THE ENITHARES (Hemiptera-Heteroptera: Notonectidae) OF THE ...

362 Pacific Insects Vol. 10, no. 2
ly transversely ridged biimpressa (Uhler)
Lateral margins of ventral Connexival segments not as above 42
42(41). More than 10 mm long metallica Brooks
Less than 9.5 mm long 43
43(42). Head width slightly more than 3X anterior width of vertex 44
Head width less than 3X anterior width of vertex 45
44(43). Inner surface of mid-tibia with a large nodule distally (fig. 264) ... thienemanni Lundblad
Inner surface of mid-tibia distally without a large nodule (fig. 271) atra Brooks
45 (43). Mid-tibia with many marginal spines (fig. 211}. Posterior lobe more or less upright
(fig. 280) amboinensis n. sp.
Mid-tibia with few marginal spines (fig. 174). Posterior lobe apically inclined
caudad (fig. 116) ripleyana n. sp.
46(38). More than 11.5 mm long 47
Less than 10.5 mm long 48
47(46). Posterior lobe apically finger-like set with spines, parameres short and rounded
(fig. 332) horvathi Kirkaldy
Posterior lobe broad and rounded, not set with spines apically, parameres very long
(fig. 285) stylata n. sp.
48(46). Mesotrochanter forming a distinct spur at inner ventral margin 49
Mesotrochanter rounded or angulate 52
49(48). Mid-femoral hairs very long, dorsal margin set with 5-6 stout spines (fig. 102) 50
Mid-femoral hairs short, dorsal margin not set with stout spines (fig. 288) 51
50(49). Outer lobe of mid-tibia distally rounded (fig. 103) alexis alexis Lansbury
Outer lobe of mid-tibia distally acuminate (fig. 110) alexis lairdi n. subsp.
51 (49). Fore tibia curved forward (fig. 293). Mid tibia distally swollen forming a convex
arch (fig. 289) malayensis Brooks.
Fore tibia not curved forward. Mid tibia not distally swollen (fig. 295) ... maai n. sp.
52 (48). Lateral margins of 1st 2 visible ventral abdominal segments with a series of transverse
ridges (fig. 147) nigra n. sp.
Lateral margins of 1st 2 visible ventral abdominal segments not as above 53
53(52). Lateral margins of pronotal fovea produced towards eyes as a spur or nodule 54
Lateral margins of pronotal fovea not as above 55
54 (53). Dorsal margin of pronotal fovea directed caudad behind eyes (fig. 307). Apex of
posterior lobe inclined caudad (fig. 305) foveatus n. sp.
Dorsal margin of pronotal fovea directed laterad behind eyes (fig. 157). Apex of
posterior lobe not inclined caudad (fig. 158) woodwardi n. sp.
55(53). Head width not more than 2.5X median head length 56
Head width over 2.5X median head length 61
56 (55). Dorsal margin of pronotal fovea directed laterad from behind eyes (fig. 149). Lateral
margins of metaxyphus more or less straight (fig. 150) bergrothi Montandon
Dorsal margin of pronotal fovea directed caudad from behind eyes. Lateral margins
of metaxyphus not straight, usually shallowly concave distally 57
57 (56). Parameres very long (fig. 336). First mid-tarsus with 4 stout spines set close together
medianly (fig. 335) freyi quadrispinosus Lansbury
Parameres very short. First mid-tarsus with a variable number of spines; not set
close together but dispersed along lateral margins 58
58(57). Head width more than 3X anterior width of vertex 59
Head width less than 3X anterior width of vertex 60
59 (58). Inner surface of mid-tibia with chaetotaxy interrupted distally (fig. 322); midtibia
distally concave (fig. 324). First mid-tarsus with 4 stout spines (fig. 323).