Electribius relictus Arriaga-Varela & Escobar

Arriaga-Varela, Emmanuel & Escobar, Federico, 2014, Electribius relictus, a new extant species of Artematopodidae (Coleoptera: Elateroidea) from Veracruz, Mexico, Zootaxa 3895 (2), pp. 292-296 : 293-295

Electribius relictus Arriaga-Varela & Escobar sp. nov.

( Fig. 1–9 )

Type material. Holotype male; México: Veracruz, San Andrés Tlalnehuayocan , Chivizcoyo. 19° 31’ 00.0’’ N, 97° 00’

25.4’’ W. 1637 m.a.s.l. BMM (frag.)—fragmented cloud forest, ex hojarasca—leaf litter, extractor Winkler. 20.IV.2012. Col. F. Alvarado. [Terminal antennomere of right antenna is missing]

Diagnosis. Electribius relictus sp. nov. is distinguished from the other extant species of the genus, E. crowsoni Lawrence and E. similis Lawrence , by the pronotum and elytra completely black; pronotum with lateral margins crenulate at basal two-thirds, abdominal ventrites 3–5 with an additional puncture or pore adjacent to each setiferous puncture, ventrite 5 with medial ridge conspicuous but short; and by the shape of aedeagus.

Description. Body small, elongate, slender, slightly flattened; 2.1 mm long, 2.4 times as long as wide, 3.5 times as long as greatest depth; black, except for antennae, mouthparts and legs which are infuscate orange, with femora slightly darker. Integument somewhat shiny and covered by decumbent to suberect pale golden setae inclined backwards on elytra, and forwards on pronotum. Antenna ( Fig. 2 ) extending behind to anterior third of elytra, 0.5 times as long as body; antennomeres 2–10 slightly widened distally; 11th elongate-oval; ratio of antennomere lengths 1.5: 1.00: 1.30: 1.70: 1.70:1.70: 1.70: 1.70: 1.70: 1.70: 1.95. Pronotum transverse, widest at basal third, 1.8 times as wide as long. Lateral margins slightly crenulate and rounded at basal 2/3, then convergent anteriorly; with a pore near anterior margin; posterior angles obtuse; base with transverse groove joining a pair of large oblique cavities. Prosternal process ( Fig. 3 ) narrow, acuminate apically, about twice as long as procoxae. Scutellum triangular. Elytra elongate, moderately slender, widest at posterior third, 1.85 times as long as wide, 4.1 times as long as and 1.2 times as wide as pronotum; with 11 rows of small setiferous punctures; sutural row with a marked stria which ends at a deep cavity, another deep stria at lateral edge. Epipleura extending just beyond metacoxa. Metasternum 1.6 times longer than wide. Legs slender and moderately long. Metatibia 0.29 times as long as elytra. Metatarsus 0.9 times as long as tibia. Abdomen ( Fig. 4 ) 1.7 times larger than metaventrite; suture between ventrites 2–3 faint, ventrites 3–5 with sutures absent mesally; median ridge short and vague, reaching one third of length of ventrite 5; ventrites 3–5 with an additional pore at base of each setiferous puncture. Phallobase ( Fig. 5 ) large with medial strut distinctly long and lateral struts reduced. Aedeagus ( Figs 6–8 ) 0.34 times as long as median length of ventrites 1–5 combined; parameral tube 1.6 times longer than wide, with apex bilobed; median lobe with a moderately large spine projected dorsally ( Fig. 8 ).

Etymology. The epithet of this species refers to the relictual character of this beetle lineage. It also alludes to the fact that the type locality is a remnant of cloud forest, a highly endangered habitat in the Neotropics.

Bionomics. The specimen was collected during the rainy season using a Winkler extractor to survey the leaf litter, formed mainly by leaves of tree species Platanus mexicana Moric. (Platanaceae) and Liquidambar styraciflua L. ( Altingiaceae ). The locality is situated in a riparian remnant of cloud forest at 1,637 meters above sea level. The place where the sample was taken is situated about 3 meters away from a permanent stream and is spotted with abundant rocks covered by mosses.

Figures

FIGURES 1–8. Electribius relictus sp. nov. (1) pronotum and elytra; (2) antenna; (3) prosternum; (4) abdomen; (5) phallobase, ventral view; (6) aedeagus, ventral; (7) aedeagus, lateral; (8) aedeagus, dorsal.