Lepidodexia, Brauer & Bergenstamm, 1891

Lepidodexia View in CoL clade

This clade is composed of the genera Halliosca , Emblemasoma and Lepidodexia (including Archimimus ). It received weak JK value and is supported by three autapomorphies: (1) paraphallic apical expansions present (‘pae’ in Figs 1B View Figure 1 , 9F View Figure 9 , 23A View Figure 23 , 31C View Figure 31 , 32F View Figure 32 ), (2) juxta squared, with an undulated distal margin ( Figs 9H View Figure 9 , 31H View Figure 31 , 32D View Figure 32 ) and (3) juxta displaced anteriorly ( Figs 31C, E View Figure 31 , 32A, F View Figure 32 ).

The species currently assigned to the genus Lepidodexia possess similarities in the phallic morphology, although their diversity in external morphology is remarkable ( Lopes, 1951, 1979, 1984, 1985, 1991, 1992). Some of these similarities were noticed by Roback (1954), who considered Camptops Aldrich , Chloronesia Townsend , Harpagopyga Aldrich , Johnsonia and Notochaeta to be phylogenetically close and placed them in the Johnsonia group. Roback (1954) also included Argoravinia , Emblemasoma and Helicobia in this group. Similarly, Lopes (1979, 1984) proposed the tribe Johnsoniini , where he included all the subgenera currently assigned to Lepidodexia plus some species currently in the genera Archimimus and Emdenimyia . The Johnsoniini of Lopes share character states of the head chaetotaxy, female terminalia, labrum of the first-instar larva and male terminalia structures such as the ‘spinous lobe of the vesica’ ( Lopes, 1979, 1984). Lopes (1983) also included Malacophagula and Rafaelia in the tribe Johnsoniini . Almost all the genera belonging to the Johnsoniini of Lopes were synonymized under Lepidodexia by Pape (1995, 1996), being characterized by the vesica bearing a proximal spinous lobe, and only excluding species of Archimimus and Emdenimyia , to produce a Lepidodexia ( sensu lato) containing 29 subgenera. Many of these are monospecific: Chloronesia , Cryptosarcophila , Halliosca , Neophytodes Townsend , Orodexia Townsend, Paramintho Brauer & Bergenstamm , Petriana Lopes and Stenopygopsis Townsend ; others include only a few species, for example Abacantha Hall , Dexomyophora , Eufletcherimyia Townsend, Geijskesia Lopes, Hallina and Travassosisca Lopes , while only six subgenera have numerous species, i.e. Chlorosarcophaga , Harpagopyga , Johnsonia, Lepidodexia , Neophyto and Notochaeta . Neither the genus Lepidodexia nor any of its subgenera have been recently revised. Only three phylogenetic studies have included species of this genus ( Lopes, 1984; Giroux et al., 2010; Kutty et al., 2010), and only one of these (Giroux et al., 2010) found Lepidodexia as monophyletic, although this clade was supported only by homoplasies. Thus, the monophyly of Lepidodexia and its subgenera had not been consistently tested, and there is no phylogenetic hypothesis for relationships within this genus.

In the present study, we included representative species of only six subgenera, i.e. Lepidodexia (Chlorosarcophaga) , L. ( Dexomyophora ), L. ( Hallina ), L. ( Halliosca ), L. ( Neophyto ) and L. ( Notochaeta ), of which all represented by more than one species emerged as monophyletic within a paraphyletic genus Lepidodexia ( Fig. 2B View Figure 2 ).

The only species of Halliosca emerges near the base of the Lepidodexia clade as it lacks the two autapomorphies that support this clade: (1) the presence of a hinge between the proximal and distal parts of the harpes [fused in Halliosca ( Fig. 31E, F View Figure 31 )], and (2) juxta angled [arching in Halliosca ( Fig. 31E View Figure 31 )]. Halliosca shows several character states shared with the genus Lipoptilocnema , including male abdominal ST5 with two pointed black cuticular processes on the angle of the V-shaped cleft, margin of surstylus overlapping the hinge between epandrium and surstylus, and cercal prong bent at mid-length, and with a proximal tuft of long black setae (identical to those of Lipoptilocnema ). As outlined above, Pape (1996) proposed a broadened concept of Lepidodexia ( sensu lato) containing 29 subgenera, one of these being Halliosca . The strong support found for a sister-group relationship between Emblemasoma and Lepidodexia (exclusive of Halliosca ) leaves two options: to exclude Halliosca as subgenus from the genus Lepidodexia ( Pape, 1996) , or to broaden the definition of the latter to include also Archimimus and Emblemasoma . We are here resurrecting Halliosca as a valid genus, new status.

Pape (1996) diagnosed Lepidodexia with three character states: (1) postalar wall bare, (2) distiphallus with juxta angled relative to the phallic tube ( Fig. 32A View Figure 32 ) and (3) distiphallus with a spinous lobe proximal to the vesica (no. 1 in Figs 31D View Figure 31 , 32C, F View Figure 32 ). Character state 1 is not particularly diagnostic for Lepidodexia , since it is shared only by the subgenera L. ( Neophyto ) and L. ( Notochaeta ). As mentioned above, character state 2 emerged as autapomorphic for clade 90, as it is shared by all members of the Lepidodexia clade except Halliosca ( Fig. 31E–G View Figure 31 ). Character state 3, originally described by Lopes (1979, 1984), is autapomorphic for clade 92, which consists of all subgenera of Lepidodexia (including Archimimus ), together with three uniquely derived synapomorphies: (1) arista almost twice as long as first flagellomere ( Fig. 44F View Figure 44 ), (2) male abdominal ST5 with a rounded expansion taking up the entire posterior half ( Fig. 44E View Figure 44 ), (3) vesica bipartite with a C-shaped medial section (no. 3 in Fig. 32C View Figure 32 ) and a convex sclerotized distal section (no. 2 in Fig. 32C View Figure 32 ). A comparison of the proximal spinous lobe of the vesica in various subgenera of Lepidodexia shows that this feature can be homologized across the genus (red structure in Fig. 33 View Figure 33 ). A monophyletic Lepidodexia can be attained by either raising all subgenera to valid genera, lumping all species into a Lepidodexia ( sensu lato), or a combination of the two. Following the last option, and in order to attain a monophyletic Lepidodexia , we choose to include Archimimus in this genus, as a subgenus, new status, and exclude Halliosca and give it the new status as a valid genus. This newly circumscribed Lepidodexia (including Archimimus ) received strong branch support and is supported by the conspicuous proximal spinous lobe of the vesica plus the above-mentioned autapomorphies.

The monophyly of and relationships between the subgenera of Lepidodexia are partially supported. Thus, L. ( Dexomyophora ) is supported by a facial ridge with dense setosity on lower 0.70 ( Fig. 46C View Figure 46 ), while L. ( Hallina ), L. ( Neophyto ) and L. ( Notochaeta ) are only supported by homoplasies.

Three out of five of the currently recognized species of Archimimus ( sensu Pape, 1996 ) are included in the present study, and they formed a strongly supported monophyletic group that emerged as sister to L. ( Neophyto ). The monophyly of L. ( Archimimus ) is supported by three autapomorphies: (1) pregonite distally spatulated, (2) median stylus truncated ( Fig. 9G View Figure 9 ) and (3) median stylus with no opening ( Fig. 9G View Figure 9 ). Only five genera and one subgenus of Sarcophaginae have the median stylus strongly modified into an apparently non-conducting stylus or entirely reduced. These are L. ( Archimimus ), Chrysagria , Helicobia , Lipoptilocnema , Peckia and Sarcophaga , and all are characterized by different acrophallic configurations. Lepidodexia (Archimimus) and Lipoptilocnema have both a median stylus and a capitis, but the median stylus is not tubular ( Figs 9G View Figure 9 , 24B–I View Figure 24 ); Chrysagria has a short capitis and an entirely reduced median stylus ( Fig. 11C View Figure 11 ); Helicobia and Sarcophaga have an elongated capitis and an entirely reduced median stylus ( Fig. 37C, G View Figure 37 ); and Peckia has no trace of either a median stylus or a capitis ( Figs 12H View Figure 12 , 13H View Figure 13 ). The sister-group relationship between L. ( Archimimus ) and L. ( Neophyto ) is supported by one autapomorphy: distance between occiput and antennal base longer than distance between occiput and vibrissal angle.

Roback (1954) included Emblemasoma in the Johnsonia group, and considered it to be closely related to Helicobia and Johnsonia (= Lepidodexia , in part) due to structural similarities in the male terminalia. Emblemasoma was considered as part of the tribe Sarcophagini by Lopes (1969a), but Lopes (1983) later erected the tribe Emblemasomatini for Emblemasoma and Pessoamyia Lopes. Our results support these assumptions, since Emblemasoma is closely related to Lepidodexia , as suggested by Roback (1954), and species originally in Emblemasoma and Pessoamyia constitute a monophylum, as indicated by Lopes (1969a). Lopes (1971) defined Emblemasoma and Pessoamyia by the presence of an inflated prosternum. Pape (1996) synonymized these two genera and expanded the definition of Emblemasoma , which he diagnosed as follows: (1) prosternum enlarged, (2) male mid-femur with a ctenidium of rounded spines (circular cross section) and (3) male cercus distally swollen and with a blunt tip ( Fig. 44G View Figure 44 ). Here, the monophyly of Emblemasoma was tested for the first time, and it is supported by seven autapomorphies, mostly from non-terminalia characters. These include character states 1 and 3 of Pape (1996), plus facial plate almost equibroad along its entire length ( Fig. 44A View Figure 44 ), parafacial plate widest at level of lunule ( Fig. 44B View Figure 44 ), palpus with long setae ( Fig. 44B View Figure 44 ), male mid-femur with 1–4 antero-dorsal setae at mid-length and vesica composed of two leaf-shaped lobes ( Fig. 23A–E View Figure 23 ).