Saurophthirus laevigatus Zhang, Shih, Rasnitsyn, and Gao, 2020

Gao, Taiping, 2020, A new Early Cretaceous flea from China, Acta Palaeontologica Polonica 65 (1), pp. 99-107 : 101-103

publication ID	https://doi.org/ 10.4202/app.00680.2019
DOI	https://doi.org/10.5281/zenodo.10987247
persistent identifier	https://treatment.plazi.org/id/9E4887CB-DF68-A170-FCA7-FA21D6D3F93B
treatment provided by	Felipe
scientific name	Saurophthirus laevigatus Zhang, Shih, Rasnitsyn, and Gao
status	sp. nov.

Treatment

Saurophthirus laevigatus Zhang, Shih, Rasnitsyn, and Gao View in CoL sp. nov.

Figs. 1 View Fig , 2 View Fig .

ZooBank LSID: urn:lsid:zoobank.org:act:9765D35B-87CD-4BFF-9AFB-39957267FB6D

Etymology: From Latin laevigatus , smooth.

Type material: Holotype: No. CNU-SIP-LL2015001p/c, a complete male with part and counterpart.

Type locality: Dawangzhangzi Village , Lingyuan City, Liaoning Province, China .

Type horizon: Yixian Formation , Early Aptian, Lower Cretaceous .

Diagnosis.—Male body almost perfectly fusiform (not distinctly attenuate rearward), of medium size (ca. 10 mm); head length longer than width; antenna with approximately 17 segments with flagellomeres compact disc-shaped, not distinctly widened before apex; body and legs with short bristles and setae; legs nearly as long as body, hind coxae elongated, hind femur 0.35 as long as body; male genitalia partially retracted, 0.3 times as long as body.

Description.—Male ( Fig. 1A 1, B 1 View Fig ), 9.8 mm long excluding antennae, almost completely-preserved ventral view, slightly dorsoventrally compressed.

Head Helmet-like, relatively small, 1.20 mm wide, 0.89 mm high; antenna with approximately 17 segments, overall length 1.60 mm, flagellomeres uniform in shape, basal thinner, generally widening, broadest at middle section, narrow at apex ( Fig. 1A View Fig 2 View Fig ); the compact disc-shaped flagellomeres slightly compressed and the last two segments smaller. Piercing-sucking mouthparts about 0.51 mm long (as preserved), extending to pro-coxae; existing laciniae but the tip of beak invisible ( Fig. 2A View Fig 1 View Fig , A 2 View Fig , B 1 View Fig ).

Thorax: Relatively small and without wings, prothorax narrower than mesothorax, mesothorax narrower than metathorax; prothorax approximately twice as long as metathorax. Legs slender, coxae slightly enlarged and with prominent bristles ( Fig. 2A View Fig 3 View Fig ), hind coxae approaching each other and the length twice as long as the fore and mid coxae; the length of each femur 1.4 times as long as tibiae, lengths obviously increasing from fore to hind femur and tibiae, particularly on femur; hind femur thinner than middle femur, much thinner than fore femur; tibiae specialized, basal narrow but gradually widened toward apex ( Fig. 2A View Fig 4); tarsus with five segments; basitarsus equal to the following two tarsal segments combined; fourth tarsal segment shortest, fifth tarsal segment nearly equal to the second one; pretarsus with a pair of large scythe-shaped claws.

Abdomen: Eight segments and the fourth segment widest; the width of sternites I– VI subequal in length; sternites weakly sclerotized.

Genitalia: Male genitalia long, extending far beyond the body, with gonocoxa and gonostylus; the width of abdominal I– VI segments equal, VIII segment distinct shortened to 1/2 of I– VI segments, the width of abdominal IX–X segments nearly equal to abdominal I– VI segments; gonostylus and external part of gonocoxa equal to each abdominal segment ( Fig. 1A View Fig 4, A 5); visible (external) part of aedeagus wide and with long setae, gonostylus and the external part of the gonocaxa with subequal lengths, the apex of gonostylus closed inward and almost complete package the aedeagus ( Fig. 1A View Fig 4, A 5). The setae of body lost, only a few short and stout bristles preserved on the basal section of the fore leg, and the relatively sparse setae attached to the aedeagus, probably due to poor preservation ( Fig. 1B View Fig 2 View Fig , B 3 View Fig ).

Remarks. —The new species is distinguished from male S. longipes Ponomarenko, 1976 ( Fig. 3 View Fig ) never described before (except for male genitalia) ( Rasnitsyn 1992) and S. exquisitus Gao, Shih, Rasnitsyn, and Ren 2013 by fusiform body not distinctly attenuate rearward, short vestiture of legs and body and relatively short legs (hind femur 0.35 rather than 0.45–0.48 times as long as body) and genitalia (0.3 rather than 0.35–0.4 times as long as body). Additionally, it differs from S. longipes by 17-segmented antenna (not more than 15 in S. longipes ), from S. exquisitus by antenna widest well before apex (distinctly widest near apex in S. exquisitus ), with compact disc-shaped flagellomeres (more elongate in S. exquisitus ).