Galatheidae Samouelle, 1819

Rodríguez-Flores, Paula C., Macpherson, Enrique & Machordom, Annie, 2021, Revision of the squat lobsters of the genus Phylladiorhynchus Baba, 1969 (Crustacea, Decapoda, Galatheidae) with the description of 41 new species, Zootaxa 5008 (1), pp. 1-159 : 6-9

Family Galatheidae Samouelle, 1819

Genus Phylladiorhynchus Baba, 1969

Phylladiorhynchus Baba, 1969: 3 .— Baba, 2005: 200.— Baba et al., 2008: 175.— Baba et al., 2009: 286.— Macpherson & Baba, 2011: 55.— Schnabel & Ahyong, 2019: 304.

Type species. Galathea pusilla Henderson, 1885 , by original designation.

Diagnosis. (Modified after Macpherson & Baba 2011; Schnabel & Ahyong 2019) Carapace dorsally unarmed or with few epigastric spines, rarely with parahepatic spines, with distinct transverse ridges; lateral margin spinose. Rostrum triangular, dagger-shaped, leaf-like or bottle-shaped, usually with well-developed supraocular basal and subapical spine on each side, margin usually minutely serrated. Lateral orbital spine always present. Thoracic sternite 3 with posterior margin widely or narrowly contiguous to sternite 4. Telson subdivision incomplete, composed of ten plates. Eyes movable; cornea usually as wide as peduncle. Antennular article 1 with 3–5 distal spines (nearly always including double distolateral spine). Antennal article 1 with strong ventral distomesial process usually overreaching antennal article 4. Mxp3 ischium with distal spines, crista dentata with row of spines along entire margin; merus much shorter than ischium, with strong spines on flexor and extensor distal margins. G1 absent; G2 present. P1 spinose, fingers distally with row of spines along curved margin, tip excavated, spooned.

Key to species of the genus Phylladiorhynchus

1. Epigastric ridge of carapace unarmed..................................................................... 2

- Epigastric ridge of carapace with spines................................................................... 6

2. Pterygostomian flap with small spine on upper margin................................... P. nudus Macpherson, 2008

- Upper margin of pterygostomian flap unarmed.............................................................. 3

3. Anterior branchial margin of carapace with 2 spines. Proximal half of rostrum margin straight, distal half convex (bottle- shaped).................................................................................. P. phlias n. sp.

- Anterior branchial margin of carapace with 3 spines. Rostrum margin slightly convex............................... 4

4. Anterior epigastric ridge distinct and medially interrupted. Thoracic sternite 3 laterally projected........ P. jeffkinchi n. sp.

- Anterior epigastric ridge usually undistinct, or scale-like. Lateral angles of thoracic sternite 3 not projected.............. 5

5. Live colour brownish. Carapace ridges with scattered very long plumose setae......................... P. marina n. sp.

- Live colour orange. Carapace ridges without long plumose setae.................................... P. phanus n. sp.

6. Protogastric region armed with parahepatic spines.......................................... P. heptacanthus n. sp.

- Parahepatic spines on protogastric region absent............................................................. 7

7. Flexor margin of Mxp3 merus with 2–3 prominent spines..................................................... 8

- Flexor margin of Mxp3 merus with one prominent spine only................................................. 23

8. Epigastric region with 2 spines.............................................................. P. iphiclus n. sp.

- Epigastric region with 3–5 spines......................................................................... 9

9. Epigastric region with 3 spines.......................................................................... 10

- Epigastric region with 4–5 spines........................................................................ 11

10. Rostrum leaf-like, with minute or distinct pair of subapical spines, lateral margins convex. P2–4 propodi stout, 4–5 × as long as wide. Three anterior branchial spines........................................................ P. hylas n. sp.

- Rostrum triangular: without distinct pair of subapical spines, lateral margins straight. P2–4 propodi slender, 8–9 × as long as wide. Two anterior branchial spines.............................................................. P. idas n. sp.

11. Epigastric region with 4 spines.......................................................................... 12

- Epigastric region with 5 spines or with 4 spines and one median process or a scale with thick plumose setae............ 13

12. Rostrum triangular, margins slightly concave. Thoracic sternite 4 widely contiguous to sternite 3......... P. boucheti n. sp.

- Rostrum dagger-like, margins slightly convex. Thoracic sternite 4 narrowly contiguous to sternite 3...... P. maestratii n. sp.

13. Epigastric ridge with 4 spines and one median process or scale with thick plumose setae, rarely with 5 spines (see P. butes )... .................................................................................................. 14

- Epigastric ridge with 5 spines........................................................................... 15

14. Antennal article 2 armed distally with well-developed mesial and lateral spines.......................... P. butes n. sp.

- Antennal article 2 unarmed, at most with small distomesial spine or granule........................... P. cepheus n. sp.

15. Rostrum leaf-like (subapical spines always present, lateral margins convex). Anterior protogastric ridge medially interrupted, with one scale behind median epigastric spine.................................................... P. eneus n. sp.

- Rostrum triangular (subapical spines absent or, if present, obsolescent, lateral margins straight or slightly concave). Anterior protogastric ridge not interrupted medially, without scale behind median epigastric spine............................ 16

16. Anterior branchial margin with 2 spines.................................................................. 17

- Anterior branchial margin with 3 spines.................................................................. 18

17. Anterior mesogastric ridge scale-like; anterior metagastric ridge not medially interrupted.............. P. punctatus n. sp.

- Anterior mesogastric ridge not medially interrupted or with small medial gap; anterior metagastric ridge medially interrupted................................................................. P. kermadecensis Schnabel & Ahyong, 2019

18. Anterior margin of thoracic sternite 3 nearly transverse with median and lateral projections................................................................................................. P. bengalensis Tirmizi & Javed, 1980

- Anterior margin of thoracic sternite 3 moderately convex sometimes with feeble median excavation................... 19

19. Anterior metagastric ridge not interrupted. Antennule article 1 with 4 distal spines (double distolateral spine absent).................................................................................. P. ikedai ( Miyake & Baba, 1965)

- Anterior metagastric ridge scale-like. Antennule article 1 with 5 distal spines (double distolateral spine present)......... 20

20. Pleonal tergite 3 with anterior and posterior transverse ridges...................................... P. acastus n. sp.

- Pleonal tergite 3 without posterior transverse ridge.......................................................... 21

21. Anterior protogastric ridge usually medially interrupted........................... P. erebus Schnabel & Ahyong, 2019

- Anterior protogastric ridge always not medially interrupted................................................... 22

22. Anterior mesogastric ridge medially interrupted................................................... P. argus n. sp.

- Anterior mesogastric ridge not medially interrupted................................................ P. paula n. sp.

23. Epigastric ridge with 5 spines, with median spine........................................................... 24

- Epigastric ridge with 2–6 spines, without median spine...................................................... 25

24. Proximal half of extensor margin of P2–4 propodi armed with 1–4 well-developed spines. P2–4 propodi slender (6–7 × as long as wide)................................................................................. P. koumac n. sp.

- Extensor margin of P2–4 propodi unarmed, otherwise serrated. P2–4 propodi stout (4–5 × as long as wide). P. pulchrus n. sp.

25. Epigastric region typically with 4 spines, small specimens can have lateral pair much smaller (sometimes granular) than mesial pair............................................................................................... 26

- Epigastric region always with 2 spines................................................................... 33

26. Anterior branchial margin of carapace with 2 spines............................................... P. pollux n. sp.

- Anterior branchial margin of carapace with 3 spines......................................................... 27

27. Anterior margin of thoracic sternite 3 convex, without median projection. Anterior metagastric ridge medially interrupted. Pleonal tergite 3 usually without posterior transverse ridge.................................................... 28

- Anterior margin of thoracic sternite 3 biconcave, with obtuse median projection. Anterior metagastric ridge continuous, not medially interrupted. Pleonal tergite 3 with anterior and posterior transverse ridge................................. 31

28. Anterior mesogastric ridge medially interrupted.................................................. P. porteri n. sp.

- Anterior mesogastric ridge not medially interrupted......................................................... 29

29. Antennular lateral-most spine very small to indistinct. Antennal article 3 armed distally with well-developed mesial and lateral spines............................................................................ P. lenzi ( Rathbun, 1907)

- Antennular lateralmost spine always distinct. Antennal article 3 armed distally with small mesial spine only............ 30

30. Thoracic sternite 3 moderately produced anterolaterally............................................ P. poeas n. sp.

- Thoracic sternite 3 anterolateral margins with broad granule or square.................... P. pusillus ( Henderson, 1885)

31. Rostrum lateral margins straight................................................. P. nui Schnabel & Ahyong, 2019

- Rostrum lateral margins convex......................................................................... 32

32. Antennular lateralmost spine always distinct. Antennal article 2 armed with a well-developed lateral spine, reaching or overreaching article 3.................................................... P. australis Schnabel & Ahyong, 2019

- Antennular lateralmost spine very small to indistinct. Antennal article 2 unarmed, otherwise with a minute spine......................................................................................... P. integrus ( Benedict, 1902)

33. Anterior branchial margin with 2 spines.................................................................. 34

- Anterior branchial margin with 3 spines.................................................................. 42

34. Pleonal tergite 3 with anterior and posterior transverse ridge.............................. P. serrirostris ( Melin, 1939)

- Pleonal tergite 3 without posterior transverse ridge.......................................................... 35

35. Hepatic margin with small spine between anterolateral and first branchial spines.................................. 36

- Hepatic margin without small spine between anterolateral and first branchial spines................................ 37

36. Carapace with some scales between main ridges. Sternite 3 broad, more than 3 × as wide as long. Ocular peduncle narrower than cornea.............................................................................. P. peneleos n. sp.

- Carapace without scales between main ridges. Sternite 3 moderately broad, less than twice as wide as long. Ocular peduncle as wide as or wider than cornea............................................................... P. bahamut n. sp.

37. Anterior metagastric ridge not medially interrupted. Rostrum with subapical spines absent or obsolescent.............. 38

- Anterior metagastric ridge medially interrupted or scale-like. Rostrum with subapical spines......................... 39

38. Anterior margin of thoracic sternite 3 straight or slightly convex, produced anterolaterally. Antennal article 3 usually with distomesial spine. Live colour basis of carapace and pleon whitish with reddish patches................. P. barbeae n. sp.

- Anterior margin of thoracic sternite 3 medially projected or convex, anterolaterally rounded. Antennal article 3 unarmed. Base live colour of carapace and pleon green or light orange............................................. P. pepei n. sp.

39. Anterior metagastric ridge scale-like. Carapace ridges barely distinct with a few short setae.............. P. orpheus n. sp.

- Anterior metagastric ridge medially interrupted. Carapace ridges clearly distinct with dense short setae................. 40

40. Rostrum margin convex from the basis to the tip................................................. P. lynceus n. sp.

- Rostrum margin proximally straight (bottle-shaped)......................................................... 41

41. Carapace ridges with a few or without thick iridescent setae............................. P. integrirostris ( Dana, 1852)

- Carapace ridges always with thick iridescent setae............................................... P. priasus n. sp.

42. P2–4 dactyli without sharp upright cuticular spines (dactylar spines) at bases of movable spines..................... 43

- P2–4 dactyli with sharp upright cuticular spines (dactylar spines) at bases of movable spines........................ 50

43. Pleonal tergite 3 with anterior and posterior transverse ridges................................................. 44

- Pleonal tergite 3 without posterior transverse ridge.......................................................... 47

44. Subapical spines of rostrum well developed. Posterior transverse ridge of pleonal tergite 3 continuous................. 45

- Subapical spines of rostrum minute. Posterior transverse ridge of pleonal tergite 3 medially interrupted or scale-like...... 46

45. Anterior metagastric ridge medially not interrupted or interrupted; large median scale in metagastric area. Anterior margin of thoracic sternite 3 medially projected.......................................................... P. laureae n. sp.

- Anterior metagastric ridge usually scale-like; small median scale in metagastric area. Anterior margin of thoracic sternite 3 slightly convex........................................................................... P. gustavi n. sp.

46. Thoracic sternite 3 quadrangular (less than twice as long as broad). Scale between epigastric spines with thick setae................................................................................................ P. tiphys n. sp.

- Thoracic sternite 3 moderately broad (twice as long as broad). Scale between epigastric spines without thick setae.................................................................................................. P. zetes n. sp.

47. Rostrum without subapical spines or obsolescent. Anterior upper margin of pterygostomian flap usually serrated................................................................................................... P. medea n. sp.

- Rostrum with small subapical spines. Anterior upper margin of pterygostomian flap usually smooth................... 48

48. Antennal article 3 with distomesial and distolateral spines....................................... P. janiqueae n. sp.

- Antennal article 3 with distomesial spine only.............................................................. 49

49. Rostrum with well-developed subapical spines (tridentiform). Thoracic sternite 3 quadrangular (less than twice wider than long).................................................................................... P. talaus n. sp.

- Rostrum with minute subapical spines. Thoracic sternite 3 moderately broad (twice as wide as long).......................................................................................... P. triginta Schnabel & Ahyong, 2019

50. Pleonal tergites 2–4 with anterior and posterior ridges. Carapace always with secondary ridges. Rostrum dagger-like..... 51

- Pleonal tergite 4 with anterior ridges only. Carapace rarely with secondary ridges. Rostrum leaf-like.................. 54

51. Spines of antennal article 2 clearly different, distomesial minute. P1 very slender (P 1 male more than 3.5 × as long as carapace)............................................................... P. spinosus Schnabel & Ahyong, 2019

- Spines of antennal article 2 subequal. P1 moderately slender or stout (P 1 male about or less than 3.0 × as long as carapace) 52

52. Antennal article 3 usually armed with distinct distomesial spine. Carapace broader than long............ P. asclepius n. sp.

- Antennal article 3 unarmed or with small process. Carapace usually as long as broad or slightly longer than broad....... 53

53. Carapace and pleonal ridges and ocular peduncles with numerous thick iridescent setae. Rostrum margin straight................................................................................................ P. euryalus n. sp.

- Carapace and pleonal ridges and ocular peduncles with scattered thick iridescent setae. Rostrum margin nearly straight or slightly convex.............................................................................. P. lini n. sp.

54. Anterior metagastric ridge medially or laterally interrupted....................................... P. amphion n. sp.

- Anterior metagastric ridge not interrupted.................................................... P. joannotae n. sp.