Bioacoustics of Himaloaesalus satoi

Epipharynx ( Fig. 75 ). Phoba divided into an anterior section (namely protophoba) and lateral sections (namely chaetoparia). Protophoba distinct and consisting of many short, blunt and densely arranged pegs, which are greater in number than those of Syndesus cornutus (Fabricius) , and with about 9–10 sensory spots mostly in anterior portion, which are absent in Syndesus cornutus . Haptomerum well separated from protophoba, consisting of 4 sensory spots, but without setae or spine. Setae in chaetoparia nearly as many as pegs in protophoba. Haptolachus consisting of 3 nesia, the median one being more elongate and bearing very small granules, the lateral nesia bearing brushes of setae with the left one much smaller than the right one; all nesia without setae. Epitorma well sclerotized and sharp at tip. Pternotorma well developed and sharp at tip. Mandibles ( Figs. 81–86 ). The term, "incisor teeth" used by Lawrence (1981) is somewhat misleading as incisor teeth sometimes can be explained as apical teeth; thus the term "inner teeth" will be used in this paper referring to Lawrence's incisor teeth. Left mandible with 3 apical teeth at tip, 2 penetrating molae at basal half, a ventral process at base and several inner tubercles along the inner edge between apical teeth and molae; apical teeth with dorsal one shorter and ventral one longer; inner tubercles minute and paler in color, not forming clear teeth; distal mola much longer and wider, with a concave, broad and somewhat vertical distal edge; basal mola shorter and smaller, somewhat triangular; ventral process rather big and paler. Right mandible with 2 apical teeth at tip, 2 simple molae at base and several inner tubercles between apical teeth and molae; apical teeth with dorsal one shorter than ventral one; inner tubercles greater in number than those of left mandible; both basal and distal molae restricted to dorsal side, triangular and rather shorter; ventral process fully developed as in left mandible. Outer edge of both mandibles coarse and dentate, with very few setae. Mouthparts ( Figs. 79, 80 ). Stipes without stridulatory teeth. Galea and lacinia separate and fixed to stipes. Galea without membranous subdivision. Lacinia bidentate at apex, not tridentate. Maxillary palpus with 3 palpomeres excluding palpifer and with palpifer present. Prementum with straight anterior edge between insertions of palpi. Labial palpus with 2 palpomeres, rather straight and glabrous, without palpifer. Hypopharynx markedly asymmetrical with right dorsally pointed sclerotized projection. Prothorax ( Fig. 78 ). Pronotum without an anteriorly projecting lobe or an extensive pronotal plate. Precoxale and episternum well sclerotized. Mesocoxal stridulatory organ (pars stridens, Figs. 70, 73 ). Pars stridens on posterior surface of mesocoxa being of Lawrence's type one: field of confused, rounded granules, all about equal in size. Metatrochanteral stridulatory organ (plectrum, Figs. 71, 74 ). Plectrum on anterior surface of metatrochanter consisting of at least 16 tight rows of granules; neighboring rows being spaced by a distance equal to the width of row; neighboring granules in the same row touched one another; granules oblong and a little rounded, smaller in terminal rows than in central rows. Tarsungulus . Tarsungulus of prothoracic leg ( Fig. 69 ) 2x longer and more gradually attenuated at apex than that of mesothoracic ( Fig. 70 ) and metathoracic legs ( Fig. 71 ), flanked by 2 shorter setae arising from the same position on each side. Tarsungulus of mesothoracic and metathoracic legs strongly and abruptly attenuated at apex, forming a short median tooth, flanked by 2 longer setae arising from the same position on each side. Vestiture of thoracic and abdominal tergites ( Figs. 62, 64 ). Spinules absent from prothoracic and mesothoracic tergites, very few on metathoracic tergite, fully developed on abdominal tergites 1–7, and absent from abdominal tergites 8–10. Vestiture of abdominal sternite 10 ( Fig. 66 ). Raster absent. Only a transversal row of sparse and long setae appeared near posterior margin. Anal sclerite . Anal sclerite ( Fig. 65 ) consisting of 3 lobes surrounding the anal opening and set off from the remainder of segment 10: a dorsal lobe and two lateral lobes. Abdominal sternite 10 about 1.5 times as long as tergite 10, causing anal sclerite somewhat oblique: dorsal lobe a little shorter than lateral lobes. All 3 lobes glabrous, with apparent oval pad. After the study of the larvae of Aesalus zhejiangensis , we have some doubts about the Emden (1935 , 1951 ) and Lawrence (1981) works concerning the presence of several inner tubercles on left mandible. In their works the number of inner teeth on the left mandible was used as a major character in larval classification, and a major split is based on the presence of at least one tooth along the inner edge of the left mandible between the two or three apical teeth and the mola, with the larvae possessing such inner teeth belonging to the subfamily Lucaninae ( sensu Holloway 1968 ) whilst the group lacking inner teeth includes Aesalus , Sinodendron , Ceruchus , Nicagus , Syndesus , Ceratognathus , and the subfamily Lampriminae . However, Aesalus zhejiangensis shows several small inner tubercles between apical teeth and mola, which cannot be easily distinguished from the inner teeth found in those Lucaninae species, such as Dorcus parallelipedus (Linnaeus) . Therefore we believe that the presence or absence of inner teeth cannot be used as a major character in classification of larval Lucanidae . Anyway, for a better larval classification more species need to be examined.