Melaleucacoris, 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 : 78-80

Melaleucacoris , new genus

TYPE SPECIES: Melaleucacoris glomeratae , new species.

DIAGNOSIS: Recognized among Australian phyline taxa by pale general coloration with reddish spots and patches, sericeous silvery setae, posteromedial tubercle of left paramere, secondary gonopore located at midpoint of endosoma, dorsal endosomal spine membranous, inflated, and microspiculate at base and serrate on anterior edge of apex, ventral apical endosomal spine long, strongly serrate, and absence of process arising close to secondary gonopore; posterior wall of female genitalia divided with strong longitudinal fold and posteromedial projection abutting ovipositor bulb and vestibular sclerites thick, well sclerotized, and triangular.

DESCRIPTION: MALE: Macropterous, total length 2.35–2.51, pronotum width 0.86–0.88. COLORATION (pl. 5): Dirty pale or faintly rusty cream base color with contrasting reddish mahogany color in discreet spots, blotchy and coagulated patches, and unbroken regions distally on corium including costal margin and apex of cuneus; hemelytral membrane uniformly fuscous; antennal segment 1 with discrete dark blotch, antennal segments 3 and 4 somewhat darkened; apical portion of labium dark brown; legs predominately pale with dark spots on apices of femora; metafemora with solid dark markings on dorsal margin blending into ragged stripes distally; thoracic venter, including metepisternal scent auricle, with large dark mahogany regions, abdominal sterna with irregular dark color; tibiae with large black spots; claws dark brown. SUR- FACE AND VESTITURE (pl. 5): Dorsum very weakly shining; dorsal vestiture with relatively dense, sericeous, shining, silvery setae; black setae absent; tibiae with black spines. STRUC- TURE: Head: Relatively narrow, posterior margin of eyes slightly separated from anterior margin of pronotum, eyes medium sized in dorsal view, just reaching to level of antennal insertion in lateral view, weakly emarginate near fossa. Antenna: Segment 2 of greatest diameter at apex, tapering to base, length approximately equal to 80% of pronotal width. Labium: Reaching apex of metacoxa. Thorax: Pronotum: Subquadrate, lateral margins gently curved, calli faintly demarcated, posterior lobe flat, posterior margin straight; mesoscutum moderately exposed. Pretarsus: Claws small, gently curved; parempodia short setiform; pulvilli moderately short, located within and proximad of angle of claw (fig. 18A). Hemelytron: Costal margin weakly curved. GENITALIA (pl. 30A–G): Pygophore: Medium sized, conical; paramere insertions without tubercles or discrete patches of bristles. Endosoma: With one strap, J-shaped, without torsion; endosoma thickest at midpoint; endosomal strap sclerotized beyond secondary gonopore extending to apex of dorsal spine; base of dorsal spine with inflated microspiculate membrane and moderately long, narrow accessory spine, apical region of dorsal spine with serrate margin on anterior edge; long marginally serrate ventral spine emanating at level of insertion of dorsal spine. Secondary gonopore: Well formed, located just proximal to midpoint of endosoma. Phallotheca: Relatively short and flat; apex slightly rounded; aperture small, occupying posterodistal surface of phallotheca; right side of anterior surface with long spine, almost reaching apex of phallotheca. Parameres: Left paramere: Dorsal tubercle on anterolateral margin near base of posterior process, length of tubercle equal to length of posterior process; posterior process short strongly bent ventrad, apex rounded. Right paramere: Short, broad, with moderately long acuminate apex.

FEMALE (pl. 5): Coloration and structure similar to male, except body slightly wider, antennal segment 2 more slender and tapering proximally in contrast to male; total length 2.51–2.70, pro- notum width 0.87–0.94. GENITALIA (pl. 30H– M): Posterior margin of sternite 7: Medial shield-shaped projection. Vestibular sclerites: Moderate in size, strongly sclerotized, triangular, not projecting beyond anterior edge of dorsal labiate plate. First gonapophyses: Asymmetrical, well sclerotized; right side triangular, larger than left, left side quadrate. Ventral labiate plate: Symmetrical, well sclerotized, triangular, right and left sides meeting on linear surface. Dorsal labiate plate: Medium sized, subquadrate, convex longitudinally. Sclerotized rings: Medium sized, symmetrical, separated by width of ring, subrectangular, relatively thick walled. Posteromedial region: Weakly sclerotized paramedially, midline with posterior projection; surface smooth not particularly sunken. Anterolateral region: Microspiculate, greatly projecting anteriad of sclerotized rings. Intersegmental membrane: Undifferentiated, merely folded. Posterior wall: Well sclerotized and divided on midline with strong longitudinal fold; each half of dorsoanterior surface rounded proximally and at lateral margin, tumid, microspiculate bulging anteriorly into genital chamber; posteromedial surface with solid, strongly sclerotized process projecting posteriad and abutting ovipositor bulb. Interramal sclerites: Well sclerotized, bat shaped with paramedial notches. Interramal lobes: Microspiculate, tumid, situated at lateral margins.

ETYMOLOGY: A combination of the generic name Melaleuca and the Greek word coris, “bug”; masculine.

DISCUSSION: The strongly spotted coloration of the single described species of this taxon suggests an association with species of Ancoraphylus of the Leptidolon group of genera ( Weirauch, 2007). Even though the structure of the male and female genitalia of the new species clearly indicates placement in the Exocarpocorina , a number of characters argue against placement in Ancoraphylus . We therefore propose a new genus to accommodate the unique features of this taxon. The endosoma does not have a process arising near the secondary gonopore and the apical region is more or less membranous; the posteromedial portion of the middle dorsal labiate plate is weakly sclerotized and not microspiculate, and the posterior wall has a prominent well-sclerotized posterior projection abutting the ovipositor bulb.

An additional species of Melaleucacoris from Western Australia, taken on Calothamnus quadrifidus R. Br. ex W.T. Aiton ( Myrtaceae : Melaleuceae ), was recognized by us based on its unique endosoma, dorsoposterior surface of posterior wall, and conspurcate hemelytral membrane. Unfortunately, the male is lost and we refrain from describing the potential new species based on the two available female specimens.

The current sole member of Melaleucacoris is seemingly distributed only in the arid center of Australia, a distribution shared with two other new species ( Melaleucaphylus glomeratae , Xiphoides anangu ) treated herein (table 4). Other Heteroptera known from only the desertic region of the Northern Territory are seven species of Cremnorrhinina ( Schuh and Schwartz, 2016) , among orthotyline plant bugs Acaciacapsus amadeus ( Cassis and Symonds, 2014) , one species of callitroid-inhabiting Orthotylini ( Symonds and Cassis, 2018) , and three species of the Lattinova complex of genera (Cassis, 2008). Seven species of lace bugs ( Cassis and Symonds, 2008; Cassis and Symonds, 2011; Cassis et al., 2017) are also uniquely known from central Northern Territory. However, the distribution of many more heteropteran species taken in central Northern Territory also extend to other arid regions of Australia, especially southwestern Western Australia; with more exploration Melaleucacoris could exhibit this wider geographic pattern.