Discoxenus

Kanao, Taisuke & Maruyama, Munetoshi, 2015, Eight new species, a new record, and redescription of the genus Discoxenus Wasmann, 1904: The first record of termitophilous rove beetles in Cambodia (Coleoptera: Staphylinidae: Aleocharinae), Zootaxa 4044 (2), pp. 201-223 : 204-205

Key to the Southeast Asian species of Discoxenus

1. Macrochaetotaxy of abdominal tergites III–VIII = 6, 6, 6, 6, 6, 6............................................... 2

- Macrochaetotaxy of abdominal tergites III–VIII variable...................................................... 7

2. Antennal segment XI approximately 1.4 times longer than wide ( Fig. 150 ); elytra sparsely covered with relatively long setae ( Fig. 156 ).................................................................................. D. katayamai

- Antennal segment IX more than 2 times longer than wide ( Figs. 55 , 74 , 90 , 106 , 122 , 138 ); elytra covered with no or few short setae except for anterolateral outer corner................................................................. 3

3. Abdominal sternites IV–VII with 2 rows of macrosetae....................................................... 4

- Abdominal sternites IV–VII with 1 row of macrosetae at posterior margin......................................... 5

4. Abdominal sternites IV–VII with 1 pair of macrosetae subapically................................. D. phourini n. sp.

- Abdominal sternites IV–VII with more than 5 pairs of macrosetae (10–11 macrosetae) subapically....... D. hirsutus n. sp.

5. Spermatheca with apical part longer than basal part ( Fig. 148 )..................................... D. kakizoei n. sp.

- Spermatheca with apical part shorter than basal part ( Figs. 88 , 120 )............................................. 6

6. Median lobe of male aedeagus with distal crest moderately pointed at apex ( Fig. 86 ); paramere with paramerite narrow ( Fig. 87 )............................................................................... D. kohkongensis n. sp.

- Median lobe of male aedeagus with distal crest rounded apically ( Fig. 118 ); paramere with paramerite broad ( Fig. 119 )............................................................................................ D. minutus n. sp.

7. Body long, length more than 2.3 mm ...................................................................... 8

- Body short, around 2 mm or less.......................................................................... 9

8. Pronotum sparsely covered with macrosetae ( Fig. 27 ); macrochaetotaxy of abdominal tergites III–VIII = 6, 6, 6, 6, 6, 4; median lobe of male aedeagus with basal capsule with distal crest weakly developed ( Fig. 35 )...... D. latiabdominalis n. sp.

- Pronotum with macrosetae only at lateral margin ( Fig. 127 ); macrochaetotaxy of abdominal tergites III–VIII = 4, 4, 4, 4, 4, 6; median lobe of male aedeagus with distal crest strongly developed ( Fig. 134 ).......................... D. lucidus n. sp.

9. Macrochaetotaxy of abdominal tergites III–V = 6, 6, 6...................................... D. cambodiensis n. sp.

- Macrochaetotaxy of abdominal tergites III–V = 8, 8, 8....................................................... 10

10. Macrochaetotaxy of abdominal tergites VI–V = 8, 8........................................... D. krishnai Kistner

- Macrochaetotaxy of abdominal tergites VI–V = 6, 6....................................... D. malaysiensis Kistner

Figures

FIGURES 149 – 164. Discoxenus katayamai: 149. Head, 150. Antenna, 151. Labrum (left side = dorsal view, right side = ventral view), 152. Mandible, left, 153. Mandible, right, 154. Mentum, 155. Pronotum, 156. Elytron, right, 157. Tergite VIII, 158. Sternite VIII, male, 159. Sternite VIII, female, 160. Tergites IX and X, 161. Median lobe of aedeagus, ventral view, 162. Median lobe of aedeagus, lateral view, 163. Paramere, 164. Spermatheca.

FIGURES 54 – 72. Discoxenus phourini n. sp.: 54. Head, 55. Antenna, 56. Labrum (left side = dorsal view, right side = ventral view), 57. Mandible, left, 58. Mandible, right, 59. Maxilla, 60. Mentum, 61. Labium, 62. Pronotum, 63. Elytron, right, 64. Meso- and metaventrites, 65. Tergite VIII, 66. Sternite VIII, male, 67. Sternite VIII, female, 68. Tergites IX and X, 69. Median lobe of aedeagus, ventral view, 70. Median lobe of aedeagus, lateral view, 71. Paramere, 72. Spermatheca.

FIGURES 73 – 88. Discoxenus kohkongensis n. sp.: 73. Head, 74. Antenna, 75. Labrum (left side = dorsal view, right side = ventral view), 76. Mandible, left, 77. Mandible, right, 78. Mentum, 79. Pronotum, 80. Elytron, right, 81. Tergite VIII, 82. Sternite VIII, male, 83. Sternite VIII, female. 84, Tergites IX and X. 85, Median lobe of aedeagus, ventral view, 86. Median lobe of aedeagus, lateral view, 87. Paramere. 88. Spermatheca.

FIGURES 89 – 104. Discoxenus hirsutus n. sp.: 89. Head, 90. Antenna, 91. Labrum (left side = dorsal view, right side = ventral view), 92. Mandible, left, 93. Mandible, right, 94. Mentum, 95. Pronotum, 96. Elytron, right, 97. Tergite VIII, 98. Sternite VIII, male, 99. Sternite VIII, female, 100. Tergites IX and X. 101. Median lobe of aedeagus, ventral view, 102. Median lobe of aedeagus, lateral view, 103. Paramere, 104. Spermatheca.

FIGURES 105 – 120. Discoxenus minutus n. sp.: 105. Head, 106. Antenna, 107. Labrum (left side = dorsal view, right side = ventral view), 108. Mandible, left, 109. Mandible, right, 110. Mentum, 111. Pronotum, 112. Elytron, right, 113. Tergite VIII, 114. Sternite VIII, male, 115. Sternite VIII, female, 116. Tergites IX and X, 117. Median lobe of aedeagus, ventral view, 118. Median lobe of aedeagus, lateral view, 119. Paramere, 120. Spermatheca.

FIGURES 121 – 136. Discoxenus lucidus n. sp.: 121. Head, 122. Antenna, 123. Labrum (left side = dorsal view, right side = ventral view), 124. Mandible, left, 125. Mandible, right, 126. Mentum, 127. Pronotum, 128. Elytron, right, 129. Tergite VIII, 130. Sternite VIII, male, 131. Sternite VIII, female, 132. Tergites IX and X, 133. Median lobe of aedeagus, ventral view, 134. Median lobe of aedeagus, lateral view, 135. Paramere, 136. Spermatheca.

FIGURES 137 – 148. Discoxenus kakizoei n. sp.: 137. Head, 138. Antenna, 139. Labrum (left side = dorsal view, right side = ventral view), 140. Mandible, left, 141. Mandible, right, 142. Mentum, 143. Pronotum, 144. Elytron, right, 145. Tergite VIII, 146. Sternite VIII, 147. Tergites IX and X, 148. Spermatheca.

FIGURES 19 – 37. Discoxenus latiabdominalis n. sp.: 19. Head, 20. Antenna, 21. Labrum (left side = dorsal view, right side = ventral view), 22. Mandible, left, 23. Mandible, right, 24. Maxilla, 25. Mentum, 26. Labium, 27. Pronotum, 28. Elytron, right, 29. Meso- and metaventrites, 30. Tergite VIII, 31. Sternite VIII, male, 32. Sternite VIII, female, 33. Tergites IX and X, 34. Median lobe of aedeagus, ventral view, 35. Median lobe of aedeagus, lateral view, 36. Paramere, 37. Spermatheca (ap: apical part, bp: basal part).