Dexosarcophaga grade, Lopes, 1953

Dexosarcophaga grade

This grade is composed of the genera Dexosarcophaga (including Cistudinomyia ), Oxyvinia and Rettenmeyerina (clade 21 and Rettenmeyerina in Fig. 2A View Figure 2 ). These four genera share two character states: vesical arm-shaped lever gently angled (green in Fig. 26B View Figure 26 ), and distal section of the vesica bifid and not particularly ornamented (yellow structure in Figs 25H View Figure 25 , 26 View Figure 26 ). The clade ( Oxyvinia + Dexosarcophaga [including Cistudinomyia ]) ( Fig. 2A View Figure 2 ) received a weak JK value. This clade is supported by the homoplasious character state ‘ctenidium of rounded spines present’ and two autapomorphies: occipital setulae above occipital foramen black, and hillae long and spoon-shaped, with a squared apex. The genera Oxyvinia and Dexosarcophaga (including Cistudinomyia ), as well as the clade combining the two, all received weak branch support.

Roback (1954) considered Cistudinomyia as part of the subtribe Raviniina, Dodge (1968b) considered Dexosarcophaga as closely related to Oxysarcodexia , while Lopes (1969a, 1975b, 1983) did not include Cistudinomyia in his tribal array of the Sarcophaginae , but he placed Dexosarcophaga in the tribe Cuculomyiina , Oxyvinia in Raviniini and Rettenmeyerina in Sarothromyiini . Giroux et al. (2010) included Cistudinomyia , Dexosarcophaga and Oxyvinia in their taxon sample and found a weakly supported clade (( Dexosarcophaga + Oxyvinia ) + ( Cistudinomyia + other Sarcophaginae )) using morphological characters. The molecular studies of Kutty et al. (2010) and Piwczyński et al. (2014) included Dexosarcophaga and recovered the topologies ( Dexosarcophaga + ( Argoravinia + Blaesoxipha )) and ( Dexosarcophaga + Argoravinia ), respectively, both with low branch support.

Lopes (1969a) placed Rettenmeyerina together with Bahamiola , Sarcofahrtiopsis and Tricharaea in the tribe Sarothromyiini on the basis of these genera sharing proclinate fronto-orbital setae in the male. Here, Rettenmeyerina is diagnosed only by homoplasies, as we found no autapomorphies for this genus. The presence of a desclerotized area between the paraphallus and the juxta in Rettenmeyerina is relevant for defining this genus. Rettenmeyerina emerges as sister taxon to the remaining ‘higher’ Sarcophaginae , which has ( Oxyvinia + Dexosarcophaga [including Cistudinomyia ]) as sister clade of the remaining Sarcophaginae species ( Fig. 2A View Figure 2 ). The presence of proclinate fronto-orbital setae in the male is a plesiomorphic feature in the Tricharaea grade , which means that the absence of male proclinate fronto-orbital setae in the ancestor of the ‘higher’ sarcophagines (excl. of Rettenmeyerina ) has to be considered an apomorphic reversal. Male proclinate fronto-orbital setae, i.e. male and female with the same frontal chaetotaxy, are of very sporadic occurrence in the Calyptratae, and there is to our knowledge no other instance where the presence of male proclinate orbital setae has been hypothesized as a reversal.

Oxyvinia View in CoL was monophyletic in our analysis, but its JK supports were low ( Fig. 2A View Figure 2 ). One autapomorphy supports this genus: paraphallus bent ventrally in its proximal third ( Fig. 19B View Figure 19 ). Different placements of Oxyvinia View in CoL by different authors are due to the use of different character systems. For example, Lopes (1983) considered Oxyvinia View in CoL as closely related to Ravinia View in CoL and Oxysarcodexia View in CoL because these three genera share the festoon-like larval oral ridges (Leite & Lopes, 1987), while Giroux et al. (2010) found a sister-group relationship between Dexosarcophaga View in CoL and Oxyvinia View in CoL supported by adult character states. Our diagnosis of Oxyvinia View in CoL is in agreement with the one proposed by Pape (1996) for this genus, except that we define the juxta differently and therefore consider it as present.

The clade composed of Dexosarcophaga View in CoL (including Cistudinomyia ) showed weak branch support in our analysis ( Fig. 2A View Figure 2 ). The branch support value for Dexosarcophaga View in CoL (s.s.), i.e. excluding Cistudinomyia , was stronger than those supporting its sister-group relationship with the monospecific Cistudinomyia . One autapomorphy supported the clade of Dexosarcophaga View in CoL (including Cistudinomyia ): pregonite C-shaped (see figs in Mello-Patiu & Pape, 2000). Different interpretations of the connection between basiphallus and distiphallus of Cistudinomyia have led to different phylogenetic positions of this genus in available studies, as highlighted by Giroux et al. (2010). Roback (1954) included Cistudinomyia , Ravinia View in CoL and Oxysarcodexia View in CoL in the subtribe Raviniina based on these genera having no clear demarcation between basiphallus and distiphallus, as well as sharing other similarities in the shape of ST5. Pape (1994) recovered ( Tricharaea View in CoL ( Cistudinomyia + remaining Sarcophaginae View in CoL )) and considered Cistudinomyia as having a distinct desclerotized strip between basi- and distiphallus. Here, we scored Cistudinomyia as bearing a hinge between basi- and distiphallus ( Fig. 11D View Figure 11 ), a condition shared with its sister group, Dexosarcophaga View in CoL (s.s.). Except for one character state, Cistudinomyia possesses all features cited in the latest diagnosis of Dexosarcophaga View in CoL , provided by Mello-Patiu & Pape (2000). The exception corresponds to the colour of the terminalia, red in Cistudinomyia and blackish in Dexosarcophaga View in CoL (s.s.). Based on the autapomorphies of the clade of Dexosarcophaga View in CoL (including Cistudinomyia ), we suggest Cistudinomyia as a new synonym of Dexosarcophaga View in CoL . We have chosen to maintain Cistudinomyia as a subgenus, and our new diagnosis for Dexosarcophaga View in CoL accordingly also includes Cistudinomyia as a subgenus, new status.