Athoplastus rainieri ( Van Dyke, 1932 ) Etzler & Johnson, 2018

Etzler, Frank E. & Johnson, Paul J., 2018, Athoplastus Johnson and Etzler (Coleoptera: Elateridae: Dendrometrinae), a New Genus of Click Beetle from the Northwestern Continental USA, The Coleopterists Bulletin 72 (3), pp. 503-521 : 517-518

Athoplastus rainieri ( Van Dyke, 1932) , new combination

(Adult: Figs. 4 , 8 , 22–24 , 28 )

Ludius rainieri Van Dyke 1932: 397 , 421.

Ctenicera rainieri ( Van Dyke, 1932) ; Lane 1971: 32.

Diagnosis. This species is distinguished from all other species of the genus by the combination of close pronotal punctures (separated by less than one diameter of a puncture) ( Fig. 10 ), sloped prosternum ( Fig. 8 ), and dark markings at each puncture along the striae of the elytra ( Fig. 4 ). This last character is likely not a good species-level character and may be related to specimen development. Athoplastus rainieri is quite similar to A. palouse , which can be distinguished as noted above.

Description. Male. Length 16 mm, width 4 mm (measured across bases of elytra). Red-brown, carina and tips of mandibles darker; antennae, palps, coxae, and tarsi lighter, almost tawny yellow ( Fig. 4 ). Head: Ocular index = 61.1. Antennae: Ratio of antennomeres (2–11): 1: 1.25: 3: 3.25: 3.5: 3.25: 3.75: 2(?): X: X. [Antennomere 9 appears to be broken, and 10 and 11 are missing on the specimen measured.] Pronotum: 1.1X wider than long. Lateral margin completely carinate, slightly sinuate, almost subparallel anterad hind angles; convergent and slightly dorsoventrally flattened along lateral edges on anterior fourth. Punctures distinct, subumbilicate and dense on disc, separated by less than 0.2X their own diameter, with 2 “dimples” on either side of midline just anterad midlength, with less close punctures; punctures becoming clearly umbilicate and denser along anterior and lateral margins. Prosternum: Slightly convex with dense, shallow, umbilicate punctures; anterior lobe short, broadly rounded, shallowly deflexed. Posterior process short and arcuate, gradually raised ventrally between procoxae, then sharply deflexed posteriorly; distinct ridge present immediately before procoxal cavity and along ventral surface of prosternal process. Legs: Tarsomere 5 equal to tarsomere 1 on pro- and mesotarsi, tarsomere 5 missing on both metatarsi. Elytra: Elongate, subparallel, 4X pronotal length; striae shallowly impressed, deeper apically, punctures marked by darkening of the integument; intervals shallowly convex, punctures fine, shallow, and irregularly distributed. Aedeagus ( Figs. 22–24 ): Basal piece approximately 1/3 total length, with deep, narrowly U-shaped, membranous section on ventral surface ( Fig. 23 ); median lobe 1.2X length of parameres, slightly deflexed ventrally at tip, median carina on ventral surface, basal struts following edges of median lobe; parameres wide basally, edges slightly sinuate and gradually narrowing toward tip, tip with subacute lateral expansion bearing 2 setae ( Fig. 24 ).

Female. Length 21 mm, width 5 mm (measured across bases of elytra). Yellow-brown. Head: Ocular index = 72.7. Antenna: Ratio of antennomeres 2–11: 1: 1.6: 2.2: 2: 1.8: 1.6: 1.8: 1.6: X: X: X. [Note: Antennae are broken on specimen examined, so the last three antennomeres of longest intact antenna are missing.] Pronotum: 1.25X wider than long, hind angles divergent, sides broadly sinuate. Legs: Tarsomere 5 intermediate in size between tarsomeres 1 and 2 on metatarsi; pro- and mesotarsi as in male. Scutellar shield: Setae radiating from midline.

Specimens Examined (3). Male. Holotype. USA: WASHINGTON: [Pierce Co.]; Mt. Rainier [E.C. Van Dyke, date unknown] ( CASC, 1, CASC type no. 3181). Female. USA: WASHINGTON: [Kittitas Co.] Lk. Cle Elum; 13.v.1936; M.C. Lane (1, USNM); Lk. Cle Elum [?], 26.v.1937, M.C. Lane (1, USNM).

Distribution. This species is only known from the Cascade Range of mountains in Washington.

Taxonomic Remarks. Van Dyke (1932) mentions a specimen seen “in the collection of Prof. W. J. Chamberlin at Corvallis, Oregon.” Chamberlain’ s collection was deposited at the Oregon State Arthropod Collection (OSAC) at Oregon State University ( Oman 1970). However, a search of the OSAC yielded no specimen matching this description.

Figures

Figs. 1–4. Athoplastus species, dorsal habitus. 1) A. acutus; 2) A. palouse; 3) A. lochsa; 4) A. rainieri.

Figs. 5–9. Athoplastus species. 5) A. acutus, female dorsal habitus; 6) A. acutus, male dorsal habitus, darker coloration; 7) A. acutus, male ventral habitus; 8) A. rainier, prothorax, lateral view (arrow indicates start of area between procoxae); 9) A. acutus, prothorax, lateral view (arrow indicates start of expanded area between procoxae).

Figs. 16–27. Athoplastus species, adeagi, dorsal view, ventral view, and close up of paramere apex, respectively.

Figs. 28–30. Athoplastus species. 28) A. rainier, female, internal genitalia, v = vagina, u = uterus, acgld = accessory gland, bc = bursa copulatrix (after Han et al. 2012); 29) Distribution map of examined specimens, with rivers; 30) Neighbor-joining tree of Montana populations of A. acutus, COI mtDNA, 500 runs, scale bar = 1% difference.

Figs. 10–15. Athoplastus species. 10) A. acutus, prothorax, dorsal view; 11) A. lochsa, prothorax, dorsal view; 12) A. acutus, left antenna; 13) A. lochsa, left antenna; 14) A. palouse, left antenna; 15) A. acutus, female, left wing. Scale bars for antennae = 1 mm; for wing = 5 mm.