Psallus (Phylidea) yongdaeri Duwal

Duwal, Ram Keshari & Lee, Seunghwan, 2015, Additional descriptions of the plant bug genus Psallus from the Korean Peninsula (Hemiptera: Heteroptera: Miridae: Phylinae), Zootaxa 3926 (4), pp. 585-594 : 591-593

Psallus (Phylidea) yongdaeri Duwal sp. nov.

Figures: 1F −G, 2D −G, 4B, 5B

Diagnosis. Recognized by the small and ovoid body, black or blackish brown dorsum, often dull with greyish posterior margin of vertex and brownish margin of exo- and endocorium, pale (or yellowish pale brown) antennae with fuscous ring at the base of segment I, fuscous or black metafemora without spots, pale pro- and meso-tibiae with large castaneous spots on basal half region and meta-tibiae with brown spots at bases of black spines ( Fig. 1 F −G), C-shaped endosoma with distinctly featured apical process ( Fig. 2 D).

Description. Male. Body small and oval. COLORATION ( Fig. 1 F −G): Head black except for greyish posterior margin of vertex; antennal segments pale with extreme base of segment I dark and furnished with a pair of brown spine like setae, and segment IV slightly darker; labium brown with darker base. Pronotum, meso-scutum and scutellum black except for brown lateral and posterior corners of the meso-scutum and the scutellum; hemelytron blackish brown on large posterior region (on dark brown specimen) or margin of endo- and exocorium dark brown (in black specimens), membrane dark grey. Venter black or dark brown, ostiolar peritreme black. Coxae and trochanters black; pro- and mesofemora darker with pale apices; metafemora black (in black specimens) or dark brown (in dark brown specimens) and without darker spots; tibiae pale, basal half of pro-and meso-tibiae with large castaneous spots at bases of black spines and entire metatibiae with large brown spots at bases of black spines. Abdomen black or dark brown in color. SURFACE AND VESTITURE: Head, pronotum, meso-scutum and scutellum dull (or shagreened) with uniformly distributed pale simple reclining setae and moderately flattened sericeous appressed setae; hemelytron somewhat polished, with uniformly distributed black semi-erect setae and sericeous appressed setae. STRUCTURE: Head width across eyes sub-equal to mesal length of pronotum, vertex width sub-equal to length of tarsus; antennal segment II comparatively short and thick; interocular space wide; labium reaching apex of metacoxae. Thorax slightly convex, with semi-circular postero-lateral margin. GENITALIA ( Figs. 2 D −G, 4B): Endosoma: C −shaped with several short or long lateral processes, membranous structure at base of apical processes furnished with spinules; and secondary gonopore subapical in position ( Figs. 2 D, 4B). Left paramere: Body short, anterior process slender and elongated, and posterior process short and blunt ( Fig. 2 E). Right paramere: Simple leaf-like apically tapering with short outgrowth ( Fig. 2 F). Phallotheca: Narrow, with hooked sub-apical process ( Fig. 2 G).

Female. Similar to color and texture as males, only having slightly larger body width. GENITALIA ( Fig. 5 B): Sclerotized rings somewhat broad, anteriorly oval and posteriorly un-curved or flatten margin.

Measurements. (♂/♀) (n=5/4). Body length 2.98−3.20/ 3.06−3.23; length from apex of tylus to cuneal fracture 2.31−2.40/ 2.31−2.46, width of head across eyes 0.72−0.77/ 0.74−0.79; width of vertex 0.37−0.43/ 0.37−0.40, lengths of antennal segments 0.21−0.23, 0.83−0.90, 0.50−0.54, 0.32−0.38/ 0.20−0.23, 0.82−0.91, 0.46−0.54, 0.31−0.35; mesal length of pronotum 0.64−0.73/ 0.63−0.71; basal width of pronotum 1.24−1.34/ 1.30−1.33; maximum width across hemelytron 1.53−1.66/ 1.58−1.68; and lengths of metafemora, tibiae and tarsus 1.05−1.19, 1.71−1.80, 0.41−0.51/ 1.12−1.18, 1.65−1.74, 0.42−0.46.

Etymology. Named for the type locality, Yongdae-ri; a noun in apposition.

Distribution. Korea (South*).

Specimen examined. Holotype. ♂, South Korea, Gangwon-do, Inje-gun, Buk-myeon, Yongdae-ri, Mt. Maebong, Yongdae Natural Recreation Center, on Ulmaceae , 20.vi.2013, R.K. Duwal (SNU). Paratypes. South Korea: 5♂, 2♀, same data as for holotype; 1♀, same data as for holotype except collected on Artemisia sp. ( Asteraceae ); 1♂, 1♀, same collection site as for holotype, on light trap, 19.vi.2013.

Remarks. This new species is placed in the subgenus Phylidea , based upon the overall appearance of its endosoma being similar to those of congeners, i.e. unique serrated spinules on the lateral margin of the apical region.

Psallus yongdaeri is morphologically close to Psallus castaneae in color and vestiture but can be easily separated by the distinct basal ring on antennal segment I, longer apical process of endosoma, and arrangements of lateral processes ( Fig. 2 D).

A few specimens of Psallus yongdaeri were collected on unidentified Ulmaceae tree during spring flowering season in South Korea. In addition, some specimens were collected in light trap and also on Artemisia sp. under the tree where siblings were collected. However, we are not sure of host plant, as we were unable to observe any nymphs during collection time.

Figures

FIGURE 1. Habitus images of Psallus spp. A − B. P. sanguinarius; C. P. injensis; D − E. P. taehwana; F − G. P. yongdaeri.

FIGURE 2. Male genitalia of Psallus spp. A − C. P. injensis; D − G. P. yongdaeri. A, D. Endosoma; B, E. Left paramere. F. Right paramere. C, G. Phallotheca. Scale bars: 0.05 mm.

FIGURE 5. Images of female genital structure: Bursa copulatrix. A. Psallus taehwana; B. P. yongdaeri.