In this paper I have reported the morphological and biological observations on the larvae of seven species of wireworms belonging to the genus Melanotus ESCHSCHOLTZ, 1829.
The genus Melanotus is readily recognized by the ninth abdominal segment which is flattened at the tip, being usually more or less scalloped posteriorly.
Key to the Melanotus-larvae
1. Body yellowish brown. Second segment of maxillary palpi small, almost as long as wide. Ninth abdominal segment subconical; dorsum convex at anterior half, slightly sloping downward from front to back at posterior half. Median tooth (mto) weakly pointed and forming obtuseangled tip. Larvae not exceeding 25mm. in length.………2
1'. Body reddish brown. Second segment of maxillary palpi large at least 1.4 times as long as wide. Ninth abdominal segment subconical; dors um convex at anterior half, more or less gradually sloping downward from front to back at posterior half. Median tooth (mto) strongly pointed and forming an acute-angled tip. Larvae exceeding 30mm. in length.………3
2. Ninth abdominal segment subconical, about 1.7 times as long as wide; sides of anterior half slightly rounded, and posterior half tapering to a blunt tip. Tergite (tg) punctulate, punctures much denser in posterior half than in anterior half. ………M. fortnumi CANDÈE, 1878
2'. Ninth abdominal segment subconical, about 1.8 times as long as wide; sides of anterior half almost not rounded but straight, and posterior half weakly tapering to a blunt tip. Tergite (tg) uniformly punctulate, punctures a little denser in posterior half than in anteri orhalf. ………M. erythropygus CANDÈZE, 1873
3. Ninth abdominal segment moderately depressed and more or less flattened at posterior half. Median tooth (mto) a little longer than lateral teeth (lto), forming an angle of approximately 60° with lateral teeth (lto). ………4
3'. Ninth abdominal segment strongly depressed at posterior half. Median tooth (mto) about twice as long as lateral teeth (lto), forming an angle of approximately 40° with lateral teeth (lto). Larvae inhabiting in upland forest under bark of decayed coniferous trees.
………M. matsumurai SCHENKLING, 1927
4. Sides of ninth abdominal segment widest near base. Tergite (tg) moderately convex at anterior half, with surface almost uniformly punctulate, punctures less minute in anterior half than in posterior half. ………5
4'. Sides of ninth abdominal segment widest at middle. Tergite (tg) strongly convex at anterior half, with surface densely punctulate, punctures becoming much minuter in anterior half than in posterior half. ………M. legatus CANDÈZE, 1860
5. Lateral teeth (lto) of ninth abdominal segment broad, projecting laterad, forming regular triangle in fresh specimens, with prominent teeth (pto) forming a large nodule respectively.
………M. senilis CANDÈZE, 1865
5'. Lateral teeth (lto) of ninth abdominal segment narrow, sharply pointed towards posteriorly, with prominent teeth (pto) forming small fang-like tooth respectively. ………M. cete CANDÈZE, 1860