Isometopus (Isometopus) linnavuorii, Hosseini, 2017

Hosseini, Reza, 2017, A new species of Isometopus from Iran (Hemiptera: Heteroptera: Miridae: Isometopinae), Acta Entomologica Musei Nationalis Pragae (suppl.) 57 (1), pp. 23-34 : 25-31

Isometopus (Isometopus) linnavuorii sp. nov.

( Figs 1–5 ) Type material. HOLOTYPE: ♁, IRAN: GUILAN: Rasht (37°11′45″N, 49°38′25″E, 30 m), 27.–30.vii.2014, R. Hosseini lgt. PARATYPES: 4 ♁♁, the same data as holotype.The holotype and 3 paratypes deposited in the Natural History Museum of the University of Guilan , Rasht, Iran ; one paratype in the University of New South Wales, Sydney, Australia .

Diagnosis. The new species is recognized by the following combination of characters: body length 2.4–2.6 mm, eyes red or silver; ocelli contiguous to the eyes; head brown with black punctures; ocular index 0.9, antennal segments I 0.14–0.15× and II 0.80–0.85× longer than width of head, antennal segment II 0.5× longer than posterior width of pronotum. Pronotum 2.75–3.00× wider than long. Height of gena very short, 0.16× as high as eye ( Figs 3d,e ); head in frontal view 1.6× wider than high, pronotum dark brown, mesoscutum black, punctate, laterally brown, distinctly carinate; scutellum black with disk slightly raised, apex white; hemelytra whitish translucent, abdomen visible through hemelytra.

Description. Male. Colouration. Head brown with dense black punctures, eyes red or silver; ocelli hyaline, surrounded by red annuli; posterior margin of vertex light brown; frontal part of head between antennifers black or dark brown, antennifer distinctly whitish; gena dark brown or black, maxillary plate brown; clypeus dark brown; labium generally brown with sparse whitish setae; antennal segment I dark brown or black, antennal segment II pale brown, distal end dark brown, segments III and IV dark brown. Thorax: pronotum dark brown, with dense black punctures, lateral margins narrowly pale brown and posterolateral angles with pale brown marking; posterior margin of pronotum in the middle with a white marking; mesoscutum black, laterally brown. Scutellum black, apex whitish. Thoracic pleuron: propleuron light brown with dark punctures, mesepisternum and metepisternum brown, metathoracic scent gland evaporative area brown, peritreme light brown. Hemelytra stramineous, translucent, abdomen visible through them, R+M pale brown, cuneus translucent, internally with a pale brown marking, membrane bright hyaline. Legs generally pale brown; femora generally dark brown. Ventral side of body uniformly brown.

Structure, vestiture and texture. Body elongated, oval. Head densely punctate, eyes glabrous, immediately above the anterior margin of pronotum; ocelli distinctly raised, touching inner margin of eyes; region immediately above the antennifer and lower part of frons ridged; gena short, antennal segment I with a few setae, II–IV covered densely with whitish setae; head covered with whitish setae; labium surpassing metacoxae, reaching abdominal segments III to IV. Thorax: pronotum punctate, covered by long, whitish, hair-like setae, collar distinct, calli obsolete, posterior margin broadly bisinuate; propleuron punctate; evaporative area large, triangular shaped, almost same size of metepisternum, peritreme tongue shaped, reaching posterior margin of metepisternum ( Fig. 4b ). Mesoscutum exposed, punctate. Scutellum punctate, densely covered with long whitish setae, anterior margin of scutellum tumidly rasied, posteriorly acuminate. Hemelytra: clavus, anterior part of corium and embolium along to the clavus punctate, cuneus impunctate, cell membrane indistinct, hemelytra covered with golden setae, ventral side of body with whitish setae.

Male genitalia: pygophore covered with long hair-like setae, left paramere hook-shaped, sensory lobe tumid, apophysis tapered ( Figs 2 c–d), right paramere simple ( Figs 2 f–g), weakly arcuate, endosoma as in Figs 2 a–b.

Measurements (in mm). Body length 2.2–2.5, width 1.29–1.32; lengths of antennal segments: I – 0.1, II – 0.54–0.57, III – 0.34–0.39, IV – 0.13–0.17; ocellar width 0.06–0.09; interocellar width (in dorsal view) 0.06–0.09; width across eyes (in dorsal view) 0.65–0.69; interocular width 0.2; width of eye 0.22; ocular index 0.9; width of head across eyes (in frontal view) 0.64, height of head in frontal view 0.4, width between antennal annuli 0.25; height of eyes from frontal view 0.31; height of gena 0.03 mm; width of pronotum on posterior margin 1.1; length of pronotum in the middle 0.35–0.40; width of anterior part of pronotum 0.45 mm; antennal segment I 0.14–0.15× as long as diatone; antennal segment II 0.80–0.85× as long as diatone; antennal segment II 0.5× as long as basal width of pronotum; pronotum basally 2.75–3.00 times as broad as long as in middle; length of cuneus 0.4; length of labium 1.05; length of scutellum 0.67; width of scutellum at anterior margin 0.74.

Female. Unknown

Differential diagnosis. The new species belongs to the nominotypical subgenus Isometopus . It is close to I. vanharteni , and in spite of similarity to this and other Isometopus species known from the Middle East and Europe, the new taxon can be readily separated from all other species by using the revised key to the species of Isometopus based on AKINGBOHUNGBE (2012).

Etymology. The species is named in honour of Dr. Rauno E. Linnavuori, a good friend and colleague who introduced mirid bugs to me for the first time.

Collection circumstances. Collected by light trap near Populus sp. trees.

Distribution. Iran (Guilan province).

Key to the species of Isometopus known in Europe and the Middle East (based on males, modified from AKINGBOHUNGBE 2012).

1 Apical frontal margin finely carinate or marginate, more or less confluent with clypeus and mandibular plate, which are broadly visible in front. Hemelytra mostly glassy hyaline or at least with broad glassy hyaline bands. Subgenus Jehania Distant, 1910 . ........ 2

– Apical frontal margin strongly carinate, distinctly raised over base of clypeus and mandibular plate which are either strongly deflexed or depressed; if not, hemelytra distinctly opaque and frons ivory-white with contrasting dark punctures. Subgenus Isometopus Fieber, 1860 . ................................................................................................................... 4

2 Ocellar width equal to interocellar width, frons rugose-punctuate. .................................. ......................................................................... I. (J.) yemenensis Akingbohungbe, 2003

– Interocellar width at least 1.6× as broad as each ocellus; frons practically impunctate. ........................................................................................................................................ 3

3 Ocelli whitish translucent, interocellar width about 3.3× ocellar width; mesoscutum punctate; rostrum largely yellow-brown, reaching seventh abdominal sternite. ............... ......................................................................... I. (J.) carinifrons Akingbohungbe, 2006

– Ocelli together with surrounding annuli dark-red, interocellar width about 1.6× ocellar width; mesoscutum impunctate; rostrum largely dark reddish-brown to black, reaching fourth abdominal sternite. ................................... I. (J.) gharaati Akingbohungbe, 2012

4 Interocellar width equal to ocellar width. ....................................................................... 5

– Interocellar width at least 1.3× as broad as ocellus. ....................................................... 7

5 Head in frontal view about 1.3× as broad as high; cuneus pale yellow with apical mesal dark brown band. ........................................... I. (I.) longirostris Akingbohungbe, 1996

– Head in frontal view>1.3× as broad as high, cuneus not as above. .............................. 6

6 Head in front view about 1.5× as broad as high; antennal segment III dark-red with pale basal and apical extremities; cuneus unicolourous reddish-brown. .................................. .......................................................................... I. (I.) vanharteni Akingbohungbe, 2006

– Head in frontal view about 1.6× as broad as high, cuneus translucent, internally with a pale brown marking. .............................................................. I. (I.) linnavourii sp. nov.

7 Interocellar width more than 2× as broad as ocellus. ..................................................... 8

– Interocellar width less than 2× as broad as ocellus. ..................................................... 10

8 Head in front about 1.5× as broad as high; frons at level of ventral margin of eyes with ivory-white transverse stripes separated by distinct punctate grooves. ............................ ......................................................................................... I. (I.) taeniaticeps Puton, 1898

– Head in front less than 1.5× as broad as high; frons devoid of distinct ivory-white transverse stripes as indicated above. .................................................................................... 9

9 Head from dorsal view rather strongly appressed, over 5× as broad as long; pronotum more than 3× as broad as long. ....................... I. (I.) intrusus (Herrich-Schaeffer, 1835)

– Head in dorsal view less strongly appressed, about 4× as broad as long or less; pronotum less than 3× as broad as long. .................................. I. (I.) diversiceps Linnavuori, 1962

10 Head in front 1.2× as broad as high; dorsum largely pale testaceous to ivory-white with broad blue-black blotches and bands. .................. I. (I.) mirificus Mulsant & Rey, 1879

– Head in front at least 1.3× as broad as high; dorsum either piceous to blackish or deep yellow to golden suffused with reddish. ....................................................................... 11

11 Dorsum deep yellow to golden suffused with reddish; head in front about 1.32× as broad as high. ............................................................ I. (I.) peregrinus Akingbohungbe, 1996

– Dorsum piceous to blackish; head in front about 1.48× as broad as high. ................... 12

12 Membrane of hemelytra densely covered with microsetae, biareolate; gena relatively low, less than 0.1× as high as eye. ..................... I. (I.) nigritulus Akingbohungbe, 1996

– Membrane of hemelytra glabrous, uniareolate; gena relatively higher, 0.2× as high as eye. ........................................................... I. (I.) praetermissus Akingbohungbe, 2012 *

Figures

Fig. 1. Habitus photographs of Isometopus linnavuorii sp. nov:A – dorsal view, B – ventral view; C – frontal view.

Fig. 2. Male genitalia of Isometopus linnavuorii sp. nov.: A, B – endosoma (A – lateral view, B – ventral view); C–E – left paramere, different views; F, G – right paramere, two different views.

Fig. 3. Scanning electron micrographs of Isometopus linnavuorii sp. nov.: A – body in dorsal view; B – body in ventral view; C –head in dorsal view; D, E – head in frontal view; F – head in fronto-ventral view. Scales = 100 μm unless otherwise marked.

Fig. 4. Scanning electron micrographs of Isometopus linnavuorii sp. nov.:A – prothorax, mesothorax and metathorax in lateral view; B – head, pronotum and scutellum in dorsal view; C – pygophore, dorsolateral view; D – antenna; E, F – tarsal claws. Abbreviations: EvA – evaporative area; Mts – metathoracic spiracle; Pe – peritreme. Scales = 100 μm unless otherwise marked.

Fig. 5. Head in frontal view. A – Isometopus diversiceps Linnavuori, 1962; B – I. gharaati Akingbohungbe, 2012; C – I. intrusus (Herrich-Schaeffer, 1835); D – I. mirificus Mulsant & Rey, 1879; E, F – I. kaznakovi Kiritshenko, 1939 (female and male); G, H – I. praetermissus Akingbohungbe, 2012 (G – female, H – male); I – I. quadrifasciatus Wagner, 1973; J – I. quadrivittatus Akingbohungbe, 2003; K – I. taeniaticeps Puton, 1898; L – I. sepehrii Linnavuori, Sarafrazi & Hosseini 1998; M – I.yemenensis Akingbohungbe, 2003; N – I.vanharteni Akingbohungbe 2006; O – I. linnavuorii sp. nov. Figs A, C, D, E, F, K, I after WAGNER (1973); L after LINNAVUORI et al. (1998); J and M after AKINGBOHUNGBE (2003); N after AKINGBOHUNGBE (2006) and Figs B, G, H after AKINGBOHUNGBE (2012).