Mycterus youngi Pollock

Pollock, Darren A., 2012, Mycterus youngi Pollock (Coleoptera: Mycteridae), a New Species from the Great Lakes Region, with a Revised Key to Species of North America, The Coleopterists Bulletin 66 (1), pp. 23-26 : 23-26

Mycterus youngi Pollock , new species ( Figs. 1, 3–6 )

Type Material. Holotype ♂ ( WIRC), labeled: “ Wood Co. Wis [consin]. Griffith St. Nursery VII- 12-1947 R. D. Shenefelt / From Collection of Univ. of Wisconsin / [lge. red label] HOLOTYPE ♂ Mycterus youngi Pollock ”. The holotype is missing the left foreleg, and genitalia are in a microvial pinned beneath the specimen . Allotype ♀ ( WIRC), labeled: “ Wood Co. Wis [consin]. Griffith St. Nursery VIII-4 1947 R. D. Shenefelt / From Collection of Univ. of Wisconsin / [lge. red label] ALLOTYPE Mycterus youngi ♀ Pollock ” . Paratypes: 1 ♀ ( WIRC), labeled: “ Wood Co. Wis [consin]. Griffith St. Nursery VII-25 1947 R.D. Shenefelt / Univ. of Wis. Insect Collection / Mycterus canescens Horn det Arnett ‘ 52 / [lge. blue label] PARATYPE ♀ Mycterus youngi Pollock ” . 1 ♀ ( DAPC), labeled: “ Wood Co. Wis [consin]. Griffith St. Nursery VII-29 1947 R.D. Shenefelt / From Collection of Univ. of Wisconsin / [lge. blue label] PARATYPE ♀ Mycterus youngi Pollock ” . 1 ♀ ( WIRC), labeled: “ Wood Co. Wis [consin]. Griffith St. Nursery VIII-3 1947 R.D. Shenefelt / From Collection of Univ. of Wisconsin / [lge. blue label] PARATYPE ♀ Mycterus youngi Pollock ” . 1 ♀ ( WIRC), labeled: “ Wood Co., Wis [consin]. Port Edwards VII-11 1949 R. D. Shenefelt / L. T. / From Collection of Univ. of Wisconsin / [lge. blue label] PARATYPE ♀ Mycterus youngi Pollock ” . 1 ♂ ( WIRC), labeled: “ USA: WI: Iowa Co. Area Pines-Sand Barrens SNA 43°10′33″N / 89°55′53″W 23 June-1 July 2001 Jeffrey P. Gruber / flight-intercept trap in sandy barrens / Mycterus scaber Haldeman det. J. P. Gruber 2010 / [lge. blue label] PARATYPE ♂ Mycterus youngi Pollock ” . 1 ♂ ( CMNH), labeled: “L.S [= Lake Superior ?] / [square blue-green label] Henry Ulke Beetle Coll. CMNH Acc. No. 1645 / Mycterus concolor Lec / [lge. blue label] PARA- TYPE ♂ Mycterus youngi Pollock ” . 1 ♀ ( CMNH), labeled: “L.S [= Lake Superior ?] / 29 / [square bluegreen label] Henry Ulke Beetle Coll. CMNH Acc. No. 1645 / [lge. blue label] PARATYPE ♀ Mycterus youngi Pollock ” .

Etymology. I take pleasure in naming this new species after my friend, colleague, and fellow practitioner in “LBBs” Daniel K. Young (University of Wisconsin, Madison). I have benefited greatly from our past collaborations and his generous offerings of advice and specimens.

Diagnosis and Recognition. Mycterus youngi is similar to M. marmoratus ; both species have a brown color, indistinctly modified male antennomeres, and apically rounded parameres on the male genitalia. However, the vestiture color is different between the two species. On the elytra of M. youngi , the setae are unicolorous ( Fig. 1 ), while on those of M. marmoratus , the setae are of two colors, with patches of silver setae contrasting with the brown elytral color ( Fig. 2 ). This difference is consistent among the two known specimens of M. marmoratus and nine of M. youngi . The lateral margins of the pronotum are different, with the sides of M. marmoratus ( Fig. 2 ) more sinuate compared to M. youngi ( Fig. 1 ). The male sex patch is more extensive in M. youngi , occupying the entire length of the first ventrite ( Fig. 4 ); in M. marmoratus , the patch does not extend to the anterior margin of the ventrite, and is comparatively narrower. Despite these differences, the shape of the male parameres is similar between the two species; the only two North American species with distally broadly rounded parameres are M. youngi ( Fig. 5 ) and M. marmoratus (see Pollock 1993, fig. 8), an indication perhaps of their close relationship.

Description. With general features of Mycterus and subgenus Mycterinus Seidlitz sensu Spilman (1951) (e.g., rostrum with dorsal surface flat or concave in lateral view; frons with supra-antennal margins straight or only weakly raised; pronotum cribrately punctured, trapezoidal or campanulate in dorsal view, disc evenly convex; elytra cribrately punctuate, sides arcuate) with the following details: Size: TL = 6.9–8.6 mm, average = 7.9 mm (males), 7.8–10.7 mm, average = 8.7 mm (females); GEW = 2.5–3.3 mm (males), 2.9–4.1 mm (females). Color: Entire body red-brown to brown ( Fig. 1 ); head and pronotum somewhat darker than elytra in most specimens; in most specimens, elytral humeri somewhat lighter in color than disc; elytral setae not forming patches of contrasting color. Legs somewhat lighter in color than venter. Sexually dimorphic. Males smaller than females, with sex patch on ventrite 1; sex patch ( Fig. 4 ) large, occupying entire length of ventrite, not raised above level of ventrite ( Fig. 3 ), surface smooth, asetose, with fine punctulae; male and female antennomeres similar in structure, subserrate ( Fig. 3 ), antennomeres longer than wide. Measurements (in mm): HL = 1.2–1.9; PL = 1.3–2.1; EL = 4.4–6.7; GHW = 1.1–1.5; GPW = 1.8–2.9; GEW = 2.5–4.1; GPW/PL = 1.31–1.38; TL/GEW = 2.61–3.00. Male genitalia ( Fig. 5 ): Basal piece much longer than length of parameres, ratio = 1.8:1; median lobe slightly shorter than tegmen, evenly tapered distally, apex appearing sharply pointed dorsoventrally, appearing blunt in lateral view; parameres rounded distally, inner margins with deep ventral incisions near apices. Female genitalia: Not examined.

Natural History. The only data available are associated with labels on the few known specimens. One paratype has the label “L.T.”, which is here inferred to mean “light trap” (there are a few moth scales on some of the specimens). Another label, on the only recently collected specimen, indicates that the individual was taken in a “flight intercept trap in sandy barrens”. Individuals of most species of Mycterus are usually found at flowers ( Pollock 2002); it is probable that adults of M. youngi exhibit this same behavior.

Distribution. ( Fig. 6 ). It is somewhat surprising that the nine known specimens of this species have all been collected in Wisconsin in Iowa and Wood counties ( Fig. 6 ). Seven of the specimens have precise label data; two others are labeled “L.S” only. The two localities in Wood County are very near one another, across the Lower Wisconsin River.

Figures

Figs. 1–5. Mycterus spp. 1) M. youngi, male paratype, dorsal habitus, TL = 8.6 mm; 2) M. marmoratus, male holotype, dorsal habitus, TL = 6.5 mm; 3) M. youngi, male holotype, lateral habitus; 4) M. youngi, detail of male sex patch; 5) M. youngi, male genitalia, scale bar = 0.25 mm.

Fig. 6. Map of the known distribution of Mycterus youngi, by county (left) and actual localities in Wisconsin (right). The two paratypes labeled “L.S” are not mapped.