A new genus and species of tachinid flies from Iran (Diptera, Tachinidae, Goniini)

Susamyia Ziegler & Gilasian gen. nov. and its type species Susamyia mira Ziegler & Gilasian gen. et sp. nov. are described from southwestern Karkheh National Park and southeastern Jazmourian Wetland of Iran. Drawings of terminalia and head of the male as well as images of habitus, head and egg are provided. Susamyia gen. nov. is incorporated into the identification key to the Palearctic tachinid genera of Tschorsnig & Richter (1998). The systematic position of Susamyia gen. nov. in the tribe Goniini (Exoristinae) is discussed in light of molecular analyses based on the ribosomal genes 16S, 18S and 28S, and the egg type of females. The morphology of the microtype eggs was studied and compared with that of other Goniini, but proved too unreliable to be included in the phylogenetic analysis. Susamyia gen. nov. is believed to be most closely related to the goniine genera Gymnophryxe Villeneuve, 1922, Palesisa Villeneuve, 1929 and Prosopodopsis Townsend, 1926.


Introduction
Tachinidae are an ecologically important family of parasitoid insects whose Iranian fauna is believed to comprise many surprising records or undescribed species. For example, our current studies just in the Karkheh and Dez National Parks, located in the southwestern province of Khuzestan, have resulted in the discovery of a number of taxa of which three species have already been found to be new to science (Gilasian et al. 2016a(Gilasian et al. , 2016b(Gilasian et al. , 2018(Gilasian et al. , 2019. This research was conducted as part of our ongoing study of the tachinid fauna of Persian Gulf provinces of Iran, including the southeastern Balouchestan region, and intended to improve the existing taxonomic knowledge of Tachinidae in Iran and in the Western Palearctic region. Our fi ndings show that this area is home to many interesting tachinid species, which have strong affi nities with other zoogeographical regions. The new species, discovered fi rst in the Karkheh National Park, was found to belong to an undescribed genus as its characters did not correspond with any other tachinid genera. Our preliminary morphological analysis showed that this species would be a member of the largest tachinid subfamily Exoristinae with estimated 3600 species worldwide, which also dominates the other tachinid subfamilies in the Palearctic region, with about 870 recorded species (O'Hara et al. 2020). Compared to the other subfamilies, Exoristinae shows the lowest level of morphological diversity representing good congruence with the results derived from DNA analysis indicating this subfamily as a young and rapidly evolving group of Tachinidae with the eryciine / goniine assemblage at the top (Stireman et al. 2019). Our new genus and species share the characters of the exoristine tribes Goniini and Eryciini, which are morphologically very close to each other; however, the species of Goniini are strikingly diff erent from Eryciini in their oviposition strategy of depositing specialized microtype eggs (Herting 1957). At the outset of this research, the lack of female specimens urged us to employ molecular analyses to reliably determine the position of the new genus. Although the new genus morphologically shares external characters that occur in both tribes Goniini and Eryciini, the results from molecular analyses and later the discovery of the female and its possession of microtype eggs confi rm the position of the new genus within Goniini.

Material and methods
The specimens of the new genus were collected in Karkheh and Dez National Parks with the exception of one female, which belongs to the southeastern Iranian side of the Balouchestan region (Figs 1-2). The Karkheh and Dez National Parks are situated in the southwestern province of Khuzestan, which is part of the Irano-Turanian biogeographic zone. The Khuzestan Plain, which borders Iraq on the west and Persian Gulf on the south, is known for its permanent large rivers whose sediments have created one of the most fertile agricultural lands in Iran. The climate is characterized by an annual precipitation of about 200-300 mm (winter rains), and long, hot and dry summers including high atmospheric humidity. The natural vegetation consists mainly of ephemeral forb communities (Gilasian et al. 2016a(Gilasian et al. , 2018. In addition to the type series of Susamyia mira Ziegler & Gilasian gen. et sp. nov., further pinned specimens of goniine and eryciine species from diff erent localities of the Palearctic region have been examined in the course of this study. The material is deposited in the following collections (abbreviations mostly from Evenhuis 2020):  All specimens of the new genus were captured directly in 75% ethanol containers of the Malaise traps (see Gilasian et al. 2016a: fi g. 2). To prepare some specimens from ethanol, we followed the AXA method proposed by van Achterberg (2009) to avoid shrinkage of the specimens before pinning (a single female specimen was glued). An Olympus SZH stereo microscope, equipped with a drawing tube, was used for preparing the drawings of head and male terminalia. Inked drawings were edited using Adobe Photoshop CS2. The preparation of the male terminalia was carried out according to the methods outlined in Gilasian et al. (2016b).
Digital images of the fl ies were taken by JZ through a Multifocus-Station Leica consisting of a Z16Apo stereo microscope and a DFC 495 digital camera operated by Leica Application Suite 4.5; Helicon Focus 6 was used for stacking the serial images. To extract the eggs, we detached the female abdomen and left it overnight in potassium hydroxide 10% at room temperature. Afterward, the mass of microtype eggs was removed from the abdomen and transferred into glycerin. The digital images of eggs were taken by JZ using a microscope Axioplan 2 with AxioCam MRc5 being equipped with the objectives Neofl uar 40 × 0.75 and Plan-Apochromat 63 × 1.40.
Measurements and ratios were calculated as proposed by Tschorsnig & Herting (1994) and Tschorsnig & Richter (1998). Statements given in square brackets in the description refer to paratypes. Overall lengths of specimens (in mm) were measured in lateral view from the anterior margin of the head, excluding the antenna, to the tip of the abdomen. The label data of specimens are given verbatim, with a forward slash separating diff erent lines, a double forward slash separating diff erent labels and descriptive information included in square brackets. The morphological terminology used in this paper follows Merz & Haenni (2000) (most external morphology), Stuckenberg (1999) Sinclair (2000) (male terminalia) and Tschorsnig & Richter (1998) (wing).

DNA extraction, PCR and sequencing
DNA was extracted from the ethanol-preserved adult fl ies using the DNeasy Blood & Tissue Kit (QIAGEN) following the manufacturer's protocol. Individual fl ies or tissue portions were rinsed in PBS, placed in sterile Eppendorf tubes and, after adding proteinase K, samples were incubated overnight at 56°C. PCRs (total volume = 20 μl) were performed using primers published in Roháček et al. (2009) (ribosomal 16S). Two nuclear genes, ribosomal 18S and 28S, were amplifi ed using primers according to Katana et al. (2001) and Belshaw et al. (2001), respectively. Amplifi ed products were purifi ed using the QIAquick PCR Purifi cation Kit (QIAGEN). Sequencing in both directions was carried out with BigDye Terminator ver. 3.1 (Applied Biosystems) on an ABI 3100 genetic sequencer (Perkin Elmer Applied Biosystems). All sequences were assembled and edited in SEQUENCHER ver. 4.8 (Gene Codes Corporation). GenBank accession numbers for the sequences are listed in Table 1.

Alignment and phylogenetic analyses
For the phylogenetic reconstructions and the most precise positioning of new genus Susamyia Ziegler & Gilasian gen. nov., we used the data available in GenBank based on the previous study of Tachi & Shima (2010). The data of the new genus were obtained during this study. The sequences were aligned using MAFFT ver. 7 (Katoh & Standley 2013) on the MAFFT server (http://maff t.cbrc.jp/alignment/server/). The fi nal dataset consisted of 28 specimens as terminal ʻtaxaʼ and 3486 DNA characters: 16S -407 bp, 18S -1798 and 28S -1281 bp.
To evaluate the best-fi t model for the Bayesian inference (BI) and maximum likelihood (ML) analyses, the concatenated data set was partitioned into three sets, representing the three gene regions (16S, 18S and 28S). Each DNA partition was evaluated in MrModeltest ver. 2.2 (Nylander 2004) using both hierarchical likelihood ratio tests (hLRTs) and Akaike information criterion (AIC). The model GTR + I + G was chosen as the best-fi tting model for all the partitions.
The partitioned Bayesian inference of 15 million generations on the concatenated data set was implemented in MrBayes ver. 3.2.6 (Huelsenbeck & Ronquist 2001) and carried out on the CIPRES (CyberInfrastructure for Phylogenetic RESearch) computer cluster, San Diego Supercomputing Center (Miller et al. 2010) with nucmodel = 4by4, ngen = 15mil, samplefreq = 1000, nruns = 2, and nchains = 4. Burn-in was set to 30%. All parameters were unlinked across partitions. The convergence of the runs was assessed by checking the potential scale reduction factor (PSRF) values of each parameter (in all cases, 1.000) and the standard deviation of split frequencies (< 0.002) in MrBayes. The ML analysis was conducted in Garli ver. 2.0 with the above mentioned substitution model GTR + I + G (Zwickl 2006).
Two independent runs of 5 million generations using the default automated stopping criterion were carried out. Nodal support was assessed using a nonparametric bootstrap with 500 replicates. Trees were rooted by the outgroup taxon Dinera takanoi (Mesnil, 1957), and the resulting tree was edited using iTOL (Letunić & Bork 2016). The node support values are given with the posterior probability (PP) and / or the bootstrap value (BV) appearing below nodes in the relevant trees ( Fig. 9).

Etymology
The fi rst part of the genus name 'Susamyia' (Latin, substantive feminine) refers to the historical name of the city of Susa, pronounced 'Shoush' in modern Persian, and permanently inhabited for 6200 years. The city is located in the southwestern Khuzestan Province of Iran, between the Karkheh and Dez Rivers, where the holotype was collected. The second part of the name is the Greek word ʻmyiaʼ, which means 'fl y'.

Description
Eye bare; gena with black setulae; height of gena in lateral view about 0.2 times as long as vertical diameter of eye; face 1.2-1.3 times as long as frons; frons at its narrowest point wider than an eye, at most 1.3 times as wide as an eye viewed dorsally; upper part of head without black setulae behind the postocular row; facial ridge with erect setae; parafacial bare, moderately narrow; fronto-orbital plate with 2 proclinate orbital setae and usually a single reclinate upper orbital seta, if two present, then uppermost stronger; postpedicel not pointed dorsoapically, much longer than pedicel; arista almost bare, thickened in basal ⅗; fi rst and second aristomeres short; prosternum setose; proepisternum bare; 3 strong basal setae of postpronotum arranged in a nearly straight line; scutum with 4 postsutural dorsocentral setae; fi rst postsutural supra-alar seta longer than notopleural setae; mesopleuron with black setulae; postmetacoxal area membranous; scutellum with 4 pairs of marginal setae; apical setae of scutellum at most inclined at 30° to horizontal; lateral scutellar setae strong and as long as basal setae; katepisternum with 3 setae almost in a line; lower calypter not exceptionally convex at outer margin; vein R 4+5 setose at most halfway to crossvein r-m; wing cell r 4+5 open or closed at wing margin; section of vein M between crossveins r-m and dm-cu distinctly longer than section between dm-cu and bend of M; bend of M forming a right angle; vein M complete; bend of vein M fl at, without continuation; crossvein dm-cu not exceptionally oblique; preapical anterodorsal seta on fore tibia shorter than preapical dorsal seta; mid tibia with a nearly complete row of diff erent-sized anterodorsal setae; hind coxa bare posterodorsally; hind tibia with 2 preapical dorsal setae; preapical posteroventral seta on hind tibia shorter than preapical anteroventral seta; abdomen predominantly covered with dense grey microtrichosity; middorsal depression of syntergite 1+2 extending back to posterior margin of that segment; tergites 3-4 without median discal setae. . Head predominantly brown; genal setulae black; frontal vitta and lunule light brown; face, parafacial, fronto-orbital plate, gena, genal dilation, ocellar triangle and occiput covered with dense silvery white microtrichosity; occiput with white setulae; scape, pedicel and basal margin of postpedicel orange, other parts of antenna including arista dark brown to black; prementum dark brown; palpus yellow; thorax black, predominantly covered with whitish-grey microtrichosity; presutural portion of scutum with 2 narrow dark median and 2 semi-triangular lateral vittae (seen from behind), posterior margin of postpronotum orange, postsutural portion of scutum orange laterally; scutellum entirely yellowish-orange or (rarely) darker in basal portion, covered with grey microtrichosity; wing hyaline; calypters white; tegula brownish-orange, basicosta pale yellow; halter orange; coxae, femora and tarsi brownish-black, apical half of femora orange ventrally, tibiae dark brownish-orange; abdomen dorsally and ventrally predominantly covered with dense grey microtrichosity on its whole length, without black bands posteriorly, but with black shining spots at base of every seta; syntergite 1+2 mostly black, posterior half of lateral and ventral portions orange; tergites 3-4 predominantly orange, each with a dorsal black trapezoidal spot; tergite 5 orange with a semi triangular black spot dorsally; margins of all tergites pale yellow; sternites black; postabdomen mostly orange. wide; arista thickened in basal ⅗, fi rst aristomere shorter than wide; second aristomere [2.0]-2.5 times as long as fi rst aristomere, 1.2-1.8 times as long as wide; prementum very short; palpus slender and cylindrical, with only a few setulae.
W . Second costal section bare ventrally; costal seta nearly as long as crossvein r-m; fourth costal section (between R 2+3 and R 4+5 ) approximately as long as second costal section (between subcostal break and R 1 ); third costal section 1. A . Middorsal depression of syntergite 1+2 extending back to posterior margin of segment; syntergite 1+2 and tergite 3 each with 1 pair of median marginal and 1 pair of lateral marginal setae; tergites 3-4 with depressed setulae dorsally, without median discal setae; tergite 3 0.45 times as long as wide; tergites 4-5 each with a complete row of marginal setae, tergite 5 with erect discal setae dorsally and 0.65 times as long as tergite 4. P (Fig. 4). Sternite 5 with a deep median apical depression, without sensilla trichodea (Fig. 4C); membrane binding between sternite 6 and segment 7 very narrow; epandrium 2.3 times as long as syntergite 6-8; cercus convex in the middle of basal part and depressed downwards in the middle of apical part (Fig. 4A); cercus and surstylus narrow in lateral view, surstylus longer than cercus (Fig. 4B); aedeagus as in fi g. 4D.

Key (based on Tschorsnig & Richter 1998)
The new genus Susamyia gen. nov. can be incorporated into the modifi ed identifi cation key of the Palearctic tachinid genera prepared by Tschorsnig & Richter (1998). One problem for the users of this key can be in distinguishing between upper frontal setae and upper orbital setae for which Tschorsnig & Richter (1998) also mentioned, through the morphological description of the adult head, "One, two or more reclinate or lateroclinate upper orbital bristles present, in many genera not distinguishable from uppermost frontal bristles …". The second problem is the intraspecifi c variation in the number of reclinate upper orbital bristles, which exist in Susamyia gen. nov. (cf. Figs 3, 6A, 8A with two vs Fig. 6C-E with only one) and other genera, including Palesisa Villeneuve, 1929, which usually possesses only one upper orbital seta (but in Fig. 8B with two). In case of two reclinate upper orbital setae, the anterior seta is mostly shorter than the second seta. In the description of Palesisa nudioculata, Cerretti (2010a: 276) stated "Una (raramente 2) setola orbitale reclinate superiore" and provided a photograph of the female head with two strong reclinate upper orbital setae (Cerretti 2010b: 124). Čepelák & Sisojević (1974: 834) had described the male of the same species as having "1 (auch 2, vordere kürzere) oi" [one or two reclinate upper orbital setae, the anterior seta shorter]. Mesnil (1949: 101) had used this character (one or two upper orbital setae) in his key to separate Sturmiariae from Blepharellariae, and mentioned that he had encountered specimens with both 2 oi (reclinate upper orbital setae) and 1 oi among the individuals of Pales pumicata (Meigen, 1824) (as Ctenophorocera). Even though the presence of 2-3 reclinate upper orbital setae has been described for the genus Gymnophryxe Villeneuve, 1922, mostly one is observed in G. theodori (Fig. 6F-H). These remarks are intended to discuss the reliability of the used characters "One single reclinate upper orbital seta" and "Two or more reclinate upper orbital setae" in the keys. Therefore, we off er here two variants of the key by Tschorsnig & Richter (1998) to facilitate the determination of Susamyia gen. nov. in both occurrences and include the following combinations "One single reclinate upper orbital seta, if sometimes two, the uppermost stronger" and "Two reclinate upper orbital setae, the uppermost of same size or weaker, or more than two setae" in place of the original ones in the key to improve its accuracy as well. Usually one reclinate upper orbital seta is present in G. theodori (Figs 6F-H)]. Apical scutellar setae inclined at 45-90° to horizontal (see Tschorsnig & Richter 1998: fi gs 126-127). Gena 0.3-0.5 times as height as vertical diameter of eye (Fig. 6F). Male terminalia: Surstylus in lateral view broader and shorter than cercus (Fig. 5D) (Fig. 6C). Frons at most 1.15-1.40 times as wide as one eye in dorsal view (Fig. 6E). Fronto-orbital plate in male with two strong proclinate setae (Fig. 6C-E) and one single reclinate upper orbital seta (sometimes a fi ne semi reclinate seta before, Fig. 3). Apical scutellar setae inclined at most at 30° to horizontal. Gena almost 0.2 times as heigh as vertical diameter of eye (Fig. 6C). Male terminalia: Surstyli and cerci in lateral view slender; surstylus longer than cercus (Fig. 5B)

Discussion
Within the subfamily Exoristinae, the tribes Goniini and Eryciini are considered morphologically and biologically close to each other and can be separated from the rest by the following characters: fi rst postsutural supra-alar seta longer than notopleural setae; cerci not fused as syncercus; katepimeron bare or at most with 3 setulae; postpedicel not pointed apically; outer margin of lower calypter weakly convex; distiphallus not reduced; ejaculatory apodeme developed (Tschorsnig & Herting 1994); ovolarviparous in Eryciini; micro-ovolarviparous in Goniini (Herting 1957). The species of Goniini lay their tiny eggs on the leaves of plants which are later swallowed by their hosts. The eggs hatch in the midgut of their host and the fi rst instar larvae rapidly move to the body cavity to complete their development (Stireman et al. 2019). Aside from their typical microtype eggs, the male Goniini also often diff er from the Eryciini in having a narrow membrane binding between sternite 6 and segment 7 and in absence of sensilla trichodea on sternite 5 (Tschorsnig 1985). The results of the molecular analyses (Fig. 9) and the microtype eggs, as well as lacking sensilla trichodea on sternite 5 and presence of a narrow membrane binding between sternite 6 and segment 7 in Susamyia gen. nov. position it reliably within Goniini.
We fi rst used the barcode COI fragment and as in Cerretti et al. (2015) we included a large number of species of both the tribes Eryciini and Goniini. We focused mainly on Palearctic species; however, the results were similar to those of Cerretti et al. (2015): neither the tribe Eryciini nor the Goniini were monophyletic; the examined taxa were clustered irregularly without any pattern supported by morphological characters. So, the new genus Susamyia gen. nov. was not positioned reliably in the tree as the apparent phylogenetic relationships were misleading. Earlier, Tachi & Shima (2010) used four gene markers to reconstruct the relationships of these two tribes, which resulted in a paraphyletic Eryciini and monophyletic Goniini. This fi nding was also supported by Stireman et al. (2019) based on 28S, CAD, MAC and MCS. We created a dataset based on four markers (16S, COI, 18S and 28S) in hope of more reliable placing of the new genus. After performing numerous analyses on several setups of the dataset, we decided to exclude the COI fragment which caused unnecessary interference and did not increase our ability to resolve phylogenetic issues in these evolutionarily young fl ies. Susamyia mira gen. et sp. nov. clustered very consistently in the tribe Goniini across all the analyses. In all obtained outputs, S. mira gen. et sp. nov. appeared as sister to Blepharipa sugens (Wiedemann, 1830), with this clade as sister to Frontina laeta (Meigen, 1824) (Fig. 9). Another outcome similar to above mentioned studies was the monophyletic Goniini which however also included the oviparous Aplomya confi nis (Fallén, 1820), the positioning of which is rather diffi cult to interpret. The largest molecular analysis of Tachinidae (Stireman et al. 2019) has Aplomya in a very special position as sister to the clade Eryciini + Goniini. Unfortunately, molecular data for other taxonomically close (but very rare) genera Gymnophryxe Villeneuve, 1922, Palesisa Villeneuve, 1929and Prosopodopsis Townsend, 1926 are not available in GenBank, and we had no access to fresh material for DNA extraction. Cerretti et al. (2014) used 135 morphological characters from species of all subfamilies and major tribes for cladistic analyses of Tachinidae. The Goniini branched out as a monophyletic lineage based on the special character of their ʻmicrotypeʼ eggs. We created a morphological matrix of adult Goniini for a cladistic analysis in which we also included Susamyia gen. nov. Unfortunately, the results were not statistically signifi cant because of the limited number of available data (trees yielded into several polytomies, data not shown). Nevertheless, Susamyia gen. nov. always formed a group together with Palesisa. The same branch also contained Blepharipa Rondani, 1856, Frontina and Pales Robineau-Desvoidy, 1830 and thus approached our DNA results (Fig. 9). Cerretti et al. (2014) did not include genera Blepharipa, Gymnophryxe and Prosopodopsis in the dataset for the cladistic analysis, but genera Palesisa, Dolichocolon, Prosopea Rondani, 1861 and Pales were present and branched out together, defi ned by character state 71(3) "Bend of wing vein M forming a right angle or, rarely, an acute angle". This is a homoplasious apomorphy, very often evolved in parallel and found in hundreds of Palearctic genera, and therefore not that helpful for phylogenetic interpretation.
In addition to the molecular data and the external morphology of adults, we also studied the eggs hoping to fi nd out characters of phylogenetic signifi cance. The data are mainly derived from the previous works of Thompson (1924), Herting (1960), Gaponov (1996) and Tachi (2013). Based on the literature, only the species Pexopsis capitata (see Borisova 1961) and Pexopsis pilosa (see Shima & Ichiki 2000) evolved unique eggs which are divided into two diff erent parts, either with deeply dark sclerotization or pale semi-transparent and soft. In all other Goniini, the eggs are planoconvex with the dorsal chorion varying from thin and semi-transparent or pale to thick and strongly sclerotized, brown or black, like in Susamyia mira gen. et sp. nov. But the diff erent levels of sclerotization seem to be of low phylogenetic value. As Tachi (2013) also argued, it is more likely that there was a correlation between the diff erent levels of sclerotization and pigmentation of the chorion as well as the degree of resistance of the eggs to dehydration and other unfavorable environmental conditions.
The eggs of several species were examined using scanning electron microscopes by Salkeld (1980), Marini & Campadelli (1994), and Gaponov (1996) who pointed out that the patterns on the dorsal chorions varied in shape and size in relation to each taxon. Gaponov (1996Gaponov ( , 2003aGaponov ( , 2003b and Tachi (2013) recognized two structural types within the Goniini of which the fi rst type had dorsally reticulated chorion, while the second type was defi ned by its punctiform openings of chorion. The dorsal chorion of Susamyia gen. nov. has a system of clearly punctiform openings on the surface, but the chorion is also (weakly) reticulated, showing a combination of characters of both groups, which also appears in other species including Allophorocera arator (Aldrich, 1925) and Eumea caesar (Aldrich, 1916) (Salkeld 1980). These character states, which cannot be clearly defi ned, tend to be homoplastic and their value through a phylogenetic analysis proved to be ineff ective.
It is important to note that the southern and southeastern regions of Iran, where the type series of Susamyia mira gen. et sp. nov. was collected, are known to serve as biogeographic crossroads for the Palearctic, Oriental and Afrotropical taxa (Abivardi 2001;Gilasian et al. 2018). For this reason, apart from the Palearctic genera, it was necessary to examine the non-Iranian genera in order to reliably establish the validity of Susamyia gen. nov. In contrast to the natural dispersal, many plant and animal species from the Nearctic have been accidentally introduced into other (climatically similar) parts of the world. To reliably confi rm the status of the Susamyia gen. nov. as a new genus, we also studied the North American Tachinidae (Wood 1987). For example, two alien Nearctic species are known to be introduced in Europe: Trichopoda sp. (see also Ziegler & Standfuss 2020), which is very diff erent from Susamyia gen. nov., and Lespesia frenchii (Williston, 1889) (Herting 1960). Based on the revision of the genus Lespesia by Beneway (1963), we have concluded that its species are not very similar with Susamyia gen. nov. and moreover, they are member of the tribe Eryciini. A superfi cially similar genus from North America is Frontiniella Townsend, 1918, which has been revised by O'Hara (1993) and belongs into the same tribe Goniini, but its described generic diagnostic characters (on page 12) cannot be used to distinguish Frontiniella beyond the Nearctic region. These characters are widely shared by Susamyia gen. nov. and other Palearctic genera Allophorocera Hendel, 1901, Brachicheta Rondani, 1861, Ceratochaetops Mesnil, 1970 Frontiniella: Compound eye sparsely to densely covered with ommatrichia; frons in male at its narrowest point 0.6-1.1 times as wide as an eye; male without outer orbital setae; frontal row of setae hair-like toward vertex; facial ridge with setae and fi ne setulae of diff erent sizes on at least half of its length; mid tibia with 1 anterodorsal seta; claw in male as long as tarsomere 5.
Susamyia gen. nov.: Compound eye bare, without ommatrichia; frons in male at its narrowest point 1.15-1.4 times as wide as an eye; both sexes with 2 strong proclinate outer orbital setae; frontal row of setae strong toward vertex; facial ridge with strongly erect setae on lower ⅔-¾; mid tibia with 2-3 strong anterodorsal setae in a row with further setae of diff erent sizes; claw in male short, 0.4 times as long as tarsomere 5.
In light of the Afrotropical tachinid literature, basically compiled in the works of Crosskey (1984) and O'Hara & Cerretti (2016), it is concluded that a strong morphological resemblance exists between our newly described genus and the recently described South African genus Myxophryxe Cerretti & O'Hara, 2016, although its male postabdomen and oviposition strategy remain to be described. Therefore, it is still unclear whether Myxophryxe belongs to Eryciini or the tribe Goniini in which Susamyia gen. nov. confi dently belongs to. Based on the description of Myxophryxe (O'Hara & Cerretti 2016), the following characters can be used to make a distinction between the two genera: Myxophryxe: Compound eye covered with thick, long ommatrichia (longest ommatrichia longer than diameter of fi ve eye facets); proclinate orbital setae absent in male; lower facial margin warped forward and more or less visible in lateral view; male postpedicel 3.9-6.3 times as long as pedicel; gena in profi le 0.25-0.50 times as high as compound eye; upper occiput with one row of black setulae; palpus slightly clavate.
Susamyia gen. nov.: Compound eye bare, without ommatrichia; both sexes with 2 strong proclinate outer orbital setae; lower facial margin not visible in lateral view; male postpedicel 6.5-7.5 times as long as pedicel; gena in profi le 0.17-0.21 times as high as compound eye; upper occiput with only pale hair-like setulae; palpus slender, cylindrical.
The Palearctic genus Gymnophryxe is found to be highly similar to Susamyia gen. nov. from which it is separated by the following characters (see also key 1 above): Gymnophryxe: Face 1.3-2.0 times as long as frons (Fig. 6F); frons more than 1.4 times as wide as one eye in dorsal view (Fig. 6H); usually 2-4 reclinate upper orbital setae present; apical scutellar setae inclined at 45-90° to horizontal; gena 0.3-0.5 times as high as vertical diameter of eye (Fig. 6F); surstylus of male terminalia in lateral view broader and shorter than cercus (Fig. 5D).
The strongest similarities occur between Susamyia gen. nov. and the genera Palesisa Villeneuve, 1929 (Palearctic) and Prosopodopsis Townsend, 1926 (Oriental, Afrotropical). Also the genera Dolichocolon Brauer & Bergenstamm, 1889 (Old World and Australasian, see Cerretti & Shima 2011) and Kuwanimyia Townsend, 1916(Southeast Palearctic, Oriental, Afrotropical, see Cerretti 2009) share a number of characters with Susamyia gen. nov., including strong affi nities between their male postabdomens: cerci not fused, widened, dorsoapically depressed, shorter than surstylus; surstylus straight, elongate and usually narrow (Fig. 8C-F). Additionally, they share the following characters: eye bare, facial ridge with a row of stout and erect setae over most of its length and parafacial entirely bare. All are members of the Goniini. It seems possible that this complex of morphological characters forms a monophyletic unit.
Palesisa: Fronto-orbital plate of male with 1-2 rows of more or less strong medioclinate setulae and few short and weak setulae outside frontal row (Fig. 8B); only females with two proclinate orbital setae; arista thickened at most at half of its length; lateral scutellar setae absent; epiphallus not diff erentiated (see also key 2 above).
Susamyia gen. nov.: Fronto-orbital plate of male with only a few hair-like black setulae outside the frontal setae (Fig. 8A); males and females with two proclinate orbital setae; arista thickened at least of two third on its length; lateral scutellar setae nearly as strong and long as basal setae; epiphallus diff erentiated.
Prosopodopsis: Two reclinate orbital setae, the uppermost of same size or weaker; section of wing vein M between crossveins r-m and dm-cu 1.0-1.2 times as long as section between crossvein dm-cu and bend of M, section of wing vein M between crossvein dm-cu and bend of M much longer than dm-cu; mid tibia with one strong anterodorsal seta in the middle of a row of several short setae; hind tibia with three dorsal preapical setae; epiphallus not diff erentiated; dorsal process of distiphallus not developed (see also key 1 above).
Susamyia gen. nov.: Usually one reclinate upper orbital seta, if sometimes two, the uppermost stronger; section of wing vein M between crossveins r-m and dm-cu 2.3-2.5 times as long as section between crossvein dm-cu and bend of M, section of wing vein M between crossvein dm-cu and bend of M shorter than dm-cu; mid tibia with two to three strong anterodorsal setae in a row of several short setae; hind tibia with two dorsal preapical setae; epiphallus diff erentiated; distiphallus with developed and sclerotized dorsal process.