotum............................................................................... Y. tristrigata

- Thorax with cruciform elevation and surrounding areas adjacent to wing grooves not noticeably paler than remainder of mesonotum........................................................................................... 39

39. Abdominal tergites 3–7 with black lateral markings clearly defined................................... Y. cumberlandi

- Abdominal tergites 3–7 with dull brown lateral markings diffuse and faded............................... Y. repetens

* These species cannot be reliably differentiated with female specimens alone. Male specimens are required. In some cases, checking information on geographical distributions may be helpful.