Predators or Herbivores: Cockroaches of Manipulatoridae Revisited with a New Genus from Cretaceous Myanmar Amber (Dictyoptera: Blattaria: Corydioidea)

Abstract

Manipulator modificaputis Vršanský and Bechly, 2015 (Manipulatoridae, Corydioidea) is a purported predatory cockroach from Cretaceous Myanmar amber, based on a single male. It is distinctive by the nimble head, elongate pronotum and legs, and particularly by the extraordinarily long maxillary palpi. In the present study, we redescribe Manipulator modificaputis based on six new fossils including males and females, and comment on the original description. The closely related Manipulatoides obscura gen. & sp. nov. is proposed on the basis of five fossils, including males and females. It differs from Manipulator in weaker spination of the legs, including the type-C forefemoral spination instead of the type-A of Manipulator. Some undetermined adults and nymphs are also described. We discuss the ethology of Manipulatoridae and speculate that they might feed on flowers. They are unlikely to be specialized predators since they lack necessary weaponry for capturing prey; in contrast, their unique morphotype appears to be suitable for efficient foraging and locomotion amid flowering twigs. The possibility of being kleptoparasites of the spider-web is also discussed. In addition, regenerated four-segmented tarsi are found from the new species.

Atypical ‘long-tailed’ cockroaches arose during Cretaceous in response to angiosperm terrestrial revolution

“…, plant litter, crevices and burrows), which are, as shelters, preferred by most extant cockroaches. Their habitus is reminiscent of fossil cockroach families Raphidiomimidae and Manipulatoridae, and extant cockroach genus Saltoblattella : Raphidiomimidae have elongate and prognathous head and might be predators ( Vishnyakova, 1973 ; Vršanský, Vishniakova & Rasnitsyn, 2002 ; Grimaldi & Engel, 2005 ; Liang, Vršanský & Ren, 2012 ; Liang, Shih & Ren, 2017 ), Manipulatoridae have exceptionally long appendages (antennae and maxillary palpi in particular) and might be flower-visiting herbivores ( Li & Huang, 2022 ; but see Vršanský & Bechly, 2015 ), and Saltoblattella is a jumping cockroach with well-developed saltatorial legs ( Bohn et al, 2010 ). Their assumed habits have associations with open habitats.…”

“…Beetle-like fossil cockroaches are represented by Umenocoleidae and Cratovitismidae ( Bechly, 2007 ; Lee, 2016 ; Beutel, Luo & Wipfler, 2020 ; Luo, Xu & Jarzembowski, 2020 ; Luo et al, 2021 ; Luo et al, 2022 ), which are comparable with extant Diploptera cockroaches in exposed head, smaller pronotum, and heavily sclerotized forewings (especially D. maculata and D. elliptica , see Li & Wang, 2015 ; Li, Li & Wang, 2017 ). Fossil cockroaches with elongate and agile appearance are represented by Raphidiomimidae and Manipulatoridae ( Vishnyakova, 1973 ; Liang, Vršanský & Ren, 2012 ; Vršanský & Bechly, 2015 ; Li & Huang, 2022 ), which have elongate head and appendages in addition to the long body build. In spite of some debates, little is known about the habits and habitats of these atypical fossil cockroaches.…”