Niesthrea Spinola, 1837

Melo, María Cecilia & Henry, Thomas J., 2019, Revision of the New World Scentless Plant Bug Genus Niesthrea (Hemiptera: Heteroptera: Rhopalidae), with Descriptions of Six New Species and a Key to the Species, Insect Systematics and Diversity 3 (5), No. 9, pp. 1-36 : 2

Niesthrea Spinola, 1837

(urn:lsid: Coreoidea .speciesfile.org:TaxonName:452477)

Coryna Wolff, 1811 : iv (original description). Type species: Lygaeus sidae Fabricius, 1794 . Preoccupied by Coryna Bosc, 1802 (Coelenterata) .

Corizus (Niesthrea) Spinola, 1837: 245 (original description); Stål, 1870: 223 (diagnosis); Berg, 1878: 186 (list of species); Van Duzee, 1916: 15 (checklist), 1917: 123 (catalog); Torre-Bueno, 1941a: 286 (keys), 1941b: 95 (keys). Type species: Lygaeus sidae Fabricius, 1794 . Monotypic.

Niesthrea: Baker, 1908: 243 (revised status); Harris, 1943: 201 (generic status); Chopra, 1967: 370 (description, key), 1973: 443 (description); Göllner-Scheiding, 1983: 52 (catalog); Henry, 1988: 659 (catalog); Froeschner, 1989: 611 (list); CoreoideaSF Team, 2018 (online catalog).

Type species. Lygaeus sidae Fabricius, 1794 .

Diagnosis

Niesthrea ( Fig. 1) is best distinguished from all other New Word genera by a combination of the lateral margin of the pronotum lacking a notch behind the collar; the slender, mutic, hind femora that are subequal to the diameter of the front and middle femora; the pronotum without a delimited collar; the surface between the anterior pronotal margin and calli distinctly punctate; the labium extending beyond the hind coxae to the posterior margin of abdominal segment II or beyond; and the structure of the male genitalia. The male genital capsule ( Fig. 2 ) has an elevated, variably shaped, median lobe; a lateral lobe ranging from slender and apically acute to wide at the base and broadly rounded apically; and the parameres varying in shape from vertical and slender to rounded, triangular, or broadly transverse. In addition, species of Niesthrea have a uniquely shaped head that is only slightly broader than long, with a median groove on the frons; the ocelli are closer to the compound eyes than to each other; and the femora and tibiae usually have large, dark, coalescing spots and bands.

Niesthrea forms a monophyletic group with the genera Arhyssus and Peliochrous based on the phragma at the junction of the first and second abdominal terga moderately developed; the well-developed apodeme of the seventh sternum in males; and the two dorsolateral lobes on the theca Chopra (1967). Niesthrea seems closely related to Arhyssus in sharing straight lateral pronotal margins, slender mutic hind femora, a distinct metathoracic scent gland, a relatively long labium, a grooved frons, and the lack of a distinct collar. Niesthrea is distinguished from Arhyssus by the proportionately narrower head width to length ratio (vs much wider than long), the longer labium that extends from the posterior margin of the hind coxae to abdominal segment IV (vs not extending beyond the hind coxae), and the large conspicuous median lobe of the male genital capsule (vs median lobe absent or greatly reduced). Peliochrous is distinguished from Arhyssus and Niesthrea in lacking a distinct groove on the frons and having the ocelli nearly touching the compound eyes ( Chopra 1967).

Figures

Fig. 2. Niesthrea male genitalia: (A) Ventral view. (B) Lateral view. Abbreviations: p, paramere; llb, lateral lobe; lpml, lateral projections of median lobe; mlp, median lobe of pygophore; bml, base of median lobe of pygophore.