Schiodtella formosana ( Takano & Yanagihara, 1939 )

Imura, Jimpei & Ishikawa, Tadashi, 2009, A review of Schiodtella formosana, with some remarks on the genus Schiodtella and description of a Japanese new species (Hemiptera: Heteroptera: Cydnidae), Zootaxa 2315, pp. 19-30 : 25-28

publication ID	https://doi.org/ 10.5281/zenodo.192017
DOI	https://doi.org/10.5281/zenodo.6226907
persistent identifier	https://treatment.plazi.org/id/03CE87E8-AB20-676C-FF6E-80B412C7FD96
treatment provided by	Plazi
scientific name	Schiodtella formosana ( Takano & Yanagihara, 1939 )
status

Treatment

Schiodtella formosana ( Takano & Yanagihara, 1939)

( Figs. 17–30 View FIGURE 17 – 21 View FIGURE 22 – 30 , 37–39 View FIGURE 31 – 39 )

Neostibaropus formosanus Takano and Yanagihara, 1939: 135 , pl. 4, fig. 19. Type locality: Taiwan.

Diagnosis. Head strongly wrinkled in dorsum ( Figs. 18, 19 View FIGURE 17 – 21 ); eyes very small ( Figs. 18, 19 View FIGURE 17 – 21 ); ocular index 13.5–16. Scutellum short and rounded, almost as long as wide ( Fig.17 View FIGURE 17 – 21 ). Peritreme lacking apical process ( Fig. 20 View FIGURE 17 – 21 ). Tarsi absent from all legs ( Figs. 22–25 View FIGURE 22 – 30 , 37–39 View FIGURE 31 – 39 ). Median arm of basal plate of penis shorter than lateral arms ( Fig. 26 View FIGURE 22 – 30 ); conjunctival appendage strongly protruding from phallotreme and recurved downwards in rest ( Fig. 27 View FIGURE 22 – 30 ).

Description. Male: ― total length 4.25–4.65; total width 2.8–3.0; body 2.35–2.5 high; head 0.95–1.0 long, 0.92–0.95 wide; length of antennal segments I 0.2, II 0.3–0.32, III 0.2–0.22, IV 0.35–0.38; length of rostral segments I 0.4, II 0.45, III 0.3–0.32, IV 0.32; pronotum 1.44–1.52 long, 2.36–2.7 wide; scutellum 1.85–1.95 long, 1.8–1.95 wide; hemelytron 2.8–2.86 long.

Body yellowish brown to brown; dorsum of head and anterior part of pronotum blackish. Eyes reddish; ocelli orange to reddish. Antennae and rostrum yellowish brown. Hemelytral membranes hyaline. Legs yellowish brown; apical half of protibia and corbicle of metatibia blackish.

Total length about 1.5 times as long as total width, 1.8 times as long as body height. Head ( Figs. 18, 19 View FIGURE 17 – 21 ) slightly longer than wide, strongly wrinkled in dorsum; clypeus ( Fig. 18 View FIGURE 17 – 21 ) slightly shorter than paraclypei; paraclypeus ( Figs. 18, 19 View FIGURE 17 – 21 ) fringed with 7–10 peg-bearing tubercles, and with several setae anteroventrally; primary setae III–V ( Figs. 18, 19 View FIGURE 17 – 21 ) peg-like, thinner than secondary ones. Eyes ( Figs. 18, 19 View FIGURE 17 – 21 ) very small, weakly prominent; ocular index 13.5–16; ocellar index 6.5; interocellar index 3.3–3.5. Antenna covered with thin, sparse setae in segments I and II, and dense setae in III and IV; approximate proportion of segments I to IV 1.0: 1.5: 1.0: 1.8. Rostrum surpassing procoxae; approximate proportion of segments I to IV 1.3: 1.5: 1.0: 1.0. Pronotum ( Fig. 17 View FIGURE 17 – 21 ) distinctly wrinkled in anteromedial part and posterior half, mixed with punctures in posteromedial part, and with 14–19 setae on lateral margin and 1 seta behind callus ( Fig. 16 View FIGURE 10 – 16 ), on each side. Scutellum ( Fig. 17 View FIGURE 17 – 21 ) short, rounded apically, almost as long as wide, entirely wrinkled. Thoracic pleura smooth except evaporatoria; peritreme without apical process ( Fig. 20 View FIGURE 17 – 21 ). Hemelytron ( Fig. 17 View FIGURE 17 – 21 ) short, not reaching tip of abdomen; corium ( Fig. 17 View FIGURE 17 – 21 ) indistinctly covered with fine punctures and wrinkles, and with 6 or 7 setae on costal margin; clavus ( Fig. 17 View FIGURE 17 – 21 ) with 1 seta basally. Protibia ( Fig. 22 View FIGURE 22 – 30 ) covered with setae between proximal 2/5 and distal 1/5 of anterior side, and with 5 spines on tibial edge. Setae of mesotibia gradually becoming longer and stouter toward tibial apex in anterior and dorsal sides ( Fig. 23 View FIGURE 22 – 30 ). Hind leg ( Figs. 24, 25 View FIGURE 22 – 30 ) considerably stout; setae on tibia gradually becoming longer and stouter toward corbicle; corbicle bearing stout spines, with 1 rough, longitudinal line of spines. Tarsi absent from all legs. Abdominal sternites III to VII moderately covered with setae of various length and thickness, especially in lateral part. Genital capsule with medial process on apicoventral margin. Penis ( Figs. 26, 27 View FIGURE 22 – 30 ) with strongly sclerotized and pigmented theca; median arm of basal plate shorter than lateral arms ( Fig. 26 View FIGURE 22 – 30 ); conjunctival appendage strongly protruding from phallotreme and recurved downwards in rest ( Fig. 27 View FIGURE 22 – 30 ). Paramere ( Figs. 28–30 View FIGURE 22 – 30 ) somewhat elongate, moderately covered with setae; hypophysis sharpened ( Figs. 28–30 View FIGURE 22 – 30 ).

Female: — not available in this study.

Material examined. 23, Chiwei, Chishan, Kaohsiung Hsien, Taiwan, 4.II.1934, M. Yanagihara leg. ( ELKU).

Distribution. Taiwan is the definite locality of this species at present, because previous distributional records are most probably erroneous for mainland China and Japan.

Remarks. The most remarkable characteristic of Sc. formosana is the absence of tarsi from all legs, which easily distinguishes this species from the other members of Schiodtella . Regarding the peculiarity of this characteristic for its taxonomic value, Takano and Yanagihara (1939) appear to have established the new genus Neostibaropus to accommodate the simultaneously described species N. formosanus (= Sc. formosana ). Actually, the lack of tarsi is considered a notable feature worthy of establishing a new genus for not only this species but also any other species of Scaptocorini. However, Sc. formosana has several important characteristics which are common to other congeners of Schiodtella , such as the four-segmented antennae, the peg-bearing tubercles fringed along the margin of the paraclypeus, and the abdomen with a 1+1 trichobothrial formula on the sternites III to VII, as documented by Lis (1999) and Lis and Hohol-Kilinkiewicz (2001). In addition to these characteristics, the penis structure may be sufficiently distinct for this species to be included in Schiodtella . Every species of this genus possesses the conjunctival appendage on the venter of the endosoma of the penis. The appendage serially varies from externally invisible as in Sc. secunda ( Lis 1991b) to large and long as in Sc. japonica sp. nov. through medium-sized as in Sc. laevicollis ( Montandon 1897) and Sc. subglabra ( Breddin 1900) . The appendage of Sc. formosana is large and long, being most similar to Sc. japonica sp. nov. among the congeners of Schiodtella . The range of variation in the appendage, then, also allows Sc. formosana to remain in Schiodtella . Perhaps Sc. formosana is more closely related to Sc. japonica sp. nov. than the other species of Schiodtella .

The absence of tarsi from all legs is also observed in the Afrotropical Afroropus bocagei (de Carvalho 1969) and the Neotropical Atarsocoris giselleae (= A. macroptera). However, Sc. formosana is separable from these two species by the paraclypeus fringed with peg-bearing tubercles.