Mimaenictus matsumotoi Maruyama

Maruyama, Munetoshi, Matsumoto, Takashi & Itioka, Takao, 2011, Rove beetles (Coleoptera: Staphylinidae) associated with Aenictus laeviceps (Hymenoptera: Formicidae) in Sarawak, Malaysia: Strict host specificity, and first myrmecoid Aleocharini, Zootaxa 3102, pp. 1-26 : 15

Mimaenictus matsumotoi Maruyama , sp. nov.

( Figs. 48–59 )

Holotype, 3 “ MALAYSIA: Sarawak, Lambir Hills National Park, 29 X 2004 / ATTM 574 / HOLOTYPE Mimaenictus matsumotoi Maruyama ” (no. 574). Paratypes: 3, same data as holotype but 20 IV 2004 (no. 313); 1, ditto, 13 IV 2004 (no. 340); 1, ditto, 16 IV 2004 (no. 348); 2, ditto, 12 V 2004 (no. 368); 2, ditto, 7 X 2004 (no. 413); 3, ditto, 10 X 2004 (no. 422); 1, ditto, 19 V 2004 (no. 428); 1, ditto, 4 XI 2004 (no. 517); 1, ditto, 21 X 2004 (no. 534); 1, ditto, 30 X 2004 (no. 542); 4, ditto, 29 X 2004 (no. 574); 1, ditto, 20 X 2004 (no. 555); 3, ditto, 21 X 2004 (no. 587); 14, ditto, 20 IV 2005 (no. 701); 10, ditto, 9 XI 2005 (no. 801); 1, ditto, 9 XI 2005 (no. 802); 2, ditto, 9 XI 2005 (no. 803); 6, ditto, 10 XI 2005 (no. 804). See, Table 1 for detailed collecting data.

Symbiotic host. Morphotype L1 of Aenictus laeviceps .

Distribution. Malaysia (Borneo).

Etymology. Dedicated to Dr. T. Matsumoto, the second author of this paper and collector of the type series.

Description. Almost uniformly reddish brown. Head ( Figs. 48–51 ) with dorsal surface completely glabrous except for several setae in front of eyes. Pronotum ( Fig. 52 ) with ratio length/width=1.24–1.25, with 7 or 8 setae along midline, 1 seta antero-laterally and 1 seta postero-laterally. Elytra with 6–10 minute setae. Abdomen ( Figs. 53–55 ) with numbers of macrosetae from tergite II–VIII: 1, 1, 1, 6, 6, 6; gland openings on sternites III–V clear. Male: median lobe of aedeagus ( Figs. 57, 58 ) gently narrowed apically in lateral view, with lateral ridge which is gradually narrowed from middle to apex in parameral view. Female: spermatheca ( Fig. 59 ) with basal part lacking basal projection; apical lobe with lateral ridge small.

Measurements. BL, ≈ 3.5–3.8; FBL, ≈ 1.7–1.9; HW, 0.53–0.56; EL, 0.254–0.263; AL, ≈ 1.7–1.8; PL, 0.56– 0.58; PW, 0.45–0.46; ELW, 0.67–0.69; HTL, 1.10–1.21. N=5.

Diagnosis. This species is most similar to Mimaenictus wilsoni (M. w.) in the presence of lateral ridge in median lobe of aedeagus, but is clearly distinguished from it by the shorter setae on the pronotum (in M. w., the setae are longer and denser in the anterior area and lap over each other) and the sparser setae on the elytra (M. w. has more than 15 setae). The shape of the median lobe of aedeagus and that of the spermatheca are also different. In M. w. the apical lobe of the median lobe of aedeagus ( Figs. 60, 61 ) is slightly constricted near the base and almost parallel-sided in lateral view, and the lateral ridge is almost semi-circular in parameral view; the basal part of spermatheca ( Fig. 62 ) is with a basal projection, and the apical lobe is with a large lateral ridge.

Figures

FIGURES 48 – 56. Mimaenictus matsumotoi sp. nov. (50 – 56, SEM photographs). 48, Habitus, dorsal view; 49, ditto, lateral view; 50, head, pronotum and anterior part of elytra, lateral view; 51, head, dorsal view; 52, pronotum, dorsal view; 53, abdominal tergites III – VI, dorsal view; 54, abdomen, lateral view; 55, abdominal sternite III – VI, ventral view; 56, gland opening on abdominal sternite IV, ventral view.

FIGURES 57 – 62. Mimaenictus spp.: 57 – 59, M. matsumotoi sp. nov.; 60 – 62, M. wilsoni (57, 60, median lobe of aedeagus, lateral view; 58, 61, ditto, ventral view; 59, 62, spermatheca. 57, 58, holotype).