Diorhabda elongata

Tracy, James L. & Robbins, Thomas O., 2009, Taxonomic revision and biogeography of the Tamarix-feeding Diorhabda elongata (Brullé, 1832) species group (Coleoptera: Chrysomelidae: Galerucinae: Galerucini) and analysis of their potential in biological control of Tamarisk, Zootaxa 2101 (1), pp. 1-152 : 39-40

Key to the Species of the Diorhabda elongata Group: Adult Males

1. Elongate (ventral) endophallic sclerite (EES) armed with spines on blade (SL) extending over an area less than or equal to 0.16 times (or less than about one fifth) the length of the sclerite, and blade (LB) extending less than or equal to 0.42 times the total length of the sclerite; EES never bearing a lateral appendage, lateral notch (pointed basally), or hooked apex ( Figs. 14 , 19 , 24 ). Palmate (dorsal) endophallic sclerite (PES) with distal margin usually broadly rounded and with one to six (commonly two to four) usually subdistal spines (SDS) (maximum of two distal spines, DS), and no lateral appendage (rarely with a lateral notch, LN) ( Figs. 14 , 29 ). Subsutural (SSV) and submarginal elytral vittae (SMV), if present, never extending from apical half of elytra into the basal half ( Fig. 1 ). Length 5.3–6.8 mm. Circummediterranean, Portugal, Bulgaria, Macedonia, S. Russia (Dagestan Republic), W. North America (introduced), commonly collected from coastal C. Turkey to Italy...................... elongata (Brullé)

- Elongate endophallic sclerite armed with spines on blade extending over an area greater than or equal to 0.31 times (or greater than about one third) the length of the sclerite, with blade extending greater than or equal to 0.43 times the total length of the sclerite; EES sometimes bearing a lateral appendage (LA), lateral notch (LN, pointed basally) or hooked apex (HA) ( Figs. 15–18 , 20–23 , 25–28 ). Palmate endophallic sclerite with distal margin truncate serrate and with two to six (commonly three to five) usually distal spines (maximum one spine subdistal) and a lateral appendage ( Figs. 15–16 , 30–31 ), or with distal margin narrowly or acutely rounded and one or two small subdistal spines and no lateral appendage (sometimes with lateral notch) ( Figs. 17–18 , 32–33 ). Subsutural and submarginal elytral vittae, if present, often extending from apical half of elytra into the basal half ( Figs. 5, 9 ). Length 4.2–7.3 mm. Portugal, Spain, France, N. Africa, Senegal, Yemen, S. Ukraine, S. Russia, Turkey, Syria, Transcaucasus, Iraq, Iran, C. Asia, Pakistan, N.W. and N.C. China, S.W. Mongolia, W. North America (introduced).............................. 2

2(1). Palmate endophallic sclerite bearing a strong lateral appendage and its distal margin truncate-serrate with two to six (commonly three to five) usually distal spines (maximum one spine subdistal) ( Figs. 15–16 , 30–31 ). Elongate endophallic sclerite with spines along blade often irregularly spaced with conspicuous gaps ( Figs. 15–16 , 20–21 ). Length 5.0– 7.3 mm. Portugal, Spain, France, N. Africa, Senegal, Yemen, S. Ukraine, Turkey, Syria, Transcaucasus, C. Asia (east to N.W. China and Pakistan), Iraq, Iran, W. North America (introduced) ............................................ 3

- Palmate endophallic sclerite never bearing a lateral appendage (rarely bearing a lateral notch) and its distal margin narrowly or acutely rounded, with one or two small subdistal spines that may project beyond the distal margin ( Figs. 17–18 , 32–33 ). Elongate endophallic sclerite with spines usually evenly and closely spaced along blade ( Figs. 17–18 , 22–23 ). Length 4.2–6.1 mm. S. Russia, Transcaucasus, Syria, Iran, C. Asia, Pakistan, N.W. and N.C. China, S.W. Mongolia, W. North America (introduced) ............................................................................................ 4

3(2). Lateral appendage (LA) of elongate endophallic sclerite always present and connected to lateral appendage of palmate endophallic sclerite by thin linear connecting (lateral) endophallic sclerite (CES) ( Figs. 16 , 21 , 31 ) (in some weakly sclerotized specimens, the lateral appendage of the elongate endophallic sclerite and the connecting endophallic sclerite may be faint and appearing to evanesce). Length 5.0– 6.9 mm. Portugal, Spain, France, N. Africa, Senegal, Yemen, Iraq, W. North America (introduced) ...................................................... sublineata (Lucas)

- Lateral appendage of elongate endophallic sclerite usually absent or very weak and never connected to lateral appendage of palmate endophallic sclerite by a linear connecting endophallic sclerite ( Figs. 15 , 20 , 30 ) (in some darkly sclerotized specimens, a faint line connecting the lateral appendages of the palmate and elongate endophallic sclerites should not be interpreted as a developed connecting endophallic sclerite). Length 5.1–7.3 mm. S. Ukraine, Turkey, Syria, Transcaucasus, C. Asia (east to N.W. China and Pakistan), Iraq, Iran, W. North America (introduced) ............................................................................................................................... carinata (Faldermann)

4(2). Apex of elongate endophallic sclerite not hooked in dorsal aspect, but often bearing a lateral notch ( Fig. 27 ; LN); blade of elongate endophallic sclerite extending from 0.48–0.66 times the total length of the sclerite ( Figs. 17 , 22 ; LB). Ratio of width to length of palmate sclerite ranging from 0.61–1.02; distal margin of palmate endophallic sclerite acutely rounded ( Figs. 17 , 32 ). Length 4.6–6.1 mm. S. Russia, Transcaucasus, Iran, C. Asia, N.W. and N.C. China, S.W. Mongolia, W. North America (introduced) ...................................................... carinulata (Desbrochers)

- Apex of elongate endophallic sclerite strongly hooked in dorsal aspect ( Fig. 28 ; HA); blade of elongate endophallic sclerite extending from 0.67–0.84 times the total length of the sclerite ( Figs. 18 , 23 ). Ratio of width to length of palmate sclerite ranging from 0.35–0.63; distal margin of palmate endophallic sclerite narrowly rounded ( Figs. 18 , 33 ). Length 4.2–5.6 mm. Syria, Iran, Pakistan............................................................... meridionalis Berti & Rapilly

Figures

FIGURES 14–18. Male genitalia: median lobe (ML) of aedeagus with everted endophallus (END; uninflated) (lateral and dorsal views).14—Diorhabda elongata, 15—D. carinata, 16—D. sublineata, 17—D. carinulata, 18—D. meridionalis. BF—basal foramen (or basal orifice), CES—connecting endophallic sclerite, DO—dorsal ostium (or apical orifice); EES—elongate endophallic sclerite, GP—gonopore, LA—lateral appendage, LB—length of blade, PES—palmate endophallic sclerite, SL—length of spined area of blade, VM—ventral membrane. Scale bar 1.0 mm.

FIGURES 19–23. Elongate (ventral) endophallic sclerite (lateral view) with connecting (lateral) endophallic sclerite (dorsal view, when present). 19—Diorhabda elongata, 20—D. carinata, 21—D. sublineata, 22—D. carinulata, 23—D. meridionalis. CES—connecting endophallic sclerite, EES—elongate endophallic sclerite, LA—lateral appendage, LB—length of blade, LN—lateral notch, SL—length of spined area of blade. Scale bar 1.0 mm.

FIGURES 24–28. Elongate (ventral) endophallic sclerite (dorsal views and a single dorso-lateral view [DLV]). 24—Diorhabda elongata, 25—D. carinata, 26—D. sublineata, 27—D. carinulata, 28—D. meridionalis. BL—blade, HA —hooked apex, CES—connecting endophallic sclerite (partial), EES—elongate endophallic sclerite, LA—lateral appendage, LB—length blade, LN—lateral notch. Scale bar 1.0 mm.

FIGURES 29–33. Palmate (dorsal) endophallic sclerite (dorsal view). 29—Diorhabda elongata, 30—D. carinata, 31—D. sublineata, 32—D. carinulata, 33—D. meridionalis. CES—connecting endophallic sclerite, DS—distal spines, EES—elongate endophallic sclerite, LA—lateral appendage, LN—lateral notch, PES—palmate endophallic sclerite, SDS—subdistal spines. Scale bar 1.0 mm.

FIGURES 1–9. Dorsal habitus of males (dead - top row, living - bottom row) of the Diorhabda elongata species group (tamarisk beetles): 1–2—D. elongata (Mediterranean tamarisk beetle), 3–4—D. carinata (larger tamarisk beetle), 5–6—D. sublineata (subtropical tamarisk beetle), 7–8—D. carinulata (northern tamarisk beetle), 9—D. meridionalis (southern tamarisk beetle). SSV—subsutural elytral vitta, SMV—submarginal elytral vitta. Scale bar 5.0 mm.