Microphontes kryphios, 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 kryphios sp. n. Figs 32-37, 68-70, 71

Microphontes whittingtoni Londt, 1994 (in part)

Etymology.

Greek kryphios = hidden, secret. Refers to the fact that this species was hidden amongst the type series of M. whittingtoni .

Diagnosis.

The species is distinguished from congeners by the small size with a wing length of 3-4 mm, distinctly wider than long and transversely rectangular abdominal tergites, partly macrosetose postpronotal lobes, setose dorsal and posterior anepisternum and features of the male terminalia such as the long postero-median projection on the hypandrium and shape of the gonostyli.

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, yellowish setose; ocellar tubercle greyish-brown pubescent, light brown setose; vertex greyish-light 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 grey 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: orange, lightly grey pubescent; scape approximately as long as pedicel, short and long yellowish setose and macrosetose ventrally; pedicel short yellowish setose ventrally and dorsally; postpedicel cylindrical (same diameter throughout), approximately 2 × as long as scape and pedicel combined, asetose; stylus comprised of 1 element, 0.15 × as long as postpedicel, asetose; apical seta-like sensory element situated apically in cavity on stylus.

Thorax: light brown, scutum with median longitudinal stripe and shorter sublateral longitudinal stripes 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 white to greyish pubescent, scutum setation: long yellowish setose, setae with small sockets, 1 npl setae, 1 spa setae, 1-2 pal setae, 2-3 long yellowish postsutural dc macrosetae, rarely 3-4 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 white pubescent, ds sctl setae present, long yellowish setae, ap sctl setae present, 6-10 long yellowish macrosetose; postmetacoxal area entirely membranous.

Leg: orange to light brown, apubescent, all setae circular in cross section; pro coxa orange to light brown, white pubescent, white setose and macrosetose; pro femur orange to light brown, short white setose, white macrosetose: 2-3 postero-dorsal distally; pro tibia orange to light brown, short white setose, yellowish macrosetose: 5 in 1 antero-dorsal row, 4 in 1 dorsal row, 5 in 1 postero-ventral row, distal tip with 1-2 long yellowish macrosetae; mes coxa orange to light brown, white pubescent, white macrosetose; mes femur orange to light brown, short white setose, yellowish macrosetose: 2 anterior proximally and medially, 2-3 anterior distally, 4 posterior distally; mes tibia orange to light brown, short white setose, yellowish macrosetose: 4 in 1 dorsal row, 5 in 1 antero-dorsal row, 4 in 1 antero-ventral row, 5 in 1 postero-ventral row, distal tip with 5 long yellowish macrosetae; met coxa orange to light brown, white pubescent, white setose and macrosetose, anteriorly without any protuberance; met trochanter yellowish macrosetose, cylindrical, medially without any protuberance; met femur orange to light brown, short white setose, yellowish macrosetose: 6 in 1 anterior row, 6 in 1 antero-ventral row, 3-4 long in 1 postero-ventral row, 1 distal dorsally; met tibia orange to light brown, straight, short white setose, yellowish macrosetose: 4 in 1 anterior row, 4 in 1 antero-ventral row, 5 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: 3.0-4.0 mm.

Abdomen: shape compressed, T2-3 distinctly transversely rectangular (length to width ratio> 1:3), orange to light brown, tergites smooth, setae with small sockets only; T1 white setose, postero-laterally long white macrosetose, white pubescent, anterior ½, except laterally, membranous, dorsal surface smooth, without protuberances; T2-8 entirely sclerotised, orange to light brown, white pubescent: in dorsal view T2-5 appearing predominantly apubescent except laterally, T6 appearing apubescent only medially, T7 white pubescent, in lateral view T2-7 appearing apubescent in posterior ¼ except lateral margin, short white setose, long white setose antero-laterally on T2, marginal macrosetae absent from T2-8, medial macrosetae absent from T2-8; S1-8 orange to light brown, lightly grey pubescent, short white setose.

Female: T6-7 predominantly grey pubescent, T8 apubescent medially and posteriorly, setation directed anteriorly on T6-7 and dorsally on T8; postero-paramedian T8 pores present, indistinct, opening not elevated above tergite surface; T10 divided into 2 heavily sclerotised acanthophorite plates, with 7-8, light brown acanthophorite spines per plate.

Male (Figs 68-70): T1-T7 and S1-S7 entire, T8 + S8 reduced to ring of sclerites; hypopygium orange to light brown, rotated by 180°; hypandrium well-developed, triangular, posterior margin with long postero-median projection.

Type locality: SOUTH AFRICA: Northern Cape: Kookfontein river (23 km N Middelpos), 31°44'00"S, 020°14'00"E (-31.73333, 20.23333).

Material examined.

SOUTH AFRICA: Northern Cape: 1♀ 1♂ Kookfontein river, 23 km N Middelpos , 31°44'00"S, 020°14'00"E, 1170 m, 1990-11-29, Whittington, A., Londt, J. (♂ Holotype NMSA-DIP-74620 , ♀ Paratype NMSA-DIP-4775 , NMSA) ; 1♀ 1♂ Calvinia, 12 km S , 31°34'10"S, 019°43'56"E, 1080 m, 2002-09-07, sandy roadside, Londt, J. (pinned in copula NMSA-DIP-4766 , NMSA) .

Distribution, biodiversity hotspots, phenology and biology.

Known from three nearby localities in the Northern Cape of South Africa (Fig. 71). A rarely collected species known only from three collecting events (Table 1). Adult flies are active in early summer in a winter rainfall region (Table 2). The species occurs within the Succulent Karoo biodiversity hotspot, but also outside of it in the Nama Karoo biome. Biological data available pertain to the mating position and habitat preferences. A pair has been collected in copula (NMSA-DIP-4766) and remarkably the flies remained in the copulation position after capture in a tail-to-tail position. Specimen occurrence data indicate that the species prefers sandy habitats along rivers.

Remarks.

The holotype and paratype of M. kryphios sp. n. were studied by Londt (1994) and assigned paratype status of the then newly described species M. whittingtoni . The male holotype of M. kryphios sp. n. was dissected and the male terminalia illustrated by Jason Londt (see Figs 68-70) to represent M. whittingtoni . 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 illustrations published in figures 51-53 by Londt (1994), which were based on the 23 km N Middelpos specimen that we assign to be the holotype of M. kryphios sp. n. In particular, the holotype of M. whittingtoni has a short postero-median projection on the hypandrium (Fig. 66) whereas the holotype of our new species M. kryphios sp. n. has a very long hypandrial projection (Fig. 68, see also Remarks under M. jasonlondti sp. n.).