CLUSIIDAE (Druid flies) 81

Transcription

1 SURICATA X (20XX) 10 CLUSIIDAE (Druid flies) 81 Owen Lonsdale Fig Male of Heteromeringia sp. (non-afrotropical) (photograph S.A. Marshall). Diagnosis Small-sized, relatively slender acalyptrate flies (Fig. 1) (body length: ca mm), with anterodistal margin of wing often infuscated and colouration varying from mainly black and brown (many Czernyola Bezzi and Heteromeringia Czerny), to almost entirely yellow or white (some Sobarocephala Czerny), but often with brown pattern on yellow background. Pedicel with angular process on outer and sometimes inner margins. Head with antenna porrect; pedicel with angulate extension on outer and sometimes inner margins; arista dorsoapical (not dorsobasal) (Figs 11, 12); face often soft and flat, sometimes lightly sclerotised, with dorsomedial surface produced as a shallow carina or bulge (Figs 8 10); 1 pair of pronounced vibrissae; ocellar and postvertical setae divergent when present; 2 5 fronto-orbital setae, if all setae reclinate, then either with (Hendelia Czerny) (Fig. 10) or without (Allometopon Kertész) interfrontal seta; anterior fronto-orbital seta sometimes inclinate (Sobarocephalinae, Clusiinae, Heteromeringia) (Fig. 8); if 4 or 5 setae present, then third posterior seta sometimes inclinate (Czernyola) (Fig. 9). Thorax with 1 pronounced katepisternal and anepisternal seta; usually 2 or 3 dorsocentral setae; prosternum setulose. Legs with dorsal preapical tibial seta absent (Allometopon, Heteromeringia, Tetrameringia McAlpine), present on mid leg (Sobarocephala), or present on both mid and hind legs (Czernyola, Hendelia). Wing with subcosta complete (Fig. 2); 1 costal break near insertion of subcosta (sometimes difficult to see in Clusiodinae); vein CuA2 complete, enclosing cell cup (anal cell); wing often infuscated, at least anterodistally (Figs 1 7); vein A1+CuA2 well-developed. Abdomen with male sternites 6 and 7 variably developed and left lateral to ventral; sternite 8 well-developed, dorsal to Kirk-Spriggs, A.H. & Sinclair, B.J. (eds) Manual of Afrotropical Diptera. Volume 2. Suricata XX. Pretoria: SANBI Publishing.

2 SURICATA X (20XX) right lateral; sternites 6 8 fused anteriorly, at least along left lateral margin, often forming a complete ring through ventral fusion of sternites 6 and 8 (Figs 14, 23); tergite 7 small when present, forming sclerotised patch around right spiracle 7; female sternite 8 sometimes entire (Figs 37, 39), but usually apically bilobed and longitudinally divided (Fig. 35). Some Chloropidae (see Chapter 96), Lauxaniidae (see Chapter 74), Psilidae (see Chapter 65) and non-afrotropical Richardiidae have a superficially similar habitus and colouration, but these are otherwise readily differentiated. Other similarly narrow-bodied acalyptrates lack an angular projection on the antennal pedicel, 11 with the following exceptions: Neriidae (see Chapter 63) have an extension only on the inner surface of the pedicel, but these are larger flies with veins R4+5 and M1 convergent; Anthomyzidae (see Chapter 87) have the outer surface of the pedicel shallowly angulate, but the antenna is slightly elbowed, the postocellar setae are convergent or absent, the subcostal is incomplete and the fore femur usually has a ctenidial seta; Aulacigastridae (see Chapter 88) have extensions on both sides of the pedicel, but the inner process is more prominent and the subcostal is incomplete; Neminidae (see Chapter 89) also have a process only on the inner surface of the pedicel, but the anepisternal seta is highly reduced to absent and the subcosta is incomplete. Figs Wings of Clusiidae (dorsal views): (2) Sobarocephala sp.; (3) same, Tetrameringia sp.; (4) same, Allometopon sp.; (5) same, Hendelia sp.; (6) same, Czernyola sp.; (7) same, Heteromeringia sp. Abbreviations: A1+CuA2 first branch of anal vein + second branch of anterior branch of cubital vein; bm basal medial cell; CuA1 first branch of anterior branch of cubital vein; cup posterior cubital cell; dm discal medial cell; dm cu discal medial cubital crossvein; M1 first branch of media; R1 anterior branch of radius; R2+3 second branch of radius; R4+5 third branch of radius; r m radial medial crossvein; Sc subcosta. CLUSIIDAE (DRUID FLIES) 81

3 12 SURICATA X (20XX) Figs Heads and antennae of Clusiidae (laterodorsal views): (8) head of Heteromeringia sp.; (9) same, Czernyola sp.; (10) same, Hendelia sp.; (11) antennae, outer surface of Heteromeringia sp. (arista omitted); (12) same, Tetrameringia sp. (arista omitted). Abbreviations: ar arista; flgm 1 first flagellomere; frorb s fronto-orbital seta; i vt s inner vertical seta; infr s interfrontal seta; o vt s outer vertical seta; ped pedicel; poc s postocellar seta; scp scape; vb vibrissa. MANUAL OF AFROTROPIAL DIPTERA VOLUME 2

4 SURICATA X (20XX) 13 Figs Male terminalia of Clusiidae: (13) hypandrial complex of Sobarocephala zuluensis Stuckenberg, lateral view; (14) same, external components, lateral view; (15) same, posterior view; (16) hypandrial complex of Tetrameringia sp., ventral view; (17) same, lateral view, plus ejaculatory apodeme. Figs (Lonsdale 2014, figs 66 68). Abbreviations: ann (st 6 8) annulus (sternites 6 8); basph basiphallus; cerc cerci (fused); distph distiphallus; ej apod ejaculatory apodeme; epand epandrium; epiph epiphallus; hypd hypandrium; pgt postgonite; phapod phallapodeme; pph paraphallus; pregt pregonite; sur surstylus. CLUSIIDAE (DRUID FLIES) 81

5 14 SURICATA X (20XX) Biology and immature stages Adult Clusiidae are infrequently encountered in the field, although north temperate species can sometimes be collected with regularity in Malaise and pan traps in favoured habitats, such as partial grasslands and predominantly deciduous woodland. Conversely, mossy, humid habitats, often near waterways appear to be favoured in tropical regions. Heteromeringia spp. are more frequently encountered in open areas, such as tree falls, landslides and pastures (Lonsdale & Marshall 2010; Lonsdale et al. 2011). Within these habitats, individuals are often found in sunspots on the upper or lower surfaces of foliage. Adults are also often encountered on dead wood, such as stumps, fallen logs or branches, frequently in association with mammal or bird dung, but observations suggest that this behaviour may be less frequent in the New World tropics (Lonsdale & Marshall 2010). Adults have also been found on rotting meat (Caloren & Marshall 1998; Sasakawa 1998) and are known to feed on fungal fruiting bodies (Caloren & Marshall 1998), nectar, rotting vegetable matter and sap (Soós 1987). Many north temperate species have been found to develop within rotting wood, often under bark, and while several species are known from a single host species or genus, this may be a collecting artifact, as most other clusiids have been reared from a variety of deciduous and coniferous species (Caloren & Marshall 1998; Roháček 1995; Rotheray & Horsfield 2013; Withers 1985). Selection of oviposition sites by females does not appear to be associated with any particular species of tree, but is linked to humidity, amount of shade, stage of wood decay, [and the] presence of mycelia of certain fungi (Roháček 1995: 124). While immatures appear to be more frequently recovered from wood in an advanced state of decay with soft whitewood (Rotheray & Horsfield 2013), some Clusiodes Coquillett have been found developing in freshly fallen trees (Caloren & Marshall 1998). Some Sobarocephala spp. have also been found in termite colonies (Sóos 1987). Within the decaying wood, clusiid larvae appear to feed on biofilms through spot sucking actions and are unlikely to be predacious, due to their reduced cephaloskeleton and slow movement (Rotheray & Horsfield 2013). The position of larvae in fallen logs appears to be towards the underside of the wood between the annual rings and broken whitewood, but puparia are found towards the upper surface close to cracked bark or exposed inner wood; stump-inhabiting species also appear to pupariate towards the upper surface (Rotheray & Horsfield 2013). Wood similar to, but less decayed than that selected for the larval habitat, is also used by species in all three subfamilies as a substrate for pre-copulatory and copulatory behaviour, although at least one species of Neotropical Sobarocephala uses the underside of broad leaves (Lonsdale & Marshall 2012). As part of pre-copulatory behaviour, clusiids are among the few acalyptrates known to establish leks, where the males defend territories within an arena devoid of resources from other lekking males, with females selecting males based on the quality of the territory held, leading to an asymmetry in reproductive success amongst males. True lekking, in this strict sense, has only been observed in the subfamily Clusiodinae (Caloren & Marshall 1998; Lonsdale & Marshall 2006b, 2007b; Marshall 2000), although territoriality and male agonistic behaviour has been observed in all subfamilies, and structural or colour modification associated with pre-copulatory display are present in all genera, particularly on the head, wings and fore legs (Lonsdale & Marshall 2010, 2012; Lonsdale et al. 2011, unpubl.; Marshall 2000). When males encounter each other in a lek, they appear to assess body size in an attempt to determine which male is largest, this male being the most likely to win in a violent confrontation. The larger male subsequently retains or gains control of the territory, avoiding unnecessary and costly physical confrontation. Violence usually occurs only when the males are of near equal size and it is uncertain which individual would win in a fight, although ambush attacks are also components of agonistic behaviour in some species (Caloren & Marshall 1998). It is assumed that leg and wing displays, widened heads, modified vibrissae, elongate antennae and other such visual components of pre-copulatory display exaggerate body size for more accurate measurement of fitness (Marshall 2000), although their utility in violent confrontation and male/ female interaction may also be significant. Immature stages are not known for Afrotropical species, but clusiid eggs described for genera that occur in the Afrotropics are approximately as long as female sternite 6, three or four times longer than wide, with a small, slightly raised terminal micropile, and are tapered at both ends (Lonsdale 2009; Lonsdale & Marshall 2012; Lonsdale et al. 2011). The surface is translucent, usually tuberculate, with longitudinal wrinkles or furrows (Fig. 39). Larvae have been described for species of European Clusiodes in Malloch, (1918) and Soós (1987); Rotheray & Horsfield (2013) have also recently provided a comprehensive analysis of the immature stages of several Palaearctic Clusia Haliday and Clusiodes spp. Described larvae are white and tapered at both ends, segmental boundaries are visible as raised, impressed or otherwise obvious lines; the prothorax is truncated with surrounding sensillae; the anterior spiracles are posterolateral on the prothorax, fan-shaped, with 3 10 respiratory papillae; the anal pad is pale and the posterior spiracles are elevated on sclerotised plates, which are produced as dorsally curving hooks; spiracular openings elongate-oval in radial pattern (Figs 43, 44). The mouthhooks are small and well sclerotised and the cephaloskeleton is unpigmented, exhibiting significant reduction and fusion (Fig. 45). The pseudocephalon lacks a facial mask with oral ridges, and the atrium is oblique (Rotheray & Horsfield 2013). Puparia (Figs 42 44) are known from several species in all three subfamilies (Sabrosky & Steyskal 1974; Lonsdale & Marshall 2007b; Lonsdale 2009; Lonsdale et al. 2011) and several Clusia and Clusiodes spp. were treated thoroughly in Rotheray & Horsfield (2013). Puparia are dark brownish orange, with the anal pad darker and more heavily sclerotised. There are numerous minute transverse wrinkles, although the posterior segment is smooth with various sculpturing (wrinkles and divots) and is either sharply curved and bordered by a high ridge (Clusia and Sobarocephala), or broadly rounded with the ridge broken and shallow (Clusiodes). The anal hooks bearing the posterior spiracles either curve dorsally (Clusiodes), or medially to dorsomedially and are ovate (Clusia, Heteromeringia), or semi-circular (Sobarocephala) in cross-section; the anal hooks of Heteromeringia species (known from Australian H. norrisi McAlpine, 1960 and Nearctic H. nitida Johnson, 1913 (Lonsdale, unpublished data)), have an additional pointed process medially. MANUAL OF AFROTROPIAL DIPTERA VOLUME 2

6 SURICATA X (20XX) 15 Figs Male terminalia of Clusiidae: (18) external components of Tetrameringia sp., lateral view; (19) same, posterior view; (20) hypandrial complex of Hendelia sp., ventral view; (21) same, lateral view; (22) same, ejaculatory apodeme. Abbreviations: ej apod ejaculatory apodeme; hypd hypandrium; pgt postgonite; ph phallus; phapod phallapodeme; sur surstylus. CLUSIIDAE (DRUID FLIES) 81

7 16 SURICATA X (20XX) Figs Male terminalia of Clusiidae: (23) external components of Hendelia sp., lateral view; (24) same, posterior view; (25) hypandrial complex of Czernyola sp., ventral view; (26) same, hypandrial complex, lateral view; (27) same, ejaculatory apodeme; (28) same, external components, lateral view; (29) same, external components, posterior view. Abbreviations: cerc cerci (fused); epand epandrium; phapod phallapodeme; hypd + pregt hypandrium + pregonite; st sternite; sur surstylus. MANUAL OF AFROTROPIAL DIPTERA VOLUME 2

8 SURICATA X (20XX) 17 Economic significance No species of economic significance are currently known. Classification The Clusiidae has been treated as a member of the superfamily Opomyzoidea (McAlpine 1989), or at least as a close relative of the Agromyzidae (Griffiths 1972). A recent molecular study (Winkler et al. 2010) has revealed the superfamily to be an artificial grouping of families, however, and there is little substantial morphological evidence to establish any sister-group relationships with the Clusiidae (Lonsdale et al. 2010). Within the Clusiidae, Frey (1960) first split the family into two subfamilies, with the Clusiinae defined by having one of the fronto-orbitals inclinate (Fig. 8), and the Clusiodinae defined by having all of the fronto-orbitals reclinate (Fig. 10). Steyskal (1965) later transferred Czernyola to the Clusiodinae (third posterior seta inclinate) (Fig. 9), leaving the subfamilies to be defined by having only the anterior fronto-orbital inclinate (Clusiinae) or reclinate (Clusiodinae). This system is still followed by Sasakawa (2011), although Lonsdale & Marshall (2006a) determined that neither of these subfamily concepts based on a single character of fronto-orbital chaetotaxy corresponded with clades based on other external morphological and terminalia characters. Based on a wider suite of characters, Lonsdale & Marshall (2006a) transferred Heteromeringia to the Clusiodinae, and divided the Clusiinae into the new subfamily Sobarocephalinae and a reduced Clusiinae. These results were corroborated by the molecular analyses of Lonsdale et al. (2010), with the exception that the Chilean genus Apiochaeta Czerny, 1903 was strongly supported as Sobarocephalinae. This resulted in a slightly refined classification that is more parsimonious biogeographically, with a mostly New World tropical Sobarocephalinae (some Sobarocephala are Nearctic or Old World tropical in distribution) and a mostly Old World tropical Clusiinae (although most Clusia are north temperate in distribution). The genera of Clusiidae are now grouped as follows, with those occurring in the Afrotropics marked with an asterisk: 1) Sobarocephalinae Apiochaeta, Chaetoclusia Coquillett, Procerosoma Lonsdale & Marshall and Sobarocephala*. 2) Clusiinae Clusia, Melanoclusia Lonsdale & Marshall, Phylloclusia Hendel and Tetrameringia*. 3) Clusiodinae Allometopon*, Clusiodes, Czernyola*, Hendelia*, Heteromeringia* and Electroclusiodes Hennig. The Sobarocephalinae consists of two small genera from the tropical Neotropics, the Chilean Apiochaeta and the largest genus of Clusiidae, Sobarocephala. Sobarocephala is mostly New World in distribution, but a number of species are found throughout the Old World tropics, mostly in the Oriental and Afrotropical Regions, but also in the eastern Palaearctic Region and parts of the Australasian Region as far south as northern Australia (Lonsdale, 2014). Like the Clusiinae, this subfamily has an inclinate anterior fronto-orbital seta, but there are several derived male terminalia features (Figs 13 15) and a dorsal preapical seta is present on the mid tibia (absent in Clusiinae). The tibial seta is only absent in Procerosoma, which is typified by an overall reduction in chaetotaxy, but its sister-group relationship to Sobarocephala is strongly supported (Lonsdale & Marshall 2006a). The Clusiinae are characterised by an absence of dorsal preapical setae on all tibiae, a slight posteromedial emargination on the frons and a small surstylus and paraphallus (Figs 16 19). There are also often minute black setulae on the frons, a relatively short distal section of vein M and a strong horizontal fascia on the pleuron. Of the four clusiine genera, only Tetrameringia (Fig. 1) occurs in the Afrotropics, with species also found in Japan and eastern Australia. Clusia is north temperate and Oriental in distribution, Melanoclusia is restricted to Borneo (Lonsdale & Marshall 2008a) and Phylloclusia (the sister genus to Tetrameringia), is found from Sri Lanka to Borneo, Taiwan and Japan (Lonsdale & Marshall 2007c). The Clusiodinae is a widespread and speciose subfamily with roots in the Oriental and Australasian Regions, and while most genera have entirely reclinate fronto-orbital setae, Czernyola has the third posterior seta inclinate (anterior 1 or 2 setae reclinate) (Fig. 9) and Heteromeringia (Fig. 8) has the anterior of its three fronto-orbitals inclinate. Excluding Allometopon, the subfamily is further supported by numerous male and female terminalia characters (e.g., Lonsdale et al. 2010), as well as external characters including a dorsally flattened and wrinkled scutellum and reduced extensions on the inner and outer margins of the pedicel. Czernyola, Clusiodes and Hendelia likely form a natural group as these are the only Clusiidae with dorsal preapical setae on both the mid and hind tibiae; the last two are further supported as sister taxa on the basis of numerous synapomorphies, including interfrontal setae and unique male terminalia (Lonsdale & Marshall 2007b). This subfamily is relatively well represented in the Afrotropics by the widespread genera Heteromeringia and Czernyola, which appear to be the most frequently encountered taxa, Hendelia (Fig. 10), and the predominantly Australasian Allometopon, which occurs in the Seychelles. Identification Due to a paucity of revisionary work on the Afrotropical Clusiidae, the fauna remains poorly-known, although a key to the genera of sub-saharan Africa was developed by Stuckenberg (1973), and Lonsdale (2014) revised and keyed the Old World Sobarocephala, including nine African species. More recently, Lonsdale et al. (2010) published a key to the World genera of Clusiidae and Lonsdale et al. (2011) developed electronic keys to genera, both in dichotomous and matrix-based formats. Descriptions of the Afrotropical fauna are found in Lamb (1914), Verbeke (1968), Stuckenberg (1973), Barraclough (2002) and Lonsdale (2014), including 16 species in four genera, although Barraclough (2002) is likely correct in estimating that there may be many more species to be discovered. The two species described by Verbeke (1968) were originally placed in Strongylophthalmyia Heller (not known from the Afrotropical Region), but these were recombined as Heteromeringia and Tetrameringia by Barraclough (2000). CLUSIIDAE (DRUID FLIES) 81

9 18 SURICATA X (20XX) Figs Male terminalia of Clusiidae: (30) hypandrial complex of Heteromeringia tephrinos Lonsdale & Marshall, ventral view; (31) same, hypandrial complex, lateral view; (32) same, ejaculatory apodeme, lateral view; (33) same, external components, lateral view; (34) same, posterior view. Abbreviation: hypd + pregt hypandrium + pregonite. MANUAL OF AFROTROPIAL DIPTERA VOLUME 2

10 SURICATA X (20XX) 19 Key to genera of Afrotropical Clusiidae 1. Frons with anterior fronto-orbital seta reclinate (Figs 9, 10); if mid tibia with dorsal preapical seta, then hind tibia always with similar seta...clusiodinae (excluding Heteromeringia) 2 Frons with anterior fronto-orbital seta inclinate (Fig. 8); if mid tibia with dorsal preapical seta, hind tibia never with similar seta Antenna with outer margin of pedicel with triangular extension long and sharply pointed (Fig. 12); head with posterior fronto-orbital seta as long, or longer than, other fronto-orbital setae; scutellum smooth and convex; preapical tibial seta absent; male terminalia with pregonite small and separate from hypandrium (as in Fig. 13); phallapodeme long, well-developed, with ventral shield; postgonite present; phallus rod-like, with basiphallus and distiphallus separate... Allometopon Kertész Antenna with outer margin of pedicel with triangular extension obtuse and blunt (Fig. 11); head with posterior fronto-orbital seta often shorter than remaining fronto-orbital setae, or absent, leaving 2 setae (Fig. 10); scutellum flat and longitudinally wrinkled; mid and hind tibiae with dorsal preapical setae; male terminalia with pregonite large and fused to hypandrium (Figs 26, 31); phallapodeme greatly reduced; postgonite absent; phallus sac-like or atrophied, with basiphallus and distiphallus fused (epiphallus fused to basiphallus, or lost) Interfrontal seta absent (Fig. 9); 4 or 5 pairs of fronto-orbital setae; third posterior seta inset and inclinate; genal setae small and setula-like, hind seta sometimes well-developed; male terminalia with surstylus with no setae on outer face (at least anteriorly), usually directed ventrally and twisted so that inner face visible posteriorly (Figs 28, 29); phallapodeme rod-like (Fig. 26); ejaculatory apodeme mushroom-shaped (Fig. 27); ventral receptacle without subapical disc (Fig. 38)...Czernyola Bezzi Interfrontal seta present (Fig. 10); 2 or 3 fronto-orbital setae, all reclinate, with anterior and posterior setae small to absent; several medial genal setae more strongly-developed; male terminalia with surstylus evenly setulose, usually small and medially-directed (Figs 23, 24); phallapodeme carinate (Fig. 21); ejaculatory apodeme long and thin (Fig. 22); ventral receptacle with subapical disc...hendelia Czerny 4. Lateral margin of pedicel with triangular extension lobtuse and blunt (Fig. 11); scutellum flat and longitudinally wrinkled; mid tibia without dorsal preapical seta; often with either white fore tarsomeres, or male with small pilose disc on anepisternum; distiphallus elongate, coiled, black and double-ribbed (Figs 30, 31); paraphallus absent; fused sternites 6 8 with enlarged ventral membranous pouch enclosing distiphallus when at rest; spermathecae strongly telescoped and dark; ventral receptacle with subterminal flagellum (Fig. 41) (CLUSIODINAE [in part])... Heteromeringia Czerny Lateral margin of pedicel with triangular extension long and sharply pointed (Fig. 12); scutellum slightly convex and smooth; mid tibia sometimes with dorsal preapical seta; fore tarsomeres never white and male never with small pilose anepisternal disc; paraphallus present; distiphallus composed of linear sclerite that is rod-like or with medial joint (Figs 13, 16); spermathecae not telescoped and usually clear; ventral receptacle without flagellum (Fig. 36) Head with 3 pairs of fronto-orbital setae; antennal arista with setulae dense at base; mid tibia with dorsal preapical seta; vein M 1+2 ratio (length of ultimate section of vein M 1 divided by penultimate) of wing greater than 3.0 (Fig. 2); cell bm open; male terminalia with surstylus broadly rounded, without inner-basal process, although rarely with pointed extension on posterobasal margin (Figs 14, 15); distiphallus unbroken, relatively straight, with basal shield-like sclerite (Fig. 13) (SOBAROCEPHALI- NAE) Sobarocephala Czerny Head with 4 pairs of fronto-orbital setae; antennal arista with setulae sparse along length; mid tibia never with dorsal preapical seta; vein M 1+2 ratio of wing less than 2.7 (Fig. 3); cell bm closed; male terminalia with surstylus usually small to minute, triangular and/or with acute inner-basal process (Figs 18, 19); distiphallus elongate and broken medially, without ventrobasal shield-like sclerite (i.e., exposed at base) (CLUSIINAE)...Tetrameringia McAlpine Synopsis of the fauna Allometopon Kertész. This infrequently encountered genus occurs in the Oriental Region, Japan and eastern Australia. Allometopon flavum Lamb 1914, the only Afrotropical species, is known from a single collection from the Seychelles (Lamb, 1914). While species may be confused with Sobarocephala, which often has similar pale colouration, the anterior fronto-orbital seta of Allometopon is reclinate, there are no dorsal preapical tibial setae and the surstylus is often larger and unusually shaped. All other clusiids with a reclinate anterior fronto-orbital (that is, the remainder of the subfamily excluding Heteromeringia), have well-developed dorsal preapical setae on both the mid and hind tibiae. Allometopon is smaller than most clusiids, often being less than 4.0 mm in length and usually with a reduced postvertical seta, a large, triangular and silvery CLUSIIDAE (DRUID FLIES) 81

11 20 SURICATA X (20XX) Figs Female abdomen, egg and spermathecae of Clusiidae: (35) female abdomen of Tetrameringia sp., ventral view; (36) same, internal terminalia; (37) female abdomen of Czernyola sp., ventral view; (38) same, internal terminalia; (39) female abdomen beyond segment 4 of Heteromeringia sp., ventral view (egg and detail of egg microsculpture above); (40) same, abdomen beyond segment 4, lateral view; (41) same, internal terminalia. Abbreviations: cerc cercus; flg v rep flagellum of ventral receptacle; spm dt sperm duct; spmth spermatheca; st sternite; tg tergite; v rep ventral receptacle. MANUAL OF AFROTROPIAL DIPTERA VOLUME 2

12 SURICATA X (20XX) 21 gena and postgena, and a posteriorly displaced and reduced anterior dorsocentral. There are 14 described species, but numerous undescribed species are known to occur throughout the Indo-Australian Region, and it is likely that undescribed species also occur in south Asia and the continental Afrotropics. Czernyola Bezzi. Czernyola often treated as Craspedochaeta Czerny, 1903 in the literature is a diverse genus mostly occurring in tropical regions, with several species extending into Nearctic and south temperate regions. There are 50 described species, but many unnamed taxa throughout the Old World tropics await revisionary treatment. The New World fauna is better known, with 31 described species (Lonsdale & Marshall 2006b). The genus is unknown in Africa, but a number of undescribed species have been examined, mostly from equatorial countries and it is expected to occur throughout much of sub-saharan Africa. Species of Czernyola are generally small and dark, although the legs are often paler and some species are mostly yellow with a brown thoracic pattern. Males of Old World species are often paler than females and many of these exhibit a pronounced sexual dimorphism that is also characteristic of many Old World Heteromeringia, making species identification problematic. Most defining characters of the genus are male genitalic (Figs 25 29), but all species can be readily diagnosed in having reclinate fronto-orbitals with the third posterior seta proclinate and inclinate (Fig. 9). Furthermore, most Old World species, including all specimens examined from the Afrotropics, have the posterior fronto-orbital reduced, the posterior genal seta vibrissa-like and the spermatheca coiled. Hendelia Czerny. Most species of this morphologically diverse genus occur in tropical regions, with a minority in eastern Australia, but several are east Palaearctic in distribution and the type species (H. beckeri Czerny, 1903) is widespread from Japan to Europe. The genus was redefined by Lonsdale & Marshall (2007b) and it now includes 53 named species, many of which were previously treated as Clusiodes, its mostly north temperate sister genus. While Hendelia is defined on the basis of male genitalic characters (Figs 20 24), it can be easily identified on the basis of diagnostic external characters. Like Clusiodes, Hendelia has one pair of interfrontal setae and three reclinate fronto-orbital setae, with the anterior and posterior setae strongly reduced to absent (both are never absent simultaneously) (Fig. 10). Unlike Clusiodes, however, Hendelia lacks a pubescent arista, white notal fascia, or equidistant fronto-orbital setae if all three pairs are present. Furthermore, the male surstyli are almost always very small and mediallydirected and the head and/or antenna may be enlarged (Lonsdale & Figs Immature stages of Clusiidae: (42) puparium of Clusiodes johnsoni Malloch, lateral view; (43) same, C. johnsoni, posterior face (non-afrotropical); (44) same, C. melanostomus (Loew), posterior face; (45) cephaloskeleton of third-instar larva of Clusia flava (Meigen), lateral view (non-afrotropical). Figs (Lonsdale & Marshall 2007b, figs 8 10); Fig. 45 (after Rotheray & Horsfield 2013, figs 60, 61). CLUSIIDAE (DRUID FLIES) 81

13 22 SURICATA X (20XX) Marshall 2007b). Several undescribed species from equatorial countries are the only Hendelia known from the Afrotropics, but the genus is expected to occur throughout the Region. Heteromeringia Czerny. As is the case with Czernyola and Hendelia, species of Heteromeringia are mostly tropical in distribution with several outliers in the north temperate regions, but a considerable number of species are also found in Australia, predominantly in the east (Lonsdale 2009). Eighty-six species have been described, but dozens of unnamed species occur throughout the Old World tropics in the Oriental, Afrotopical and Oceanic Regions (Lonsdale, unpublished). Only three species are presently described from the Afrotropics H. aethiopica (Verbeke, 1968) (D.R. Congo), H. nigriceps Lamb, 1914 (Seychelles), and H. tephrinos Lonsdale & Marshall, 2007a (Seychelles, South Africa; replacement name for H. nigrifrons Lamb, 1914). Heteromeringia, redefined by Lonsdale & Marshall (2008b), can be diagnosed by having an inclinate anterior fronto-orbital seta (similar to genera in the Clusiinae and Sobarocephalinae) (Figs 1, 8), a shallow angulate extension on the outer face of the pedicel (Fig. 11), no preapical tibial setae, minute to absent lateral scutellar setae and a long, coiled double-ribbed distiphallus (Figs 30, 31). Many Afrotropical species are also predominantly dark in colouration, with the legs and venter of the pleuron often being partly yellow, and many males and some females have a small pilose spot on the anepisternum ( anepisternal disc ). Heteromeringia species are often associated with relatively open areas such as tree falls and pastures and many species have been collected using dung, mushrooms or carrion (Lonsdale & Marshall 2010). Sobarocephala Czerny. Sobarocephala is a large genus with 240 described species in the New World, most of which are found in tropical Central and South America. The Old World fauna was treated in Lonsdale (2014), (re)describing 29 species throughout the Oriental and Afrotropical Regions, as well as in parts of Oceania, northern Australia and the eastern Palaearctic. There are nine described Afrotropical species, including S. plumicornis (Lamb, 1914) (Seychelles), S. milangensis Stuckenberg, 1973 (southeast Africa) and S. zuluensis Stuckenberg, 1973 (South Africa) (Figs 13 15), and six species described by Lonsdale (2014): S. doryphoros (Madagascar, Seychelles), S. insolata (Madagascar), S. laticrinis (Tanzania), S. magna (Nigeria), S. myllolabis (Burundi) and S. recava (Madagascar). Sobarocephala can be differentiated from other Old World Clusiidae by having the anterior fronto-orbital seta inclinate, no interfrontal seta, a dorsal preapical tibial seta only on the mid leg, and an open cell bm (Fig. 2). Species are mostly yellow, with variable brown patterning on the dorsum of the thorax and abdomen and many species have a short plumose arista with the hairs more densely clustered basally. North temperate Sobarocephala are often found on fallen tree trunks, particularly those baited with dung, but tropical species (to date observed only in the New World), are also found around damp, mossy areas near water, usually on the underside of leaves (Lonsdale & Marshall 2010). Tetrameringia McAlpine. This is a relatively small genus with seven described species, but additional undescribed species are known from the Afrotropics. There is one described Tetrameringia from Japan, one from Laos, two from Australia and three from the Afrotropical Region, namely: T. aethiopica Stuckenberg, 1973 (South Africa), T. distoma (Verbeke, 1963) (Madagascar), and T. stuckenbergi Barraclough, 2002 (Malawi). The genus is defined by four fronto-orbital setae, the anterior of which is inclinate (although the posterior seta is sometimes reduced to absent in the Australian T. ustulata McAlpine, 1960). Male (Figs 16 19) and female (Figs 35, 36) terminalia strongly support Tetrameringia as the sister-group to Phylloclusia, known from Southeast Asia and Sri Lanka (Lonsdale & Marshall 2007c). Australian Tetrameringia have been collected over a dry stream bed in dry forest (Lonsdale & Marshall 2007c). Literature cited Barraclough, D.A The identity of Strongylophthalmyia Heller species (Diptera: Schizophora: Strongylophthalmyiidae) described from the Afrotropical Region, and their transfer to the family Clusiidae. Annals of the Natal Museum 41: Barraclough, D.A A new species of Tetrameringia McAlpine (Diptera: Schizophora: Clusiidae) from Malawi, the third species from the Afrotropical Region. African Invertebrates 43: Caloren, D.C. & Marshall, S.A A revision of the New World species of Clusiodes Coquillett (Diptera: Clusiidae). Studia dipterologica 5: Frey, R Studien über indoaustralische Clusiiden (Dipt.) nebst Katalog der Clusiiden. Commentationes Biologicae 22: Griffiths, G.C.D The phylogenetic classification of Diptera Cyclorrhapha with reference to the structure of the male postabdomen. The Hague: Dr. W. Junk N.V. Publishers. Lamb, C.G Diptera: Heteroneuridae, Ortalidae, Trypetidae, Sepsidae, Micropezidae, Drosophilidae, Geomyzidae, Milichidae. Transactions of the Linnean Society of London (2 nd Series, Zool.) 16: Lonsdale, O The Heteromeringia (Diptera: Clusiidae: Clusiodinae) of Australia. Records of the Australian Museum 61: Lonsdale, O Revision of the Old World Sobarocephala (Diptera: Clusiidae). Zootaxa 3760: Lonsdale, O. & Marshall, S.A. 2006a. Redefinition of the Clusiinae and Clusiodinae, description of the new subfamily Sobarocephalinae, revision of the genus Chaetoclusia and a description of Procerosoma gen. n. (Diptera: Clusiidae). European Journal of Entomology 103: Lonsdale, O. & Marshall, S.A. 2006b. Revision of the New World Craspedochaeta Czerny. Zootaxa 1291: Lonsdale, O. & Marshall, S.A. 2007a. Revision of the New World Heteromeringia (Diptera: Clusiidae: Clusiodinae). Beiträge zur Entomologie 57: Lonsdale, O. & Marshall, S.A. 2007b. Redefinition of the genera Clusiodes and Hendelia (Diptera: Clusiidae, Clusiodinae), with a review of Clusiodes. Studia dipterologica 14: Lonsdale, O. & Marshall, S.A. 2007c. Revision of the genus Phylloclusia (Diptera: Clusiidae: Clusiinae). The Canadian Entomologist 138: MANUAL OF AFROTROPIAL DIPTERA VOLUME 2

14 SURICATA X (20XX) 23 Lonsdale, O. & Marshall, S.A. 2008a. Synonymy within Clusia and description of the new genus Melanoclusia. Annals of the Entomological Society of America 101: Lonsdale, O. & Marshall, S.A. 2008b. The Clusiidae (Diptera: Schizophora) of Fiji, with redefinition of Heteromeringia Czerny and synonymy of Tranomeringia Sasakawa. In: Evenhuis, N.L. & Bickel, D.J., eds, Fiji Arthropods XI. Bishop Museum Occasional Papers 98: Lonsdale, O. & Marshall, S.A : Clusiidae (clusiid flies). In: Brown, B., Borkent, A., Cumming, J.M., Wood, D.M., Woodley, N.E. & Zumbado, M.A., eds, Manual of Central American Diptera, Volume 2. Ottawa: NRC Research Press, pp Lonsdale, O. & Marshall, S.A Sobarocephala (Diptera: Clusiidae: Sobarocesphalinae) subgeneric classification and revision of the New World species. Zootaxa 3370: Lonsdale, O., Cheung, D.K.B. & Marshall, S.A Key to the world genera and North American species of Clusiidae (Diptera: Schizophora). Canadian Journal of Arthropod Identification No. 14. Available at: doi: / cjai (accessed 10 August 2013). Lonsdale, O., Marshall, S.A., Fu, J. & Wiegmann, B Phylogenetic analysis of the druid flies (Diptera: Schizophora: Clusiidae) based on morphological and molecular data. Insect Systematics and Evolution 41: Malloch J.R A revision of the dipterous family Clusiodidae (Heteroneuridae). Proceedings of the Entomological Society of Washington 20: 2 8. Marshall, S.A Agonistic behaviour and generic synonymy in Australian Clusiidae (Diptera). Studia dipterologica 7: 3 9. McAlpine, D.K A review of the Australian species of Clusiidae (Diptera: Acalyptrata). Records of the Australian Museum 25: McAlpine, J.F Phylogeny and classification of the Muscomorpha. In: McAlpine J.F. & Wood, D.M., eds, Manual of the Nearctic Diptera, Volume 3. Ottawa: Research Branch, Agriculture Canada. Monograph No. 32, pp Roháček, J Clusiidae (Diptera) of the Czech and Slovak Republics: faunistics and notes on biology and behaviour. Časopis Slezského zemského Muzea (A) 44: Rotheray, G.E. & Horsfield, D Development sites and early stages of eleven species of Clusiidae (Diptera) occurring in Europe. Zootaxa 3619: Sabrosky, C.W. & Steyskal, G.C The genus Sobarocephala (Diptera: Clusiidae) in America North of Mexico. Annals of the Entomological Society of America 67: Sasakawa, M Family Clusiidae. In: Papp, L. & Darvas, B., eds, Contributions to a manual of Palaearctic Diptera (with special reference to flies of economic importance) Volume 3: Higher Brachycera. Budapest: Science Herald, pp Sasakawa, M Oriental species of clusiid flies (Diptera: Clusiidae: Clusiinae). Zootaxa 3038: Soós, Á Clusiidae. In: McAlpine, J.F., Peterson, B.V., Shewell, G.E., Teskey, H.J., Vockeroth, J.R. & Wood, D.M., coordinators, Manual of Nearctic Diptera. Volume 2. Ottawa: Research Branch, Agriculture Canada, Monograph No. 28, pp Steyskal, G.C Family Clusiidae. In: Stone, A., Sabrosky, C.W., Wirth, W.W., Foote, R.H. & Coulson, J.R., eds, A Catalog of the Diptera of America North of Mexico. Washington, D.C.: United States Department of Agriculture, Agricultural Research Service, pp Stuckenberg, B.R New and little-known Clusiidae (Diptera) from South Africa and Moçambique. Annals of the Natal Museum 21: Verbeke, J Note sur quelques Psilidae et Micropezidae éthiopiens et malgaches (Diptera, Acalyptera). Revue de Zoologie et de botanique africaines 67: Verbeke, J Psilidae (Diptera Acalyptera). Exploration du parc national de la Garamba Mission H. de Saeger 53: Brussels: Institut de Parcs Nationaux du Congo et du Ruanda-Urundi. Winkler, I.S., Rung, A. & Scheffer, S.J Hennig s orphans revisited: testing morphological hypotheses in the Opomyzoidea (Diptera: Schizophora). Molecular Phylogenetics and Evolution 54: Withers, P Notes on some British Clusiidae and reduction of Clusiodes facialis (Coll.) to synonymy. Proceedings and Transactions of the British Entomological and Natural History Society 18: CLUSIIDAE (DRUID FLIES) 81