Deretaphrus aequaliceps Blackburn, 1903

Lord, Nathan P. & McHugh, Joseph V., 2013, A Taxonomic Revision of the Genus Deretaphrus Newman, 1842 (Coleoptera: Cucujoidea: Bothrideridae), The Coleopterists Bulletin (mo 12) 67, pp. 1-107 : 16-17

Deretaphrus aequaliceps Blackburn, 1903

( Figs. 57 , 82–83 , 140 , 177 , 183–184 )

Deretaphrus aequaliceps Blackburn, 1903: 127 . Carter and Zeck 1937: 200–201; Heinze 1943: 119.

Diagnosis. This species can be readily distinguished from congeners by the impressed anterior portion of the head, the distinctly anteriorly narrowed pronotal median longitudinal canal, the well-defined anterior pronotal angles, the strongly transverse submentum, and generally smaller size. It most closely resembles D. viduatus . Due to the extreme size variation within members of the genus, small specimens may be very difficult to identify correctly.

Redescription. Length 4.84–10.36 mm. Width 1.15–2.48 mm. Body elongate, parallel, red to black; dorsal surface glabrous, slightly shiny; ventral surface moderately shiny, glabrous except for minute setae that arise from punctures. Head: In dorsal view, slightly narrowed anteriorly; with supra-ocular ridges, slightly expanded laterally, dorsolateral margin sinuate; eyes visible from above; punctures small and dense, except sparse along posterior margin. Frontoclypeal suture distinct. Clypeus distinctly narrower than head; posterior margin of clypeus slightly incised medially, anterior margin of clypeus broadly arcuate. Submentum shape similar to Fig. 53 ; short and transverse, distinctly separated from subgenal braces, with paired setose pits; anterior margin straight to slightly convex, moderately expanded anteroventrally over oral cavity, apices of palpi visible, part of mentum often visible. Antennal groove well-developed, impunctate. Antenna sparsely setose; segments 2–8 with single transverse row of moderately long setae, setae extending at least to distal margin of antennal segment from which they arise; antennal club segments with sparse setae, setae long and located at or near distal margin of the segment. Antennal club subsymmetrical. Dorsal surface (external face) of mandible with median setose groove. Thorax ( Fig. 57 ): Pronotum elongate, widest near anterior ¼, distinctly wider than head; dorsal surface flattened to slightly impressed at middle, convex laterally; anterior margin arcuate; anterior angles produced, nearly right angles, slightly rounded; posterior margin slightly sinuate, distinctly narrower than elytral bases; posterior angles pronounced, with small denticle; lateral margin with incomplete carina, forming a distinct raised border in dorsal view. Pronotal disc with small, dense, oval punctures. Pronotal median longitudinal canal well-developed, interrupted to form a weakly impressed, anterior portion and a posterior canal; interruption of the canal impunctate; anterior fovea a small slit or merely a depression; posterior canal elongate, narrow and triangular (isosceles) widest at base and narrowing to a sharp point anteriorly; internal lateral margins of canal grooved. Hypomeron minutely punctate; lateral walls nearly vertical. Prosternum flat medially, strongly deflexed at lateral margin. Tergosternal suture slightly sinuate; located on lateral wall of prothorax. Elytra ( Figs. 82–83 ): Elytron flattened dorsally, convex laterally; interstitial intervals 5 and 7 carinate for entire length, more pronounced near apex. Interval 3 raised near apex only. Intervals 3, 5, and 7 with micropunctures at crest. Basal elytral margin with intervals 3 and 5 ending in a weak, knob-like protuberance. Elytral shoulder with weakly developed finger-like callosity. Legs: Setation sparse; inner face of tibia with a double fringe of moderately long setae. Tarsus sparsely setose except for 2 pockets of dense setae on the ventral surface near apex of tarsomeres 1–3 and a few erect setae at apices of tarsomeres. Abdomen: Ventrite V more densely punctured than preceding segments. Aedeagus: Phallobase as in Fig. 140 . Tegmen consisting of paired, subtriangular plates at middle;

plates narrowly touching medially. Basal piece with short anterolateral struts; struts slightly curved anteriorly. Parameres moderately short, broadly rounded, distinctly separated and individually articulated to phallobase, internal lateral margins arcuate; paramere sparsely setose with short setae at apical margin; dorsal surface of paramere with short subtriangular process; process thickest at base, narrowing apically, slightly shorter than half the length of the paramere, apex slightly swollen; processes narrowly separated, parallel medially. Penis similar to Fig. 169 ; short, moderately thick, more or less straight; apex narrowed and pointed; base slightly expanded, bearing short, paired anterior struts. Penis slightly lighter in color near base.

Variation. Size and color vary strongly within the species. The width of the median longitudinal pronotal canal is also somewhat variable, ranging from narrower in smaller specimens to wider in larger specimens.

Distribution. Australia: New South Wales, Queensland, and Victoria ( Fig. 177 ).

Biology. Not known.

Remarks. Blackburn (1903) did not mention the number of specimens examined. In order to stabilize this name, a lectotype is here designated from the syntype series of D. aequaliceps .

Type Locality. Victoria (Dividing Range) .

Type Material Examined. L E C T O T Y P E ( Figs. 183–184 ) ( BMNH, pinned; right elytron broken, glued on card beneath specimen) : “ Type H.T. [round label with orange border] // 7204 Healesville T. [“7204” and “ Healesville ” written in red ink, “T.” written in black ink, in Blackburn’ s hand] // Australia. [red underline] Blackburn Coll. B.M. 1910-236. // Deretaphrus aequaliceps Blackb [in Blackburn’ s hand]” [ BMNH 95 NL, examined]. Sex not determined.

Additional Material Examined (32). AUSTRALIA: NEW SOUTH WALES: Kyogle ( ANIC 171 NL); Mongarlowe River ( ANIC 166 NL); Nimmitable, 6 km. N ( ANIC 240 NL); Tumut River ( BPBM 38 NL). QUEENSLAND: North Queensland ( ANIC 35 NL). SOUTH AUSTRALIA: Yorketown ( FMNH 22 NL); no locality ( BMNH 3 NL). VICTORIA: Broadford ( BPBM 24 NL); Carrum ( MVMA 110 NL); Edenhope ( SAMA 116 NL); Eltham ( MVMA 56 NL, MVMA 64 NL); Fern Tree Gully ( MVMA 4 NL); Hamilton ( MVMA 6 NL, MVMA 52 NL); Healesville, Coranderrk Res. ( ANIC 247–248 NL); Melbourne ( OUMNH 14 NL, SAMA 144 NL, UQIC 26 NL); Mordialloc ( BMNH 16 NL); Ringwood ( MVMA 49 NL); no locality ( ANIC 207 NL, MVMA 57 NL). STATE UNKNOWN: Kangaroo ( MVMA 44 NL). NO LOCALITY: ANIC 39 NL, ANIC 44 NL, BMNH 2 NL, BMNH 93 NL, MCZ 30 NL, MCZ 38 NL, MVMA 54 NL.

Figures

Figs. 57–65. Deretaphrus species, pronotum. 57) D. aequaliceps; 58) D. alveolatus; 59) D. analis; 60) D. antennatus;

Figs. 82–87. Deretaphrus species, elytra, dorsal and lateral views. 82–83) D. aequaliceps; 84–85) D. alveolatus;

Figs. 140–148. Deretaphrus species, phallobase. 140) D. aequaliceps; 141) D. alveolatus; 142) D. analis;

Figs. 177–178. Distribution of Deretaphrus species. 177) D. aequaliceps, D. erichsoni, D. iridescens, and D. ocularis;

Figs. 183–191. Primary type specimens and specimen labels of Deretaphrus species. 183–184) D. aequaliceps, lectotype, BMNH; 185–186) D. alveolatus, holotype, SAMA; 187–188) D. analis, lectotype, SAMA; 189–190) D. antennatus, holotype, WAMP; 191) D. boliviensis, holotype, USNM.

Figs. 48–53. Deretaphrus species, head capsule, ventral view, showing setae and shape of submentum. 48) D. ignarus;

Figs. 165–172. Deretaphrus species, penis (left: dorsal view; right: lateral view; phallobase, to scale with penis). 165) D. boliviensis; 166) D. bucculentus; 167) D. gracilis; 168) D. hoplites; 169) D. ignarus; 170) D. oregonensis; 171) D. parviceps; 172) D. puncticollis.