Denaeostephanus chaofeng, Ge & Jiang & Ren & van Achterberg & Tan, 2023

Ge, Si-Xun, Jiang, Zhuo-Heng, Ren, Li-Li, van Achterberg, Cornelis & Tan, Jiang-Li, 2023, New insights into the phylogeny of Stephanidae (Hymenoptera: Apocrita), with a revision of the fossil species, Arthropod Systematics & amp; Phylogeny 81, pp. 819-844 : 819

† Denaeostephanus chaofeng sp. nov.

Figures 14 , 15

Holotype.

♀; BFU, Baltic amber, Eocene. Part of Si-Xun Ge’s collection

Etymology.

The new species was named after the third son of the Loong in Chinese mythology as the third species of † Denaeostephanus .

Diagnosis.

Pronotum comparatively robust, neck without distinct pronotal fold; anterior, middle and posterior part of pronotum almost at the same level in lateral view; mesonotum at the same level of pronotum; forewing with vein 1-M arched; vein 2Rs+M extremely short; vein 2Cua and 2Cub nebulous; hind femur relatively slender (Fig. 15D ), minor teeth between basal and distal large tooth rather weakly developed; tergum I and sternum I fused (Fig. 14C ; Fig. 15C ), tergite I elongated as about 0.5 × as long as remainder of metasoma.

Description.

Description: Female. Total body length (without ovipositor sheath) 3.6 mm; forewing length ca. 2.4 mm; ovipositor sheath 2.9 mm. - Head: Antenna with 19 flagellomeres; the first flagellomere short and robust while the second is elongated and slender; Head sub-globular (probably more or less traverse in dorsal view), with compound eyes occupying most part of lateral surface; vertex with five acute and triangular tubercles; temple comparatively flat, coriaceous; occipital carina distinctly developed and connected to hypostomal flange; hypostomal flange strong, without distinct rugae. Maxillary palpus 5-segmented, elbowed between MP II (maxillary palpomere II) and MP III; MP I and MP II distinctly short and strong, MP III-V long and slender; MP III slightly less than twice length of MP IV and MP V. - Mesosoma: Pronotum robust; neck without distinct pronotal fold; neck at almost same level of middle part of pronotum postero-dorsally; middle and posterior part of pronotum coriaceous, with slightly transverse carinae; middle part of pronotum not distinctly differentiated from posterior part; mesonotum at the same level of pronotum, without setosity; propleuron and mesopleuron coriaceous or imbricate; propodeum with its lateral view micro-sculptured; scutellum invisible. - Wings: Forewing with vein 1-M distinctly curved, 2.9 × as long as vein 1-Rs and 1.7 × vein 1m-cu; vein 2-Rs long, ca. 3.8 × as long as vein r-rs; vein r-rs ends inner side of pterostigma behind the level of apex of pterostigma; parastigmal vein (pv) ca 0.4 × as long as pterostigma; vein 2Rs+M (= Rs+Mb) extremely short, with its apical slightly incision at the origin of veins 2-Rs and apical abscissa of vein M; vein 2Cua and 2Cub nebulous. - Legs: Hind coxa comparatively slender, coriaceous, spindle shaped without transversely striate; hind femur coriaceous, relatively slender; ventral surface of hind femur bidentate, with its widest tooth developed at near 0.35 × as its basal part; a more acute triangular tooth developed near 0.3 × as its distal part with two small teeth behind, only one minor tooth weakly developed behind the basal large tooth; hind tibia about 1.2 × as long as hind femur, with its basal narrow part as equal length as apical widened part, inner side of widened part basally moderately depressed; hind tarsus with five tarsomeres; basitarsus rather elongate, slightly longer than the length of all other tarsomeres. - Metasoma: Tergite I elongated and about 0.5 × as long as the remainder of metasoma; tergite I with its ventral length 3.0 × its maximum width; pygidial area not protruding apically; ovipositor sheath ca 0.8 × as long as total body length and 1.2 × as long as forewing length. Ovipositor tip laterally compressed, without distinct teeth apically.

Remarks.

Two † Denaeostephanus species, † D. sulcatus (Aguiar and Jazen, 1999) and † D. tridentatus (Brues, 1933), have been recognized before and only males have been described. This is also the first discovery of a female belonging to the genus, and thus we could supplement key characteristics of † Denaeostephanus in phylogenetic research, such as the 5-segmented hind tarsus. Obviously, the single voucher specimen corrected the speculation of the 3-segmented hind tarsus by van Achterberg (2002). According to our phylogenetic analysis, † Denaeostephanus belongs to the subfamily Stephaninae and is a sister to all extant genera of the subfamily.

Figures

Figure 14. Denaeostephanus chaofeng Ge and Tan, sp. nov. Holotype ♀. A Photo of specimen. B Line drawing of habitus. C Metasoma, lateral view. D Hind leg.

Figure 15. Details of Denaeostephanus chaofeng Ge and Tan, sp. nov. Holotype ♀. A Head, frontal-oblique view. B Wings. C Metasoma. D Hind leg.