Microphontes jasonlondti, Markee, Amanda & Dikow, Torsten, 2018

Markee, Amanda & Dikow, Torsten, 2018, Taxonomic revision of the assassin-fly genus Microphontes Londt, 1994 (Insecta, Diptera, Asilidae), African Invertebrates 59 (2), pp. 195-237 : 195

Microphontes jasonlondti sp. n. Figs 26-31, 58-59, 71

Microphontes whittingtoni Londt, 1994 (in part)

Etymology.

The species is named after Jason G.H. Londt who is without doubt the most knowledgeable Afrotropical Asilidae taxonomist, present and past, to recognise his contributions to the study of assassin flies and who also collected the type series. This species was unveiled at the 9th International Congress of Dipterology (25-30 November 2018) in Windhoek, Namibia during the Asilidae symposium organised in his honour entitled, "Taxonomy and phylogeny of Asilidae - honouring 40 years of Afrotropical research by Jason Londt" on 27 November 2018.

Diagnosis.

The species is distinguished from congeners by the only slightly transversely rectangular abdominal tergites, the general brown colouration and a long gonocoxite extending beyond midpoint of the epandrium (in lateral view) in the male terminalia.

Description.

Head: wider than high, brown; vertex and compound eyes at same level; facial swelling indistinct, only lower facial margin slightly developed, silver pubescent; mystax white macrosetose, restricted to lower facial margin, short, reaching tip of proboscis; ommatidia of same size; postgena posterior margin simple, smooth; frons (at level of antennal insertion) slightly diverging laterally, grey pubescent, light brown setose; ocellar tubercle greyish-brown pubescent, light brown setose; vertex brown pubescent, yellowish to light brown macrosetose; median occipital sclerite (m ocp scl) with several yellowish macrosetose; postocular (pocl) setae slightly angled anteriorly distally, yellowish macrosetae; occiput predominantly light brown pubescent, yellowish setose; compound eye posterior margin (in lateral view) straight or slightly curved throughout.

Proboscis and maxillary palpus: proboscis straight, brown; postmentum plate-like, straight, ventral margin entirely smooth, white setose ventrally; prementum circular, with dorso-median flange, asetose; labella reduced, fused to prementum only ventrally, only forming distal tip of proboscis, rounded; maxillary palpus brown, two-segmented, long yellowish setose, cylindrical; stipites fused medially, but with V-shaped indentation, apubescent, long white setose.

Antenna: light brown, lightly grey pubescent; scape 1.5 × as long as pedicel, short and long yellowish setose and macrosetose ventrally; pedicel short yellowish setose dorsally and long yellowish macrosetose ventrally; postpedicel cylindrical (same diameter throughout), approximately 2 × as long as scape and pedicel combined, asetose; stylus comprised of 1 element, 0.26 × as long as postpedicel, asetose; apical seta-like sensory element situated apically on stylus.

Thorax: brown, postpronotal lobes and lateral scutum orange to light brown; prosternum white pubescent, separated from proepisternum, square to rectangular in shape (straight dorsally); proepisternum white pubescent, long yellowish macrosetose; cervical sclerite long yellowish setose; antepronotum white pubescent, short yellowish setose medially, long and weakly yellowish macrosetose laterally; postpronotum white pubescent, long yellowish setose medially and sub-laterally, long and weakly yellowish macrosetose laterally; postpronotal lope long yellowish setose and longer yellowish macrosetose anteriorly; pleuron white pubescent; proepimeron long white setose anteriorly; anepisternum long yellowish setose dorsally (setae directed dorsally), long yellowish setose postero-medially (setae directed posteriorly), supero-posteriorly long yellowish setose (indistinguishable from other dorsal anepisternal setation); anterior basalare long yellowish setose medially, posterior basalare asetose; anepimeron asetose, katepisternum asetose, katepimeron asetose, katatergite long yellowish macrosetose, meron + metanepisternum asetose, metakatepisternum asetose, metepimeron asetose, anatergite asetose; scutum predominantly light brown pubescent, paramedian stripes and sub-lateral spots (divided by transverse suture) brown pubescent, scutum setation: long yellowish setose, setae with small sockets, 1-2 npl setae, 1 spa setae, 2 pal setae, 2-3 long yellowish postsutural dc macrosetae, acr setae long yellowish presuturally and postsuturally, median posterior scutum (between dc setae) long yellowish setose, setae directed anteriorly; scutellum grey pubescent, ds sctl setae present, long yellowish setae, ap sctl setae present, 12-16 long yellowish macrosetose; postmetacoxal area entirely membranous.

Leg: light brown to brown, apubescent, all setae circular in cross section; pro coxa brown, grey pubescent, white setose and macrosetose; pro femur orange to light brown, short white setose, white macrosetose: 2-3 postero-dorsal distally; pro tibia light brown to brown, short white setose, yellowish macrosetose: 4 in 1 antero-dorsal row, 4 in 1 dorsal row, 5 in 1 posterior row, 6 in 1 postero-ventral row, distal tip with 5-6 long yellowish macrosetae; mes coxa brown, grey pubescent, yellowish macrosetose; mes femur brown, short white setose, yellowish macrosetose: 2 anterior proximally and medially, 1 antero-dorsal distally, 2-3 posterior distally; mes tibia light brown to brown, short white setose, yellowish macrosetose: 4 in 1 anterior row, 5 in 1 dorsal row, 5 in 1 antero-ventral row, 4 in 1 posterior row, 4 in 1 postero-ventral row, distal tip with 6 long yellowish macrosetae; met coxa brown, grey pubescent, white setose and macrosetose, anteriorly without any protuberance; met trochanter yellowish macrosetose, cylindrical, medially without any protuberance; met femur brown, long white setose, yellowish macrosetose: 5 in 1 anterior row, 1 antero-dorsal sub-distally, 1 dorsal distally; met tibia brown, straight, short white setose, yellowish macrosetose: 4 in 1 anterior row, 4 in 1 antero-ventral row, 3 in 1 dorsal row, distal tip with 5 short yellowish macrosetae; proximal pro and mes tarsomere as long as following 2 tarsomeres combined, proximal met tarsomere longer than 2 following tarsomeres combined, proximal met tarsomere as wide as following tarsomeres; pro tarsomeres 1-5 white setose dorsally, tarsomeres 1-4 short yellowish macrosetose disto-laterally and disto-dorsally, tarsomere 5 weakly yellowish macrosetose distally; mes tarsomeres 1-5 white setose dorsally, tarsomeres 1-4 short yellowish macrosetose disto-laterally and disto-dorsally, tarsomere 5 weakly yellowish macrosetose distally; met tarsomeres 1-5 white setose dorsally, tarsomeres 1-4 short yellowish macrosetose disto-laterally and disto-dorsally, tarsomere 5 weakly yellowish macrosetose distally; pulvilli well-developed (as long as claw); claw abruptly angled distally, pointed; empodium setiform, approximately ½ length of claw.

Wing: 3.5-4.5 mm, stump vein ( R 3) absent, rarely present, short stump vein ( R 3) not reaching R2+3.

Abdomen: shape somewhat compressed, T2-3 transversely rectangular (length to width ratio = 1:1.5-1:2), brown, tergites smooth, setae with small sockets only; T1 yellowish setose, postero-laterally long yellowish macrosetose, grey pubescent, anterior ¼, except laterally, membranous, dorsal surface smooth, without protuberances; T2-8 entirely sclerotised, brown, grey pubescent: in dorsal view T2-3 appearing partly brown pubescent, T4-7 appearing entirely brown pubescent, in lateral view T2 appearing brown pubescent only on posterior 1/5, T3-7 appearing brown pubescent in sub-lateral triangular pattern, short yellowish setose, long yellowish setose antero-laterally on T2, marginal macrosetae absent from T2-8, medial macrosetae absent from T2-8; S1-8 brown, lightly grey pubescent, short yellowish setose.

Female: T6-7 grey pubescent, T8 apubescent, setation directed anteriorly on T6-7 and dorsally on T8; postero-paramedian T8 pores present, indistinct, opening not elevated above tergite surface; S8 plate-like, hypogynial valves separated (surrounded by membrane); T9 and T10 entirely fused, sclerites not distinguishable, T10 divided into 2 heavily sclerotized acanthophorite plates, with 6, dark brown acanthophorite spines per plate; cerci simple and flat, long yellowish setose.

Male (Figs 58-59): T1-T7 and S1-S7 entire, T8 + S8 reduced to ring of sclerites; hypopygium dark brown, rotated by 180°; hypandrium well-developed, triangular, posterior margin with long postero-median projection.

Type locality: SOUTH AFRICA: Northern Cape: Renoster River (18 km N Sutherland), 32°15'10"S, 020°41'39"E (-32.2527803, 20.69417).

Material examined.

SOUTH AFRICA: Northern Cape: 1♀ Renoster River, 24 km N Sutherland , 32°12'18"S, 020°41'41"E, 1290 m, 1998-11-11, hard earth near stream, Londt, J. (Paratype, NMSA-DIP-74485 , NMSA) ; 2♂ Renoster River, 18 km N Sutherland , 32°15'10"S, 020°41'39"E, 1290 m, 1998-11-07, Karoo macchia, Londt, J., Londt, B. (Holotype NMSA-DIP-4768 , Paratype NMSA-DIP-27120 , NMSA) ; 1♂ Williston, 10 km W , 31°21'01"S, 020°50'59"E, 1060 m, 1986-11-15, sand Acacias, Londt, J., Quickelberge, C. ( NMSA-DIP-4764 , NMSA) .

Distribution, biodiversity hotspots, phenology and biology.

Known only from three localities in the Northern Cape of South Africa (Fig. 71). A rarely collected species known only from three collecting events in 1986 and 1998 (Table 1). The species is primarily distributed in the Succulent Karoo biodiversity hotspot, but also occurs in the Nama Karoo outside of any hotspot (Fig. 71). Adult flies are active in early summer in a winter rainfall region (Table 2). Biological data available pertain to the habitat preferences. Specimen occurrence data indicate that the species occurs in habitats near rivers.

Remarks.

The male specimen from near Williston (NMSA-DIP-4764) was studied by Londt (1994) and assigned paratype status of the then newly described species M. whittingtoni . The male terminalia were dissected, but not illustrated by Jason Londt and, when we studied the specimen and terminalia attached in a micro-vial, it became clear that the male terminalia of the holotype of M. whittingtoni (NMSA-DIP-4777) do not correspond to the terminalia of this specimen. In particular, the holotype of M. whittingtoni has a short postero-median projection on the hypandrium (Fig. 66) whereas this specimen has a very long hypandrial projection (Fig. 58, see also Remarks under M. kryphios sp. n.).