Requenini, Rentz, 2001

Mugleston, Joseph D., Naegle, Michael, Song, Hojun & Whiting, Michael F., 2018, A Comprehensive Phylogeny of Tettigoniidae (Orthoptera: Ensifera) Reveals Extensive Ecomorph Convergence and Widespread Taxonomic Incongruence, Insect Systematics and Diversity (AIFB) 2 (4), No. 5, pp. 1-27 : 23

Requenini , Hexacentrinae , Meconematini , Nedubini, Phisidini , Arytropteridini, and Hetrodinae

This large and taxonomically jumbled subclade contains taxa currently described under five subfamilies ( Fig. 14 ). An early split in this subclade gave rise to the monophyletic Hexacentrinae and the Australian tribe Requenini . The relationship of Requena and other katydids has been contested with Rentz (2001) including Requenini as a tribe within Listroscelidinae —a position that it holds today.This position was questioned by Gorochov (2007) who concluded the placement of this tribe is unclear.Additional work is required to determine whether Requenini is an aberrant tribe within Hexacentrinae , or a unique subfamily sister to the Hexacentrinae . However, it is evident that Requenini is neither Conocephalinae nor is it closely related to other taxa currently described as Listroscelidinae and should not be included in either. In agreement with prior analyses, Hexacentrinae was supported as monophyletic. The position of Hexacentrinae has been disputed in the past with some placing this subfamily as a tribe within Conocephalinae ( Gorochov 1995a) , or Listroscelidinae ( Rentz 1996, 2001). Recently, attention has shifted to the relationship between this subfamily and the other katydids. Gorochov (2007) posited a sister relationship between

Hexacentrinae and Conocephalinae though our results do not support this. The monophyly of the remaining Tettigoniinae group is largely congruent with biogeography. For instance, Meconematini has an Indomalayan and Palearctic distribution. This tribe was thought to be closely related to Phisidini based on stridulatory structure ( Gorochov 2007) but the two tribes were not found to be sister. Instead, the Australasian and Malagasy Phisidini is sister to the Australian shieldback katydids Rhachidorus . The tribes within Meconematinae do not form a monophyletic group and represent at least three distinct lineages that have converged to similar morphologies. Meconematinae is paraphyletic and should no longer be considered a valid group in current taxonomy. The remaining lineages in this clade comprise the African Hetrodinae and their sister taxon, the African shieldback tribe Arytropteridini . Currently, Arytropteridini is considered a tribe in Tettigoniinae , but these results put the tribe as a separate subfamily, or an aberrant lineage of Hetrodinae . Arytropteridini and Rhachidorus (traditionally considered lineage of the tribe Nedubini ) further support the earlier claim that the southern hemisphere Tettigoniinae represent convergent ecomorphs with the Holarctic shieldback katydids or represent a relict form shared with the other species traditionally considered Tettigoniinae . Further investigation into the lineages of the paraphyletic Nedubini is necessary to determine how these taxa are related. In light of the findings here, and in Cole and Chiang (2016), it is apparent that Nedubini is not a monophyletic tribe and the taxa currently described within this tribe should not be included within Tettigoniinae .

Figures

Fig. 14. Tettigoniinae group: Requenini, Hexacentrinae, Meconematini, Australian Nedubini, Phisidini (sans Arachnoscelis), Arytropteridini, and Hetrodinae. Vertical bars indicate subtribes, tribes, and subfamilies. Paraphyletic groups are marked with an asterisk. Posterior probability values over 90 are marked with a circle at the node. Photo credits are as follows: (Hexacentrus sp.) (Serville, 1831) Hojun Song, (Oediphisis sp.) (Jin, 1992) Arthur Anker, (Hetrodes sp.) (Fischer vonWaldheim, 1833) Joseph Mugleston.