Ann. Natal Mus. Vol. 38 Pages 137-157 Pietennaritzburg November. 1997 Afrotropical Asilidae (Diptera) 29. A review of the genus Saropogon Loew, 1847 (Dasypogoninae) by Jason G. H. Londt (Natal Museum, P. Bag 9070, Pietermaritzburg, South Africa) ABSTRACT The afrotropical species of Saropogon Loew are reviewed, with eight species recorded. Four of the five previously known species are redescribed (material of the fifth being unavailable for study). Three species are described as new: S. greatheadi (from Eritrea), S. kenyensis (from Kenya) and S. zinidi (from Kenya and Tanzania). A key to the species is provided. The need for a complete review of the palaearctic fauna is expressed, as this could resolve a number of taxonomic problems still relating to the afrotropical taxa. INTRODUCTION AND HISTORICAL BACKGROUND The Dasypogoninae, characterised by the presence of a spur at the apex of the prothoracic tibiae, are generally poorly represented in the afrotropics; only three genera have been recorded - Caroncoma Londt, 1980, Pegesimallus Loew, 1858, and Saropogon Loew, 1847. While Caroncoma (1 species) and Pegesimallus (44 species) were reviewed by Londt (1980), afrotropical Saropogon remain poorly understood. Saropogon Loew is one of a few asilid genera believed to have an almost cosmopolitan distribution. The major Diptera catalogues reveal the following statistics: Afrotropical """ .... """""""""""""""",, ..... ,,"""""""""""""" 5 spp. (Oldroyd 1980) Australasian""""""""""".""""""""" """""."""""."" """"". 13 spp. (Daniels 1989) Neotropical... .... """""."""""".,, .. ,, .............. ,,"""" 11 spp. (Martin & Papavero 1970) North American (Nearctic)" .. "" ... " ........ "" .... """ ... ,, 16 spp. (Martin & Wilcox 1965) Oriental """"""".""" ......... """ ........ "" .... "".""",, .. ,,""",, .. ,," ... 6 spp. (Oldroyd 1975) Palaearctic """"."""."" ... """"".""""""""""""",, .... ,,"",, ..... ,, .. ,, 66 spp. (Lehr 1988) Although a comprehensive study of all the taxa is highly desirable, this task is not within my present competence. I will, therefore, confine my attention to species which are known to occur within the Afrotropical Region (see Afrotropical Diptera Catalogue listing). As the afrotropical species of Saropogon appear to be clustered largely in the north-eastern parts of the region, adjacent to elements of the extensive palaearctic fauna, it is important to be familiar with taxa which might occur in both the north-eastern afrotropics and adjacent southern Arabian states. Unfortunately, only two major works cover such areas; the somewhat dated, but excellent work of Efflatoun (1937) on the Egyptian fauna, and the more recent monographic study of the Palestinian fauna by Theodor (1980). 137 138 ANNALS OF THE NATAL MUSEUM. VOL. 381997 The limited historical background to afrotropical Saropogon can be summarised as follows: Loew (1851) - described Dasypogon (Saropogon) melampygus on a single Syrian specimen. The species has since been shown to have a wide distribution in the afrotropics. Wulp (1899) - recorded S. melampygus and described three new species, incisuratus, pulverulentus and rubriventris, from South Yemen. Efflatoun (1937) - in his review of the Egyptian fauna described S. elbaiensis from Sudan. Hull (1962) - provided a good generic redescription and a list of all the species known to him. While he listed S. elbaiensis, and rubriventris as valid afrotropical species, he considered pulverulentus a synonym of altematus Loew and incisuratus a subspecies of eucerus (Loew), listing these two taxa together with melampygus under the palaearctic species. Hull also listed '? tragicus Wiedemann, 1828' as a possible afrotropical taxon. Oldroyd (1963) - included Saropogon in a key to the tribes and genera of African Asilidae. Oldroyd (1980) - catalogued five afrotropical species - elbaiensis, incisuratus, melampygus, pulverulentus and rubriventris. Lehr (1988) - catalogued palaearctic species and listed afrotropical records for S. elbaiensis, melampygus and vestitus (Wiedemann). This paper covers all species recorded from the Afrotropical Region except for '? tragicus Wiedemann, 1828' as listed by Hull (1962) and vestitus as listed by Lehr (1988). Wiedemann described tragicus in Dasypogon and, according to Oldroyd (1980) who listed the species under 'Unplaced Oasypogoninae', his specimen(s) were from South Africa. While I have not seen Wiedemann's material, the species is unlikely to be a Saropogon as the genus is not known to occur south of Tanzania. As far as vestitus is concerned, I have excluded it from this paper as I have not seen positively identifiable material from the afrotropics. The possibility that rubriventris is a synonym of vestitus is, however, discussed. MATERIAL AND METHODS Every effort was made to locate and examine all type specimens and all available afrotropical material. Seventy two specimens were accumulated. Institutions which provided specimens for study are listed below, together with the names of the people who kindly assisted me. BMNH The Natural History Museum, London, U.K. (J. Chainey) CASC California Academy of Sciences, San Francisco, U.S.A. (N. D. Penny) ISNB Institut Royal des Sciences Naturelles de Belgique, Brussels, Belgium (P. Grootaert) MRAC Musee Royal de l' Afrique Centrale, Tervuren, Belgium (E. De Coninck) NMKE National Museum of Kenya, Nairobi, Kenya (M. de Meyer) LONDT: THE GENUS SAROPOGON (DASYPOGONIN AE) 139 NMSA Natal Museum, Pietennaritzburg, South Africa OXUM Hope Entomological Collections, University Museum, Oxford, U. K. (Dr J. McGavin) WAAU Wageningen Agricultural University, Wageningen, The Netherlands (R. Zwart) In recording label data a standard fonnat is used, where infonnation contained on each label is demarcated by use of single inverted commas, each line of data being separated by a slash (I). Square brackets are used to indicate additional information not found on labels. In all instances specimens were dry-mounted on pins. Drawings of genitalia were prepared after first removing the tenninal segments of the abdomen and clearing them in hot potassium hydroxide. Genitalia so treated were stored temporarily in small plastic vials, containing a mixture of ethanol and glycerine, until completion of the study when they were sealed in polyethylene tubes containing a mixture of glycerine and ethanol, and attached to the specimen pins. The following notes are useful in interpreting descriptive passages: antennal setae are confined mainly to scape and pedicel, but there are also setae on the posterodorsal parts of the flagellum; widths of eye and face are measured anteriorly at the level of maximum head width; the width of eye: width of face ratio is calculated by dividing the eye width by the face width (a value greater than one indicating that the face is narrower than the eye); abbreviations used for mesonotal macrosetae are npl = notopleurals, spal = supra-alars, pal = postalars, dc = dorsocentrals (acrostichal macrosetae are absent or so poorly developed as to blend in with general fine setation); wing length is measured from humeral crossvein to tip, breadth at broadest level; proportional lengths of antennal segments are relative to the scape which is taken as 1. Tenninology generally follows McAlpine (1981). TAXONOMY Saropogon Loew Saropogon Loew, 1847: 439 (as subgenus of Dasypogon). Type-species: Dasypogon luctuosus Wiedemann, 1820. by designation ofCoquillett (1910: 603). Sarapogon: Williston, 1889: 74, incorrect spelling. Hull (1962) provided an excellent and full redescription of the genus. The following keys will separate the afrotropical taxa. Key to afro tropical genera of Dasypogoninae Prothoracic tibial spur stout and associated with a well-developed tarsal process; scutellum lacking marginal macro setae; d hypandrium fused with epandrium to fonn a continuous ring ........................................................................................... 2 Prothoracic tibial spur slender, sigmoid, and not associated with a tarsal process, but at most a group of stout, peg-like, black tarsal setae; scutellum with a pair of well-developed marginal macrosetae; d hypandrium not fused with epandrium, but separated from it by a suture .................................................. Saropogon Loew 2 Ocellar tubercle prominent; occiput usually with one pair of vertical setae not borne on a prominence; postpronotal lobe (= humeral callus) lacking 140 ANNALS OF THE NATAL MUSEUM, VOL. 381997 macrosetae; mesonotum lacking dorsocentral macrosetae anterior to transverse suture ........................................................................................ Pegesimallus Loew Ocellar tubercle not prominent; occiput with 2-3 pairs of vertical setae borne on a prominence immediately behind ocelli; postpronotal lobe with 1-2 stout macrosetae; mesonotum with well-developed dorsocentral macrosetae anterior to transverse suture ........................................................................ Caroncoma Londt Key to afrotropical species of Saropogon (excluding elbaiensis Efflatoun and vestitus (Wiedemann)) Antennal flagellum plus micro segment more than 3 times the combined lengths of scape and pedicel; pedicel approximately half the length of scape .................... . greatheadi sp. n. Antennal flagellum plus microsegment less than twice the combined lengths of scape and pedicel; pedicel and scape subequal in length ....................................... 2 2 Abdominal terga Tl-3 uniformly blackish ............................................................ 3 Abdominal terga Tl-3 yellow-brown with at most some dark red-brown parts ... .4 3 Terga T4-6 blackish, like Tl-3; wing membrane uniformly transparent, and with cell m3 open at margin; a small species (wing length about 5 mm) ........................ . incisuratus Wulp Terga T4-6 yellow-brown, contrasting with blackish Tl-3; wing membrane brown-shaded (due to presence of microtrichia) along major veins, and with cell m3 closed and stalked; a big species (wing length about 9 mm) ........... zinidi sp. n. 4 Wings yellow-brown (due to a combination of staining and the presence of microtrichia over entire membrane) ....................................................................... 5 Wings transparent (due to the complete lack of staining and the absence of microtrichia over most of the membrane) .............................................................. 6 5 Dark red-brown markings of abdomen located predominantly on anterior segments; face gold pruinose in both sexes; cell m3 usually closed ........................ . melampygus Loew Dark red-brown markings of abdomen located predominantly on posterior segments; cJ face dark red-brown pruinose, 9 face gold pruinose; cell m3 usually open ................................................................................................ kenyensis sp. n. 6 Cell m3 closed and stalked ....................................................... pulverulentus Wulp Cell m3 open at margin ............................................................... rubriventris Wulp Saropogon elbaiensis Efflatoun, 1937 Saropogon elbaiensis Eftlatoun, 1937: 394--7 figs 309-310 head, 311-312 d gen., Plate viii fig. 80 whole d; Hull, 1962: 278; Oldroyd, 1980: 367. This species was described from a short series collected during April and May 1929 at Gebel Elba (22°11'N:36°21'E) by M. Tewfik (Efflatoun 1937). While Efflatoun included the species in a review of Egyptian asilids the locality is in the north-eastern part of Sudan, close to the Egyptian border, and should therefore be included in any study of the afrotropical fauna. Both Hull (1962) and Oldroyd (1980) LaNDT: THE GENUS SAROPOGON (DASYPOGONINAE) 141 correctly dealt with the species in this way. Unfortunately the whereabouts of the type specimens is not known and so they could not be studied. In describing elbaiensis Efflatoun remarked that it was 'closely allied to S. alternatus Lw., from British Baluchistan (Quetta, 6000 ft.) but is easily distinguished from it by antennae, wing-venation and the design on the abdomen.' According to Lehr (1988), S. alternatus has been recorded from 'USSR: SMA' (Soviet Middle Asia) and Iran - some distance from Sudan. I have studied a defective specimen (lacking terminalia) from BMNH which is labelled 'Niboi / 7.vi.22'; 'Kenya Colony / Northern Frontier Dist. / Juba River. / Dr. J. O. Beven'; 'Saropogon / sp ? / near alternatus'; 'Pres. by / Imp. Inst. Ent. / Brit. Mus. /1931-138'. Kenyan gazetteers available to me do not list Juba River. The only Juba I found is in Sudan (4°S0'N:31°3S'E) and so it seems likely that this specimen may belong to elbaiensis. If this is true the specimen must be a female as the abdomen is very largely red-brown in colour (the male's being almost entirely blackish). Although this damaged specimen agrees in most respects with the description given by Efflatoun I am not entirely confident of the identification. For the present I exclude this species from my key due to the absence of good comparative material. Saropogon greatheadi sp. n. Figs I-S Etymology: Named for Dr David Greathead, whose collecting activities in north-east Africa added a number of interesting specimens to the collections of the British Museum, London. Description: Based on holotype 0. Head (Figs 1-2): Face brown-yellow, gold pruinose; frons, vertex and occiput dark red-brown to black, silver pruinose except for a transverse band across vertex, including most of ocellarium, which is shiny apruinose. Setae of frons, vertex and occiput very short and whitish. Antenna with orange scape and pedicel, dark red brown flagellum and rnicrosegment; setae mostly yellow, a few black; proportional lengths of segments - 1 : O.S : 6.0; pedicel ca half length of scape, microsegment not clearly differentiated from flagellum, subapical pit-enclosed seta present (pit far more elongate than in other species). Width of eye: width of face ratio 0.9 : 1 (i.e. face slightly wider than eye). Mystax brown-yellow and black (3 setae only); composed of 9 setae arranged in a single row along lower facial margin. Pal pus dark brown. Proboscis dark red-brown with paler transverse stripe at mid-length, very gently downcurved. Thorax: Mesonotum orange-brown with 3 dark red-brown longitudinal areas, the central one reaching to anterior margin; silver pruinose especially on lateral margins. Macrosetae brown-yellow: 3 npl; 3 spal; 2 pal; ca. 4 pairs dc postsuturally; pronotal lobes with 2 brown-yellow macro setae. Scutellum brown-yellow, 2 brown-yellow marginal macrosetae; disc asetose, silver pruinose. Pleura dark red-brown, gold-silver pruinose; katatergite with ca. 20 scattered pale yellow setae. Wing: 12.4 x 4.7 mm; cell m] closed and stalked, cup closed; membrane unstained, transparent; rnicrotrichia 142 ANNALS OF THE NATAL MUSEUM. VOL. 38 1997 5 1 mm 3-5 Figs 1-5. Saropogon greatheadi sp. n., holotype d (Massawa). 1-2. Head. I. Lateral. 2. Anterior. 3-5. d genitalia. 3. Lateral. 4. Dorsal. 5. Ventral. Scale lines equal I mm. confined to wing margins and tip as well as margins of major veins, giving these areas a grey appearance. Halter: Brown-red. Legs: Brown-yellow, tarsi slightly darker; setae yellow and black (macrosetae mostly black). Abdomen: Brown; macro setae pale yellow, confined to lateral parts of Tl. Genitalia (Figs 3-5): not rotated; proctiger well developed and downwardly directed distally; hypandrium tapering to rounded point distally and with poorly developed membranous, distal lobe (Fig. 5); phallus moderately developed with wing-like projections laterally (Fig. 5). LONDT: THE GENUS SA ROPOGON (DASYPOGONINAE) 143 Variation: The paratype d is teneral, somewhat distorted, greasy and lacking the terminal segments of the antennae. The genitalia and other main diagnostic features agree well with the holotype. The 9 is unknown. Material examined: ERITREA: 1 d hoiotype, '15 ml N Massawa [= Mits'iwa - 15°36'N:39°28'E] / Eritrea /8/8/64' (BMNH); 1 d paratype, 'Eritrea: / near / Massawa / l.iv.1961 / D. 1. Greathead' (BMNH). The holotype locality label is hand-written in pencil and was probably intended as a field label. Greathead (pers. comm.) suggests that he collected the holotype as he visited the locality in both 1961 and 1964. He describes Massawa and the collecting site as follows 'Seaport for Eritrea and northern Ethiopia on salt marsh. Collecting site inland of marsh on gravel plain with sparse grass clumps and few flowering shrublets'. Saropogon incisuratus Wulp, 1899 Figs 6-10 Saropogon incisuratus Wu1p, 1899: 82 PI. II fig. 1 (wing). Saropogon eucerus incisuratus; Hull, 1962: 278. Wulp (1899) described this species on 'five male specimens from Lahej' (13°01'N:44°54'E) collected by Col. 1. W. Yerbury in South Yemen. The OXUM has sent me four males (listed below); the whereabouts of the fifth specimen is not known. Wulp (1899) did not designate a holotype so all his specimens must be considered syntypes. I here designate the male labelled as Type Dip: 182 114 (accession number 7677) as lectotype and consider the other OXUM specimens to be paralectotypes. Wulp did not comment on the species' relationships with other taxa. Redescription: Based on lectotype d. Head (Figs 6-7): Face brown-yellow, silver-gold pruinose; frons, vertex and occiput dark red-brown to black, silver-gold pruinose except for a transverse band across vertex, including most of ocellarium, which is shiny apruinose. Setae of frons and vertex black, of occiput black and whitish. Antenna brown-yellow, slightly darker distally; setae dark red-brown; proportional lengths of segments - 1 : 2.0 : 5.5 : 0.9; microsegment with subapical pit-enclosed seta. Width of eye: width of face ratio 1.6 : 1. Mystax pale yellow-white; composed of ca. 12 setae and confined to lower facial margin. Palpus dark red-brown. Proboscis dark red-brown, straight. Thorax: Mesonotum dark red-brown, postpronotal and postalar lobes brown; fine silver pruinose, especially along lateral margins. Macrosetae pale yellow-white: 2 npl; 2 spal; 2 pal; ca. 2 pairs dc post suturally. Scutellum dark red-brown, lateral parts slightly paler, with 2 pale yellow-white marginal macrosetae; disc asetose, silver gold pruinose. Pleura dark red-brown, silver-gold pruinose; katatergite with ca. 12 scattered pale yellowish setae. Coxae as pleura but red-brown pminose. Wing: 4.8 x 1.7 mm; cells m} and cup open; membrane unstained, transparent; microtrichia confined to wing margins and tip giving these areas a grey appearance. Halter: Pale brown-yellow. Legs: Pale brown-yellow except for tarsi which are slightly darker, metathoracic femur which has a large dark red-brown patch mid-dorsally extending onto anterior and posterior surfaces, and trochanters which are dark red-brown like coxae; setae yellowish and dark red-brown, the latter mostly on tarsi. 144 ANNALS OF THE NATAL MUSEUM, VOL 381997 6-7 8 8-10 Figs 6-10. Saropogon incisuratus Wulp. 6-7. Head, lectotype r:J (Lahej). 6. Lateral. 7. Anterior. 8-10. r:J genitalia, paralectotype () (Lahej). 8. Lateral. 9. Dorsal. 10. Ventral. Scale lines equal 1 mrn. Abdomen: Dark red-brown to black, terminalia brown-orange, hind margins of T2-4 silver pruinose; macrosetae pale yellow-white, confined to lateral parts of Tl, setation white. Genitalia (Figs 8-10): rotated ca. 90° clockwise; gonocoxite with elaborate branched distal projections; hypandrium with well-developed membranous, distal lobe (Fig. 10); phallus well developed and projecting distally to be approximately level with proctiger (Fig. 8). Variation: Paralectotypes concur remarkably with the lectotype. The 9 of this species has not been identified (although it is possible that the unique 9 of rubriventris may be con specific - see discussion below). Material examined: Types (OXUM): SOUTH YEMEN: 1 d lectotype, 'Type / v.d. Wulp / Trans. Ent. Soc. /1899, page 82/ pI. ii, fig. 1' ; 'So W. Arabia /15 miles N. W. of / Aden, Lahej / Capt. Mar. 28.95 [1895] by / J. W. Yerbury'; '1899/7677'; 'Type Dip: 182 114 / Saropogon / incisuratus / van der Wulp / Hope Dept. Oxford'. 3 d paralectotypes same data but Mar. 10.95, 189917681 (Type 182 2/4), Mar 5.95, LONDT: THE GENUS SAROPOGON (DASYPOGONINAE) 145 189917680 (Type 1823/4), Mar. 17.95, 189917678 (Type 1824/4). Relationships: While Hull (1962) considered incisuratus to be a subspecies of eucerus (Loew), this combination was not accepted by Oldroyd (1980). A decision on this matter can only be made after taxonomic review of the palaearctic fauna. For the present incisuratus appears to be a distinctive species within the afrotropical fauna. The open cell m3 suggests affinity with rubriventris (see below) and possibly kenyensis. Saropogon kenyensis sp. n. Figs 11-15 Etymology: Named after Kenya, from which all known material has been collected. Description: Based on holotype d. Head (Figs 11-12): Entirely dark red-brown to black; face brown-red pruinose, frons, vertex and occiput silver pruinose except for most of ocellarium, which is shiny apruinose. Setae of frons, vertex and occiput white. Antenna orange; setae pale yellow; proportional lengths of segments - 1 : 1.2 : 2.7 : 0.2; microsegment with subapical pit-enclosed seta. Width of eye : width of face ratio 1.3 : 1 (Le. face somewhat narrower than eye). Mystax pale yellow-white; composed of ca. 60 setae arranged in 3 rows along lower facial margin. Palpus dark red-brown. Proboscis dark red-brown, gently downcurved distally. Thorax: Mesonotum dark red-brown, postpronotal and postalar lobes brown-orange; silver pruinose especially on lateral margins. Macrosetae yellow: 2 npl; 2 spal; 2 pal; ca. 2 pairs dc postsuturally; pronotal lobes equipped with 4 yellow macrosetae. Scutellum dark red-brown with orange border, 2 yellow marginal macrosetae; disc asetose, silver pruinose. Pleura dark red-brown, gold-silver pruinose; katatergite with ca. 12 scattered pale yellow setae. Wing: 6.9 x 2.6 mm; cell m3 open, cup closed at margin; membrane yellow stained, opaque; microtrichia cover entire wing except for alula and base of anal cell (wings have an overall yellow-brown appearance). Halter: Pale yellow. Legs: Pale brown-yellow, anteroproximal parts of pro- and mesothoracic femora red-brown; macrosetae mostly yellow, but some red-brown. Abdomen: Brown-orange with dark red-brown areas as follows - entire Tl except for small lateral areas, anterodistal half of T2, anterodistal one-third of T3, lateral spots on T2-5 (terminal segments cleared for genital illustration); macrosetae pale yellow, confined to lateral parts of Tl. Genitalia (Figs 13-15): not rotated; hypandrium rounded distally, with flat membranous projection between gonocoxites (Fig. 15); phallus well developed, downtumed distally (Fig. 13). Variation: The males listed below agree well with the holotype. The abdomen may be more extensively dark red-brown; the anterior faces of the metathoracic femora may be partly dark red-brown; cell cup may be narrowly open at the wing margin. There appears to be some sexual dimorphism as the single female paratype has a bright gold pruinose face and mesonotum. Material examined: KENYA: 1 d holotype, 'Kenya 6 km S Kapedo 1 Hot waterfall 760m 1 01 °08'N:36°06'E 1 2-3.vi.1980 B. Lamoral 1 Malaise trap.'; 'Saropogon d 1 ? 146 ANNALS OF THE NATAL MUSEUM, VOL. 381997 11-12 13-15 Figs 11-15. Saropogon kenyensis sp. n. paratype d (Tsavo) 11-12. Head. 11. Lateral. 12. Anterior. 13-15. d genitalia. 13. Lateral. 14. Dorsal. 15. Ventral. Scale lines equall mm. melanopygus Lw. / det. J.G.H. Londt, 1992' (NMSA); 1 d paratype, 'Kenya / near Archer's / Post [0039'N:37°41'E] / 20.ii.1964 / D. J. Greathead' (BMNH); 2 d I 9 paratypes, 'Kenya: Tsavo Nat. / Park. Kitani Lodge [3°00'S:3rS9'E] / 2600' 6.xii.1969 / M. E. Irwin & / E. S. Ross' (CASC). Biological notes: Greathead (pers. comm.) describes Archer's Post as 'Waterhole on dirt road to Ethiopia. Open sandy savanna with scattered Acacia spp. and low shrubs'. Relationships: The species cannot be confused with any other afrotropical species. S. kenyensis is similar to melampygus in that the wings are brown-stained and entirely covered with microtrichia, but is otherwise easily separated from that taxon. It appears that the open condition of cell m3 is a stable character state shared only with incisuratus and rubriventris, species otherwise differing from kenyensis.