Pediomorphus Chaudoir 1878: 28

Will, Kipling, 2019, Taxonomic Review of the Australian Genus Pediomorphus Chaudoir, 1878 (Coleoptera: Carabidae: Abacetini), The Coleopterists Bulletin 73 (3), pp. 629-645 : 630-644

Pediomorphus Chaudoir 1878: 28

Type Species. Pediomorphus planiusculus Chaudoir, 1878 , by monotypy.

References to Genus. Masters 1885; Sloane 1895, 1898, 1900, 1915; Tschitscherine 1902; Straneo 1960; Moore 1965, 1967; Moore et al. 1987; Liebherr and Will 1998; Lorenz 2005a, b; Will and Park 2008; Will 2010, 2015.

Generic Diagnosis. Typical Loxandrina recognizable by the combination of the enlarged apical labial palpomeres with a setose, ventral sensorium ( Fig. 14 ), subocular carina ( Fig. 18 ), presence of an elytral plica, and lack of elytral discal setae. The characteristic labial palps are not known from any other Abacetini.

Genus Characteristics. Modified from Moore (1965). Small to medium size beetles (3.5–8.2 mm); pale brown, castaneous, or rarely darker, nearly piceous; parallel-sided, somewhat or extremely dorso-ventrally depressed body form; relatively large pronotum ( Figs. 1–13 ); apical segment of labial palpi enlarged, subglobose, plurisetose, with a setose, ventral sensorium ( Fig. 14 ); mentum triangular, shallowly emarginate; epilobes long and narrow, not prominent; median tooth prominent and entire or slightly emarginate, not reaching tips of lobes, paramedial pits absent; paraglossae short, glabrous; antennae long, filiform, with 3 basal segments glabrous; postocular orbits not pronounced; elytra free, fully striate, border entire across base, epipleural plica present, but often very small, parascutellar stria present, joined to stria 1, angular base of stria 1 absent, no discal punctures, 13–15 umbilicate setae in stria 8, humeri rounded; hind wings full size; male anterior tarsi with 3 basal segments dilated and squamose beneath; aedeagus ( Figs. 21–32 ) with orifice on dorsum; parameres conchoid, the right smaller than the left.

KEY TO THE SPECIES OF ADULT PEDIOMORPHUS

1. Pronotum without evident marginal bead from hind angle to, or nearly to, basal impression; at most, lateral bead slightly extended along base beyond hind angle and ended or broadly interrupted by irregular punctation, or margin with a very shallow, usually irregular groove ....................... 2

1 ʹ. Pronotum with marginal bead evident from hind angle to, or nearly to, level of basal impression, set off by a finely impressed submarginal groove, rarely with a few small punctures .......................................... 9

2. Striae coarsely or finely crenulate-punctate. Pronotal base with or without scattered punctures .......................................... 3

2 ʹ. Striae not crenulate-punctate, shallowly sulcate with very shallow, irregular punctures more conspicuous near the base. Pronotum without punctures. Large size for genus,>8.0 mm ........... Pediomorphus maximus Will , new species

3. Elytra concolored or with interval 1 paler .............................................. 5

3 ʹ. Elytra variably bicolored with a black or infuscated region apparent at least centrally on intervals 2–3 on elytral disc, usually reaching interval 5 ( Figs. 1 , 7 ) .............. 4

4. Striae finely punctate, with punctures contiguous or at most with 1 puncture width of separation in basal third of elytra ( Fig. 15 ). Pronotal base with or without scattered punctures ................ Pediomorphus planiusculus Chaudoir

4 ʹ. Striae coarsely punctate, with deep punctures 1–2 puncture widths of separation in basal third of elytra ( Fig. 16 ). Pronotal base without punctures. Proepisternum anteromedially impunctate .......... Pediomorphus crenulatus Will , new species

5. Pronotal hind angles nearly right-angled, lateral margins noticeably, though shortly, sinuate just before hind angle ................ 6

5 ʹ. Pronotal hind angles broadly, obtusely angled, lateral margins at most only very slightly subsinuate just before hind angle ... ....................................................... 7

6. Abdominal ventrites impunctate or with a few scattered, shallow punctulae laterally and across the last ventrite; in some specimens, ventrites irregularly rugose laterally; pronotum and elytra lacking evident microsculpture; small size, 3.0–4.0 mm ............................. ......................... Pediomorphus semilaevis Will , new species

6 ʹ. Abdominal ventrites punctate throughout, though usually less densely medially; pronotum usually with microscuplture evident basolaterally and elytra with evident transversely stretched microsculpture; small or medium size, but typically larger, 4.0–5.0mm .................. ............. Pediomorphus variabilis (Straneo)

7. Pronotum distinctly punctate across entire base. Elytral striae 6–7 deeply, densely punctate throughout their length, similar to other striae, only stria 7 with smaller, less deeply impressed punctures very near base .......................... ......................... Pediomorphus punctatus Will , new species

7 ʹ. Pronotal base not punctate, finely punctulate only in and near basal impressions, or with a few scattered punctures medially and/or laterally. Elytral striae 7 and also frequently 5–6 with smaller, shallower, more widely spaced punctures near base and more shallowly impressed compared with other striae .............................................. 8

8. Small size, about 4.0 mm; head infuscated darker than pronotum and elytra; outer elytral striae very shallowly punctate and impressed, stria 7 not impressed in basal third, all striae impunctate in the apical third .................. ............................ Pediomorphus minor Will , new species

8 ʹ. Medium size,> 4.5 mm; head concolorous with pronotum and elytra; all striae on elytral disc deeply, finely punctate and impressed, stria 7 impressed in basal third, although shallower than other striae, all striae punctate and crenulate except in apical fifth or less ................ ............................. Pediomorphus obtusus Will , new species

9. First antennomere elongate, typical form for genus ( Fig. 18 ). Frontal foveae not impressed, shallow, short or linear. Pronotal base with punctures at least in or near basal impressions ...................................... 10

9 ʹ. First antennomere relatively short and notably swollen ( Fig. 17 ). Frontal foveae impressed and punctate. Pronotal base without punctures.... ................. Pediomorphus macleayi Sloane

10. Entirely concolorous rufous-brown or with a very slightly infuscated head and paler elytral interval 1. Pronotal form variable ......... 11

10 ʹ. Head and elytra piceous, contrasting with rufous-brown pronotum ( Fig. 2 ). Pronotum slightly wider than long, hind angles very broadly obtuse ...................................... .............. Pediomorphus ruficollis Sloane

11. Abdominal sterna impunctate. Body form narrow-elongate. Pronotal anterior angles very slightly produced .................................... .............. Pediomorphus elongatus Sloane

11 ʹ. Abdominal sterna densely and finely punctate or irregularly shallowly punctate laterally. Body form broad. Pronotal anterior angles prominently produced ............... 12

12. Region in and around pronotal basal impressions with distinct, dense punctures; elytral microsculpture not visible at 50X magnification ..................... Pediomorphus robustus Will , new species

12 ʹ. Region around pronotal basal impressions with a few scattered, very shallow punctulae; elytra with perceptible microsculpture that is transversely stretched and somewhat iridescent ..................... Pediomorphus storeyi Will , new species

Figures

Figs. 14–18. Pediomorphus species. P. planiusculus: 14) Labial palp; 15) Base of right elytron. P. crenulatus: 16) Base of right elytron. P. macleayi: 17) Head, showing large antennomere 1. P. robustus: 18) Ventral view of head, arrow indicating subocular carina.

Figs. 1–2. Pediomorphus species, dorsal habitus. 1) P. planiusculus; 2) P. elongatus. Scale bars = 1 mm.

Figs. 3–6. Pediomorphus species, dorsal habitus. 3) P. macleayi; 4) P. ruficollis; 5) P. variabilis; 6) P. maximus, holotype. Scale bars = 1 mm.

Figs. 7–10. Pediomorphus species, dorsal habitus. 7) P. crenulatus, holotype; 8) P. minor, holotype; 9) P. semilaevis, paratype; 10) P. punctatus, paratype. Scale bars = 1 mm.

Figs. 11–13. Pediomorphus species, dorsal habitus. 11) P. robustus, paratype; 12) P. storeyi, holotype; 13) P. obtusus, paratype. Scale bars = 1 mm.

Figs. 21–32. Pediomorphus species, aedeagi, left lateral view (A) and ventral view of tip (B). 21) P. planiusculus; 22) P. elongatus; 23) P. macleayi; 24) P. ruficollis; 25) P. variabilis; 26) P. crenulatus; 27) P. minor; 28) P. semilaevis; 29) P. punctatus; 30) P. robustus; 31) P. storeyi; 32) P. obtusus.