Myrmeleon hyalinus hyalinus Olivier, 1811

Hassan, Muhammad Asghar, Zheng, Yuchen & Liu, Xingyue, 2022, Taxonomic notes on the antlion tribe Myrmeleontini Latreille (Neuroptera, Myrmeleontidae, Myrmeleontinae) from Pakistan, with description of a new species, European Journal of Taxonomy 831, pp. 1-44 : 21-26

Myrmeleon hyalinus hyalinus Olivier, 1811

Figs 12–15 , 20

Myrmeleon hyalinus hyalinus Olivier, 1811: 126 . Type locality: Saudi Arabia.

Diagnosis

It can be distinguished by the distinctive head and thoracic markings: frons black, except for ventral corner yellow ( Fig. 14B ); vertex black, median and posterior portions with yellow markings in dorsal view; pronotum yellow, medially with a longitudinal brownish stripe, anterior transverse furrow dark brown, distally with a pair of well-separated transverse brownish stripes ( Fig. 14C ); wings narrowly elongated, acutely pointed at apex, initial branching point of CuA distad Rs origin ( Fig. 13 ). Moreover, male genitalia is distinctive among species of Myrmeleon in Pakistan: gonocoxites 11 highly sclerotized, lateral arms elongated; gonostylus 11 rounded in lateral view; gonocoxites 9 narrow and elongated, wider in lateral view with pointed apex.

Material examined

PAKISTAN – Islamabad Capital Territory • 1 ♂; Quaid-e-Azam University, Shahdarah ; 33°45′5.1474″ N, 73°9′40.1754″ E; 555 m a.sl.; 24 Aug. 2019; Hassan M.A. leg.; CAU .

Re-description

MEASUREMENT (♂ n=1). Forewing: length 26.2 mm, width 5.5 mm; hind wing: length 26.2 mm, width 4.6 mm; body length: 24.0 mm.

HEAD ( Fig. 14B–C ). Vertex moderately raised; in frontal view black, without yellow markings; in dorsal view black, medially with a pair of transverse and posteriorly with a pair of longitudinal yellow markings; epicranial area black, with longitudinal grooves, covered with short brownish pubescence. Frons black, but ventral corner yellow, covered with short yellowish pubescence. Occiput and postorbital sclerites yellow. Clypeus yellow, medially with two indistinct dark brown markings. Labrum yellow, covered with erected brownish setae at proximal margin. Genae pale yellow. Maxillary and labial palps pale yellow, terminal labial palpomere spindle-shaped, palpimacula brownish, small and circular, with short black setae. Antennae brownish, dorsal ring of scape and pedicel yellow, covered with short black setae, flagellum brownish with proximal and distal margin dark brown. Antennal sclerites yellow ( Fig. 14B ).

THORAX ( Fig. 14A ). Pronotum slightly wider than long, yellow, medially with a longitudinal brownish stripe, slightly interrupted at anterior transverse furrow; dark brown stripe along anterior transverse furrow, not reaching at lateral margins; distally with a pair of well-separated transverse brownish stripes; covered with sparse yellow setae. Mesonotum dark brown; prescutum laterally with a narrow yellow stripe; mesoscutum with yellow markings on median and posterolateral margins; mesoscutellum at distal ⅔ yellow; covered with sparse yellow setae, but prescutum with long dark brown setae. Metanotum dark brown; prescutum medially with faintly brownish longitudinal yellow marking; metascutum distally with a pair of large yellow markings; metascutellum laterally and distally brownish yellow; covered with sparse yellow setae. Pleuron dark brown, with yellow markings, covered with sparse yellow setae ( Fig. 14E ).

LEGS ( Fig. 14E ). Foreleg: coxa and trochanter yellow, with short yellow setae. Femur yellow, light brownish at distal ½, with short black setae, but posterolaterally with a few long black setae at proximal half; femoral sense hair shorter than proximal ½ of profemora. Tibia yellow, with mixed, short and long black setae at proximal half, antennal cleaning setae yellow; tibial spurs brownish, straight, as long as Ta1. Tarsomeres yellow, with short black setae; Ta1 equal to combined length of Ta2–Ta3; Ta2, Ta3 and Ta4 nearly equal in size; Ta5 equal to combined length of Ta1–Ta3. Pretarsal claws brownish, curved. Mid leg: coxa yellow, slightly brownish at proximal ½, with yellow setae. Trochanter yellow, with short black setae. Femur yellow, light brownish at distal ½, covered with short black setae, laterally with a few long black setae at proximal half; femoral sense hair shorter than proximal half of mid femora. Tibia yellow, covered with mixed, short and long black setae; tibial spurs similar to foreleg. Tarsomeres and pretarsal claws similar to foreleg. Hind leg: coxa and trochanter similar to mid leg. Femur yellow, light brownish at distal ⅓, covered with short black setae, proximal half with a few long black setae; femoral sense hair absent. Tibia, tarsomeres, and pretarsal claws are similar to mid leg.

WINGS ( Fig. 13 ). Forewing as long as hind wing, acute at apex; membrane hyaline; costal area slightly narrow at proximal region; venation brownish yellow, covered with sparse short black setae; poststigmal area with a few interconnected crossveins; nine presectoral crossveins; initial branching point of CuA proximal to Rs origin; Rs with 11 branches; CuP origin at the same level to basal crossveins, fused with 1A after a short free base; pterostigma indistinct; anterior Banksian line absent; posterior Banksian present. Hind wing: relatively narrow, acute at apex; membrane hyaline; venation similar to forewing; five presectoral crossveins; median fork at proximal to Rs origin; Rs with 12 branches; pterostigma indistinct; anterior Banksian line absent; posterior Banksian indistinct; pilula axillaris small, with rounded knob covered with dense brown setae.

ABDOMEN ( Fig. 12 ). Tergites dark brown, distally with a narrow yellow stripe on terga 1–8, lateral margins yellow, covered with short brownish yellow setae. Sternites dark brown, distally with a narrow yellowish stripe, covered with short brownish yellow setae.

MALE GENITALIA ( Fig. 15 ). Tergum 9 subtrapezoidal in lateral view. Sternum 9 ovate-shaped, covered with long black setae at distal ⅓. Ectoproct nearly rectangular in lateral view, posteroventral corner slightly prominent, covered with long thick black setae. Gonocoxites 11 highly sclerotized, lateral arms elongated, apex broad and curved ventrad in dorsal view. Gonostylus 11 rounded in lateral view. Gonocoxites 9 narrow and elongated, wider in lateral view with pointed apex.

Note

Myrmeleon hyalinus currently includes five subspecies: M. h. hyalinus Olivier, 1811 (widespread in Northern Africa and the Middle East, Atlantic islands, India, and Pakistan), M. h. afghanus Hölzel, 1987 ( Afghanistan), M. h. caboverdicus Hölzel, 1987 ( Cape Verde Islands), M. h. cabrerai Navás, 1912 (Canary Islands), and M. h. distinguendus Rambur, 1842 (widespread in Southern Europe to the Middle East), which can be distinguished in adult morphology and geographical distribution ( Hölzel 1987). The morphological characters to delimit the subspecies of M. hyalinus are largely unreliable, particularly the frontal and prothoracic marking patterns ( Fig. 14A–C ; Hölzel 1987: fig. 2; Akhtar et al. 2018: fig. 3a; Hajiesmaeilian et al. 2020: fig. 11). For example, the marking pattern of frons in our examined specimen is similar to M. h. cabrerai with lower margin of frons narrowly yellow ( Fig. 13B ; Hölzel 1987: fig. 10), but different from M. h. hyalinus that is distinguished by a median yellow marking on frons at lower margin ( Fig. 14B ; Hölzel 1987: fig. 8; Akhtar et al. 2018: fig. 7a; Hajiesmaeilian et al. 2020: 20). However, the intraspecific divergence herein observed for M. h. hyalinus and M. h. distinguendus was 0.021 –0.049 based on COI gene data. Furthermore, the monophyly of M. h. hyalinus was not recovered based on our analysis ( Fig. 21 ). In conclusion, a combined morphological and molecular data should be applied for all subspecies to resolve the status of these geographically isolated subspecies.

Distribution

Pakistan: (Punjab Province: District Bahawalpur, Lal Sohanra National Park); widespread: Southern Europe, Northern Africa, Middle East, East to Western India and Macaronesia ( Aspöck et al. 2001; Stange 2004; Ábrahám 2010, 2011, 2017; Akhtar et al. 2018; Hassan et al. 2019; Oswald 2020).

Figures

Fig. 12. Myrmeleon hyalinus hyalinus Olivier, 1811 (CAUPK000024). Male, dorsal habitus. Scale bar = 0.5 mm.

Fig. 13. Myrmeleon hyalinus hyalinus Olivier, 1811 (CAUPK000024). Right fore- and hind wing. Scale bar = 5.0 mm

Fig. 14. Myrmeleon hyalinus hyalinus Olivier, 1811 (CAUPK000024). A. Dorsal habitus of head and thorax. B. Head, frontal view. C. Head and pronotum, dorsal view. D. Antenna. E. Lateral view. Scale bars: A = 2.0 mm; B–D = 1.0 mm; E = 3.0 mm.

Fig. 15. Myrmeleon hyalinus hyalinus Olivier, 1811 (CAUPK000024). A. Male genitalia, lateral view. B. Same, ventral view. C. Complex of gonocoxites 9 + gonocoxites 11, dorsal view. D. Same, ventral view. E. Same, lateral view. Abbreviations: ect = ectoproct; gst11 = gonostylus 11; gx9 = gonocoxites 9; gx11 = gonocoxites 11; S = sternites; T = tergites. Scale bars = 0.5 mm.

Fig. 20. Distribution map of species of Baliga Navás, 1912 and Myrmeleon Linnaeus, 1767 from Pakistan.

Fig. 21. Phylogenetic relationships among the species of Baliga Navás, 1912 and Myrmeleon Linnaeus, 1767 from Pakistan, China, Egypt, Greece, and Japan, based on COI (A) and 16S rRNA (B) genes. The numbers at each node show the posterior probabilities and bootstrap values more than 50% in BI/ML/ NJ analysis.