Zemacrosaldula, Larivière, Marie-Claude & Larochelle, André, 2015

Larivière, Marie-Claude & Larochelle, André, 2015, Zemacrosaldula, a new genus of Saldidae (Hemiptera: Heteroptera) from New Zealand: taxonomy, geographic distribution, and biology, Zootaxa 3955 (2), pp. 245-266 : 247-248

Zemacrosaldula new genus

Type species. Salda australis White, 1876 , by present designation.

Description. Body length 4.22–6.28 (5.15) mm; elongate-ovate or broad-ovate. Dorsal colour somewhat speckled; largely blackish, with uniformly dark or, more rarely, narrowly pale lateral margins of pronotum, and a few to several, coalesced or individual pale markings on hemelytra, including a more or less defined line of three to four spots along R vein. Macropterous. Head not closely appressed to thorax (eyes distinctly separated from thorax), with three pairs of long trichobothrium-like setae (two dorsally on mandibular plates, two near preocellar furrows, two near preocellar spots). Frons with well-developed longitudinal furrow medially. Ocelli slightly elevated from surface of vertex, separated by the diameter of one ocellus or less, closer to each other than to eyes. Preocellar spots distinct, usually paler than surrounding area, subtriangular to crescent-shaped, narrowly to broadly touching eyes (by one ocellus width or more), slightly extending or not in front of ocelli. Preocellar furrows present, about as deep as longitudinal frontal furrow. Preocular spots indistinct, of same colour as surrounding area. Transverse swelling (postclypeus of Cobben) rather flat, slightly to moderately developed; lateral portions separated by a gap (mostly) or contiguous near facial midline. Mandibular plates rather flat, evanescent to moderately developed (not prominent or tumid). Maxillary plates slightly to moderately developed. Antennae largely dark; segment II completely dark or narrowly pale subapically only, at least 2.2x longer than I, clothed over entire length with very short setae (shorter than segment width), without long setae in apical half; segments III–IV not wider than apex of segment II, with short setae and a number of longer setae (subequal to segment width). Thorax. Pronotum: 0.51– 0.62x as long as scutellum medially; subtrapezoidal; lateral margins subrectilinear to slightly convex, more rarely sinuate-concave, uniformly dark or, more rarely, narrowly pale (pale area narrower than or about as wide as antennal segment II), not explanate and not separated from disc by a longitudinal furrow; collar present, continuous (not interrupted medially), delimited posteriorly by a row of punctures; calli not strongly raised although well differentiated from disc, contiguous, forming a transverse elevation with a median pit, delimited posteriorly by a row of punctures curving forward laterally and reaching lateral margins of pronotum. Underside: xyphus 2 elongate (as long as or longer than wide), subtriangular. Legs: hind tibiae with subapical comb; hind tarsal segment II 1.0– 1.4x as long as segment III. Hemelytra: without a distinct eyespot subbasally on exocorium; pubescence short, mostly semi-erect, whitish, more or less evenly distributed; clavus and corium largely pruinose or, more rarely, with pruinosity reduced on corium; costal margin slightly convex along entire length; costal fracture slightly curved forward, nearly reaching apex of R vein; embolar modification of female moderately ( Z. pangare ) to strongly developed; subapical pale spot of clavus present or absent; membrane with four well-formed cells, cell 2 about as long as cell 3, cell 4 distinctly longer than cell 3; hypocostal ridge simple; secondary hypocostal ridge absent. Abdomen. Venter largely black (never narrowly or broadly pale laterally) with or without posterior margin of segments narrowly pale. Paired eversible glands present; when externally visible, one gland located on each side near posterior margin of segment VII. Male parandria ( Figs 19–20 ) elongate, narrowly or broadly subtriangular; tip acuminate or obtusely rounded; inner membrane present along basal quarter to basal third of inner margins. Male paramere ( Figs 15–18 ) with or without distinct processus sensualis; dorsal margin bearing moderate to long setae. Male aedeagus containing three pairs of sclerites ( Fig. 23 , Z. australis ), two larger median branched sclerites and 4 smaller simple anterolateral sclerites. Male filum gonopori coiled approximately 1.25 or 1.5 times ( Figs 24 – 25). Female subgenital plate (segment VII, ventrally) with posterior margin produced caudally, truncate medially. Ovipositor with gonapophyse 1 distinctly serrate. Spermathecal pump flange present. Gynandrial gland sclerotised.

Remarks. The generic name Zemacrosaldula is derived from Ze- ( New Zealand) and Macrosaldula (Greek, makros = large; Latin, Saldula , feminine gender); the name of the Northern Hemisphere genus that Zemacrosaldula resembles. The authors think that this is the genus tentatively identified as Genus A by Polhemus (1985a), and said to represent the closest morphological and ecological analogue of Macrosaldula Southwood & Leston, 1959 .

The main morphological characters unifying the species of Zemacrosaldula are listed here, with generic level apomorphies from Polhemus (1985a) in italics: size relatively large (4.22–6.28 mm); dorsal colour somewhat speckled, largely blackish, with uniformly black or narrowly pale lateral margins of pronotum, and a few to several coalesced or individual pale markings on hemelytra, including a line of three to four spots along R vein; hemelytra lacking a distinct eyespot subbasally on exocorium; antennal segment II long, clothed over entire length with very short setae, without long setae in apical half; frons with well-developed longitudinal furrow medially; calli of pronotum with a distinct median pit and delimited posteriorly by a row of punctures reaching lateral margins; hemelytra and hindwings fully developed; membrane with four well-formed cells; embolar modification of female hemelytra well developed; hind tibiae with subapical comb; male aedeagus with anterolateral sclerites; processus sensualis of male paramere distinct or indistinct; filum gonopori of male coiled 1.25 or 1.5 times.

The male abdominal grasping plate was not studied in detail but preliminary observations in Z. australis indicate that it bears about 24 spines in the following configuration: an outer row of roughly 12 moderately long spines and an inner group of roughly 12 longer spines.

Zemacrosaldula species exhibit a high level of eunomic variability. Divergence from the ‘standard’ eunomy is common even within populations, and although it is possible to ‘perceive’ the identity of a species based on hemelytral pigmentation patterns, further confirmation is required from other morphological characters, including male genitalia. By the same token study material used for character analysis must consist of long series of specimens from any given population so as to sufficiently cover the range of morphological variations.

Cobben (1980a), in is study of Hawaiian Saldula , noted that environmental factors exert an influence on the proportion of colour morphs at the population level, e.g., high temperatures and/or lower humidity shift the eunomic series towards the light side of the sequence while cooler temperatures and/or higher humidity generally produce darker morphs. The authors have noted similar trends for Zemacrosaldula species, each occupying a distribution range encompassing broad and complex climatic conditions mainly caused by extensive topographical variation (e.g., from coastal lowlands to high mountains), wide-ranging temperatures (e.g., warm or cool temperate to severely cold) and precipitations (e.g., annual rainfalls of 600–4000 mm, and snow in the mountains). The authors have also observed that the pigmentation of newly emerged adults and females in general, tends towards the pale side of pigmentation spectrum.

Figures

FIGURES 15 – 24. Schematic views of male genitalia. (15 – 18) Paramere, ventral view. (15) Zemacrosaldula australis, (16) Z. kapekape (ph = processus hamatus), (17) Z. whakarunga (ps = processus sensualis), (18) Z. pangare. (19 – 20) Parandria, posterior view. (19) Z. australis, (20) Z. whakarunga. (21 – 22) Anterior half of aedeagus, lateral view. (21) Z. australis, (22) Z. whakarunga. (23) Sclerites of aedeagus, Z. australis, ventral view. (24 – 25) Filum gonopori, lateral view. (24) Z. australis, (25) Z. whakarunga.