Spanagonicus Berg

Menard, Katrina L., 2015, A review of the genus Spanagonicus Berg (Hemiptera: Miridae: Phylinae: Nasocorini) with the description of novel antennal characters, the description of a new species from Central America, and a key to currently known taxa, Zootaxa 3973 (1), pp. 139-158 : 140-141

Spanagonicus Berg

Figures 1–6

Spanagonicus Berg 1883: 78 (n. gen.); Carvalho 1958: 142 (Cat.); Maldonado 1969: 86 (descr., key to spp.); Alayo 1974: 22 (diag.); Schuh 1984: 429 (diag., disc.)

Leucopoecila Reuter 1907: 24 (n. gen., syn. by Carvalho, 1952:66); Carvalho 1958: 142 Type species: Spanagonicus provincialis Berg, 1883 , by original description.

Diagnosis. Spanagonicus can be recognized by its small size, primarily dark brown coloration, inflated first and second antennal segments, and tuft of setae on posterolateral margin of the secondary gonopore in males.

Redescription. Male ( Fig. 1 A, D, F, H): Relatively small in size, generally ovoid in shape, length 2.1–2.7. COLORATION: Body dark brown to black; hemelytron light brown and nearly transparent to dark brown, sometimes with white markings on the clavus and corium; membrane brown, sometimes with lateral margins adjacent to apex of cuneus light brown to white, veins of cell dark brown; head dark brown to black; first antennal segment basally light yellow, apically dark brown to completely dark brown, second antennal segment dark brown to reddish brown; remaining segments dark brown; thorax and abdomen dark brown; evaporatory gland primarily dark brown, sometimes with light brown posterior and ventral margins; coxae and femora reddish brown to dark brown, tibiae golden to dark brown in coloration, basal tarsal segments golden to dark brown, apical segments dark brown. SURFACE AND VESTITURE: Dorsum smooth, pronotum and scutellum impunctate. Vestiture is comprised of: simple adpressed dark brown setae covering the entire body surface; a tuft of relatively long dark setae on posterolateral surface of gonopore; two pairs of relatively long setae on interior surface of first antennal segment; and a ventral patch of spatulate attachment setae on the ventral surface of second antennal segment ( Fig. 4 A–C; see Discussion). STRUCTURE: Head transverse, weakly exserted and not concave on posterior margin; eyes relatively large, taking up at least half height of head in lateral view, posterior margin of eyes partially surpasses anterior margin of pronotum; vertex visible in lateral view, interocular space less than one-half total dorsal width of head; clypeus weakly visible in dorsal view; apex of rostrum extends past hind-coxae; first antennal segment inflated, inverted-cup shaped to inverted bottle-shaped, second antennal segment inflated, ranging from mildly inflated medially to football-shaped with ventral surface with spatulate setae patch, remaining antennal segments narrow, third segment longest, fourth approximately 2/3 length of third segment; pronotal collar absent, pronotum trapezoidal, dorsally smooth, calli not visible to weakly developed, weak demarcation of anterior and posterior portions; mesonotum exposed; scutellum transverse, smooth; hemelytral margins straight, weakly tapering towards apex of wing, cuneus right-triangular in shape, well developed deflection; membrane well developed, with one cell; hind femora relatively robust; pulvilli small, parempodia setiform in tarsal claw; gonopore tapering apically, no ventral keel present, taking up less than 1/4th total area of abdomen. GENITALIA: ( Fig. 2 ) Endosoma tubular, C-shaped, well developed horse-collar shaped secondary gonopore present subapically, membrane extending apically and tapering to a point ( Fig. 2 A, D, G, J); right paramere small, leaf-shaped with medial, apical point; left paramere typical phyline in shape, posterior arm tapering to point, angled slightly downward relative to anterior arm ( Fig. 2 B, E, H, K); phallotheca smooth, C-shaped, relatively narrow at apex ( Fig. 2 C, F, I, L).

Female: ( Figs. 1 B, C, E, G, I, J) Ovoid in shape, sometimes brachypterous, length 2.1–2.7. COLORATION: As in males. SURFACE AND VESTITURE: Second antennal segment lacking ventral spatulate setae patch, and posterolateral margin of abdomen lacking patch of long setae. Remaining surface and vestiture as in males. STRUCTURE: Interocular space relatively wider and eyes smaller in females compared to males; first antennal segment inverted bottle-shaped, second antennal segment thickened relative to other segments but not inflated as in males, third and fourth segments narrow and linear; remaining structure attributes as in males. FEMALE GENITALIA: ( Fig. 3 ) Dorsal labiate plate with small but well developed sclerotized rings ( Fig. 3 B), sclerotized rings surrounded by sclerites extending anteriorly and dorsally to arms of rami ( Fig. 3 A); posterior wall of bursa copulatrix with a pair of sclerites at sides of the posterior margin ( Fig. 3 C), weakly sclerotized and weakly protruding dorsally along posterior margin ( Fig. 3 D); vulva surrounded by a pair of small triangular sclerites ( Fig. 3 A).

Hosts. Variable (see Table 1.). Host records from S. albisignatus .

Distribution. North and South America, Caribbean, and introduced to Hawaii and Guam.

Discussion. Illustrations of the male genitalia in this genus in earlier literature appear to be based on broken or impartial endosomas; all species observed in this genus thus far not only have a visible secondary gonopore (e.g. missing in illustration of S. albisignatus in Hernandez & Henry 2010), but a membranous extension that tapers into a point (e.g. missing in illustration of S. albisignatus in Schuh 1984). When complete specimens of all species are viewed across the genus, there is little variation. The main source of variation in this genus appears to be the exterior coloration, the shape and size of the second antennal segment in males, and the level of brachyptery in the females.

Figures

FIGURE 1. Dorsal habitus photos Spanagonicus Berg species. A. male S. albofasciatus (Reuter) B. female S. albofasciatus, macropterous C. female S. albofasciatus, brachypterous D. male S. argentinus E. female S. argentinus F. male S. aricanus G. female S. aricanus H. male S. schusterus I. female S. schusterus. J. female S. tiquensis (Image from the Museo de La Plata online holotype database). Images not to scale; see Table 2 for measurements.

FIGURE 2. Male genitalia of Spanagonicus Berg species. Spanagonicus albofasciatus: A. endosoma, B. left paramere, C. phallotheca; S. argentinus: D. endosoma, E. left paramere, F. phallotheca; S. aricanus: G. endosoma, H. left paramere, I. phallotheca; S. schusterus n. sp.: J. endosoma, K. left paramere, L. phallotheca.

FIGURE 3. Female genitalia of Spanagonicus albofasciatus. A. anterior view of vestibulum, B. dorsal view of vestibulum, C. dorsal view of posterior wall, D. posterior view of posterior wall. sre—sclerotized rings extensions. vs—vestibular sclerites. sr—sclerotized rings. ls—lateral sclerites. pw—posterior wall.

FIGURE 4. Scanning electron microscopy images of Spanagonicus albofasciatus. A. Lateral head and thorax view of male S. albofasciatus, B. Lateral view of second antennal segment of male S. albofasciatus, C. spatulate setae on ventral surface of second antennal segment in male S. albofasciatus, D. lateral view of female S. albofasciatus. Magnifications at base of images.

FIGURE 5. Transmission electron microscopy images of a cross-section of the second antennal segment in Spanagonicus albofasciatus. A. Female S. albofasciatus, B. Male S. albofasciatus. Cuticle for dorsal surface of the second antennal segment and ventral surface associated with the spatulate setae in male S. albofasciatus are indicated. Scale bars are equivalent to 1 micron.

FIGURE 6. Transmission electron microscopy images of a cross-section of the second antennal segment in Spanagonicus albofasciatus. A. Male S. albofasciatus dorsal cuticular surface, highlighting the basicornis setae and associated structures. B. Male S. albofasciatus ventral cuticular surface, highlighting the layers of cuticle and spatulate setae internal morphology. cucuticle p—pores, tr—trichogen cells, to—tormogen cells. Scale bars are equivalent to 1 micron.