Dipropus approximatus (Candèze)

Johnson, Paul J., 2016, Five new species of Dipropus Germar (Coleoptera: Elateridae) from west-central North America, and a lectotype designation for Elater soleatus Say, Insecta Mundi 2016 (523), pp. 1-27 : 12-17

Dipropus approximatus (Candèze)

Ischiodontus approximatus Candèze 1859: 113, 1891: 61 ; LeConte 1863: 46, 1866: 46; Gemminger and Harold 1869: 1515; Crotch 1873: 70; Horn 1885: 50; Champion 1895: 326; Schwarz 1906: 77; Leng 1920: 174; Schenkling 1925: 88; Blackwelder 1944: 299

Dipropus approximatus of Arnett 1962: 505 (by indication)

Diagnosis. [Characters based on holotype only.] Body 10.0 mm long, 2.2 mm wide; castaneous. Ocular index 58. Antennae long, reaching body midlength; antennomere 2–10 [antennomere 11 missing] length ratio 1.0:3.4.

Pronotum broadly trapezoidal; width 1.2x length.

Aedeagus with basal piece 0.59 of total length, paramere 0.48 of total length, paramere apex 0.30 of paramere length.

Female not associated.

Specimen Examined. Holotype male; “Type / Mex / 72 / coll. Janson, ex Laferte / I. approximatus / approximatus Mann., Reiche , Mexico (part)” ( BMNH). Other labels pertain to the Biologia Centrali- Americana material as described by Johnson (2002).

Notes. Dipropus approximatus is poorly represented in collections, with all examined attributed specimens actually representing other species. The species was described from “ Mexique ” by Candèze (1859) and compared to D. tuspanus (Candèze) . Superficial similarity is also shared with D. elongatus Champion and D. rufulus (Candèze) , also from south-central Mexico. LeConte (1863, 1866) applied the name to specimens from Texas, which are here recognized as D. soleatus (Say) and D. simplex (LeConte) . Horn (1885) stated that D. approximatus from the United States was misidentified and is not in our fauna, an assessment agreed with here. Champion (1895) gave the species only from Mexico.

Clark (1963) recorded this species from Arizona and California, but he apparently relied upon historical identifications and repetitions of catalog records. The holotype male of this species was examined at the Natural History Museum, London. Aedeagal morphology is very similar to that of D. fuscus (LeConte) and D. soleatus (Say) ( Fig. 20 ), and this shared morphology segregates this three-species group from all other described species of Dipropus from south-central Mexico to the United States. No specimens from the study region are known to possess the aedeagal morphology of any of these three species. Misidentifications that demonstrate the historical taxonomic problem included four specimens in the National Museum of Natural History, which were found to represent both D. pericu and D. reinae . Forty specimens from Arizona in the Bohart Museum, University of California-Davis, are here referred to D. reinae . Three specimens of “ I. approximatus ” in the MCZ/LeC, each bearing a silver disc with a cut edge representing ‘Lower California’, are attributed to D. pericu .

Figures

Figures 19-21. Elater soleatus Say lectotype / Ischiodontus oblitus Candèze, holotype. 19) Adult, dorsal habitus. 20) Aedeagus, dorsal aspect. 21) Specimen labels.