Diochus panamaensis, Irmler, 2017

Irmler, Ulrich, 2017, A review of the Neotropical genus Diochus ERICHSON, 1840 (Coleoptera: Staphylinidae: Staphylininae), Beiträge Zur Entomologie = Contributions to Entomology 67 (1), pp. 1-62 : 24-25

Diochus panamaensis spec. nov.

urn:lsid:zoobank.org:act:989703D5-6335-4E97-8772-B999831203C3

Figs 26A–C , 39K , 44B

Type material: male, Holotype: Panama: Chiriqui Prov., Cerro Colorado , trail to peak, 1475 m elev., litter at burn tree fern, 28.1.1981, leg. W. Suter ( FMNH).

Paratypes: 2 females with same data as holotype ( FMNH) ; same location, but litter shelf-pocket along reopened trail, female, 23.1.1981, leg. W. Suter ( FMNH) ; same location, but cloud forest, Qda. 3w, 1460 m elev., moss on rocks with sphagnum , 1 male, 1? (abdomen lost), 18.1.1981, leg. W. Suter ( FMNH) ; same location, but 1490 m elev., conc. of woody slash, small clearing , 4 males, 8 females, 11.1.1981, leg. W. Suter (12 FMNH, 2 UIC); Bocas del Toro Prov., Cerro Colorado (W), Qda. 1w, 1450 m elev., debris on forested slope , 1 male, 3 females, 8.1.1981, leg. W. Suter ( FMNH) ; same location, but litter at stump, 1475 m elev ., 2 females, 28.1.1981, leg. W. Suter ( FMNH) ; 25 km NNE San Felix (8°34‘N, 84°50‘W), 1500 m elev., Berlese, conc. of loose root mat nr. ridge top Qda, Alicia cloud forest , 1 male, 3 females, 6.6.1980, leg. J. Wagner ( FMNH) ; same location, but soil u. litter and roots, Berlese, 1500 m elev., female, 17.6.1980, leg. J. Wagner ( FMNH) ; same location, but Berlese , forest floor conc., Quebrada Alicia cloud forest , 2 males, 1 female, 9.6.1980, leg. J. Wagner ( FMNH) ; same location, but Berlese, floor litter & mat u. epiphyte log Qda. Alicia cloud forest, male, 8.6.1980, leg. J. Wagner ( FMNH) ; same location, but Berlese, sawdust nr tree hole, Quebrada Alicia cloud forest, female, 10.6.1980, leg. J. Wagner ( FMNH) ; same location, but Berlese , soil beneath litter, Quebrada Alicia cloud forest , 1 male, 1 female, 11.6.1980, leg. J. Wagner ( FMNH) ; same location, fl. litter on slopes, 1500 m elev ., 2 males, 3 females, 4.4.1980, leg. J. Wagner ( FMNH) ; Panama Prov., Cerro Campana, 3200 ft. elev., Berlese, forest leaf litter, female, 14., 23.2.1976, leg. A. Newton ( FMNH) .

Diagnosis: The species is certainly closely related to D. mexicanus due to the reduced eyes and elytra. Within the species group it can be easily identified by the extremely short elytra that are 1.4 times wider than long and 0.7 times as long as pronotum. In the similar D. mexicanus , the elytra are only 1.2 times wider than long and 0.8 times as long as pronotum. Similarly short elytra are also found in D. curtipennis from southern South America. However, this species is placed in the D. schaumii-group due to the structure of the aedeagus.

Description: Length: 3.4 mm. Colouration: brown; elytra slightly darker brown than remaining body; legs light brown; antennae with antennomeres 2 to 7 brown; first antennomere light brown; antennomeres 8 to 11 continuously clearer from antennomere 8 light brown to antennomere 11 yellow.

Head: 0.45 mm long, 0.37 mm wide; eyes small; temples three times longer than eyes; EL: HL = 0.19; temples distinctly divergent posteriad; PW: EW = 1.23; posterior margin rounded, but centrally straight; postrior angles obtusely rounded; setiferous punctures deep; along impunctate midline with row of 4 to 5 punctures; laterad with dense punctation; microculpture dense and deep; transversely reticulate; surface matt.

Antennae slightly longer than head; first antennomere thicker and slightly longer than second; second antennomere conical; slightly longer than its apical width; third antennomere as long and wide as second; forth antennomere quadrate, following antennomeres wider than long; seventh and eighth antennomere 1.5 times as wide as long; all antennomeres with short apical setae; setae on basal antennomeres longer; all antennomeres pubescent.

Pronotum: 0.60 mm long, 0.49 mm wide; sides nearly parallel; anterior half widely rounded; without angles; obtuse posterior angles shortly rounded; lateral margin fine; in dorsal aspect, only visible in posterior half; along impunctate midline with row of three pairs of punctures; interstice between anterior pair of punctures more than twice as wide than between posterior pairs of punctures; laterad second row with four punctures; several setiferous punctures along lateral margin; without microsculpture; surface polished.

Elytra: 0.41 mm long, 0.57 mm wide; sides divergent from shoulders to posterior margin; posterior margin deeply emarginate; shoulder obtuse; setiferous punctures in irregular rows; first row adjacent to suture constisting of 3 to 4 punctures; laterad on disc two more rows; along lateral margin with several setiferous punctures; with weak ground sculpture; surface slightly shiny.

Abdomen densely pubescent.

Aedeagus moderately thick; seminal vesicel of endophallus 0.6 times as long as total length of central lobe; basal inner duct shortly looped; ending in stronger sclerotised structure with forceps; pairs of hook-like sclerotised structures near apex; parameres shorter than central lobe; basal part straight; with short triangular process at middle; apical part elongate; curved; with three setae at upper side; several sensillae at middel part of paramere.

Spermatheca: 0,36 mm long, 0.19 mm wide; bursa copulatrix outside circularly coiled duct.

Etymology: The species name derived from the country’s name, where it was collected.

Figures

Figs 44: Fore-bodies of Diochus pumilio (A), D. panamaensis (B), D. angustiformis (C), D. brunneus (D), D. schaumii (E), D. argen-

Figs 26–29: Diochus maculicollis group: D. panamensis (26), and Diochus schaumii-group D. schaumii (27), D. angusti-

Fig. 39: Spermathecae of Diochus inornatus-group: D. schuelkei (A), D. plaumanni (B), D. tricolor (C), D. vicinus (D); Diochus maculicollis-group: D. brooksi (E), D. ecuadoriensis (F), D. maculicollis (G), D. pumilio (H), D. peruvianus (I), D. mexicanus (J), D. panamaensis (K); Diochus schaumii-group: D. angustiformis (L); scale bar: 0.1 mm.