Metoisops Popov and Herczek, 1992

Kim, Junggon, Taszakowski, Artur, Herczek, Aleksander, Zmarzły, Marzena & Jung, Sunghoon, 2023, New species of mirid insects and their importance for the higher classification of plant bugs, Acta Palaeontologica Polonica 68 (1), pp. 75-83 : 77

Genus Metoisops Popov and Herczek, 1992

Type species: Metoisops kerzhneri Popov and Herczek, 1992 ; Poland, Baltic amber, mid-Eocene (ca. 44.1±1.1 Ma according to Wappler 2005).

Emended diagnosis.—Differs from other extinct genera in the subfamily Isometopinae by body elongated oval, small to moderate, approximately 2.4–3.3 mm; dorsum deeply punctate, covered with densely long and golden pubescence; compound eye slightly prominent; ocelli large or medium sized; length of second antennal segment almost same as third and fourth segments combined; in some species fourth antennal segment subdivided; vertex wide; labium exceeding hind coxae, reaching first or third abdominal segment; posterior margin of pronotum straight or slightly concave in middle; pronotal collar narrow; calli weakly swollen; propleuron distinctly punctate ( Figs. 2A 2 , 3A 2 , A 3 ); mesoscutum narrowly or normally developed; hemelytral membrane with two cells; tarsi two segmented.

Description.—See Herczek and Popov (2014) for detailed redescription.

Remarks.—We propose herein the tribal replacement of Metoisops to the Gigantometopini based on the major morphological characters. See the discussion section below for details.

Herczek and Popov (2014) provided illustrations of each fossil specimen classified to Metoisops to date. In some species (e.g., Metoisops intergerivus Herczek and Popov, 2014 , and Metoisops punctatus Popov and Herczek, 1993 ), the fourth antennal segment is subdivided, reminiscent of the antennae with five or six segments, what is unique in Miridae . Nonetheless, the species possessing the subdivided fourth antennal segment are currently affiliated in the same genus. At this point, these species remain in Metoisops pending fourth segment evaluation and confirmation of the monophyly based on the phylogenetic approach. The state of fourth antennal segment subdivided may be used as a diagnostic character for the subgeneric subdivision in accordance to the phylogenetic result.

Figures

Fig. 2. Mirid insect Metoisops michalskii Kim, Taszakowski, and Herczek sp. nov., holotype male, DZUS HE44-451-1-001, from the Baltic Amber Gdańsk Bay, Poland), mid-Eocene. Dorsal habitus (A1), lateral habitus (A2), head and thorax in lateral view and antennal structure (A3), abdomen and legs in lateral view (A4), hindtarsus (A5), genital segment with parameres (A6). Abbreviations: i, first antennal segment; ii, second antennal segment; iii, third antennal segment; iv, fourth antennal segment; iv-1, first subsegment of fourth antennal segment; iv-2, second subsegment of fourth antennal segment.

Fig. 3. Mirid insect Metoisops popovi Kim, Taszakowski, and Jung, sp. nov., holotype female, CNU CNUHHMF005, from the Baltic Amber (unknown locality on Baltic Sea Coast), mid-Eocene. Dorsal habitus.Arrow points to deep incision between calli (A1), lateral habitus (A2), head in dorsal view (A3), head in lateral view (A4), scutellum (A5), hindfemur with trichobothria (A6).