Suaediola Dorchin, 2019

Dorchin, Netta, Danon, Gilad & Dor, Roi, 2019, Gall midges (Diptera: Cecidomyiidae) associated with Suaeda (Chenopodiaceae) in Israel and the Mediterranean Basin, Israel Journal of Entomology (Oxford, England) 49 (2), pp. 99-134 : 126-129

Suaediola Dorchin , n. gen.

LSID: urn:lsid:zoobank.org:act:D88B16C7-0B0C-4DE3-9AA2-B46D2C8B83C5 .

Etymology: Suaediola combines Suaeda , the host of all known species in this genus, with the diminutive suffix ‘ola’, with reference to the generally small size of the midges.

Type species: Suaediola quotidiana Dorchin , n. sp.

Diagnosis: This genus belongs to the subtribe Baldratiina within the tribe Lasiopterini based on the characteristic morphology of adults and the association with Chenopodiaceae host-plants. Suaediiola resembles Careopalpis and Stefaniola in its small size, lack of spatula in the third-instar larva, and the overall chubby appearance of adults. Baldratia , by contrast, is usually larger and more slender in all developmental stages, and its third-instar larvae have a well-developed spatula. Suaediola resembles Careopalpis also in the invariable number of ten antennal flagellomeres (their number often irregular in Baldratia and Stefaniola ) but is easily distinguished from it by the dorsally rather than ventrally curved aculeus of the female ovipositor. It differs from Izeniola Fedotova and Stefaniola in the presence of a dorsal saddle-like projection at the base of the lateral plate of the female cercal segment, and the aculeus that is narrowed abruptly past its mid-length to form a dorsally curved sickle. By contrast, Izeniola and Stefaniola have a uniformly curved or straight aculeus and the ovipositor in Izeniola is strikingly longer. A molecular study currently underway (Dorchin & Dor, in prep.) suggests that the genera most closely related to Suaediola are Izeniola and Careopalpis , whereas Stefaniola is more distantly related to it.

Description: Adult. Head ( Fig. 38): Eye facets round; gap between eyes on vertex 0–2 facets wide. Antenna: 10 flagellomeres in both sexes, occasionally two adjacent flagellomeres partially fused; flagellomeres barrel-shaped to almost quadrate in both sexes, without necks, each with 1–2 whorls of appressed, interconnected circumfila, 1 whorl of strong setae on prominent sockets between two circumfila whorls, 1 whorl of thinner, shorter setae proximal to circumfila, evenly setulose elsewhere. Frontoclypeal membrane with long setae and scales. Palpus 1-segmented, strongly reduced, 1–2 times as long as wide, setulose, with few long setae. Labella strongly reduced to completely absent.

Thorax: Wing transparent, with sparse delicate hair-like setae on entire surface; C broken beyond junction with R 4+5; R 4+5 reaching C proximal to mid-length of wing; C and R 4+5 very thick and densely covered by scales to meeting point; M 4 absent, M 1+2 straight, CuA curved posteriorly past mid length. Legs ( Fig. 39): Tarsal claws toothed on all legs, moderately and evenly arched, tooth curved close to base; empodia longer than bend in claw; pulvilli 0.3–0.5 times as long as claw.

Female abdomen ( Fig. 40): Densely covered by scales forming black-and-white pattern along dorsum. Tergites 1–6 rectangular, with no anterior pair of trichoid setae, posterior row of strong setae, and evenly distributed scales; tergite 7 same vestiture but somewhat longer than preceding; tergite 8 shorter and smaller than 7, pigmentation considerably reduced, without any vestitutre. Sternites 2–7 rectangular, without anterior trichoid setae, with few setae forming posterior row along pigmented section and several setae medially; sternite 8 with small patch of pigmented area or undifferentiated from surrounding membrane, more setose than preceding. Ovipositor ( Figs 41, 42): Segment 8 with large lateral group of straight to slightly curved setae on prominent sockets; segment 9 with pigmented patches basally, pigmented rod-like sclerite along segment, and few long setae apicoventrally. Cercal segment in straight or almost straight position relative to segment 9, with distinct proximal plate sheathing base of segment, ventral shallow depression with field of closely packed short setae, sclerotized lateral plate with proximal saddle-like projection dorsally and about 20 straight to slightly curved setae on prominent sockets laterally; aculeus formed proximally of elongation of lateral plate, abruptly narrowed past mid-length, tapering into sickle-shaped spine distally; proximal section with several long, hooked setae; distal sickle-shaped section without setae. Apical lamella variably shaped, as long as or slightly longer than aculeus, setose and setulose.

Male abdomen: Tergites 1–7 rectangular, vestiture as in female; pigmented part of tergite 8 greatly reduced or tergite completely undifferentiated from surrounding tissue. Sternites 2–7 without proximal trichoid setae, with 1–2 posterior rows of very long setae and several long setae medially; sternite 8 considerably shorter and much less pigmented than preceding, with several setae. Terminalia ( Fig. 43): Compact and stout. Gonocoxite cylindrical, almost same width throughout length, with numerous long and strong setae ventrally, more numerous next to articulation with gonostylus; dorsal part of mediobasal lobe undeveloped, ventral section wide at base, tapered distally, divided apically into several short lobes, sheathing aedeagus almost to apex, densely setose. Gonostylus widest at mid length, tapering gradually toward small to medium tooth; evenly setulose dorsally and ventrally, with several setae more closely situated close to tooth.Aedeagus truncate or with small notch apically. Hypoproct entire, rounded apically or with very shallow depression, setulose. Cerci widely separated at least to mid-length, rounded apically, setose and setulose.

Larva (third instar). Light orange. Cylindrical. Integument covered by tapered verrucae. Spatula absent. Vestiture greatly reduced, hardly discernible. Otherwise not studied or unknown.

Pupa ( Figs 46, 47). Light orange. Antennal bases well developed into tapered horns, pointed ventrally. Vertex with short cephalic seta on prominent bulge. Prothoracic spiracle about 3 times as long as wide. Face with prominent, straight anterior horn and prominent, slightly curved and wide-based posterior horn; no facial papillae present. Dorsum of abdominal segments with tiny, tapered spicules.

Remarks: The genus currently includes four species, all from leaf or stem galls on Suaeda species in Israel, Egypt (Sinai), Jordan, Arabia, and possibly Northeast Africa. Three of these species, Suaediola defoliata (Dorchin, 2001) n. comb., Suaediola rufa (Dorchin, 2001) n. comb. and Suaediola siliqua (Dorchin, 2001) n. comb., were originally described under Stefaniola (Dorchin 2001) and are transferred here to the new genus based on morphology of the female ovipositor and on molecular evidence (Dorchin & Dor, unpubl. data). It is possible that additional species within the large and morphologically diverse Stefaniola will prove to belong in Suaediola , when subjected to a more careful morphological study and in particular when molecular data become available for them.