Eremophylus nakagawai n. sp.

(Figs. 1 A−E; 2C−I; 3B, D; 4B−D; 16; 18H−O; 19I−P)

Material examined. Holotype (♂). JAPAN: Honshu, Akita Pref., Yurihonjo City, Mt. Chokai, Chokai Town, Sarukura, 39.17 140.14, 610 m alt., on Phellodendron amurense Rupr., 13 Jun 2019, Y. Nakagawa (AMNH) (AMNH _ PBI 00380697) . Paratypes: JAPAN: Same data as for holotype 5♂ (TYCN); same data, except for date, 27 Jun 2017, 3♂ 4♀ & 26 Jun 2018, 1♀ (CNC, TYCN) .

Diagnosis. Easily distinguished from the other congener, E. hirtus, by the following characters: Antennal segment II almost entirely pale; metafemur as long as or shorter than antennal segment II; and metatibia yellowish brown. The final instar nymph is recognized by its pale green, elongate-ovoid body; uniformly distributed, dark spines on dorsum; and small dark spots on head, antennae, thorax, and legs (Fig. 1E).

Description. General coloration not sexually dimorphic, but female has slightly larger size, wider vertex, and shorter antennal segment II (Table 1) as in many other mirids. Body elongate, medium-sized; basic coloration variable, usually dark brown, but widely smoky yellow in pale variant (cf. Fig. 2H–I); dorsal surface usually dark brown except for inner margin of corium and cuneal margin (Fig. 1C–D), matte, with densely distributed, brown, simple setae and silvery, lanceolate setae (Fig. 18I–J). Head dark brown, partly or widely smoky yellow; eyes small; vertex wide, about twice as wide as an eye in dorsal view. Antenna yellowish brown; each segment generally linear; segment I dark brown; extreme bases of segments II and III infuscate; combined length of segments III+IV slightly longer than II. Labium shiny yellowish brown; its length shorter than antennal segment II; its apex not exceeding middle of mesocoxa (Fig. 18H, K); apical 1/3 of segment IV darkened; sensilla on labial apex as in Fig. 18L. Pronotum weakly shining, somewhat shagreened, varying from smoky yellow (Fig. 2H) to dark brown (Fig. 2C, F); calli weakly elevated; mesoscutum, scutellum and thoracic pleura including scent efferent system varying from yellowish brown to fuscous; scutellum (if darkened) with a mesal pale stripe (Fig. 1C–D); peritreme of scent efferent system small (Fig. 18M). Hemelytron variable in color; inner margin of corium and margins of cuneus always pale; membrane smoky brown, with pale median part and veins. Coxae varying from smoky yellow (Fig. 2I) to dark brown (Fig. 2G); legs yellowish brown, variable in color; profemur spotted apically, sometimes with darkened base; metafemur widely darkened (Fig. 2D, G) or with 3 rows of dark spots ventrally (Fig. 2E, I), about as long as or shorter than antennal segment II; each tibia with dark spots at bases of spines; apical part of each tarsomere III dark brown; meta-tarsomere II slightly longer than III (Fig. 18N); claw thick, with relatively developed pulvilli (Fig. 18O). Abdomen varying from pale to fuscous. Male genitalia (Figs. 4 B−D; 19I−L): Pygophore with a ventral mesal keel at apical 1/3; phallotheca stout (Fig. 19J); right paramere about twice as large as left; (Fig. 4C–D); vesica not inflated at middle (Fig. 19I), with sharp subapical branch (Fig. 19L). Female genitalia (Figs. 3B, D; 19 M−P): Sclerotized rings thick-rimmed, elongate-oval (Figs. 3D, 19N); posterior wall relatively smooth (Fig. 19O), with interramal sclerite sparsely spinulate (Fig. 19P); ovipositor (gonapophysis) I expanded subapically (Fig. 3D).

Measurements: See Table 1.

Etymology. Named for Mr. Y. Nakagawa (Akita, Japan) who enthusiastically collected the specimens of this new species, observed its ecology, and shared the images.

Biology. Nakagawa (pers. obs.) verified the host association of Eremophylus nakagawai with inflorescence of Phellodendron amurense Rupr. (Rutaceae) (Fig. 1A–B), on which both the adults and late instar immature forms were found together (Fig. 1E). A univoltine life cycle is assumed for this new species. The adults appear in mid to late June.

Remarks. A ‘horn-like sclerite’ on the female seminal depository (‘bv’ in Figs. 3B, 19M) was not regarded as a unique character but simply a fragment of apical part of the vesica (endosoma) after dissecting two additional female specimens. It was presumed to be ‘accidentally broken off’ during copulation and left in the female genital chamber, which may represent an unprecedented case.