Coelotrachelus, Schmidt, 1913

Dellacasa, Marco, Dellacasa, Giovanni & Gordon, Robert D., 2009, Systematic revision of the genus Coelotrachelus Schmidt, 1913 (Scarabaeoidea: Scarabaeidae: Aphodiinae), Insecta Mundi 2009 (86), pp. 1-13 : 2

Key to species of Coelotrachelus

1. Elytron with shoulder denticulate ............................................................................................... 2

— Elytron with shoulder not denticulate ......................................................................................... 4

2(1). Disc of pronotum evenly finely punctured, punctures one size; sides narrowly flattened and with few large punctures. Chestnut-brown. Length 6.5-7.5 mm. Mexico ( México) ............................ .......................................................................................... C. ixtapalapaensis , new species

— Disc of pronotum dually punctured, small and large; large punctures irregularly scattered ..... 3

3(2). Lateral margins of pronotum almost straight, slightly inwardly sinuate before hind angles; large pronotal punctures relatively denser and coarser. Dark reddish to light brown. Length 6.0-7.0 mm. Mexico (Durango, Sinaloa) ..................................... C. symbius (Gordon and Howden)

— Lateral margins of pronotum regularly arcuate; large pronotal punctures relatively less dense and less coarse. Chestnut-brown. Length 6.0- 7.5 mm. U.S.A. (Arizona, Colorado, New Mexico) ; Mexico (Chihuahua, Durango) ................................................................. C. rudis (LeConte)

4(1). Pronotum with basal width one third of the medial width. Moderately shiny, reddish-brown. Length 8.0 mm. Mexico...................................................................... C. venustus (Schmidt)

— Pronotum with basal width one half of the medial width ........................................................... 5

5(4). Pronotum broadly transverse, moderately convex, with sides widely flattened and broadly bordered. Male fore tibiae relatively stout ( Fig. 16 ). Shiny, black. Length 7.0- 8.5 mm. Mexico (Durango, México, Veracruz) ............................................................................... C. kuntzeni (Schmidt)

— Pronotum moderately transverse, convex; sides rather narrowly flattened and narrowly bordered. Male fore tibiae relatively slender ( Fig. 5 ). Moderately shiny, chestnut brown. Length 6.0 mm. Mexico (Morelos) ............................................................. C. burgosi (Deloya and McCarty)

Figures

Figures 12-17. Coelotrachelus kuntzeni (Schmidt, 1913), holotype. 12) Habitus (morphological details). 13-14) Aedeagus (dorsal and lateral view). 15) Habitus. 16) Left fore tibia of male (dorsal view). 17) Epipharynx.

Figures 1-6. Coelotrachelus burgosi (Deloya and McCarty, 1992), [Apancingo de Michapa, m 1300, Morelos, Mexico, holotype. 1) Habitus (morphological details). 2-3) Aedeagus (dorsal and lateral view). 4) Habitus. 5) Left fore tibia of male (dorsal view). 6) Epipharynx.