Ommatidiotus Spinola, 1839

Park, Jaekook & Jung, Sunghoon, 2024, The genus Ommatidiotus Spinola (Hemiptera: Auchenorrhyncha: Caliscelidae) from the Korean Peninsula and neighboring countries, Zootaxa 5496 (2), pp. 172-190 : 175

Genus Ommatidiotus Spinola, 1839

Type species: Ommatidiotus dissimilis ( Fallén, 1806) (= Issus dissimilis Fallén, 1806 ).

Ommatidiotus Spinola, 1839: 365 ; Fieber, 1875: 362; Metcalf, 1958: 90; Emeljanov, 1999: 66.

Diagnostic characters. This genus distinguished by forewings with CuP ending at the apex of clavus ( Figs 1A– B ). Hind wings with M 2 and CuA 1; rm and mcu absent. First and second metatarsomeres are nearly equal in length ( Fig. 1C ). Aedeagus with hook- and tooth-shaped processes ( Figs 7C ; 11C ) ( Gnezdilov, 2011). See original descriptions for Spinola (1839) also.

Ecology. This genus is known to use acoustic signals for communication with both sexes ( O. dissimilis (Fallen) and O. inconspicuous Stål ; Tishechkin, 2003: 172, 177).

Distributions. This taxon is widely distributed in the Transpalearctic region. See the detailed distributions on the checklist below.

Remarks. Redivision of O. karafutonis stat. rev. and O. nigritus . These two species were established in the same protologue ( Matsumura, 1911), Anufriev & Emeljanov (1988) considered O. karafutonis to be a junior synonym of O. nigritus . The type series in SEHU ( Figs 4A–E ; 9A–E ) shows that these two species are distinct due to their coloration ( O. karafutonis : brown: O. nigritus : black) and body size ( O. karafutonis : 4.66-4.77 mm; O. nigritus : 4.58 mm; ‘ O. nigritus is similar in shape to O. karafutonis M., but slightly narrower.’) ( Matsumura, 1911). Thus, we considered O. karafutonis stat. rev. and O. nigritus as respective species, and revived the species status.

Presence of O. nigritus in the Korean Peninsula. The taxonomic issues of O. karafutonis stat. rev. and O. nigritus were discussed in the previous paragraph. O. karafutonis was previously recorded in the Korean Peninsula by Matsumura (1915). According to Anufriev & Emeljanov (1988), O. karafutonis is the junior synonym of O. nigritus , and Kwon et al. (1994) have changed the Korean record to O. nigritus . O. nigritus is being removed from the Korean fauna because we have reexamined the species status of O. karafutonis stat. rev. and revised the record.

Mismatch between female and male of O. nigritus . The blackish coloration of O. nigritus was described in the protologue, which corresponds with the female lectotype specimen ( Matsumura, 1911) ( Figs 9A–E ). According to Anufriev & Emeljanov (1988) which contrasts with the protologue: “In females, face and venter darkened, dorsal part of body light brown”. The male specimen in the SEHU collections complied with Anufriev & Emeljanov (1988) descriptions of external and genital characteristics ( Figs 10A–E ; 11A–F ). Further research is necessary to determine the cause of this issue whether it’s sexual dimorphism or specific species.

Figures

FIGURE 1. Diagnostic characters of the genus Ommatidiotus spp. A. right forewing, O. koreanus Matsumura, holotype; B. ditto, illustrated; C: metatasomere, Ommatidiotus sp. Scale bar: A–B: 1.0 mm; C: 0.5 mm.

FIGURE 4. Ommatidiotus karafutonis Matsumura, lectotype habitus.A. habitus, dorsal view; B. ditto, lateral view; C. head and thorax, dorsal view; D. ditto, lateral view; E. metope, ventral view. Scale bar: A–B: 1.0 mm; C–E: 0.5 mm.

FIGURE 7. Ommatidiotus koreanus Matsumura, holotype male genitalia. A. genitalia, lateral view; B. genital block, lateral view; C. aedeagus, left-lateral view; D. ditto, dorsocaudal view; E. genital style, ventral view; F. anal tube, dorsal view. Scale bar: A–C 0.5 mm; D–F: 0.1 mm.

FIGURE 9. Ommatidiotus nigritus Matsumura, lectotype habitus. A. habitus, dorsal view; B. ditto, lateral view; C. head and thorax, dorsal view; D. ditto, lateral view; E. metope, ventral view. Scale bar: A–B: 1.0 mm; C–E: 0.5 mm.

FIGURE 10. Ommatidiotus nigritus Matsumura, male habitus. A. habitus, dorsal view; B. ditto, lateral view; C. head and thorax, dorsal view; D. ditto, lateral view; E. metope, ventral view. Scale bar: A–B: 1.0 mm; C–E: 0.5 mm.

FIGURE 11. Ommatidiotus nigritus Matsumura, male genitalia. A. genitalia, lateral view; B. genital block, lateral view; C. aedeagus, left-lateral view; D. ditto, dorsocaudal view; E. genital style, ventral view; F. anal tube, dorsal view. Scale bar: A: 0.5 mm; B–C 0.3 mm; D–F: 0.1 mm.