Paralimnini Distant, 1908

Zahniser, James N. & Dietrich, Chris H., 2013, A review of the tribes of Deltocephalinae (Hemiptera: Auchenorrhyncha: Cicadellidae), European Journal of Taxonomy 45, pp. 1-211 : 132-134

Paralimnini Distant, 1908

Figs 42 , 43

Type genus: Paralimnus Matsumura, 1902 .

Diagnosis

Paralimnini are small to medium sized leafhoppers. They can be identified by the combination of the following characters: clypellus tapering apically or parallel-sided, lorum narrower than clypellus at base; connective with anterior arms closely appressed, articulated with aedeagus; female first valvula sculpturing imbricate or rarely maculose or granulose. The tribe is very similar morphologically to the closely related Deltocephalini , from which it can be distinguished by the articulation between the connective and aedeagus (fused in Deltocephalini ), although a few species of Flexamia (Paralimnini) have the connective fused to the aedeagus.

Description

HEAD. Head subequal to or wider than pronotum. Discal portion of crown glabrous with radial or longitudinal striae, or shagreen. Anterior margin of head shagreen. Frontoclypeus not tumid or tumid; texture shagreen. Clypellus parallel-sided or tapering apically; apex following or slightly surpassing normal curve of gena. Lorum distinctly narrower than clypellus near base. Antennal bases near middle or posteroventral (lower) corners of eyes. Antennae short, less than 1.5 x width of head. Gena obtusely incised laterally; with fine erect seta beside laterofrontal suture. Antennal ledges absent. Ocelli present; close to eyes; on anterior margin of head.

THORAX. Pronotum lateral margin not carinate; lateral margin shorter than basal width of eye.

WINGS. Forewing macropterous to brachypterous; if macropterous then appendix absent, reduced, or present and restricted to anal margin; with 3 anteapical cells; veins not raised; without or rarely with reflexed costal veins; crossvein r-m1 often connected to R basad of its fork; A1-A2 crossvein absent; apical venation not highly reticulate.

LEGS. Profemur with AM1 seta only; intercalary row with one row of five or more fine setae; row AV usually with short, stout setae or rarely with relatively long macrosetae. Protibia dorsal surface rounded, convex. Metafemur apex macrosetae 2+2+1. Metatarsomere I not expanded apically; plantar setae simple, tapered or rarely with one or more platellae.

MALE GENITALIA. Valve articulated with pygofer; lateral margin short, articulating with pygofer at a point. Pygofer dorsoapical margin incised to near mid-length; basolateral membranous cleft present; macrosetae well differentiated into several rows. Subgenital plates free from each other; usually articulated with valve, or rarely fused; macrosetae uniseriate laterally, with two lateral rows of macrosetae, with some irregularly arranged macrosetae near lateral margin, or reduced or absent. Style broadly bilobed basally, median anterior lobe pronounced. Basal processes of the aedeagus/connective absent or reduced or present, connected or articulated to connective or near base of aedeagus. Aedeagus with single shaft and gonopore. Connective anterior arms closely appressed anteriorly, linear- or loop-shaped); nearly always articulated with aedeagus, rarely fused to aedeagus (e.g., some Flexamia ).

FEMALE GENITALIA. Pygofer with numerous macrosetae. Ovipositor not protruding or rarely protruding far beyond pygofer apex. First valvula convex or not strongly convex; dorsal sculpturing pattern imbricate (with overlapping scales) or rarely granulose or maculose; sculpturing reaching dorsal margin or submarginal; without or rarely with distinctly delimited ventroapical sculpturing. Second valvula broad, gradually tapered; without dorsal median tooth; teeth on apical 1/3 or more; teeth small, regularly or irregularly shaped or absent.

Geography and ecology

Distribution: cosmopolitan. Paralimnini feed on grasses or sedges and are often abundant in grassland ecosystems. A case study of the North American genus Flexamia ( Whitcomb & Hicks 1988; Dietrich et al. 1997) examined the roles of host plants, geography, phenology, and phylogeny in the species level diversification of the genus. These studies showed that related species groups feed on the same or similar species of grass hosts and that host shifts occurred in the past, sometimes to distantly related grass species. Geographic partitioning of the grass host ranges and phenological differences of the leafhopper species contributed to the speciation of the group.

Psammotettix striatus (Linnaeus, 1758) and P. alienus (Dahlbom, 1850) transmit wheat dwarf virus and mosaic virus of winter wheat.

Remarks

Paralimnini contains 139 genera and 931 species. It is closely related to Deltocephalini , with which it shares a similar head morphology and the linear connective. Tetartostylini , which has a similar connective articulated with the aedeagus but has the subgenital plates fused to the valve and with unique apical spines, is also closely related to Paralimnini . Many species in understudied areas of the world remain to be described. For example, in just three publications, Stiller (2009; 2010a, b) described 59 new species in three genera of Paralimnini from South Africa.

Selected references

Emeljanov (1962), Knight (1974), Whitcomb & Hicks (1988), Webb & Heller (1990), Dietrich et al. (1997), Kamitani (1999), Dmitriev (2004b), Stiller (2009, 2010a, b).

Included subtribes:

Figures

Fig. 42. Paralimnini (Aglenina). Aglena ornata (Herrich-Schäffer, 1838). A–I. Standard views (see Material & Methods). G. Connective and style shown with aedeagus.

Fig. 43. Paralimnini (Paralimnina). A–C. Paralimnus angusticeps Zachvatkin, 1953. D–I. Psammotettix striatus (Linnaeus, 1758). A–I. Standard views (see Material & Methods).