Table 2. Comparison of morphological features of Aquatica Fu et al., 2010 and Nipponoluciola gen. nov.
Aquatica Fu et al., 2010 (Fig. 4A‒D) Nipponoluciola gen. nov.
Recorded from China, Korea and Russia with one species from Japan Recorded only from Japan
Elytra black, may have fine paler margins, or elytra yellow Elytra black
Pronotal width slightly less than humeral width Pronotal width subequal to humeral width
Pronotal lateral margins divergent along length or subparallel-sided in posterior half Pronotal lateral margins slightly divergent along length
Elytra with no well defined interstitial lines Elytra with at least two well defined interstitial lines
Base of epipleuron wide Base of epipleuron narrow
Humerus narrowly visible or not visible from beneath Humerus widely visible from beneath
Epipleuron visible at elytral margins level with or anterior to posterior margin of MS Epipleuron visible at elytral margins well behind posterior margin of MS
Male V 7 without angulate corners V 7 with angulate corners
Male LO retracted to anterior half of V 7 LO occupies most of V 7
Aedeagal BP without median notch Aedeagal BP usually with median notch
ML of aedeagus with apical area much narrower than rest ML of aedeagus with apical area not much narrower than rest
Lateral margins of posterior area of aedeagal sheath sternite with toothed projections Lateral margins of posterior area of aedeagal sheath sternite without toothed projections
Posterior area of aedeagal sheath sternite about as wide as anterior area except for A. lateralis Posterior area of aedeagal sheath sternite much narrower than anterior area
Female with thin apically acute bursa plates Female no bursa plates
Female MO plate elongated may project into vagina Female MO plate short, not much wider than long, not projecting into vagina