Plagiotylus, SCOTT, 1874

Tatarnic, Nikolai J. & Cassis, Gerasimos, 2012, The Halticini of the world (Insecta: Heteroptera: Miridae: Orthotylinae): generic reclassification, phylogeny, and host plant associations, Zoological Journal of the Linnean Society 164 (3), pp. 558-658 : 630-633

PLAGIOTYLUS SCOTT ( FIGS 4 , 50–51 )

Plagiotylus Scott, 1874: 272 (gen. nov. type species: Plagiotylus maculatus Scott, 1874 by monotypy); Atkinson, 1890: 125 (cat.); Reuter, 1891: 98, 160 (descr., key); Hueber, 1906: 5 (key); Kirkaldy, 1906: 131 (cat.); Oshanin, 1910: 783 (cat.); Reuter, 1910: 148 (cat.); Stichel, 1933: 235 (key); Carvalho, 1952: 74 (cat.); Carvalho, 1955: 67 (key); Carvalho, 1958: 30 (cat.); Wagner & Weber, 1964: 285 (descr., key); Wagner, 1973: 100 (descr., key); Schuh, 1995: 69 (world cat.).

Diagnosis: This genus is distinguished from all other Halticini by the following combination of characters: glossy surface; uniform pale green and yellow coloration; MTG obsolete; females with coleopteroid hemelytra.

Redescription: Coloration ( Fig. 4 ): mostly pale green, with yellow, brown, or black markings. Head, pronotum, and scutellum sometimes with blackish markings, antennae often with some brown or black apically, hemelytra sometimes reddened, legs generally pale. Surface and vestiture ( Figs 4 , 50A–F ): body shining and impunctate. Body clothed in long, dark simple setae ( Plagiotylus dispar with both dark and pale setae); antennae and legs spinose, spines longest on AI and tibiae. Structure: male elongate and macropterous, female oval, coleopteroid. Head ( Figs 4 , 50A–C ): transverse, slightly broader than anterior margin of pronotum; approximately as tall as broad, genae height greater than eye height; posterior margin of vertex straight, weakly dorsally rounded; vertex with shallow, narrow, transverse depression, posterior margin weakly upturned and carinate; frons broadly medially rounded, sulcate at clypeus. Labium ( Fig. 50A, C ): LI short and thick; generally reaching meso- or metacoxae. Antennae ( Figs 4 , 50A–C ): adjacent to lower margin of eye; always shorter than body, shortest in female; AI slightly swollen, almost twice length of eye height. Thorax ( Figs 4 , 50A–D ): pronotum trapezoidal and sloping in males, shorter, subrectangular and flat in females, collar present in males, thin and flat; callosite region weakly defined, lateral margins sloping, posterior margin straight to weakly medially concave; mesoscutum visible in both sexes; metathoracic spiracle elongate-oval, without evaporative bodies; MTG obsolete. Hemelytra ( Figs 4 , 50A ): macropterous male – elongate, lateral margins subparallel to apex of cuneus; clavus apically expanding; embolium narrow, R + M vein running nearly to cuneus; cuneus elongate and narrow; membrane with two cells. Coleopteroid female – clavus and R + M vein faint, cuneus and membrane absent. Legs ( Figs 4 , 50E ): slightly longer in males; metafemora somewhat swollen in females; pretarsi without fleshy pulvilli. Abdomen ( Figs 4 , 50A ): male: elongate, parallel-sided to pygophore. Female: broadly elongate-oval. Male genitalia ( Figs 50A, F , 51A–D ): pygophore conical, genital opening large; phallotheca broad, apically tapered, with small lateral flanges, apicodorsally sulcate and weakly sclerotized; left paramere shorter than right, L-shaped, with broad sensory lobe and narrow apical apophysis, apex typically weakly hooked; right paramere much longer than left, apical club weakly laterally deflected, narrow, weakly concave, tapered at apex; ductus seminis short, thick, with flexible ribbing; secondary gonopore elongate and scoop-shaped with prised operculum, opens ventrally, apically dorsoventrally compressed, with distinct scale-like texture; endosoma simple, without spicules, in P. maculatus (and possibly others) with weakly sclerotized fields of spines. Female genitalia ( Fig. 51E, F ): sclerotized rings ovate, transverse, subcontiguous, weakly sclerotized, most strongly sclerotized laterally, less so towards midline, lateral margins and adjacent portion of DLP strongly upturned; lateral upturned margins of DLP strongly sclerotized; lateral-most region of VLP joins with rami to form paired, medially projecting, sclerotized processes; posterior wall mostly membranous, with weakly sclerotized, transverse, M-shaped process; opening to vestibulum symmetrical, lateral margins weakly swollen and weakly sclerotized.

Diversity and distribution: Plagiotylus includes six species, all restricted to the Mediterranean region.

Included species: Plagiotylus bolivari ( Reuter, 1880) Spain

Plagiotylus dispar Reuter, 1899 * Syria; Israel

Plagiotylus maculatus Scott, 1874 * Spain

Plagiotylus ruffoi Tamanini, 1960 Italy

Plagiotylus sahlbergi Reuter, 1901 Algeria; Greece; Libya; Tunisia

Plagiotylus zorzii Tamanini, 1955 Italy

Biology and host plant associations: The limited biology and host information available for Plagiotylus comes primarily from Wagner (1973). Plagiotylus maculatus is said to prefer dry, sunny areas and is found on Teucrium chamaedry s ( Lamiaceae ). This species has a single generation per year, overwinters as eggs, with adults present in June and July. Plagiotylus ruffoi has been collected at high altitude (1200–1890 m) in Sicily, on Astragalus siculus nebrodensis (Fabaceae) , with adults are present in July. Tamanini (1960) also reports this species on an unidentified species of Prangos (Apiaceae) ( Table 1).

Remarks: This redescription is based on examination of P. dispar and P. maculatus , as well as the literature. Wagner (1973) provided descriptions, illustrations, and a key to all species; however only the parameres and aedeagus of Plagiotylus sahlbergi are illustrated.

The relative placement of Plagiotylus differs between our equal weights and implied weights analyses, and its true relationship within the Halticini remains uncertain.

Figures

Figure 4. Photographs of Halticini genera: Labops–Strongylocoris. Abbreviations: F, female; M, male.

Figure 50. Scanning electron micrograph images of Plagiotylus maculatus (male). A, lateral view; B, head and thorax, anterodorsal view; C, head and prothorax, lateral view; D, meso- and metathorax, lateral view; E, tarsus; F, pygophore, lateral view (note: most setae missing from specimen).

Figure 51. Male and female genitalia of Plagiotylus maculatus. A, aedeagus; B, secondary gonopore; C, left paramere; D, right paramere; E, bursa copulatrix; F, first gonapophyses, ventral view; G, posterior wall.