Mizotrechus grossus, Erwin, 2011

Erwin, Terry L., 2011, Rainforest understory beetles of the Neotropics, Mizotrechus Bates 1872, a generic synopsis with descriptions of new species from Central America and northern South America (Coleoptera, Carabidae, Perigonini), ZooKeys 145, pp. 79-128 : 94-96

Gross trough beetle Mizotrechus grossus sp. n. Figs 11 32 40 Plate 12

Holotype.

GUYANE, Saut Pararé, Arataie River, Nouragues Field Station, 51 m, 4.0378°N, 52.6725°W, 27 March 2010 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP126301, male).

Derivation of specific epithet

. The epithet “grossus” is a Latin adjective that adequately describes this species with large robust adults.

Proposed English vernacular name.

Gross trough beetle.

Diagnosis.

With the attributes of the genus as described above and very large sized for the genus as it is presently understood; adults have dark castaneous integument, except anterior parts of mandible, baso-lateral corner of labrum, and clypeal suture piceous. Frons shallowly rugose at sides and overall punctulate. Occiput punctulate. Pronotum cordiform with lateral margins straight to well-developed hind angle which is dentate; base densely microrugose. Elytra broad and short, moderately wider than the width of pronotum across anterior third, and with 3 well- impressed interneurs, outer interneurs more shallow toward margin; margins behind humeri uneven, but not evidently serrulate. Foreleg femur dentate on postero-ventral margin near base.

Description.

( Figs 11 , 32 , Plate 12 ). Size: See Appendix 1. Large for genus, ABL = 8.1-8.9 mm, SBL = 7.07-7.71 mm, TW = 2.72-3.26 mm. Color: see diagnosis, above. Luster: Head, pronotum and legs shiny; elytron shiny but with evident shallow and slightly stretched microsculpture. Head: Labrum quadrate and medially emarginate. Eye moderately large, moderately convex. Gena moderately long, straight. Frons, occiput, and gena glabrous. Prothorax: Broadly cordiform, narrowed moderately toward base, margin narrowly explanate, more broadly near base, hind angle dentate; surface punctulate, punctures widespread, glabrous, microsculpture nearly effaced. Pterothorax: Elytron moderately convex, intervals flat, interneurs striate, not punctate, apex oblique and straight, sutural apex narrowly rounded. Metasternum sparsely setiferous in male. Legs: Normal in both sexes; foreleg femur (as in Fig. 20 ) markedly dentate on postero-ventral margin at basal third; trochanter acute in both sexes, about half the length of the femur. Abdomen: Abdominal sterna moderately setiferous; sternum IV of male with narrow and dense patch of decumbent setae. Defense gland system ( Plate 12 ) with two very large, medially slightly concave, bean-shaped pygidial gland reservoirs, each with a markedly long and narrow annulated collecting canal connected to the efferent duct near the base of the gland. Male genitalia: Median lobe ( Fig. 32 ) elongate and robust with ostium moderately elongate, over half the length of the median lobe; apex with a losp. n.tulate distal end slightly more bent ventrad than in Mizotrechus poirieri , moderately curved in lateral aspect, ventral margin proximal to apex straight then evenly curved to apex; endophallus with complexly folded tracheal fields; phallobase hooded and slightly crested, opening more or less 40 degrees off axis of shaft. Parameres large, left a third longer than the right, both broadly rounded, asetose. Female genitalia: Not investigated; however, it is likely similar to that illustrated on Plate 11 .

Dispersal potential.

These beetles are macropterous and capable of flight. They are moderately swift and agile runners.

Way of life.

The type series was collected in a flight intercept trap in the rainforest understory at four locations in Guyane. Adults are active in March, April, June, August, October, November, and December, during both the rainy and dry seasons.

Other specimens examined. Paratypes.

Guyane, Saut Pararé, Arataie River, Nouragues Field Station, 51 m, 4.0378°N, 52.6725°W, 26 April 2010 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP127064, female), 15 June 2010 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP127062, ADP127062, females), 24 August 2009 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP124892, female), 10 October 2009 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP124898, male), 30 November 2009 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP124900, female); Mount Itoupe, 570 m, 3.0148°N, 53.0721°W, 17 March 2010 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP126484, 126486, males); Montagne des Chevaux, Commune de Roura, RN2 PK22, 90 m, 4.7127°N, 52.3966°W, 9 August 2009 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP124958, male), 13 December 2009 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP124962, male); Reserve Tresor, Commune de Roura, Route de KAW km 18, 250 m, 4.6104°N, 52.2790°W, 21 November 2009 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP124972, male), Saül, Commune de Saül, Belvédère de Saül, 283-325 m, 3.6223°N, 53.2159°W, 17 November 2010 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP127169, male), Commune de Regina, Reserve Naturelle des Nouragues Inselberg, Petit Plateau, 144 m, 4.0833°N, 52.6833°W, 5 June 2010 (S Brule, PH Dalens, & E Poirier)(NMNH: ADP127157, male), 27 October 2010 (NMNH: ADP127165, male).

Geographic distribution. ( Fig. 40 ). This species is currently known from six localities in the lowlands and midlands of Guyane.

Figures

Plate 3. Digital Photo-illustrations, habitus, dorsal aspect: 9 Mizotrechus fortunensi s sp. n., ABL = 8.7 mm, male holotype, ADP 124968; type locality. 10 Mizotrechus gorgona. sp. n., ABL = 8.4 mm, female Holotype, ADP 128622; type locality. 11 Mizotrechus grossus sp. n., dorsal aspect, ABL = 8.9 mm, male paratype, ADP 127169; type locality. 12 Mizotrechus jefe sp. n., ABL = 6.6 mm, male paratype, ADP 011173; type locality.

Plate 6. Digital Photo-illustrations, anterior femur, ventral aspect: 19 Mizotrechus minutus sp. n., ADP 124966; type locality. 20 Mizotrechus dalensi sp. n., ADP 124896; type locality. 21 Mizotrechus chontalesensis sp. n., ADP 127181; type locality. 22 Mizotrechus edithpiafae sp. n., ADP 124948; type locality. 23 Mizotrechus brulei sp. n., ADP 129205; type locality. 24 Mizotrechus gorgona. sp. n., ADP 128622; type locality.

Plate 9. Digital Photo-illustration, male genitalia, median lobe, left lateral, dorsal, and right lateral aspects: 31 Mizotrechus fortunensis sp. n., ADP 124590; type locality. 32 Mizotrechus grossus sp. n., ADP 127165; type locality. 33 Mizotrechus marielaforetae sp. n., ADP 127183; type locality.

Plate 11. Figure 37. Digital Photo-illustration, female genitalia: Mizotrechus dalensi sp. n., ADP 127161; Petite Montague Tortue, Guyane. A. Dorsal aspect. Legend, bc, bursa copulatrix; co, common oviduct; sg, spermathecal gland; sgd, spermathecal gland duct; sp, spermatheca. dorsal aspect; vc, villous canal; lt, laterotergite; gc 1, gonocoxite 1; gc 2, gonocoxite 2. B. Gonocoxite 2, dorsal aspect: Legend, b, base of gonocoxite 2; bl, blade of gonocoxite 2; des, dorsal ensiform seta; ves, ventral ensiform setae.

Plate 12. Figure 38. Digital Photo-illustration, pygidial (defense) gland system: Mizotrechus grossus sp. n., dorsal aspect, ADP 127064; type locality. Legend: cc, collecting canal; ed, efferent duct; edbl, efferent duct, basal lobe; gldr, pygidial gland reservoir. Ovipositor sclerites, Legend: gc 1, gonocoxite 1; gc 2, gonocoxite 2; lt, laterotergite.

Figure 39. Distribution symbol map for known localities of Mizotrechus chontalesensis, Mizotrechus costaricensis, Mizotrechus fortunensis, Mizotrechus gorgona, Mizotrechus jefe, Mizotrechus woldai, spp. n.

Figure 40. Distribution symbol map for known localities of Mizotrechus batesi, Mizotrechus bellorum, Mizotrechus belvedere, Mizotrechus brulei, Mizotrechus dalensi, Mizotrechus grossus, Mizotrechus marielaforetae, Mizotrechus minutus, Mizotrechus poirieri, Mizotrechus neblinensis, spp. n.