Eurhadina (Singhardina) Mahmood (Hemiptera: Cicadellidae: Typhlocybinae) from China: A Review of the Asian Species with Descriptions of 14 New Species

Simple Summary In this study, 50 species of the leafhopper subgenus Eurhadina (Singhardina) Mahmood from China are reviewed based on comparative morphological characteristics, including 14 new species, four additional species and two new synonymies. A key to all Chinese Singhardina species is also provided. Abstract In this study, 50 species of the leafhopper subgenus Eurhadina (Singhardina) Mahmood from China are reviewed based on comparative morphological characteristics, including 14 new species: Eurhadina (Singhardina) amacularis, E. (S.) extensa, E. (S.) flaviscutella, E. (S.) foliiformis, E. (S.) galacta, E. (S.) gracilifurca, E. (S.) lata, E. (S.) parilintanonica, E. (S.) quadrimacularis, E. (S.) recta, E. (S.) scalesa, E. (S.) scamba, E. (S.) scandens and E. (S.) uprotrusa sp. nov. Four additional species E. (S.) fasciata, E. (S.) jarrayi, E. (S.) prima and E. (S.) zadyma are recorded from China for the first time. Two new synonymies are proposed. Eurhadina (Singhardina) flavescens Huang et Zhang, 1999 syn. nov. is synonymized with Eurhadina wuyiana Yang et Li, 1991 and Eurhadina rubromia Cai et Kuoh, 1993 syn. nov. is synonymized with Eurhadina (Singhardina) biavis Yang et Li, 1991. A key to all Chinese Singhardina species is also provided.


Introduction
The leafhopper genus Eurhadina Haupt, 1929 belongs to the subfamily Typhlocybinae within the family Cicadellidae (Hemiptera: Cicadomorpha) and is distributed in the Palearctic and Oriental regions. Its type species is Cicada pulchella Fallen, 1806 from Sweden [1]. Eurhadina includes three subgenera: Eurhadina (Eurhadina) Haupt 1929, Eurhadina (Singhardina) Mahmood 1967, and Eurhadina (Zhihadina)  , which includes only one species from China. Eurhadina now has 40 species in China with China now having the richest species diversity of this genus.
The subgenus Singhardina was proposed by Dworakowska [2]. Subsequently, five species in China, Singapore, India, and Vietnam were transferred from the nominate subgenus to it.
Until now, Singhardina comprised 68 described species, which were divided into six groups by Dworakowska according to morphological characteristics [3], in which 34 species from China belong to four species groups: E.     Body form and color patterns very similar to E. (S.) rubra, but brochosome area with a broad oblique stripe along distal margin.
Male genitalia: Lobe of pygofer side rounded, lower lobe not involuted and without finger-like appendage distally. Subgenital plate with long macroseta near basal 1/4; four moderate and four short macrosetae longitudinally from apical 1/3 to subapex and three rigid microsetae on apex. Connective with lateral arms weakly separated. Paramere with caudal part equal to combined length of anterior and central parts, five fine microsetae and sensory pores on caudal part. Aedeagal shaft slightly expanded from base and compressed posteriorly with two pairs of leaf-shaped and unbranched apical appendages; dorsal appendages slightly wider than ventral one.
Etymology. The specific epithet is derived from the Latin word "foliiformis", referring to aedeagal shaft with apical appendages leaf-shaped.
Notes. This new species resembles E. (S.) rubra in external characteristics, but differs in brochosome area with a wider oblique stripe along distal margin and the aedeagal shaft having two pairs of wide and leaf-like apical appendages.   Body creamy. Face sordid white. Crown, pronotum, and scutellum without patch. Scutellum yellowish pale, basal triangles yellowish green. Forewing pale white, without patch on basal half of corium and clavus; distal margin of brochosome area, ScP + RA vein, and lateral margin of apical area with light brownish oblique stripes; RP vein with a big light brownish patch centrally; first apical cell and its adjoining second apical cell covered with a semicircular yellowish-brown patch.
Male genitalia: Upper lobe of pygofer side rounded with a sclerotized protrusion dorsally. Subgenital plate slender with long macroseta near basal 1/4; three moderate and four short macrosetae longitudinally from apical 1/2 to subapex; several rigid microsetae on subapex. Connective long with lateral arms weakly separated. Paramere slightly expanded apically with caudal part equal to combined length of anterior and central parts, three fine microsetae and five sensory pores on caudal part. Aedeagal shaft with a pair of dorsal appendages branched basally; longer appendages slightly expanded centrally, arched toward outside and more than twice as long as inner branches; inner branches draw nearer to each other apically.
Measurement Etymology. This specific epithet is derived from the Greek word "galactos", referring to milky white forewing.
Notes. This new species resembles E. (S.) scandens sp. nov. in external characteristics and male genitalia, but it differs by the aedeagal shaft having a pair of dorsal appendages branched at base.     Body form and color patterns very similar to E. (S.) scalesa sp. nov., but somewhat longer and face with lighter coloration.
Male genitalia: Lobe of pygofer side brownish black with upper lobe serrated and lower lobe strongly pigmented. Subgenital plate with long macroseta near basal 1/3, seven moderate macrosetae longitudinally near apical 1/3 to subapex; three rigid microsetae near subapex and four on apex. Connective long with lateral arms widely separated. Paramere with caudal part shorter than combined length of anterior and central parts, seven fine microsetae and five sensory pores on caudal part. Aedeagal shaft with two pairs of unbranched apical appendages; dorsal appendages slightly expanded centrally and reaching 2/3 ventral ones; ventral appendages slender and simple.
Etymology. The specific epithet is derived from the Latin word "rectus", referring to dorsal appendages of aedeagal shaft bended at right angle in posterior view.
Male genitalia: Lobe of pygofer side pigmented terminally, upper lobe rounded distally. Subgenital plate with long macroseta near basal 1/3; seven moderate and one short macrosetae longitudinally near apical 1/3 to subapex; three rigid microsetae on apex. Connective long with lateral arms weakly separated. Paramere with caudal part shorter than combined length of anterior and central parts, six fine microsetae and four sensory pores on caudal part. Aedeagal shaft extremely expanded from base and compressed laterally with two pairs of slender apical appendages; dorsal appendages unbranched; ventral appendages bifurcate with two branches nearly 90 • angled in posterior view and outer branches equal to 1/2 inner ones in length.
Notes. This new species resembles E. (S.) rubra in external characters and genitalia, but it differs by the ventral appendages of aedeagal shaft bifurcate with two branches nearly 90 • angled in posterior view.   Body yellowish brown. Face brownish. Crown, pronotum and scutellum without patch. Scutellum yellowish and basal triangles pale yellowish green. Forewing pale white with clavus and its adjacent part of corium light yellowish brown; central part of corium pinkish; distal margin of brochosome area and ScP + RA vein with slender oblique stripe.
Male genitalia: Both lobes of pygofer side pigmented terminally, dorsal margin of lower lobe with several rigid microsetae laterally. Subgenital plate with long macroseta near basal 1/4, six short macrosetae near apical 1/3; several rigid microsetae near subapex and two on apex. Connective long with lateral arms weakly separated. Paramere with caudal part shorter than combined length of anterior and central parts, six fine microsetae and sensory pores on caudal part. Aedeagal shaft slim and arched in lateral view with two pairs of apical appendages; ventral appendages long and wide with a short branch at basal 1/3 arched toward outside; dorsal ones slender and simple.
Etymology. The specific epithet is derived from the Greek word "scambos", referring to aedeagal shaft with apical appendages curved toward outside in dorsal view.
Notes. This new species resembles E. (S.) rubra in external characteristics and male pygofer side lobe, but it differs from the latter in having a slim aedeagal shaft and dorsal appendages of aedeagal shaft with a branch basally.  Body creamy. Face brownish. Crown, pronotum and scutellum without patch. Forewing pale white, without patch on basal half of corium and clavus; corium pinkish centrally; distal margin of brochosome area, ScP + RA vein and lateral margin of apical area with slender light brownish oblique stripes, RP vein with a big light brownish patch.
Male genitalia: Lobe of pygofer side strongly pigmented terminally and upper lobe rounded. Subgenital plate with long macroseta near basal 1/4, three moderate and four short macrosetae longitudinally from apical 1/3 to subapex; several rigid microsetae near apical 1/3 and two on apex. Connective long with lateral arms weakly separated. Paramere blunt terminally with caudal part shorter than combined length of anterior and central parts, five fine microsetae and four sensory pores on caudal part. Aedeagal shaft slightly expanded from base and compressed posteriorly with two pairs of slender and simple dorsal appendages merged basally; lower dorsal appendages equal to 1/3 upper ones in length and four appendages arched toward four different directions in posterior view.
Etymology. The specific epithet is derived from the Latin word "scando", referring to four apical appendages of aedeagal shaft seeming to climb in posterior view.
Notes. This new species resembles E. (S.) scamba sp. nov. in the male genitalia, but differs from the latter in pale white forewing and the aedeagal shaft with unbranched apical appendages pointing toward four different directions in posterior view. Pygofer rounded; when upper lobe narrowed, usually with prominent short protrusion dorsally (without protrusion in E. (S.) parilintanonica) and with several rigid microsetae terminally; when upper lobe not narrowed and large, protrusion obliterated; lower lobe usually not serrated (serrated in E. (S.) amacularis). Paramere blunt terminally with a row of tightly fine microsetae and sensory pores near outer margin on caudal part. In relation to sternite 9, subgenital plate short with a row of short or moderate macrosetae and fine microsetae on apical 1/3, several rigid microsetae near subapex. Connective long. Aedeagal shaft with two pairs of apical appendages, dorsal appendages not bifurcate, ventral ones often bifurcate.   Body creamy. Crown, pronotum, and face yellowish orange. Crown with three creamy patches, remainder orange. Pronotum with two pairs of symmetrically oval creamy patches centrally and several small and irregular creamy patches anteriorly, remainder orange; basal triangles orange; scutellum yellowish pale with brownish apex, an orange patch centrally and two blackish marks on sides of scutellum. Forewing transparent with reddish patches on basal part of corium and clavus; basal margin of brochosome area yellow.
Male genitalia: Upper lobe of pygofer side large, lower lobe serrated and slightly pigmented distally. Subgenital plate with long macroseta near basal 1/3, six short macrosetae extend from apical 1/3 to subapex and several rigid microsetae on subapex. Connective with lateral arms widely separated. Paramere broadened with three fine microsetae and few sensory pores on caudal part. Aedeagal shaft slim and curved, with two pairs of unbranched apical appendages; ventral appendages sinuate and shorter than dorsal ones, dorsal appendages widened centrally.
Etymology. The specific epithet is derived from the Latin words "a" and "macula" referring to forewing lacking a patch except basal part of corium and clavus.
Notes. This new species belongs to the E. (S.) vittata group based on male genitalia, but differs from other species of this group in forewing transparent without round black patch on basal part of clavus and dorsal appendages of aedeagal shaft unbranched. "parilis" and the name of the related species "intanonica", referring to this new sp closely resembling E. (S.) intanonica.
Notes. This new species resembles E. (S.) intanonica in external characteristic male genitalia, but differs from the latter in aedeagal shaft with ventral appendag shaped and appearing between the two branches of dorsal appendages in dorsal vi Body transparent, face sordid white. Crown creamy with four small orange patches anteriorly. Pronotum with orange fascia anteriorly and two blackish round patches posteriorly. Scutellum yellowish orange, basal triangles blackish. Forewing transparent without patch on basal half of corium; clavus with a blackish round patch centrally and brochosome area with a short traverse stripe on costal margin.
Male genitalia: Upper lobe of pygofer side tuberculated distally, narrowed but without prominent short protrusion dorsally. Subgenital plate with long macroseta near basal 1/5, four short macrosetae near apical 1/3; two rigid microsetae on apex. Paramere slender and straight with three fine microsetae and four sensory pores on caudal part. Aedeagal shaft slim and curved, with two pairs of apical appendages; ventral appendages long and not branched, located between two branches of dorsal appendages; dorsal appendages bifurcate with inner branched with semi-lunar depression on apical 1/2 and wider than outer ones. Etymology. The specific epithet is derived from the combination of the Latin word "parilis" and the name of the related species "intanonica", referring to this new species closely resembling E. (S.) intanonica.
Notes. This new species resembles E. (S.) intanonica in external characteristics and male genitalia, but differs from the latter in aedeagal shaft with ventral appendages U-shaped and appearing between the two branches of dorsal appendages in dorsal view. Description. Coloration bright. Forewing always with various yellowish, orange to reddish coloration; clavus with or without brownish patch; distal margin of brochosome area with oblique stripe; RP vein without big brownish-black patch.
Male genitalia: Lobes of pygofer side long; upper lobe with a sclerotized protrusion terminally, lower lobe not pigmented and disc with two rigid setae. Subgenital slender, with long macroseta near basal 1/3; five short macrosetae extend from apical 1/2 to subapex; three rigid microsetae on apex. Connective long and with lateral arms weakly separated. Paramere with four sensory pores and five fine microsetae on caudal part. Aedeagal shaft expanded basally and compressed laterally with three pairs of unbranched apical appendages; ventral appendages V-shaped; dorsal appendages expand centrally, S-shaped and pointed outside in dorsal view; lateral appendages shorter than others, slender and slightly arched toward each other.
Etymology. The specific epithet is derived from the Latin word "extensivus", referring to aedeagal shaft extremely expanded basally.
Notes. This new species resembles E. (S.) choui in color pattern of forewing, but it can differ from the latter by aedeagal shaft expanded basally and with a pair of lateral appendages.
Eurhadina (  Body and face brownish. Crown creamy with four orange patches centrally. Pronotum brownish with two pairs of round patches symmetrically anteriorly, central patches orange and lateral patches brownish; several small brownish patches centrally. Scutellum yellow with basal triangles orange and apex blackish. Forewing brownish pale, color patterns as shown in Figures 206 and 207.
Male genitalia: Upper lobe of pygofer side long without sclerotized protrusion dorsally; disc of lower lobe with several fine microsetae. Subgenital with long macroseta near basal 1/3; five moderate macrosetae near subapex and four rigid microsetae on apex. Paramere straight and hooked caudally with four fine microsetae on caudal part. Aedeagal shaft slim with a small dorsal protrusion terminally and a pair of bifurcate dorsal appendages; upper branches of dorsal appendages longer and arched toward outer side, but terminally pointed toward each other; lower branches of dorsal appendages bent basad and widened apically.
Etymology. The specific epithet is derived from the combined Latin word "flavus" and "scutella" referring to the distinctly yellow scutellum.
Notes. This new species resembles E. (S.) extensa sp. nov. in external characteristics, but differs by its yellow scutellum and having just one pair of bifurcate dorsal appendages on aedeagal shaft.  Body light yellowish brown. Face brownish black. Crown sordid white with orange fascia posteriorly. Pronotum creamy with two orange patches anteriorly and a brownish patch centrally; basal triangles yellowish; scutellum creamy with apex blackish and a yellowish patch centrally. Forewing brownish orange, without patch on basal half of corium; brochosome area orange with a brownish broad oblique stripe along distal margin; RP vein with a brown spot centrally; lateral margin of apical cell and its adjoining partial region covered with irregular brownish patches.
Male genitalia: Upper lobe of pygofer side serrated with a rigid microsetae distally; lower lobe slightly pigmented. Subgenital with long macroseta near basal 1/3; five moderate macrosetae near apical 1/3 and four rigid microsetae on apex. Connective long with lateral arms weakly separated. Paramere with four sensory pores and three fine microsetae on caudal part. Aedeagal shaft slightly expanded centrally with four pairs of apical appendages; upper dorsal appendages slender and Y-shaped, lower dorsal appendages wide basally and V-shaped in dorsal view; both pairs of ventral appendages shorter, slender and merged basally.
Etymology. The specific epithet is derived from the combination of the Latin words "gracilis" and "furca" that refers to dorsal appendages of aedeagal shaft like a slender long fork and distinctly higher than other appendages.
Notes. This new species resembles E. (S.) choui in the color pattern of forewing, but it can be distinguished from the latter by aedeagal shaft with two pairs of ventral appendages.  Body and face reddish orange. Crown with a creamy longitudinal fascia, remainder reddish orange. Pronotum with a creamy longitudinal fascia and two triangular patches posteriorly, remainder reddish orange. Basal triangles pale yellowish, scutellum creamy with apex blackish, two blackish marks on sides of scutellum and an orange patch centrally.
Forewing orange with a blackish patch on central part of claval; a longitudinal pink stripe on corium, parallel to the other oblique stripe along claval furrow; brochosome area yellowish orange with a broad oblique brownish stripe along distal margin; apical cell covered with irregular brownish-yellow patches.
Male genitalia: Lobe of pygofer side pigmented terminally, upper lobe serrated and lower lobe with a horn-like appendage distally and disc of lower lobe with several rigid microsetae. Subgenital with long macroseta near basal 1/3; two short macrosetae near subapex and three rigid microsetae on apex. Paramere distinctly expanded caudally with three sensory pores and five fine microsetae on caudal part. Aedeagal shaft slim and with two pairs of apical appendages; both dorsal and ventral appendages pointed towards outside in dorsal view; ventral appendage shorter than dorsal ones and slightly expanded subapically with short and sinuated upper branches near basal 1/3.
Etymology. The specific epithet is derived from the Latin word "latus", referring to its paramere expanding apically.
Notes. This new species resembles E. (S.) dazhulana in external characteristics and male genitalia, but it can be differentiated by the shorter and sinuated upper branches of ventral appendages of aedeagal shaft in dorsal view.
Male genitalia: Caudal margin of upper lobe of pygofer side with several rigid microsetae laterally, lower lobe not pigmented. Subgenital with long macroseta near basal 1/4; three short microsetae extend from apical 1/4 to subapex and with five rigid microsetae on apex. Connective long with lateral arms weakly separated. Paramere blunt terminally with four sensory pores and three fine microsetae on caudal part. Aedeagal shaft slim and curved in lateral view with two pairs of unbranched and slender apical appendages; dorsal appendages shorter than ventral ones, and U-shaped; ventral appendages V-shaped in dorsal view.
Pygofer with large dorsal lobe and small ventral one; both lobes or the ventral ones pigmented distally; upper lobe usually tuberculated and serrated with several rigid microsetae terminally. Subgenital plate with narrowed apex not distinctly extended and with a row of moderate or short macrosetae extending from apical 1/3 to subapex. Paramere with caudal part distinctly shorter than combined length of anterior and central parts, with row of sensory pores on inner margin and fine microsetae on outer margin. Connective short. Penis usually with single dorsal appendages and bifurcate ventral appendages which along with lower branches shorter (lower branch reduced in E. (S.) prima, but longer in E. (S.) acapitata).