Sylvalitoralis cheni Zhang, Bai & Yang, 2016

Zhang, Weiwei, Guo, Mingxia, Yang, Xingke & Bai, Ming, 2016, A new species of ice crawlers from Burmese amber (Insecta: Grylloblattodea), Zoological Systematics 41 (3), pp. 327-331 : 328-331

Sylvalitoralis cheni Zhang, Bai & Yang , sp. nov. ( Figs 1–4 )

Material examined. Holotype. Currently only one nearly complete specimen is known (No. BU-001678). This nymph male is designated as the holotype of the new species. It is currently housed in the Institute of Zoology , Chinese Academy of Sciences ( IZCAS), and will be eventually deposited in the Three Gorges Entomological Museum , Chongqing (specimen available for study by contacting MB or WWZ).

Etymology. This species is named in honor of the late Prof. Sicien Chen (Shixiang Chen), fellow of Chinese Academy of Sciences, former PI for the Group of Morphology and Evolution of Coleoptera, IZCAS. Prof. Chen was the founder and former director of IZCAS, and he made great contributions to entomological research of China.

Diagnosis. This new species can be attributed to Sylvalitoralis as follows: head large, with thick antennae; pronotum with weak paranota narrowing backward, less than twice as broad as head and as broad as mesonotum; middle and hind tibiae unarmed, directed backward; first tarsomere as long as third; abdominal tergites without paranota. It differs from the known species Sylvalitoralis by the shorter antennae, pronotum 0.75 times as long as wide, long legs and stronger metafemur.

Description. Male (holotype). Total body length 4.9 mm (measured from anterior margin of labrum to posterior margin of tenth abdominal segment). Body colored heavy orange-brown on head and thorax, lighter in color on abdominal segments, and covered with numerous short hairs ( Fig. 1 ).

Head attached obliquely to pronotum ( Figs 1–4 ). Cranium wider than long, with short setae on each lateral margin, longer setae around the antennal socket and near eye; epicranial suture partly preserved, not reaching the circumantennal suture. Eyes white, oval in shape ( Fig. 1 ). Antennae shorter than twice of head length, filiform, composed of at least 20 antennomeres, first segment about three times in length of second segment and two times in width.

Pronotum 0.75 times as long as wide, slightly concave in the posterior part, with long setae on the margins. Mesonotum and metanotum obviously concave in the posterior part, with long setae on the margins.

Legs elongate, with many scattered setae. Coxa with scattered setae and distinct ribs on the ventral part. Pro- and mesofemur with two rows of weak setae on the margins of ventral side; metafemur with two rows of long setae on the margins of ventral side. Protibia with dense and thin setae on ventral side; meso- and metatibia covered with many scattered setae, with long setae on outside; two large spines on the apical part of all tibiae. Only right metatarsi (first to third) preserved in the amber, with many long hairs, but the tarsal claws not preserved.

Abdominal tergites with lateral margin flexed to the posterior, 10-segmented, with long setae on the first to eighth tergites. Abdominal sternites with lateral margin flexed to the posterior, without setae. Cercomeres nine, cylindrical, with one ring pattern of setae on the distal part of all cercomeres except the 7th. Male genitalia badly preserved, obviously shrinking and in black color, probably carbonization.

Funding This research was supported by the National Science Fund for Fostering Talents in Basic Research (Special Subjects in Animal Taxonomy, NSFC-J 1210002), the Special Fiscal Funds of Shaanxi Province (2013-19), Research Equipment Development Project of Chinese Academy of Sciences ( YZ 201509), and by a Humboldt Fellowship (M.B.) from the Alexander von Humboldt Foundation.

Figures

Figures 1–2. Sylvalitoralis cheni Zhang, Bai & Yang, sp. nov., holotype (No. BU-001678). 1. Habitus photograph, lateral view. 2. 3D reconstructions based on µ-CT data. Abbreviations: ci—cerci; msn—mesonotum; mtf—metafemur; mtn—metanotum; mtt— metatibia; pn—pronotum. Scale bar=1mm.

Figures 3–4. 3D reconstructions of Sylvalitoralis cheni Zhang, Bai & Yang, sp. nov., holotype (No. BU-001678) based on µ-CT data. 3. Ventral view. 2. Head and thorax, dorsal view. Scale bar=1mm.