Cretorhadalus Kolibac & Prokop, 2023

Kolibac, Jiri, Rosova, Katerina, Prazak, Jan Simon, Hammel, Joerg U. & Prokop, Jakub, 2023, The first larva of the cucujiform superfamily Cleroidea from the Mesozoic and its ecological implications (Coleoptera), Arthropod Systematics & amp; Phylogeny 81, pp. 289-301 : 289

Cretorhadalus Kolibac & Prokop gen. nov.

Type species.

Cretorhadalus constantini Kolibáč & Prokop gen. et sp. nov.

Diagnosis.

Cranium weakly trapezoidal, approximately as wide as long, its anterior margin wider than base (Figs 1C , 4C ); head capsule ventrally open, with long gular sutures (Figs 1D , 5 ); five stemmata present on each side, with formula 2+3 (Fig. 2C, D ); terminal antennomere slender and longer than the previous one (Figs 2D , 5 ); dorsal side of prothorax with single sclerotized tergal plate divided longitudinally with suture; meso- and metatergum with a pair of distinct tergites (Fig. 1A, C ); urogomphi slender, hooked (Fig. 1E ), without distinct glandular openings, processes or tubercles (a pair of membranous appendages might be present at centre of abdominal tergite 9).

Etymology.

The generic name is composed of the prefix creto - (derived from Cretaceous period) and the root rhadalus that denotes the supposed affiliation of the new genus with the family Rhadalidae , not a relationship with the nominate genus. Gender of name is masculine.

Figures

Figure 1. Cretorhadalus constantini gen. et sp. nov.: A Habitus, dorsal view. B Habitus, ventrolateral view. C Head and thorax, dorsal view. D Urogomphi, dorsolateral view. E Head, ventral view.

Figure 2. Cretorhadalus constantini gen. et sp. nov., X-ray μCT renderings: A Head and thorax, anterior and / or ventral view. B Head, ventral view. C Head, anterior view. D Head, dorsolateral view. E Mandibles, ventral view. F Habitus, dorsal view (without segment IX).

Figure 4. Comparison of frontal sutures and shapes of cranium: A Phycosecis (Phycosecidae). B Danacea (Dasytidae). C Cretorhadalus constantini gen. et sp. nov. D Aplocnemus (Rhadalidae).

Figure 5. Maxillolabial complex of Cretorhadalus constantini gen. et sp. nov. Dotted lines indicate indistinct margins. Cranium apparently compressed and its ventral side artificially wide open; that is why gular sutures seem divergent and widely separated. The length of the gular sutures is not clear.