Uroptychus

Key to Australian species of Uroptychus

Updated from key by Ahyong & Poore (2004)

1. Rostrum about as broad as long......................................................................... 2

- Rostrum distinctly longer than broad..................................................................... 3

2. Anterior emargination of sternite 3 without pair of median spines. Antennal article 2 without small outer distal spine................................................................................ U. yokoyai Ahyong & Poore, 2004

- Anterior emargination of sternite 3 with pair of median spines. Antennal article 2 with small outer distal spine..................................................................................... U. alcocki Ahyong & Poore, 2004

3. Lateral margins of carapace smooth or crenulate............................................................. 4

- Lateral margins of carapace dentate or with distinct spines.................................................... 19

4. Carapace (excluding rostrum) distinctly broader than long..................................................... 5

- Carapace (excluding rostrum) as long as or longer than broad................................................ 10

5. Dactyli of pereopods 2–4 with 2 distal spines.............................................. U. pilosus Baba, 1981

- Dactyli of pereopods 2–4 with more than 8 spines or denticles along flexor margin................................ 6

6. Ultimate and penultimate articles of antennal peduncle each with distal spine..................................... 7

- Ultimate and penultimate articles of antennal peduncle without distal spine....................................... 8

7. Antennal article 2 with outer spine............................................... U. latus Ahyong & Poore, 2004

- Antennal article 2 without outer spine...................................... U. laperousazi Ahyong & Poore, 2004

8. Antennal scale overreaching apex of distal peduncle article. Antennal article 2 with small outer spine. Outer orbital angle acute.......................................................................... U. babai Ahyong & Poore, 2004

- Antennal scale reaching to about midlength of distal peduncle article. Antennal article 2 without outer spine. Outer orbital angle rounded....................................................................................... 9

9. Pereopod 1 about 3 times carapace length; dorsal margin of propodal palm about 2.5 times as long as dactylus. Spines lining flexor margin of dactyli longer than wide...................................... U. longvae Ahyong & Poore, 2004

- Pereopod 1 about 2 times carapace length; dorsal margin of propodal palm less than 2 times as long as dactylus. Spines lining flexor margin of dactyli about as long as wide................................... U. patulus Ahyong and Poore, 2004

10. Dactyli of pereopods 2–4 with 2 distal spines, or with 2 distal spines and a distantly separated group of minute spines oriented parallel to margin................................................................................... 11

- Dactyli of pereopods 2–4 with 7 or more spines along flexor margin........................................... 12

11. Dactyli of pereopods 2–4 with ultimate and penultimate spines close-set. Rostrum much shorter than eyestalks................................................................................................... U. albus sp. nov.

- Dactyli of pereopods 2–4 with ultimate and penultimate spines separated by distinct gap. Rostrum extending beyond eyestalks................................................................. U. thermalis Baba & de Saint Laurent, 1992

12. Spines lining flexor margin of dactyli oriented parallel to margin....................... U. australis (Henderson, 1885)

- Spines lining flexor margin of dactyli oriented oblique to margin.............................................. 13

13. Antennal scale reaching just over midlength of ultimate peduncle article........................................ 14

- Antennal scale almost reaching or exceeding apex of ultimate peduncle article.................................... 16

14. Propodi of pereopods 2–4 with single distal spine preceding row of spines on flexor margin. Dorsum with pair of small epigas- tric spines or tubercles...................................................... U. gracilimanus (Henderson, 1885)

- Propodi of pereopods 2–4 with paired distal spines preceding row of spines on flexor margin. Dorsum occasionally with pair of low epigastric scales but generally unarmed.............................................................. 15

15. Propodi of pereopods 2–4 with paired distal spines preceding 17–19 spines on flexor margin......... U. brucei Baba, 1986

- Propodi of pereopods 2–4 with paired distal spines preceding 4–5 setae on flexor margin................ U. jawi sp. nov.

16. Sternite 4 with field of granules on surface............................................................... 17

- Sternite 4 with single row of granules on surface............................................................ 18

17. Carapace (excluding the rostrum) slightly longer than broad. Merus of pereopod 4 0.8 times that of pereopod 3................................................................................................... U. bardi sp. nov.

- Carapace as long as broad. Merus of pereopod 4 about half-length that of pereopod 3.... U. empheres Ahyong & Poore, 2004

18. Carapace margins divergent, width between anterolateral margins 0.55 times that of broadest carapace width. Pereopod 1 robust; merus and ischium with distinct tubercles on inner proximal margin. Ultimate and penultimate spines of P2–4 dactyli subequal in width........................................................... U. litosus Ahyong & Poore, 2004

- Carapace margins subparallel or slightly divergent, width between anterolateral margins 0.7 times that of broadest carapace width. Pereopod 1 very slender; merus and ischium smooth. Uimimate spine of P2–4 dactyli narrower than penultimate spine..................................................................................... U. taylorae sp. nov.

19. Dorsum of carapace without spines, or with spines limited to lateral margins and gastric region...................... 20

- Dorsum of carapace covered with many large spines......................................................... 37

20. Lateral margin of carapace with single strong spine above base of first walking leg............... U. raymondi Baba, 2000

- Lateral margin of carapace with more than 1 lateral spine or tooth............................................. 21

21. Carapace very tuberculose/granulose on whole dorsal surface. Rostrum long and broad, length 2/3 of remaining carapace.. 22

- Carapace smooth on dorsal surface or with some tubercles. Rostrum usually less than 2/3 length of remaining carapace... 23

22. Carapace (including rostrum) 1.4–1.5 times as long as wide. Colour pattern orange with a single middorsal whitish band on the carapace and abdomen.............................................................. U. naso Van Dam, 1933

- Carapace 1.7–1.9 times as long as wide. Colour pattern with two longitudinal bands on the carapace and abdomen................................................................................. U. cyrano Poore & Andreakis, 2011

23. Penultimate article of antennal peduncle unarmed distally; length distinctly less than half that of ultimate article........ 24

- Penultimate article of antennal peduncle with distal spine; length half or greater than half that of ultimate article........ 25

24. Dorsum of carapace with pair of distinct epigastric spines. Carapace margins divergent and broadest in posterior quarter................................................................................. U. nigricapillis Alcock, 1901

- Dorsum of carapace smooth and unarmed. Carapace margins subparallel with distinct, bifid spine at base of cervical groove.......................................................................... U. flindersi Ahyong & Poore, 2004

25. Antennal scale bearing 1–3 lateral spines. Lateral margins of carapace and gastric region of carapace with small spinules. Car- apace length <6 mm............................................................. U. scandens Benedict, 1902

- Antennal scale without lateral spines. Lateral spines of carapace not spinule-like. Carapace length> 6 mm............. 26

26. Antennal scale reaching to about midlength of ultimate peduncle article. Ultimate antennal peduncle article unarmed distally................................................................................................. … 27

- Antennal scale almost reaching or exceeding apex of ultimate peduncle article. Ultimate antennal peduncle article with distal spine............................................................................................. 28

27. Carapace with dorsal spines on anterior region; lateral margins with 7 or more strong spines..................................................................................................... U. calcar Ahyong & Poore, 2004

- Carapace without dorsal spines; lateral margins with 4 or 5 small spines............ U. longicheles Ahyong & Poore, 2004

28. Lateral margins of carapace denticulate or with small spines.................................................. 29

- Lateral margins of carapace with strong spines............................................................. 32

29. Rostrum about two-thirds remaining carapace length; lateral margins with 2– 5 spinules; not dorsally excavated......... 30

- Rostrum half as long or less as remaining carapace; without lateral spinules (but can be distally trifid); dorsally excavated. 31

30. Carapace dorsum setose................................................... U. hesperius Ahyong & Poore, 2004

- Carapace dorsum naked.................................................. U. subsolanus Ahyong & Poore, 2004

31. Antennal scale overreaching ultimate peduncle article. Rostrum usually distally trifid.................................................................................................... U. multispinosus Ahyong & Poore, 2004

- Antennal scale extending almost to apex of ultimate peduncle article Rostrum never distally trifid.................................................................................................. U. joloensis (Van Dam, 1939)

32. Carapace with epigastric spines........................................................................ 33

- Carapace without epigastric spines...................................................................... 34

33. Dactylus of pereopods 2–4 with 8–10 strong spines on flexor margin. Dorsum of carapace smooth (except for epigastric spines)................................................................... U. zeidleri Ahyong & Poore, 2004

- Dactylus of pereopods 2–4 with 16–20 small spines on flexor margin. Dorsum of carapace rugose, setose......................................................................................... U. cardus Ahyong & Poore, 2004

34. Carapace with 4 lateral spines (excluding anterolateral spine). Propodi of pereopods 2–4 with only a pair of distal spines on flexor margin............................................................... U. belos Ahyong & Poore, 2004

- Carapace with 5–10 lateral spines (excluding anterolateral spine). Propodi of pereopods 2–4 with pair of distal spines and 1 or more preceding spines on flexor margin................................................................. 35

35. Carapace with 5–6 lateral spines (excluding anterolateral spine). Propodus of pereopod 2 with pair of distal spines and single preceding spines on flexor margin............................................ U. oxymerus Ahyong & Baba, 2004

- Carapace with 6–10 lateral spines (excluding anterolateral spine). Propodi of pereopod 2 with pair of distal spines and 4 or more preceding spine on flexor margin.................................................................. 36

36. Dactylus of pereopods 2–4 with 9–11 triangular spines on flexor margin. Pereopod 1 stout, about 2.5 times carapace length...................................................................... U. paracrassior Ahyong & Poore, 2004

- Dactylus of pereopods 2–4 with 14–16 closely spaced, slender, blunt spines on flexor margin. Pereopod 1 slender, more than 3 times capapace length.................................................................. U worrorra sp. nov.

37. Rostrum with several small lateral spines. Antennal scale almost reaching distal end of ultimate peduncle article......................................................................................... U. ciliatus (Van Dam, 1933)

- Rostrum with 2–3 pairs of prominent lateral spines. Antennal scale overreaching distal end of penultimate peduncle article........................................................................ U. spinirostris (Ahyong & Poore, 2004)