Lepanus pecki Gunter & Weir, 2019

Gunter, Nicole L. & Weir, Thomas A., 2019, Revision of Australian species of the dung beetle genus Lepanus (Coleoptera: Scarabaeidae: Scarabaeinae): key to species groups and description of 14 new species from the L. pygmaeus species group, Zootaxa 4564 (1), pp. 41-80 : 72-73

Lepanus pecki Gunter & Weir , new species

( Figs. 4 D–E, 4I–J, 6D, 9A, 11E, 14)

Type series. Holotype: ♂ “AUST: NT; Darwin CSIRO, McMilliansRd 1-25 xii 1993 FIT S&J Peck 93-87” [12°24'42"S, 130°55'19"E] /“Canadian Museum of NATURE CMNEN-00030268 ” / “ANIC Database 25-065551” / “ Lepanus NT6 det. T.A.Weir 2018 ” / “ANIC Image” in ANIC. Paratypes: Northern Territory: Darwin CSIRO, McMillans Road, [12°24'42"S, 130°55'19"E], 1–25.xii.1993, S.B. & J. Peck ( CMNEN-00030265-00030267 , 2 × ♀, 1 × ♂, 0 0 0 30269 ♀, 00030281–00030285 in CMNC 5 × ♀, CMNEN-00030286–00030287 in QM 1 × ♂ 1 × ♀, CMNEN-00030271- 79 in ANIC 9 × ♀); Darwin CSIRO, McMillans Road, [12°24'42"S, 130°55'19"E], 25.xii.1993 – 10.i.1994, S.B. & J. Peck ( CMNEN-00030252–00030258 in CMNC 1 × ♂, 6 × ♀, CMNEN- 00030259–00030260 in QM 2 × ♀, CMNEN-00030262–00030263 in ANIC 1 ♂, 1 ♀); 5 km SE Humpty Doo, Byrne , [12°38'S, 131°16'E], 11–13.i.1992, D. Bickel (K266973, ANIC 25- 060801 in AM 1 × ♂, 1x ♀) .

Description. Either uniformly dark brown or bicoloured with head and pronotum dark brown and rest of the body light brown. Antennal clubs grey to yellow.

Total length: 2.0– 2.1 mm. Holotype measurements: Total length 2.0 mm, elytral width 1.3 mm.

Male: Head: U-shaped between clypeal teeth, which are short, blunt, and upturned. Margin slightly angulate at clypeogenal suture. Genal angle weakly defined. Basal carina present and interrupted medially. Dorsal part of eyes narrow in size, separated by interocular space approximately 15 times eye width (30:2); eye canthus nearly dividing eye. Head 1.15 × wider than long (37:32).

Prothorax: Hypomeral surface finely reticulate. Hypomeral striae about half the length of hypomeron. Pronotum 1.7 × wider than long (60:35).

Elytra: Striae 1–3 narrow and double; striae 4–7 single. Elytra 1.3 × wider than long (78:60).

Legs: Three teeth on the outer edge. Front edge of protibiae deeply angulate; apical digit somewhat elongate and sharp. Inner edge of metatibiae expanded approximately midlength, creating a distinct flange. Metatarsi with 2nd tarsomere subequal to the 5th. Tarsal claws small and toothed.

Abdomen: Pygidium with almost ovoid depression with angulate upper edge and containing a round tubercle in upper third. Depression occupies at least half size of disc and just extending under the angulate upper edge of pygidium. Abdominal surface smooth and non-reticulate. Segment 6 punctate.

Pterothorax: Medial lobe of metaventrite finely punctate and broadly margined between mesocoxae. Lateral lobe of metaventrite smooth and punctate with setae. Meso-metaventral suture very slightly arched. Mesoventrite with slight notch anteriorly. Mesoventrite and mesepimeron smooth. Metanepisternum reticulate.

Female: As per the L. pygmaeus species group.

Etymology. Named in honour of Stewart Peck, Canadian Museum of Nature, Ottawa, Canada, who collected the majority of known specimens and many other Lepanus from the Northern Territory that are included in this study.

Distribution. Known only from mixed eucalypt woodland and in monsoon woodlands of Darwin and Humpty Doo in the Northern Territory IBRA region DAC ( Fig. 14 ). Very limited sampling of dung beetles have been conducted in DAC and the neighbouring VIB, DAB, PCK, ARP, and ARC IBRA regions and L. pecki may be more widespread than currently reported.

Comments. Lepanus pecki was unknown at the time when the informal nomenclature for undescribed species of Lepanus was reported ( Yeates et al. 2011) but was designated the informal name “ Lepanus NT6” within this revision. This species has been collected in flight-intercept traps and pan traps. It is differentiated from all other Lepanus species (except L. guthrieae ) by males having a distinctive flange on the metatibiae. Furthermore it is one of only two species in the L. pygmaeus species group that have three protibial teeth, the other being L. sauroni .

Figures

FIGURE 4. Some diagnostic characters of the Lepanus pygmaeus species group. A, Head of Lepanus guthrieae featuring medially interrupted basal margin (white arrow) and reticulations on clypeal area only (black arrow); B, head of Lepanus lentil featuring angulate and complete basal margin (white arrow); C, pterothorax of Lepanus andersonorum showing fine, short carina extending backwards from the meso-metaventral suture (white arrow); D, posterior aspect of metatibia of Lepanus pecki; E, anterior aspect of metatibia of Lepanus pecki; F, anterior aspect of metatibia of Lepanus guthrieae; G, female protibia of Lepanus pygmaeus; H, male protibia of Lepanus pygmaeus; I, female protibia of Lepanus pecki; J, male protibia of Lepanus pecki; K, male protibia of Lepanus crenidens; L, male protibia of Lepanus pungalina; M, inner laterodorsal aspect male protibia of Lepanus pungalina showing bent apical digit (black arrow).

FIGURE 14. Map of known records for 10 species within the Lepanus pygmaeus species group overlaid with predicted distribution boundary of L. pygmaeus (dashed line) taken from Fig. 13 map.