Acrossus superatratus (Nomura et Nakane, 1951)

Shabalin, S. A., 2018, Description of the larva of Acrossus superatratus (Nomura et Nakane, 1951) (Coleoptera: Scarabaeidae) from the Russian Far East, Far Eastern Entomologist 352, pp. 9-13 : 10-12

Acrossus superatratus (Nomura et Nakane, 1951)

Figs 1–9

Aphodius (Acrossus) superatratus Nomura & Nakane, 1951: 36 . Type locality: "Buhei-toge,

Ise, Honshu" [ Japan, Honshu].

Aphodius (Acrossus) superatratus: Balthasar, 1964: 129 ; Nakane & Masumoto, 1967: 36;

Stebnicka, 1980: 233; Kim, 1987: 193; Dellacasa & Dellacasa, 2006b: 107; Gusakov,

2009: 128; Kim, 2012: 118; Akhmetova & Frolov, 2014: 406; Bezborodov, 2013: 131.

Acrossus superatratus: Dellacasa et al., 2016a: 2 ; Dellacasa et al., 2016b: 101.

Aphodius (Acrossus) arsenjevi Berlov, 1989: 394 . Type locality: Vladivostok [ Russia: Primorskii krai]. Synonymized by Stebnicka & Galante, 1991: 727.

Aphodius (Acrossus) arsenjevi: Bezborodov & Berlov, 2005: 325 .

MATERIAL. Russia: Primorskii krai. Four third-instar larvae, one second-instar larva,

and one first-instar larva reared from the eggs laid by the beetles collected in cow dung 21. V

2017 in Kaimanovka village and 24. V 2017 in Ryazanovka village by S.A. Shabalin .

DESCRIPTION. Larva of typical C-shape form. Head surface shiny, reddish-brown.

Medial part of pleural sclerites and base of frons a bit darker than remaining part of the head capsule. Head width of third-instar larva 2.10– 2.05 mm, length (without clypeus and labrum)

1.50 mm. Head width of second-instar larva 1.80 mm, length 1.20 mm. Head width of firstinstar larva 1.20, length 0.90 mm. Frontal sutures visible as fine lines. Length of epicranial suture approximately half height of frons. Each pleural sclerite with darkish spot in central part of epicranial suture; with 7 setae: 4 dorsoepicranial setae, 3 basiantenal setae. Frons with pair elongated depression in central part; with 4 rounded depressions above the fronto-

clypeal suture; with pair exterior frontal setae, and pair of setae of anterior frontal angle.

Ocelli absent. Clypeus trapezoidal, with pair of long setae laterally, with pair of shorten setae medially. Basal part of clypeus (2/3 length of clypeus) is darker than apical quarter. Labrum three-lobed, with 2 posterior setae; 2 central setae; and 4 lateral setae ( Fig. 1 ). Corypha with

4 marginal setae. Right and left clithrum being present, it surface thinly sclerotized. Epizygum and zygum absent. Haptomerum with 6 rounded sencillae. Plegmatium and proplegmatium absent. Right acantoparia with 6 marginal setae. Left acantoparia with 4 setae. Phoba in laterals parts with 1 setae row, in apical part with 2 setae row. Pedium rounded, it occupying between one-forth epipharengial surface. Epitorma narrow, long; its apical part rounded.

Dexiotorma and pternotorma almost straight. Haptolachus complete, but crepis absent. Nesium being present, it surface thinly sclerotized ( Fig. 2 ). Mandibles triangular, asymmetrical. Left mandible slightly longer than right one, its scissorial part wider. Base of mandibles light brown, scissorial and molar part almost black. Right mandible with 1 apical, acute scissorial tooth followed by 1 wide, scissorial blade. Without stridulatory area. Molar area complex of right mandibula, bilobed, with apical depression, basal molar lobe wide, dorso-longitudinally compressed ( Figs 5, 6 ). Left mandible with 1 apical, acute scissorial tooth and 2 wide scissorial blade. Without stridulatory area. Molar area complex of left mandibula, bilobed, apical molar lobe with subtriangular shortern teeth, basal molar lobe wide, dorso-longitudinally compressed. A well developed brush of bristles at base of both right and left molar parts

( Figs 3, 4 ). Maxillae symmetrical. Ventral side of stipes with one long basal and three short distal setae, dorsal side with row of 5 conical stridulatory teeth and three short setae near base of palpifer. Maxillary palp 4-segmented. Palpifer without stridulatory teeth, with 1 short seta ventrally. Ventral side of galea with longitudinal row of short setae. Dorsal side of galea mandible (dorsal view); 4 – left mandible (lateral view); 5 – right mandible (dorsal view); 6 –

right mandible (lateral view).

with 5 long setae; with small apical teeth. Dorsal side of lacinia with 8 long thick setae,

ventral side with 1 long thick seta basally. Apex of lacinia 4-dentate ( Figs 7, 8 ). Legs subequal in length, fore leg slightly shorter than others. Central part of anal sternite with 2 rows of relatively long, heavily sclerotized pali (11 in the row), laciniate apically. Rows removed caudally and becoming closer to each other basally. Anal sternite also with smaller 12–15

setae at each side of medial rows ( Fig. 9 ).

NOTES. As well as all other species of the genus Acrossus , larva of A. superatratus have two distinct rows of pali on anal sternite differing from lateral setae, and modified setae on central abdominal tergites, situated on conical tubercles.

DISTRIBUTION. Russia (Primorskii krai, Khabarovskii krai, Jewish autonomous region, Amurskaya oblast), North Korea (Hamgyengbuk-do, Yanggang-do), South Korea

(Gangwon-do, Jeju-do), Japan (Honshu).

view); 9 – raster.

Figures

Figs 1–6. Larva of Acrossus superatratus. 1 – head capsula, 2 – epipharynx, 3 – left

Figs 7–9. Larva of Acrossus superatratus. 7 – maxilla (dorsal view); 8 – maxilla (lateral