Pediacus Shuckard
Creators: name: Marris, John W. M.
name: Ślipiński, Adam
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Cucujidae
Pediacus

description: Pediacus Shuckard
Pediacus Shuckard, 1839: 150, 185.
Type species. Cucujus dermestoides Fabricius, 1792: 96, by monotypy.
Diagnosis. Pediacus species may be distinguished from the other two genera known from Asia and Australasia, Cucujus and Platisus, by the following characters: size small (length 2.6 –4.7 mm), temples absent or reduced to a small tooth-like projection, antennae with a well-developed three-segmented club.
Description. As for Thomas (2004) but with the following changes: pronotum with anterior angle obtuse to acute; elytra broadly rounded to moderately costate or carinate sublaterally.
Biology. There is little information available about the biology of Pediacus. As for other cucujids, Pediacus are apparently found under bark. In his revision of the North American fauna, Thomas (2004) noted that they are predominantly found under bark of dead conifers. There is minimal collection data available among the specimens examined in this revision. This includes: ‘dead oak bark’; ‘large cut tree- Quercus sp.’; ‘on spruce’; ‘small cut sapling’; ‘light trap’; ‘insect flight trap’ and ‘sifted moss and bark’. Several specimens were collected from high altitudes, ranging up to 2000 m, and for one species, P. montivagus, ca. 2500 to 3600 m.
Little is known about Pediacus larvae. They are likely to be predacious, as is apparently the case for the larvae of Cucujus and Platisus zelandicus Marris & Klimaszewski (Smith & Sears 1982; Watt et al. 2001).
Key to Pediacus adults of Asia and Australasia
1. Pronotum strongly explanate with broad glabrous lateral margins (Figs. 1 A, B), pronotal disc broadly planar P. at e r Grouvelle
- Pronotum not strongly explanate and lacking broad glabrous lateral margins, pronotal disc convex to impressed.......... 2
2(1) Head with small but distinct postocular denticle (Figs. 7 F, 9B)................................................. 3
- Head lacking a distinct postocular denticle................................................................. 4
3(2) Pronotum usually with disc distinctly darker than surrounding areas, anterior denticle small and broadly obtuse (Fig. 9 B); male genitalia with short, globular parameres (Fig. 9 D)....................................... Pediacus sinensis sp. nov.
- Pronotum colouration uniform, anterior denticle more or less obsolete (Fig. 7 F); male genitalia with elongate parameres (Fig. 7 G)............................................................................. P. montivagus Champion
4(2) Elytra broad (<1.95× longer than wide).................................................................... 5
- Elytra elongate (>2.00× longer than wide).................................................................. 8
5(4) Elytra with sublateral margins of disc carinate (Fig. 3 I).................................. Pediacus carinatus sp. nov.
- Elytra with sublateral margins of disc costate to broadly curved................................................. 6
6(5) Pronotum anterior angles rounded (Fig. 5 A), disc of pronotum convex............................. P. f us c us Erichson
- Pronotum anterior angles with an acute projecting denticle, disc of pronotum weakly to moderately impressed.......... 7
7(6) Pronotum with sides convergent anteriorly, anteromedial denticle distinctly produced (Fig. 8 A) Pediacus pendleburyi sp. nov.
- Pronotum with sides subparallel anteriorly, anteromedial denticle weak to obsolete (Fig. 3 A)...... P. bhutanicus Sen Gupta
8(4) Eyes large, coarsely faceted, with facets distinctly convex (Figs. 2 A, B); body colour pale orange-brown (Figs. 2 E, F)..................................................................................... Pediacus australis sp. nov.
- Eyes variable in size, finely faceted, with facets faintly convex; body colour variable.............................. 9
9(8) Pronotum anterior angles with a distinctly produced, acute to narrowly obtuse denticle............................. 10
- Pronotum anterior angles broadly obtuse, blunt or rounded, lacking a distinct denticle.............................. 14
10(9) Pronotum with sides convergent anteriorly (Figs. 4 A, 10A)................................................... 11
- Pronotum with sides parallel in anterior half............................................................... 12
11(10) Antennae relatively broad, antennomere III distinctly broader than IV (Fig. 10 C)............... Pediacus thomasi sp. nov.
- Antennae relatively slender, antennomere III faintly broader than IV (Fig. 4 B)................... P. elongatus Sen Gupta
12(10) Pronotum anterior angles with a small but distinct denticle (Fig. 8 E), disc deeply impressed anteriorly... P. rufipes Grouvelle
- Pronotum anterior angles with a strongly produced acute to narrowly obtuse denticle, disc not deeply impressed anteriorly. 13
13(12). Eyes large and strongly projecting (ocular index <0.70), relatively coarsely faceted; pronotum with weakly projecting obtuse denticles (Fig. 10 E)............................................................ Pediacus taiwanensis sp. nov.
- Eyes smaller and less strongly projecting (ocular index>0.70), finely faceted; pronotum anterior angles with strongly projecting acute denticles (Fig. 7 A)........................................................... Pediacus leei sp. nov.
14(9) Elytra strongly elongate (>2.20× longer than wide) (Fig. 4 H)............................ Pediacus fujianensis sp. nov.
- Elytra less strongly elongate (<2.20× longer than wide)...................................................... 15
15(14) Eyes small, weakly projecting (ocular index>0.80) (Fig. 6 E)................................... P. kurosawai Sasaji
- Eyes larger, more strongly projecting (ocular index <0.78).................................................... 16
16(15) Pronotum with disc deeply impressed, setation short and inconspicuous, punctures sparse and weakly impressed medially (Fig. 9 F)........................................................................ P. smi rnovi Nikitsky and Belov
- Pronotum with disc moderately impressed, setation conspicuous, punctures dense and more strongly impressed medially.. 17
17(16) Pronotum colouration uniform, anterior angles broadly obtuse (Fig. 5 F).................. Pediacus japonicoides sp. nov.
- Pronotum usually with disc distinctly darker than surrounding areas; anterior angles rounded (Fig. 6 A).. P. japonicus Reitter
description: Published as part of Marris, John W. M. & Ślipiński, Adam, 2014, A revision of the Pediacus Shuckard 1839 (Coleoptera: Cucujidae) of Asia and Australasia, pp. 32-58 in Zootaxa 3754 (1) on pages 34-35, DOI: 10.11646/zootaxa.3754.1.2, http://zenodo.org/record/252769