Syngenes medialis, Mansell, 2018

Mansell, Mervyn W., 2018, Antlions of southern Africa: Syngenes Kolbe, 1897, with descriptions of two new species and comments on extra-limital taxa (Neuroptera: Myrmeleontidae: Acanthaclisini), Zootaxa 4497 (3), pp. 346-380 : 355-362

Syngenes medialis sp. nov.

Figs 25–43 , 68 , 70 , 72 .

Etymology. Derived from its geographic distribution between the populations of S. scholtzi n. sp. in the west and S. longicornis in the east of southern Africa and in the middle of the distribution of Syngenes species extending from West Africa to Madagascar.

Description. Based on holotype male, 14 male and 61 female paratypes.

Diagnosis. Distinguished from other Syngenes species by the absence of biaereolate cells in the costal area before Rs and usually beyond Rs2 ( Figs 27 , 70 ). Wings broad, variously marked, sometimes with distinct large spots at hind margin of forewing. Abdomen banded, no chevron pattern. Tibial spurs in forelegs slender, strongly bent but not right-angular with very narrow flange, not expanding apically as in S. longicornis , hind tibial spurs evenly curved, without flange, TA 1–4 uniformly black, T5 pale. Labial palp with short slit-shaped palpimacula ( Fig. 41 ).

Head: wider than prothorax, vertex slightly raised, rounded. Frons and vertex black with short white recumbent setae; three large laterally-elongated embossed yellow marks present on upper frons, vertex with small irregular yellow spots, occiput with three distinct embossed orange patches. Face below antennae, clypeus, genae and labrum uniformly yellow, with long, sparse, pale setae. Antennae long, clavate, longer than twice head width, toruli less than scape diameter apart, scape almost touching eyes, scape and pedicel uniformly yellow, with sparse long white setae, flagellomeres short, annulated with black and yellow, covered in short black setae. Eyes large, greater than hemispherical, sparse ocular setae usually present. Maxillary and labial palps short, much less than head width, yellow, terminal labial palpomere spindle shaped with long acute apex, palpimacula short, slit shaped ( Fig. 41 ).

Thorax: yellow with black markings, sparsely pilose. Prothorax slightly longer than wide, tapering anteriorly, lateral margins with two curved black streaks that merge anteriorly and posteriorly, central pronotum with single streak at anterior margin and two short parallel streaks posteriorly, with distinct black dots at setal bases. Sparse long white and black forwardly curved setae present laterally, short black bristles along anterior raised margin, posterior margin with long curved black setae. Mesothorax: mesoprescutum yellowish-brown, black anteriorly and laterally, with two yellow spots laterally, anterior margin with long curved black setae; mesoscutum yellowishbrown with three diffuse longitudinal black lines on either side above wing bases, with sparse black setae; mesoscutellum yellowish-brown with two curved black marks centrally, anterior and lateral margins narrowly black. Metathorax: metaprescutum black with pale midline, metanotum yellow with black V-shaped mark centrally, a black streak present laterally above wing bases, velvety spots not discernible, long curved white setae present laterally; metascutum black with three yellow spots, one centrally, two laterally. Pleurites below wings yellow with black streaks, sternites yellow, dense long white setae present on pleurites and sternites.

Wings: broad, forewings longer, broader than hind wings, apices sub-acute, forewings more rounded than hind wings, membrane largely hyaline, veins with alternating sections of yellow and black, bearing very short sparse black and yellow setae on correspondingly coloured areas. Forewings broad with slightly undulating posterior margin, a distinct curved mark present in distal third, frequently with one or two large spots at posterior margins (22 of 75 specimens). Axillary protuberance at base of forewing dark yellow with long dense white and black setae. Costal vein alternating yellow and black with tuft of short black bristles at base, costal area narrow at base, broadening then narrowing slightly towards pterostigma Proximal costal area veins bifurcate but mainly unbranched, with no biaereolate cells; cells only becoming irregularly biareolate beyond Rs and usually beyond Rs2 ( Fig. 27 ). Pterostigma white. Apical margin of wing with densely arranged narrowly forked veins. Hypostigmatic cell elongate. Sc, R and proximal region of CuA with yellow and black chevron-like pattern. Membrane between Sc and R heavily marked with alternating yellow and black bands. Rs arises well beyond CuA fork, with Rs2 at or just beyond first fork of Rs, 8–10 presectoral veins present. Mp2 (oblique vein) arising beyond CuA fork, CuP arises at basal crossvein, bifurcating after short free base with upper branch linking with CuA and lower uniting with A1, A2 not parallel to A1, evenly curved. Membrane at posterior base with long soft white setae. Hind wings narrower than forewings, lanceolate, with faint marks usually discernible in distal half, axillary protuberance at base yellow with long dense white setae, C yellow and black, costal area uniareolate, veins unbranched until pterostigma, costal area narrow at base expanding into a bulge then narrowing and parallel to Sc. Pterostigma white, hardly discernible. Hypostigmatic cell long. Usually 5–6, presectoral crossveins, Rs arises beyond Mp2 fork, Cu fused with posterior branch of Mp2 fork, anterior banksian line visible in distal portion of wing. Pilula axillaris in males conspicuous, bearing densely packed short brown recumbent setae. Females with long white setae in this position.

Legs: forelegs strongly developed with short stout spines. Coxa, trochanter yellow with long white pubescence.

Femur yellow with diffuse brown marks dorsally, very stout, thickened at base tapering distally, two femoral sense hairs present near base, ventral surface with two rows of strong short black bristles accommodating the tibia on closure, long white setae occur laterally. Tibia slender, yellow with four black stripes at femoral articulation and two black annulations proximally; lateral surfaces with long white setae, black setae dorsally, with densely arranged short black setae ventrally that fit between two rows of black bristles on femur. A dense facial brush of short golden pubescence present on interior and ventral apical surfaces. Tibial spurs ( Figs 28, 29 ) slender, strongly bent but not right-angular with slightly raised flange. Tarsus with Ta5 longer than Ta1–Ta4 combined, Ta1–Ta4 shiny black, covered in short black bristles, Ta5 long, yellow, black apically, covered with short black bristles, preapical claws dark reddish-brown, stout, strongly curved. Middle legs shorter, more slender than forelegs, entirely yellow. Coxa, trochanter shorter than in foreleg, yellow with long white pubescence. Femur yellow with one sensory seta proximally, two rows of black bristles ventrally as in foreleg, covered with long white setae and sparse patch of long black bristles dorso-apically. Tibia, tarsus as in forelegs, but spurs more evenly curved lacking raised flange. Hind legs long slender, yellow, lacking femoral sense hair. Coxa, trochanter as in middle leg. Femur with faint black diffuse black stripe laterally, dorsal surface with short black setae, laterally with long black curved setae, long white setae proximally, ventral surface with two rows of short black bristles, tibia yellow, slender with short coarse black setae, tibial spurs slender, gently curved.

Abdomen: yellow with medially divided black bands at distal half of each segment ( Fig. 30 ), tergites with sparse short black setae, sternites yellow with sparse short white setae but sternites 1–2 with long soft dense white pubescence, sternite 8 black proximally, sternite 9 black. Males with black hair pencils between segments 6 and 7 ( Fig. 32 ). Male ( Figs 31–37 ): T9 yellow divided dorsally; S9 black, short, rounded with pale central stripe and long black posteriorly directed setae ( Fig. 33 ). Ectoprocts yellow with long postventral lobe, dorsal margin with black stripe ( Figs 31, 32 ), postventral lobes with long anteriorly curved white and black setae becoming longer posteriorly ( Figs 31–33 ). Gonarcus ( Figs 34–37 bears a prominent beak-shaped Mu; Pa ( Figs 34–37 ) sclerotized, articulating with Gs, terminating in upwardly curved sharply pointed extremities. Female ( Figs 38–40 , 42 ): T9 divided dorsally, Ga digitiform with long pale setae; Gl clavate bearing very long stout, slightly curved brown spines, Epr rounded, bearing slender, slightly curved setae. Spermatheca ( Fig. 42 ) very long relative to other taxa, sclerotized, broad proximally becoming slender, with long convoluted, coiled distal portions bearing fine setae along distal extremity.

Larva. Very similar to that of S. longicornis , being white with the characteristic black markings. Unfortunately, the four specimens received in the larval stage pupated before photographs or measurements could be obtained. They were collected in the sand of a dry riverbed.

Distribution ( Fig. 72 ). This species is widespread in the eastern and northern provinces of South Africa: Limpopo, Mpumalanga, KwaZulu-Natal, extending south to the Eastern Cape. Also northwards into Botswana, Mozambique, Zimbabwe, northern Namibia, Malawi, Congo and Tanzania.

Comments. Syngenes medialis resembles both S. inquinatus from West Africa and S. maritimus from Aldabra Island and Madagascar, and it was uncertain as to which of these two taxa this common and widespread species should be assigned. Examination of 76 specimens, extending over a wide area from Brazzaville ( Congo) to South Africa has however, revealed a consistent feature in which the costal veins of S. medialis are either simple or forked, without any biaereolate cells before the origin of Rs, and usually also beyond Rs2. By contrast, S. inquinatus and S. maritimus have a variable number of crossveins before Rs and biaereolate cells after Rs before Rs2. It was consequently decided to allocate separate specific status to avoid an incorrect association with either. It is clear that these three morphologically similar taxa constitute a species complex, with S. inquinatus occurring in West Africa, S.maritimus inhabiting Madagascar and Aldabra Island while S. medialis occupies a large area in between, in southern, eastern and central Africa. A specimen in MRAC labeled as Cotype of S. dolichocercus by Navás (1925) is S. medialis .

Type material examined. SOUTH AFRICA , Limpopo Province: Holotype ♂, Makhutsi Camp, Lekgalameetse Nature Reserve, 24°11’57”S 30°20’22”E, 1200m, 9.i.1997, hand-netted, M.W.Mansell, NEUR09562 . Paratypes: 2♂ 3♀, same data as holotype ; 1♀, Nylstroom , 24°42’S 28°20’E, 15.iii.1978, S.J.van Tonder, NEUR11818 ; 1♀, 10 km N Wyllies Poort , 22°53’S 29°52’E, 30.xii.1978, L.R.Minter, NEUR09075 ; 1♂ 1♀, Mogol Nature Reserve , 23°58’S 27°45’E, 20.i.1983, M.W.Mansell, NEUR00118 ; 1♀, D’Nyala Nature Reserve , 23°45’03”S 27°49’32”E, 893m, 8.xii.1989, M.W.Mansell, H.&U.Aspöck, NEUR01314 ; 1♀, same locality, 13.i.1991, E.Grobbelaar, NEUR10482 ; 1♀, Lapalala Nature Reserve School , 23°54’06”S 28°17’31”E, 1158m, 18.ii.1994, R.G.Oberprieler, NEUR11868 ; 1♀, Natuurpraal Resort, Melkrivier, 24°00’S 28°25’E, 1100m, 20.ii.1995, M.W.Mansell, H.&U.Aspöck, NEUR02038; 1 ♀, Messina , 22°19’41”S 30°01’37”E, 525m, 22.xi.1996, C.Peyper, NEUR10178 ; 1♀, Ben Lavin Nature Reserve , 23°09’S 29°57’E, 19.i.1998, M.D.Picker, NEUR09583 ; 1♀, Alldays , 22°40’S 29°06’E, 8.iii.2000, R.D.Stephen, NEUR05580 ; 1♀, Mapungubwe , 22°12’09”S 29°21’50”E, 518m, 22.xii.2009, No collector name, NEUR11867 ; 1 ♂, Dongola Ranch , 22°13’57”S 29° 41’19”E, 630m, 23.xii.2009, No collector name, NEUR11866 ; 1♀, Northwich Game Farm , 22°53’21”S 29°52’25”E, 836m, 19.i.2014, D.K.Bakkes, NEUR11922 ; 1♀, Bievack 14 Farm , 22°28’20”S 28°55’14”E, 636m, 22.iii.2014, D.Kamffer, NEUR11900 ; 1♀, Zuurfontein Farm , 23°48’29”S 27°46’27”E, 835m, 28.iii.2014, N.J.Parry, NEUR11885 ; 1♂, Gnu Ranch , 24°01’44”S 27°29’13”E, 998m, 19.iv.2014, R.W.Mansell, NEUR11878 . Mpumalanga Province: 1♀, Louws Creek , 25°37’S 31°16’E, 15.iii.1920, A.Rob, TMSA00889 , ( TMSA) ; 1♂ 3♀, Ngweti River , 25°31’S 31°42’E, 8.xi.2001, G.Nelson, NEUR05752 .

KwaZulu-Natal: 1♀, Lake Sibaya , 27°22’04”S 32°42’56”E, 50m, 15.xii.1968, J.L.Minshull, NEUR11854 ; 1♀, Empangeni , 28°44’S 31°53’E, 22.xi.1989, P.E.Reavell, NEUR11901 .

Eastern Cape Province: 1♀, Kei Bridge, 32°30’23”S 27°58’45”E, 3.iv.1990, N.J.Duke, NEUR11832 . Kruger National Park : 1♀, Satara Camp, 24°23’40”S 31°46’40”E, 269m, 1.iii.1968, A.C.Kemp, NEUR11852; 1♀, same locality and collector, 9.ii.1969, NEUR11851 ; 1♀, same locality and collector, 15.ii.1969, NEUR11850 ; 1♀, same locality and collector, 11.iii.1969, NEUR11849 ; 1♀, same locality, 26.iv.1969, J.H.Potgieter, A.Strydom, TMSA00890 ( TMSA) ; 1♀, same locality, 1.ii.1987, A.J.van Rensburg, NEUR11872 ; 1♀, same locality, 5.ii.1988, M.D.Picker, NEUR11831 ; 1♀, Crocodile Bridge, 25°21’S 31°54’E, 12.iv.1969, A.Braack, NEUR11848; 1♀, Skukuza, 24°59’41”S 31°36’49”E, 17.xii. 1970, 300m, A.Braack, NEUR11846; 1♀, same locality and collector, 7.i.1972, NEUR11855 ; 1♀, same locality and collector, 9.iii.1972, NEUR11856 ; 1♀, same locality, 14.i.1985, M.W.Mansell, NEUR11817 ; 1♀, same locality, 4.iv.1990, L.E.O.Braack, NEUR05636 ; 1♀, same locality, 26.xi.1993, M.Krüger, TMSA00891 ( TMSA) ; 1♀, same locality, 7.iv.1999, H.Stapelberg, NEUR11871 ; 5♂ 3♀, Sabi-Sand Rivers Junction, 24°57’28”S 31°42’30”E, 238m, 20.i.1984, hand-netted, M.W.Mansell, NEUR00409; 1♀, Shirombe Pan, 22°44’S 31°24’E, 19.xii.1970, A.&H.Braack, NEUR11859; 1♀, Pumbe Picket, 22°37’S 31°16’E, 7.iv.1972, A.Braack, NEUR11857; 1♀, Pafuri, 22°25’52”S 31°12’45”E, 216m, 20.xi.1973, J.van Reenen, TMSA00888 (TMSA); 1♀, same locality, 15.i.1982, R.M.Miller, NEUR11838 ; 1♂, same locality, 27.xii.1983, L.E.O.Braack, NEUR00320 ; 1♀, same locality and collector, 25.iv.1984, NEUR00327 ; 1♀, Nyandu Sandveld, 22°39’S 31°21’E, 25.xi.1973, A.&H. Braack, NEUR11845; 1♀, Bobomene, 22°25’45”S 31°12’31”E, 124m, 17.iii.1974, A.Braack, NEUR11847; 1♀, same locality, 29.i.1984, M.W.Mansell, NEUR00267 ; 1♀, Magaludzo, 22°30’45”S 31°05’09”E, 317m, 25.xi.1969, A.Braack, NEUR11858; 1♀, same locality, 1.i.1970, A.&H.Braack, NEUR11844 ; 1♀, Tambotie Camp, 24°27’16”S 31°24’21”E, 426m, 20.iv.2017, H. de Klerk, NEUR12444.

BOTSWANA: 1♀, Chobe Safari Lodge , 17°48’21”S 25°08’46”E, 940m, 1.iv.1988, A.Kvist, NEUR11843 ; 1♂ 1♀, Moremi Gorge , 22°37’S 27°26’E, 23.xii.2000, A.J.Gardiner, NEUR08976 .

CONGO: 1♀, Brazzaville , 04°16’S 15°17’E, 15.iii.1965, L.Detaille, NEUR11903 .

NAMIBIA: 1♀, Buffalo Camp , 18°07’06”S 21°40’43”E, 29.ii.1992, R.G.Oberprieler, NEUR11819 ; 1♂, Katima Mulilo , 17°30’13”S 24°16’30”E, 950m, 20.xii.2002, H.Bodenstein, NEUR06068 .

TANZANIA: 1♀, Moba , 07°02’22”S 29°45’58”E, 782m, 15.iv.1954, H.Bomans, NEUR11902 .

ZIMBABWE: 1♀, Kariba Campsite , 16°31’S 28°50’E, 27.xii.1975, M.W.Mansell, NEUR11853 ; 1♀, Tashinga Camp , 16°48’48”S 28°26’26”E, 8.iv.1988, A.J.Gardiner, NEUR01298 ; 1♀, Matsheumhlope , Bulawayo, 20°10’S 28°43’E, 11.ii.2000, A.J.Gardiner, NEUR05775 . (All in SANC except where otherwise indicated).

Figures

FIGURE 72. Recorded distribution of Syngenes species in southern Africa. Map: C. Deschodt.

FIGURES 25–26. Syngenes medialis n.sp. 25, Holotype male, NEUR09562 (Forewing length 47mm); 26, Paratype female NEUR11845 (Forewing length 47mm), showing variability in wing markings.

FIGURES 27–30. Syngenes medialis. 27, Holotype base of forewing, NEUR09562, showing absence of biaereolate cells to beyond Rs2; 28, foreleg tibial spurs and facial brush; 29, hind leg tibial spurs; 30, abdominal pattern, NEUR11845.

FIGURES 31–33. Syngenes medialis. Male terminalia. 31, lateral; 32, dorsal with hair pencils; 33, ventral.

FIGURES 34–37. Syngenes medialis. Male gonarcus and parameres complex: 34, lateral; 35, dorsal; 36, ventral; 37, caudal.

FIGURES 38–40. Syngenes medialis. Female terminalia: 38, lateral; 39, ventral; 40 dorsal.

FIGURES 41–43. Syngenes medialis. 41, labial palp with palpimacula; 42, spermatheca NEUR11818; 43, living female specimen NEUR12444. Photo: H. de Klerk©.

FIGURES 66–68. Syngenes species. Comparative lateral gonarcus and parameres complex: 66, S. longicornis; 67, S. scholtzi; 68, S. medialis.

FIGURES 69–71. Syngenes species. Comparative wing venation of Holotypes: 69, S. longicornis; 70, S. medialis; 71, S. scholtzi.