Key to species of the genus Galathea in the Indian and Pacific Oceans*
(*) Galathea paucilineata Benedict, 1902, from the Galápagos Islands, probably belongs to the genus Leiogalathea Baba, 1969 and is not included in the key.
1. Transverse ridges on carapace dorsal surface mostly obsolescent............................................... 2
– Transverse ridges on carapace dorsal surface distinct......................................................... 4
2. Mxp3 merus with flexor distal spine subequal to proximal spine........................ G. kuboi Miyake & Baba, 1967
– Mxp3 merus with flexor distal spine smaller than proximal spine............................................... 3
3. Epipod present on P1. Rostrum elongate, more than 1.5 times longer than broad. Gastric region with some scale-like ridges................................................................ G. nuda Macpherson & Robainas-Barcia, 2015
– Epipods absent on P1–3. Rostrum short, 1.5 times longer than broad or less so. Gastric region smooth, without scale-like ridges....................................................... G. setigera Macpherson & Robainas-Barcia, 2015
4. Anterolateral spine of carapace prominent, reaching tip of basal lateral tooth of rostrum. Posterior branchial margin with 6 spines............................................................................ G. vitiensis Dana, 1853
– Anterolateral spine of carapace never reaching tip of basal lateral tooth of rostrum. Posterior branchial margin with at most 5 spines.............................................................................................. 5
5. Pterygostomian flap with at least 1 spine on upper margin near linea anomurica.................................... 6
– Pterygostomian flap unarmed on upper margin (rarely with row of denticles)..................................... 11
6. Pterygostomian flap with row of spines on upper margin. Mxp3 merus more than twice ischium length............................................................................................. G. labidolepta Stimpson, 1858
– Pterygostomian flap with 1 or 2 spines on upper margin. Mxp3 merus as long as or slightly shorter than ischium length.... 7
7. Anterior mesogastric ridge of carapace interrupted.................... G. ahyongi Macpherson & Robainas-Barcia, 2015
– Anterior mesogastric ridge of carapace uninterrupted........................................................ 8
8. Mxp3 merus with strong median spine on flexor margin, exceeding distal margin of merus. Distal part of P1 palm without black spot........................................................... G. senta Macpherson & Robainas-Barcia, 2015
– Mxp3 merus with weak median spine on flexor margin, at most reaching distal margin of merus. Distal part of P1 palm with black spot........................................................................................... 9
9. P2 propodus 4 times longer than broad............................................... G. mauritiana Bouvier, 1914
– P2 propodus 3.0–3.5 times longer than broad............................................................... 10
10. P2–3 propodi each with 5 or 6 movable spines along flexor margin....... G. aequata Macpherson & Robainas-Barcia, 2015
– P2–3 propodi each with 4 movable spines along flexor margin.............. G. acis Macpherson & Robainas-Barcia, 2015
11. Uninterrupted mesogastric ridge between anteriormost branchial marginal spines.................................. 12
– Interrupted or scale like mesogastric ridge(s) between anteriormost branchial marginal spines....................... 27
12. Carapace with 2 epigastric spines....................................................................... 13
– Carapace without epigastric spines...................................................................... 23
13. Stiff plumose stiff setae present on carapace and rostrum.................................................... 14
– No stiff plumose setae on carapace and rostrum............................................................ 18
14. P2–3 propodi elongate, 5 times longer than broad..................... G. simulata Macpherson & Robainas-Barcia, 2015
– P2–3 propodi short, equal to or less than 4 times longer than broad............................................. 15
15. Gastric region with short posterior median protogastric ridge and short posterior median mesogastric ridge............................................................................................ G. aegyptiaca Paul’son, 1875
– Gastric region without short posterior median protogastric ridge and short posterior median mesogastric ridge (sometimes one these ridges can be present)............................................................................ 16
16. P2–3 meri 2.5 times longer than broad............................... G. imitata Macpherson & Robainas-Barcia, 2015
– P2–3 meri equal to or more than 3 times longer than broad................................................... 17
17. Ultimate article of antennular peduncle elongate, 2.5 times longer than broad Rostrum as long as broad............................................................................. G. corbariae Macpherson & Robainas-Barcia, 2015
– Ultimate article of antennular peduncle short, at most twice longer than broad. Rostrum longer than broad.......................................................................... G. homologa Macpherson & Robainas-Barcia, 2015
18. Epipods on P1–2 at least............................................................................... 19
– Epipods on P1 only................................................................................... 22
19. Pterygostomian flap unarmed on surface. Epipods on P1–2.................................. G. guttata Osawa, 2004
– Pterygostomian flap with facial spine on anterior part. Epipods on P1–3......................................... 20
20. Parahepatic spine absent. Carapace lateral margin without spine between anterolateral spine and anteriormost spine of branquial margin........................................................ G. rhanis Macpherson & Robainas-Barcia, 2015
– Parahepatic spine present. Carapace lateral margin with spine between anterolateral spine and anteriormost spine of branquial margin............................................................................................. 21
21. P2–4 meri slender; P2 merus 3.5–4.0 times as long as broad............ G. paulayi Macpherson & Robainas-Barcia, 2015
– P2–4 meri stout; P2 merus nearly 3.0 times as long as broad....................................... G. stilla sp. nov.
22. Mxp3 merus with flexor distal spine smaller than proximal spine. P2–4 propodi less than 5 times longer than broad.................................................................... G. boucheti Macpherson & Robainas-Barcia, 2015
– Mxp3 merus with flexor distal spine subequal to proximal spine. P2–4 propodi more than 5 times longer than broad.............................................................................. G. amamiensis Miyake & Baba, 1966
23. Scale-like stria present behind anterior protogastric ridge of carapace. External limit of orbit ending in small spine.................................................................................. G. continua Baba & Fujita, 2008
– No scale-like stria present behind anterior protogastric ridge of carapace. External limit of orbit ending in strong spine.... 24
24. Anterior branchial margin with 3 spines............................................. G. platycheles Miyake, 1953
– Anterior branchial margin with 2 spines.................................................................. 25
25. Carapace with 1 hepatic spine on each side............................ G. celiae Macpherson & Robainas-Barcia, 2015
– Carapace without hepatic spines........................................................................ 26
26. Rostrum with lateral teeth shallowly incised............................................. G. latirostris Dana, 1852
– Rostrum with lateral teeth deeply incised.......................................... G. spinimanus Borradaile, 1900
27. Rostrum with 2 lateral teeth............................................................................ 28
– Rostrum with more than 3 lateral teeth................................................................... 30
28. Rostrum with lateral teeth shallowly incised and located distally. Subdivision of telson complete..... G. bidens Baba, 1988
– Rostrum with lateral teeth spiniform and strong, located proximally. Subdivision of telson incomplete................ 29
29. Carapace dorsally with 2 epigastric, 4 protogastric, and 2 postcervical spines only. Pleonal tergites 2–4 with 2 transverse ridges. P2–4 spineless on lateral surface of meri, carpi and propodi.......................... G. quinquespinosa (Balss, 1913)
– Carapace dorsally with numerous spines other than 2 epigastric, 4 protogastric and 2 postcervical spines. Pleonal tergites 2–4 with 2 transverse ridges each followed by additional stria. P2–4 with spines on lateral surface of meri, carpi and propodi...................................................................................... G. lumaria Baba, 2005
30. Rostrum with 3 lateral teeth........................................................... G. patae Osawa, 2006
– Rostrum with 4 or 5 lateral teeth........................................................................ 31
31. Rostrum with 5 lateral teeth........................................................................... 32
– Rostrum with 4 lateral teeth........................................................................... 39
32. Epipods absent on P1–3................................................................ G. tropis Baba, 2005
– Epipods present only on P1............................................................................ 33
33. Two or more epigastric spines.......................................................................... 34
– Epigastric spines absent............................................................................... 38
34. Distoflexor angle of P2–4 meri with 2 spines.............................................................. 35
– Distoflexor angle of P2–4 meri with 1 spine............................................................... 36
35. Hepatic region with 2 or 3 spines. Carapace with numerous scale-like ridges on gastric region. Mxp3 merus with flexor distal spine smaller than proximal spine............................. G. multicristata Macpherson & Robainas-Barcia, 2015
– Hepatic region unarmed. Carapace with few scale-like ridges on gastric region. Mxp3 merus with flexor distal spine subequal to proximal spine............................................... G. ciliosa Macpherson & Robainas-Barcia, 2015
36. Posterior branchial region with 6–8 transverse ridges.................. G. inermis Macpherson & Robainas-Barcia, 2015
– Posterior branchial region with 4 or 5 transverse ridges....................................................... 37
37. Rostrum less than 1.5 times longer than broad. P2 merus less than 5 times longer than broad... G. sanctae Macpherson, 2012
– Rostrum more than 1.5 times longer than broad. P2 merus more than 5 times longer than broad..................................................................................... G. paulae Macpherson & Robainas-Barcia, 2015
38. Posterior branchial region behind mid-transverse ridge with 5 or 6 ridges. Gastric region with 4 or 5 uninterrupted or interrupted transverse ridges................................................................ G. sinensis Dong & Li, 2010
– Posterior branchial region behind mid-transverse ridge with 8 or 9 ridges. Gastric region with 9 or 10 uninterrupted or interrupted ridges......................................................................... G. multilineata Balss, 1913
39. Rostrum truncate.................................................................................... 40
– Rostrum triangular, not truncate......................................................................... 42
40. Epigastric spines absent............................................................ G. formosa De Man, 1902
– Epigastric spines present.............................................................................. 41
41. Ground color of body red............................................................. G. pilosa De Man, 1888
– Ground color of body blue.................................... G. polyphemus Macpherson & Robainas-Barcia, 2015
42. Carapace with cardiac spines........................................................................... 43
– Carapace without cardiac spines........................................................................ 49
43. Antennular basal article with 2 well-developed terminal spines, distomesial spine minute or obsolescent............... 44
– Antennular basal article with 3 well-developed terminal spines................................................ 48
44. Carapace unarmed on protogastric region.......................... G. samadiae Macpherson & Robainas-Barcia, 2015
– Carapace with 1 or 2 spines on protogastric region.......................................................... 45
45. Carapace with 1 median spine on protogastric ridge; 1 parahepatic spine on each side....... G. echinata Macpherson, 2012
– Carapace with 2 small median spines on protogastric ridge; 2 or 3 parahepatic spines on each side.................... 46
46. Metagastric region with 2 spines......................................................... G. robusta Baba, 1990
– Metagastric region unarmed............................................................................ 47
47. Cardiac region with 2 median spines. Posterior branchial area with one spine on each side, behind mid-transverse ridge......................................................................................... G. bicornis sp. nov.
– Cardiac region with 4–6 median spines. Posterior branchial area unarmed behind mid-transverse ridge............................................................................... G. sentosa Macpherson & Robainas-Barcia, 2015
48. Carapace with 1 strong median spine on protogastric ridge............................. G. profunda Macpherson, 2012
– Carapace with 2 small median spines on protogastric ridge........................... G. barbellata Macpherson, 2012
49. Gastric region with all ridges scale-like, usually arcuate (at most epigastric or protogastric ridges transverse with multiple interruptions)....................................................................................... 50
– Gastric region with some ridges not scale-like.............................................................. 75
50. Ocular peduncles elongate, more than 2.5 times longer than broad.... G. longioculata Macpherson & Robainas-Barcia, 2015
– Ocular peduncles short, clearly less than twice longer than broad............................................... 51
51. Branchial region of carapace with at least 1 dorsal spine..................................................... 52
– Branchial region of carapace without dorsal spines.......................................................... 63
52. Epigastric spines absent. Rostrum at least twice longer than wide.............................................. 53
– Epigastric spines present. Rostrum less than twice longer than wide............................................ 55
53. Rostrum twice longer than wide................................................. G. genkai Miyake & Baba, 1964
– Rostrum more than 2.5 times longer than broad............................................................. 54
54. P2 more than twice carapace length. P2 merus more than 6 times longer than broad.............................................................................................. G. gladiola Macpherson & Robainas-Barcia, 2015
– P2 less than twice carapace length. P2 merus less than 6 times longer than broad.............................................................................................. G. machaera Macpherson & Robainas-Barcia, 2015
55. P2–4 meri each with 2 spines at distoflexor angle (1 spine sometimes absent in small specimens)................................................................................... G. lepidota Macpherson & Robainas-Barcia, 2015
– P2–4 meri each with 1 spine at distoflexor angle............................................................ 56
56. Carapace with 1 postcervical spine on each side............................................................ 57
– Carapace without postcervical spines..................................................................... 58
57. Anterior branchial region unarmed. Epipods only on P1.................. G. cymo Macpherson & Robainas-Barcia, 2015
– Anterior branchial region with spines. Epipods on P1–3.............................. G. subsquamata Stimpson, 1858
58. Epipod only on P1................................................................................... 59
– Epipods on P1–3..................................................................................... 60
59. P1 fingers clearly longer than palm................................ G. acerata Macpherson & Robainas-Barcia, 2015
– P1 fingers clearly shorter than palm................................................. G. longimana Paul’son, 1875
60. Carapace lateral margin without spine between anterolateral spine and anteriormost spine of branchial margin........................................................................ G. polydora Macpherson & Robainas-Barcia, 2015
– Carapace lateral margin with spine between anterolateral spine and anteriormost spine of branchial margin............. 61
61. Distomesial spine of antennal article 1 nearly reaching end of peduncle. P2 merus 4.9–5.3 times as long as broad.................................................................................... G. johnsoni Lin & Osawa, 2016
– Distomesial spine of antennal article 1 slightly exceeding end of article 2. P2 merus 3.2–3.4 times as long as broad....... 62
62. Carapace as long as broad. Ridges on posterior half of carapace behind mid-transverse ridge usually laterally scale-like. Rostrum less than 1.5 times longer than broad. P2–4 propodi more than 4 times longer than broad........................................................................................... G. peitho Macpherson & Robainas-Barcia, 2015
– Carapace longer than broad. Ridges on posterior half of carapace usually laterally uninterrupted and never scale-like. Rostrum more than 1.5 times longer than broad. P2–4 propodi 4 times longer than broad................. G. aculeata Haswell, 1882
63. Epipods absent on P1–3............................................................................... 64
– Epipods at least on P1................................................................................. 66
64. Carapace with 2 epigastric spines....................................................... G. squamea Baba, 1979
– Carapace without epigastric spines...................................................................... 65
65. Carapace lateral margin with spine between anterolateral spine and anteriormost spine of branchial margin. Antennular article 1 with small distomesial spine......................................................... G. ryuguu Osawa, 2015
– Carapace lateral margin without spine between anterolateral spine and anteriormost spine of branchial margin. Antennular article 1 with well-developed distomesial spine............ G. lopisma Macpherson, Rodríguez-Flores & Machordom, 2023
66. Epigastric spines absent............................................................................... 67
– Epigastric spines present.............................................................................. 69
67. Body color white, with numerous large red spots. P1-4 with white and red bands........ G. chura Osawa & Higashiji, 2012
– Body color and pereiopods brown or orange............................................................... 68
68. Scale-like ridges on meta and mesogastric areas arcuate. P2–4 meri 2.5–2.7 times as long as broad. Short setae on dorsal carapace surface simple....................................... G. lemniscata Macpherson & Robainas-Barcia, 2015
– Scale-like ridges on meta and mesogastric areas transverse, not arcuate. P2–4 meri 4.0 times as long as broad. Short setae on dorsal carapace surface plumose............................................................ G. arani sp. nov.
69. Epipods on P1–2.............................................. G. poupini Macpherson & Robainas-Barcia, 2015
– Epipods only on P1................................................................................... 70
70. Carapace with all ridges between mid-transverse ridge and posterior ridge scale-like............................... 71
– Carapace with at least 2 medially uninterrupted ridges between mid-transverse ridge and posterior ridge............... 73
71. Carapace with 2 epigastric spines................................................. G. submagnifica Laurie, 1926
– Carapace with at least 4 epigastric spines................................................................. 72
72. Carapace without parahepatic spines................................ G. waiora Macpherson & Robainas-Barcia, 2015
– Carapace with 1 parahepatic spine on each side...................... G. furfurea Macpherson & Robainas-Barcia, 2015
73. P2–3 meri each with 2 spines at distoflexor angle....................................... G. magnifica Haswell, 1882
– P2–3 meri each with 1 spine at distoflexor angle............................................................ 74
74. Pterygostomian facial spine present............................... G. bracteosa Macpherson & Robainas-Barcia, 2015
– Pterygostomian facial spine absent............................. G. schnabelae Macpherson & Robainas-Barcia, 2015
75. Carapace with well-developed median mesogastric spine..................................................... 76
– Carapace without median mesogastric spine, at most minute spines............................................. 77
76. Epipods on P1...................................... G. acaena Macpherson, Rodríguez-Flores & Machordom, 2023
– Epipods absent on P1–3............................................................ G. babai Dong & Li, 2010
77. Antennular basal article with 2 well-developed terminal spines, distomesial spine minute or obsolescent, clearly not reaching midlength of distolateral spine.......................................................................... 78
– Antennular basal article with 3 well-developed terminal spines, distomesial spine always reaching or exceeding midlength of distolateral spine.................................................................................... 105
78. Sternite 4 clearly broader than sternite 5........................ G. hispidissima Macpherson & Robainas-Barcia, 2015
– Sternite 4 narrower than sternite 5....................................................................... 79
79. Rostrum extremely narrow, 2.5–3.5 times longer than broad.................................................. 80
– Rostrum relatively broad, 2.0 times longer than broad or less than so........................................... 85
80. Carapace with pair of epigastric spines only......................... G. ganindo Macpherson & Robainas-Barcia, 2015
– Carapace with 4 or more epigastric spines................................................................. 81
81. Hepatic spine absent............................................. G. perone Macpherson & Robainas-Barcia, 2015
– Hepatic spine present................................................................................. 82
82. Anterior protogastric ridge interrupted or scale-like................... G. scolopia Macpherson & Robainas-Barcia, 2015
– Anterior protogastric ridge uninterrupted.................................................................. 83
83. Pleonal tergites 2–3 with 2 uninterrupted ridges..................... G. rhaphidia Macpherson & Robainas-Barcia, 2015
– Pleonal tergites 2–3 with 4 uninterrupted or interrupted ridges................................................. 84
84. Rostrum with distalmost lateral teeth minute, clearly smaller than distal second teeth............................................................................................ G. tribulosa Macpherson & Robainas-Barcia, 2015
– Rostrum with distalmost lateral teeth well-developed, slightly smaller than distal second teeth................................................................................................... G. inconspicua Henderson, 1885
85. Carapace without or with 2 epigastric spines only.......................................................... 86
– Carapace with 4 or more epigastric spines and often with spinules on hepatic and branchial regions................... 96
86. Pterygostomian flap with facial spine on anterior part........................................................ 87
– Pterygostomian flap unarmed on surface.................................................................. 90
87. Epipods on P1–3..................................................................................... 88
– Epipods on P1 and rarely on P2......................................................................... 89
88. Parahepatic spine present. Rostrum triangular.......................... G. clarki Macpherson & Robainas-Barcia, 2015
– Parahepatic spine absent. Rostrum trapezoidal..................... G. rubrispina Macpherson & Robainas-Barcia, 2015
89. Carapace without epigastric and parahepatic spines........................................... G. dianthus sp. nov.
– Carapace with epigastric and parahepatic spines..................... G. cymothoe Macpherson & Robainas-Barcia, 2015
90. Epipods absent on P1–3............................................................................... 91
– Epipods present at least on P1.......................................................................... 93
91. Hepatic spine present.......................................... G. eucrante Macpherson & Robainas-Barcia, 2015
– Hepatic spine absent.................................................................................. 92
92. Carapace lateral margin with spine between anterolateral spine and anteriormost spine of branchial margin. Pleonal tergites 2–3 with 2 transverse ridges................................................................. G. pennata sp. nov.
– Carapace lateral margin without spine between anterolateral spine and anteriormost spine of branchial margin. Pleonal tergites 2–3 with 4 or 5 transverse ridges............................................. G. yamashitai Miyake & Baba, 1967
93. Carapace with 1 parahepatic spine on each side...................... G. barbata Macpherson & Robainas-Barcia, 2015
– Carapace without parahepatic spines..................................................................... 94
94. Mxp3 merus with flexor distal spine smaller than proximal spine. Rostrum triangular.............. G. hispida Baba, 2005
– Mxp3 merus with flexor distal spine subequal to proximal spine. Rostrum nearly truncate........................... 95
95. Rostrum 2.0 times longer than broad; lateral margins convex; lateral spines small and shallowly incised............................................................................. G. phalangis Macpherson & Robainas-Barcia, 2015
– Rostrum 1.5–1.7 times longer than broad; lateral margins straight; lateral spines sharp and deeply incised........................................................................... G. punctata Macpherson & Robainas-Barcia, 2015
96. Epipods absent on P1–3........................................... G. micra Macpherson & Robainas-Barcia, 2015
– Epipods present at least on P1........................................................................... 97
97. Rostral lateral teeth shallowly incised. P1 fingers distally ending in incurved teeth to cross each other when closed...... 98
– Rostral lateral teeth deeply incised. P1 fingers distally spooned................................................ 99
98. Anterior metagastric ridge continued laterally on anterior branchial ridges.................... G. albatrossae Baba, 1988
– Anterior metagastric ridge not continued laterally on anterior branchial ridges.................................................................................................. G. pauxilla Macpherson & Robainas-Barcia, 2015
99. P2 propodus more than 8 times longer than broad................... G. caesariata Macpherson & Robainas-Barcia, 2015
– P2 propodus less than 8 times longer than broad........................................................... 100
100. Carapace with some anterior branchial and postcervical spines............................................... 101
– Carapace without anterior branchial and postcervical spines (rarely 1–2 minute spines)............................ 102
101. Distomesial spine of antennular basal article very small but distinct...................... G. pubescens Stimpson, 1858
– Distomesial spine of antennular basal article obsolescent................ G. crinita Macpherson & Robainas-Barcia, 2015
102. Anterior protogastric ridge with median prominent convexity, with 2 minute spines and some thick long setae................................................................................................. G. gibbosa sp. nov.
– Anterior protogastric ridge without median prominent convexity, unarmed and without thick long setae............... 103
103. Distomesial spine of antennular article 1 distinct. Ridges on dorsal surface of carapace with dense short plumose setae................................................................ G. pascualae Macpherson & Robainas-Barcia, 2015
– Distomesial spine of antennular article 1 obsolescent....................................................... 104
104. Rostrum lanceolate.............................................. G. villosa Macpherson & Robainas-Barcia, 2015
– Rostrum narrowly triangular..................................... G. tagaloa Macpherson & Robainas-Barcia, 2015
105. Carapace without epigastric spines..................................................................... 106
– Carapace with epigastric spines........................................................................ 129
106. Epipods absent on P1–3.............................................................................. 107
– Epipods present at least on P1......................................................................... 114
107. Anterior metagastric ridge usually extending laterally to anterior branchial ridges............................................................................................... G. politula Macpherson & Robainas-Barcia, 2015
– Anterior metagastric ridge not extending laterally to anterior branchial ridges.................................... 108
108. Hepatic spine present................................................................... G. lenis Baba, 1969
– Hepatic spine absent................................................................................. 109
109. Carapace distinctly longer than broad......................................... G. omanensis Tirmizi & Javed, 1993
– Carapace slightly broader than long or nearly as long as broad................................................ 110
110. Scale-like ridge behind midpoint of anterior protogastric ridge. Rostrum 1.8–2.0 times as long as broad............... 111
– No scale-like ridge behind midpoint of anterior protogastric ridge. Rostrum 1.2 times as long as broad................ 113
111. Spines on flexor margin of Mxp3 merus subequal.................................. G. bengala Tirmizi & Javed, 1993
– Proximal spine on flexor margin of Mxp3 merus much longer than distal spine.................................. 112
112. Anterior protogastric ridge medially interrupted. Rostral lateral teeth shallowly incised......................................................................................... G. connudata Macpherson & Robainas-Barcia, 2015
– Anterior protogastric ridge medially uninterrupted. Rostral lateral teeth deeply incised........................................................................................... G. anoplos Macpherson & Robainas-Barcia, 2015
113. Branchial carapace margin with 5 spines................................... G. rubromaculata Miyake & Baba, 1967
– Branchial carapace margin with 4 spines......................... G. nicobarica Tiwari, Padate, Cubelio & Osawa, 2022
114. Epipods present only on P1........................................................................... 115
– Epipods present on P1–3............................................................................. 125
115. Carapace without hepatic spine........................................................................ 116
– Carapace with hepatic spine........................................................................... 118
116. Carapace lateral margin without spine between anterolateral spine and anteriormost spine of branchial margin; mesogastric ridge scale-like..................................................................................... 117
– Carapace lateral margin with spine between anterolateral spine and anteriormost spine of branchial margin; mesogastric ridge medially uninterrupted............................................ G. eione Macpherson & Robainas-Barcia, 2015
117. One median scale behind anterior protogastric ridge. Mxp3 merus with distal spine on extensor margin................................................................................ G. psylla Macpherson & Robainas-Barcia, 2015
– Median scale behind anterior protogastric ridge absent. Mxp3 merus without distal spine on extensor margin.................................................................................... G. bimaculata Miyake & Baba, 1966
118. Anterior metagastric ridge extending laterally to anterior branchial ridges...................................... 119
– Anterior metagastric ridge not extending laterally to anterior branchial ridges.................................... 121
119. Pleonal tergites 2–3 each with 4 transverse ridges...................................... G. ternatensis De Man, 1902
– Pleonal tergites 2–3 each with 2 transverse ridges.......................................................... 120
120. Rostrum 1.5–1.6 times as long as broad........................... G. melobosis Macpherson & Robainas-Barcia, 2015
– Rostrum as long as broad................................................................. G. aurata sp. nov.
121. P2 merus more than 4 times longer than broad. P2 propodus 5 or more times longer than broad.................................................................................... G. patriciae Macpherson & Robainas-Barcia, 2015
– P2 merus less than 4 times longer than broad. P2 propodus less than 5 times longer than broad...................... 122
122. Carapace lateral margin with spine between anterolateral spine and anteriormost spine of branchial margin............. 123
– Carapace lateral margin without small but distinct spine between anterolateral spine and anteriormost spine of branchial margin.................................................................... G. maculiabdominalis Baba, 1972
123. Carapace with 2 uninterrupted ridges behind mid-transverse ridge; anterior protogastric ridge usually medially uninterrupted.................................................................................................. 124
– Carapace with at most 1 uninterrupted ridge behind mid-transverse ridge of carapace (rarely more than one); anterior protogastric ridge usually medially interrupted................................................... G. providentia Laurie, 1926
124. Parahepatic spine on each side................................. G. boisselierae Macpherson & Robainas-Barcia, 2015
– Parahepatic spine absent................................... G. kalingasagara Tiwari, Padate, Cubelio & Osawa, 2024
125. Carapace without hepatic spine............................................. G. boninensis Miyake & Baba, 1965
– Carapace with hepatic spinule(s)....................................................................... 126
126. Anterior branchial margin with 3 spines................................................................. 127
– Anterior branchial margin with 2 spines................................................................. 128
127. Carapace with 4 uninterrupted ridges behind mid-transverse ridge; male with G1–2.......... G. amboinensis De Man, 1888
– Carapace with 2 uninterrupted ridges behind mid-transverse ridge; male with G2 only............... G. inflata Potts, 1915
128. P1 palm more than 3 times longer than broad. Crista dentata of Mxp3 ischium with 14–20 teeth................................................................................................. G. leptocheir Baba & Fujita, 2008
– P1 palm twice longer than broad. Crista dentata of Mxp3 ischium with 8 teeth.................................................................................................... G. rangi Macpherson & Robainas-Barcia, 2015
129. Double distomesial spine on antennular article 1.......................... G. calcifer Rodríguez-Flores & Giribet, 2024
– Distomesial spine on antennular article 1 simple.......................................................... 130
130. Carapace always with 4 or more epigastric spines.......................................................... 131
– Carapace with 2 epigastric spines only (but see G. spinosorostris)............................................. 132
131. Epipods present on P1–3. P2–4 meri each with 2 spines at distoflexor angle. G. hydrae Macpherson & Robainas-Barcia, 2015
– Epipods present on P1. P2–4 meri each with 1 spine at distoflexor angle... G. pubipes Macpherson & Robainas-Barcia, 2015
132. Rostrum as long as broad; lateral margins strongly convex (subparallel between basal first and second incisions)................................................................................... G. cymbulaerostris Tirmizi, 1966
– Rostrum at least 1.2 times longer than broad; lateral margins straight or slightly convex (breadth smaller between basal second incisions than between basal incisions).................................................................. 133
133. Epipods absent on P1–3.............................................................................. 134
– Epipods present at least on P1......................................................................... 151
134. P1 fingers not spooned distally, distally ending in incurved spines to cross each other when closed................................................................................................ G. longimanoides Johnson, 1970
– P1 fingers distally spooned............................................................................ 135
135. P2 merus more than 5 times longer than broad. Lateral rostral teeth shallowly incised........................................................................................... G. minutiae Macpherson & Robainas-Barcia, 2015
– P2 merus less than 5 times longer than broad. Lateral rostral teeth usually deeply incised........................... 136
136. Flexor margin of Mxp3 merus with proximal spine clearly stronger than distal spine.............................. 137
– Flexor margin of Mxp3 merus with subequal spines or proximal slightly longer than distal......................... 146
137. Hepatic spine present............................................... G. ceti Macpherson & Robainas-Barcia, 2015
– Hepatic spine absent................................................................................. 138
138. Parahepatic spine present............................................................................. 139
– Parahepatic spine absent.............................................................................. 141
139. Posterior branchial region with 6–8 ridges. Rostrum trapezoidal........................ G. balssi Miyake & Baba, 1964
– Posterior branchial region at most with 5 ridges. Rostrum triangular........................................... 140
140. Rostrum twice longer than broad. Flexor margin of Mxp3 merus with 3 spines................................................................................................... G. galene Macpherson & Robainas-Barcia, 2015
– Rostrum less than twice longer than broad. Flexor margin of Mxp3 merus with 2 spines.... G. raventosae Macpherson, 2012
141. Carapace without scale-like stria behind anterior protogastric ridge. Mxp3 merus with large flexor distal spine.......................................................................................... G. nasimae Karasawa, 2019
– Carapace with scale-like stria behind anterior protogastric ridge. Mxp3 merus with small flexor distal spine........... 142
142. Carapace with numerous long iridescent setae; posterior protogastric ridge divided into some scale-like ridges; median scale-like ridge with some long iridescent setae............................ G. paleroi Macpherson & Robainas-Barcia, 2015
– Carapace without or with a few long iridescent setae; posterior protogastric ridge with median scale-like ridge only, with or without 2 long setae................................................................................. 143
143. Pterygostomian flap largely visible in dorsal view............. G. quadrangularis Tiwari, Padate, Cubelio & Osawa, 2024
– Pterygostomian flap not visible in dorsal view............................................................ 144
144. P1 fingers longer than or as long as palm. Distomesial spine of antennal article 1 exceeding antennal article 3.......... 145
– P1 fingers shorter than palm. Distomesial spine of antennal article 1 at most reaching end of antennal article 3............................................................................................ G. anepipoda Baba, 1990
145. Lateral rostral teeth shallowly incised............................. G. bharata Tiwari, Padate, Cubelio & Osawa, 2024
– Lateral rostral teeth deeply incised................................... G. gruis Macpherson & Robainas-Barcia, 2015
146. Anterior protogastric ridge strongly convex medially. Mesogastric and metagastric ridges scale-like................................................................................ G. erythrina Macpherson & Robainas-Barcia, 2015
– Anterior protogastric ridge transverse or slightly convex medially. Mesogastric and metagastric ridges not scale-like.... 147
147. Mesogastric or/and metagastric ridges medially interrupted........... G. anouchkae Macpherson & Robainas-Barcia, 2015
– Mesogastric and metagastric ridges medially uninterrupted.................................................. 148
148. Carapace without scale-like median ridge behind protogastric ridge........ G. argus Macpherson & Robainas-Barcia, 2015
– Carapace with scale-like median ridge behind protogastric ridge.............................................. 149
149. Mxp3 merus with extensor margin unarmed....................... G. tirmiziae Tiwari, Padate, Cubelio & Osawa, 2022
– Mxp3 merus with small distal spine on extensor margin..................................................... 150
150. P2–4 propodi 3.5–4.0 times longer than broad. Base color light brown..................... G. consobrina De Man, 1902
– P2–4 propodi 4.5–4.8 times longer than broad. Base color green.......... G. tagaro Macpherson & Robainas-Barcia, 2015
151. Epipods present at least on P1–2....................................................................... 152
– Epipods present on P1 only........................................................................... 155
152. Epipods present on P1–2. Pterygostomian flap unarmed on surface............................................ 153
– Epipods present on P1–3. Pterygostomian flap with facial spine on anterior part.................................. 154
153. Mxp3 merus with distal spine on extensor margin. Distomesial spine of antennal article 1 reaching end of article 3..................................................................... G. parvula Macpherson & Robainas-Barcia, 2015
– Mxp3 merus without distal spine on extensor margin. Distomesial spine of antennal article 1 exceeding antennal peduncle.............................................................. G. lemaitrei Macpherson & Robainas-Barcia, 2015
154. Pleonal tergite 2 with 2–3 ridges behind anterior ridge............................... G. australiensis Stimpson, 1858
– Pleonal tergite 2 with 1 ridge behind anterior ridge.................... G. minima Macpherson & Robainas-Barcia, 2015
155. Pterygostomian flap with facial spine on anterior part....................................................... 156
– Pterygostomian flap unarmed on surface................................................................. 160
156. Carapace with scattered feathered setae and scale-like median stria behind protogastric ridge.................................................................................................. G. coralliophilus Baba & Oh, 1990
– Carapace without both scattered feathered setae and scale-like median stria behind protogastric ridge................. 157
157. Carapace with 1 parahepatic spine on each side..................... G. eupompe Macpherson & Robainas-Barcia, 2015
– Carapace without parahepatic spine..................................................................... 158
158. Pleonal tergite 2 with 2 transverse ridges................................................................. 159
– Pleonal tergite 2 with 4 transverse ridges............................................. G. corallicola Haswell, 1882
159. Carapace lateral margin without spine between anterolateral spine and anteriormost spine of branchial margin..................................................................................... G. ohshimai Miyake & Baba, 1967
– Carapace lateral margin with small but distinct spine between anterolateral spine and anteriormost spine of branchial margin.............................................................................. G. orientalis Stimpson, 1858
160. Carapace without hepatic and parahepatic spines.......................................................... 161
– Carapace with hepatic and/or parahepatic spines........................................................... 167
161. P2–4 meri each with 2 spines at distoflexor angle...................................... G. brevimana Paul’son, 1875
– P2–4 meri each with 1 spine at distsoflexor angle.......................................................... 162
162. Carapace lateral margin without spine between anterolateral spine and anteriormost spine of branchial margin.................................................................... G. machordomae Macpherson & Robainas-Barcia, 2015
– Carapace lateral margin with spine between anterolateral spine and anteriormost spine of branchial margin............ 163
163. Mxp3 merus with flexor distal spine clearly smaller than proximal spine.................... G. tanegashimae Baba, 1969
– Mxp3 merus with flexor distal spine subequal to or slightly larger than proximal spine............................ 164
164. Anterior branchial margin with 3 spines............................. G. eridani Macpherson & Robainas-Barcia, 2015
– Anterior branchial margin with 2 spines................................................................. 165
165. Rostral lateral teeth shallowly incised............................... G. mariae Macpherson & Robainas-Barcia, 2015
– Rostral lateral teeth deeply incised...................................................................... 166
166. Carapace with 4 uninterrupted ridges between mid-transverse ridge and posterior margin. Pleonal tergites 2–3 with several ridges behind anterior ridge............................................... G. whiteleggi Grant & McCulloch, 1906
– Carapace with 2 uninterrupted ridges between mid-transverse ridge and posterior margin. Pleonal tergites 2–3 without additional ridges behind anterior ridge......................................... G. atua Macpherson & Robainas-Barcia, 2015
167. Carapace with both hepatic and parahepatic spines on each side.............................................. 168
– Carapace with either 1 hepatic or 1 parahepatic spine on each side............................................ 173
168. Anterior protogastric ridge medially interrupted with median scale-ridge....................................... 169
– Anterior protogastric ridge uninterrupted (rarely interrupted in G. eulimene)..................................... 170
169. P2 merus 4 times longer than broad. P2 more than twice carapace length... G. leporis Macpherson & Robainas-Barcia, 2015
– P2 merus 3 times longer than broad. P2 twice carapace length or less than so. G. tongi Macpherson & Robainas-Barcia, 2015
170. P1 movable finger with row of strong spines on mesial margin. Posterior median margin of pleonal somite 6 usually convex.............................................................................. G. spinosorostris Dana, 1852
– P1 movable finger unarmed or with small proximal spines on mesial margin. Posterior median margin of pleonal somite 6 straight........................................................................................... 171
171. P1 palm without row of small spine on dorsal surface.................. G. cephyra Macpherson & Robainas-Barcia, 2015
– P1 palm with row of small spines on dorsal surface........................................................ 172
172. P2–4 propodi 3–4 times longer than broad................................................... G. algae Baba, 1969
– P2–4 propodi 5 times longer than broad............................ G. eulimene Macpherson & Robainas-Barcia, 2015
173. Mxp3 merus with flexor distal spine subequal to or slightly larger than proximal spine............................ 174
– Mxp3 merus with flexor distal spine clearly smaller than proximal spine........................................ 176
174. Carapace with parahepatic spine, without hepatic spine................. G. gnoma Macpherson & Robainas-Barcia, 2015
– Carapace without parahepatic spine, with hepatic spine..................................................... 175
175. Rostral lateral teeth shallowly incised.................................... G. denticulata Macpherson & Cleva, 2010
– Rostral lateral teeth deeply incised................................... G. ploto Macpherson & Robainas-Barcia, 2015
176. Carapace with 1 hepatic spine, but without parahepatic spine.............. G. halia Macpherson & Robainas-Barcia, 2015
– Carapace without hepatic spine, but with parahepatic spine.................................................. 177
177. Distomesial spine of antennal article 1 exceeding antennal peduncle. Antennal article 3 unarmed.................................................................................... G. autahi Macpherson & Robainas-Barcia, 2015
– Distomesial spine of antennal article 1 only reaching end of article 2. Antennal article 3 with distomesial spine....................................................................... G. lingadua Macpherson & Robainas-Barcia, 2015