Leptospermia, Schwartz & Weirauch & Schuh, 2018

Schwartz, Michael D., Weirauch, Christiane & Schuh, Randall T., 2018, New Genera And Species Of Myrtaceae-Feeding Phylinae From Australia, And The Description Of A New Species Of Restiophylus (Insecta: Heteroptera: Miridae) Michael D. Schwartz Christiane Weirauch, Bulletin of the American Museum of Natural History 2018 (424), pp. 1-161 : 72-74

Leptospermia , new genus

TYPE SPECIES: Leptospermia cassisi , new species.

DIAGNOSIS: Shares some features of male and female genitalia, especially coiled endosoma, long apical portion of right paramere, large coiled vestibular sclerites, and simple membranous posterior wall and adjacent intersegmental region with genera of the Xiphoides clade of Exocarpocorina ( Weirauch and Schuh, 2011 ). Distinguished from these taxa (Arucanophylus, Xiphoidellus , Xiphoides ) by mostly uniform pale yellowish green coloration, black simple setae on dorsum; black tibial spines without dark basal spots, long straight setiform parempodia, absence of pulvilli, much larger endosoma with larger secondary gonopore, and paired lateral interramal sclerites without sclerotization on dorsoposterior margin.

DESCRIPTION: MALE: Macropterous, total length 3.49–4.35, pronotum width 1.14–1.35. COLORATION (pls. 4, 5): Uniformly dull yellowish to grayish tan with darker orange tan on head, except near eyes and sometimes on mandibular plate, mesoscutum, scutellum, cuneus, and mesosternum; sometimes frons dark gray; black on distal portion of, or entire clypeus, antennal segment 1, segments 3 and 4 of labium, tarsal segments, claws, and phallotheca; remain- der of antenna and tibiae tan or pale brown; tibiae without dark spots at base of black spines; hemelytral membrane slightly fumose. SUR- FACE AND VESTITURE: Dorsum weakly shin- ing; vestiture with moderately dense, dark, suberect, simple setae and posterior margin of pronotum and mesoscutum with sericeous, suberect, silvery setae; entire ventral surface with pale suberect simple setae (fig. 16B). STRUC- TURE: Head: Medium sized, posterior margin of eyes contiguous with anterior margin of pronotum, eyes medium sized in dorsal view, occupying 80% of height of head and surpassing antennal insertion by width of fossa in lateral view; eyes broadly emarginate near fossa (figs. 16A, 17A). Antenna: Segment 2 of practically uniform diameter, length approximately equal to 80% of pronotal width. Labium: Length variable. Thorax: Pronotum: Subrectangular, lateral margins straight, calli faintly demarcated, posterior lobe flat, posterior margin straight; mesoscutum broadly exposed; metathoracic spiracle and scent-gland system typically phyline (figs. 16C, 17B). Pretarsus: Claws moderately long, gently curved; parempodia straight, length from moderately to relatively long, setiform; pulvilli with moderate size and height, situated on claw base proximad of angle (figs. 16D, 17D). Hemelytron: Costal margin slightly convex. GENITALIA (figs. 16E, 17C, pls. 28, 29A–J): Pygophore: Large, broadly conical in dorsal view, laterally compressed, forming keellike caudal surface, perpendicular to aperture in lateral view; left margin of aperture with small elongate patch of short bristles. Endosoma: Forming a complete coil, with two confluent straps, ventral strap terminating just distad of distal margin of secondary gonopore; dorsal strap surpassing gonopore by slightly more than 3× gonopore, terminating in narrow apex; subapical region between apex and secondary gonopore slightly widened with undulating ventral margin or with delicate, weakly sclerotized, ventrally directed process at distal edge of secondary gonopore. Secondary gonopore: Subapical, well formed; orientation of aperture ventrad or laterad; conspicuous gonopore sclerite on proximal margin. Phallotheca: Elongate, basal region of uniform width, gradually narrowed toward apex, aperture on anterior surface, slitlike, uniformly narrow; sometimes apical region with posterior edge wider than anterior edge, right lateral surface at about midpoint with sclerotized strut extending to middle of basal region; basal region strongly sclerotized on surface adhering pygophore. Parameres: Left paramere: Body elongate, region between anterior and posterior processes extending posteriad; posterior process moderately long, straight, broad basally, apex narrowly rounded; anterior process shorter than posterior process, projecting slightly dorsad, broad basally, rounded in cross section; apex rounded or sharp and bent toward middle of paramere. Right paramere: Large, subrectangular, apical one-third directed ventrad; apex variable—conspicuously narrow, short, and pointed or long and gently attenuate.

FEMALE (pls. 4, 5): Coloration and structure similar to male, except costal margin slightly more convex than in male; antennal segment 2 more slender and tapering proximally in contrast to male; total length 3.20–4.00, pronotum width 1.08–1.29. GENITALIA (pl. 29K–N): Posterior margin of sternite 7: With triangular medial projection. Vestibular sclerites: Large, strongly coiled, relatively weakly sclerotized, with large loop on right side, greatly projecting beyond anterior edge of dorsal labiate plate. First gonapophyses: Medium sized, in form of basal quadrate blocks. Ventral labiate plate: Medium sized, moderately sclerotized, convoluted, paramedial anteroventral extension very large and modified, projecting from right side, right side flattened and covering anterior surface of basal structures. Dorsal labiate plate: Large, shield shaped with undulate anterior and lateral margins, long and concave longitudinally; ventral surface with relatively large spicules. Sclerotized rings: Moderately large, teardrop shaped, medial margin wider than lateral attenuate auricleshaped lateral margin, thick walled. Posteromedial region: Entire medial plate concave or sunken ventrad of lateral oviducts and spermathecal gland, plate not apparently microspiculate. Anterolateral region: Extending anteriad of sclerotized rings, surface microspiculate ventrad of rings. Intersegmental membrane: Weakly sclero- tized, fringelike, serrate, transverse band spanning genital chamber, weakly projecting into genital chamber. Posterior wall: Dorsoposterior margin of wall entire, smooth, shallowly concave into genital chamber anteriad. Interramal sclerites: Pair of well-sclerotized, elongate plates forming ventrolateral margin of wall; dorsal region wide, weakly sclerotized, spanning interramal area, base of sclerite notched. Interramal lobes: Membranous, without microspicules.

ETYMOLOGY: Named after the host-plant genus Leptospermum ; feminine.

DISCUSSION: Leptospermia is one of several exocarpocorine taxa of nearly uniform yellow/ green coloration (in preserved specimens) with at least some dark recumbent simple setae on the dorsum, all of which feed on a variety of genera of Myrtaceae . These include several species of Melaleucoides and Scholtzicoris linnavuorii . However, the setiform parempodia and simple posterior wall indicate that Leptospermia is not a member of the Melaleucoides group ( Harpagophylus , Melaleucoides , Thryptomenomiris ) of Exocarpocorina ( Schuh and Weirauch, 2010). In body size and form Leptospermia resembles many species of Wallabicoris , but no species in that genus has the yellow/green coloration of Leptospermia , never feeds on the Myrtaceae , and each has its own distinctive features in the endosoma, even though it is long and forms a single coil in both genera.

Within the Exocarpocorina a relationship to Xiphodellus is suggested by the deep posterior aspect of the pygophore, elongate or deep dimension to the left paramere, and elongate apical portion of the right paramere. Leptospermia anatoles also possesses an accessory spine projecting from the distal margin of secondary gonopore as in Xiphodellus. Additionally, the relatively simple, undivided posterior wall and adjacent intersegmental region and the large, strongly coiled vestibular sclerites in the female indicate a relationship between Arucanophylus, Leptospermia, Xiphodellus , and Xiphoides . A number of Xiphoidellus spp. have Myrtaceae hosts.

We have examined specimens (63, 3♀) taken at 20 km E of Retreat (W. of Uralla), New South Wales, on Leptospermum brevipes we place in Leptospermia based on preparations of teneral endosomae; however, assigning them to either of our new species is problematic. These specimens have a smaller, generally slightly orange-tinged body with reddish costal margin and cuneus and dusky brown collum, clypeus, labrum, antennal segment 1, and apices of hind femora. Description of this potential new taxon awaits examination of males with fully developed endosomae.

As currently understood the genus Leptospermia is distributed across the Nullarbor Plain of southern Australia with its two distinct species restricted to Western Australia or New South Wales plus South Australia (table 4). All 10 species of the known myrtaceous host plants utilized by Leptospermia spp. belong to the tribes Chamelaucieae and Leptospermeae . Almost all specimens of Leptospermia (90%) were taken on Leptospermeae hosts. All individuals taken in New South Wales and South Australia ( L. anatoles ) were found on two species of Leptospermum . Only specimens from Western Australia were found on Chamelaucieae host plants (tables 2, 3).