Research Article |
Corresponding author: Ren Dong ( rendong@mail.cnu.edu.cn ) Academic editor: Vladimir Blagoderov
© 2015 Jiaqi Gao, Shi Guifeng, ChungKun Shih, Ren Dong.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Gao J, Shi G, Shih C, Ren D (2015) Two new species of Paramesosciophilodes (Diptera, Nematocera, Mesosciophilidae) from the Middle Jurassic of China. ZooKeys 511: 117-129. https://doi.org/10.3897/zookeys.511.8425
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Two new species, Paramesosciophilodes bellus sp. n. and Paramesosciophilodes rarissima sp. n., from the Jiulongshan Formation at Daohugou Village, Inner Mongolia, China, are described in the extinct family Mesosciophilidae. Altogether seven genera with 21 species of mesosciophilids have been described from the Jurassic of Siberia and Kazakhstan, the Lower Cretaceous of Transbaikalia, and the Middle Jurassic of Inner Mongolia. An emended generic diagnosis of Paramesosciophilodes and a list of known taxa of mesosciophilids are provided.
Paramesosciophilodes , Daohugou, Inner Mongolia, China
Mesosciophilidae is one of the extinct dipteran families of the suborder Nematocera.
Genus | Species | Locality | Age |
---|---|---|---|
Mesosciophila | Mesosciophila venosa Rohdendorf, 1946 | Karatau, Chimkent Oblast, Kazakhstan | Karabastau Fm., J3 |
Mesosciophila eucalla Zhang, 2007 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Mesosciophila abstracta Zhang, 2008 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Mesosciophila sigmoidea Wang, Zhao & Ren, 2012 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Mesosciophilodes | Mesosciophilodes augustipennis Rohdendorf, 1946 | Karatau, Chimkent Oblast, Kazakhstan | Karabastau Fm., J3 |
Mesosciophilodes similis Rohdendorf, 1964 | Karatau, Chimkent Oblast, Kazakhstan | Karabastau Fm., J3 | |
Mesosciophilodes synchrona Zhang, 2008 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Mesosciophilina | Mesosciophilina bolshakovi Kovalev, 1985 | Siberia, Russia | Itat Fm., J2 |
Mesosciophilina irinae Kovalev, 1985 | Siberia, Russia | Itat Fm., J2 | |
Mesosciophilopsis | Mesosciophilopsis curtus Blagoderov, 1993 | Baissa, Buryat, Yeravnenskiy, Transbaikalia | Zaza Fm., K1 |
Mesosciophilopsis expletus Blagoderov, 1993 | Baissa, Buryat, Yeravnenskiy, Transbaikalia | Zaza Fm., K1 | |
Mesosciophilopsis minor Blagoderov, 1993 | Baissa, Buryat, Yeravnenskiy, Transbaikalia | Zaza Fm., K1 | |
Paramesosciophilodes | Paramesosciophilodes ningchengensis Zhang, 2007 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 |
Paramesosciophilodes eximia Zhang, 2008 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Paramesosciophilodes aequus Wang, Zhao & Ren, 2012 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Paramesosciophilodes bellus Gao, Shi, Shih & Ren, sp. n. | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Paramesosciophilodes rarissima Gao, Shi, Shih & Ren, sp. n. | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Jurasciophila | Jurasciophila curvula Li & Ren, 2009 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 |
Jurasciophila lepida Li & Ren, 2009 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 | |
Similsciophila | Similsciophila singularis Shi, Shih & Ren, 2014 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 |
Similsciophila sinuate Shi, Shih & Ren, 2014 | Daohugou, Ningcheng, Inner Mongolia, China | Jiulongshan Fm., J2 |
There have been many transfers and corrections regarding species belonging to the Mesosciophilidae. Eoboletina gracilis Rohdendorf, 1946 from the Upper Jurassic of Kazakhstan might belong to the family Mesosciophilidae (
Here, based on a combination of unique wing venational characters of two recently collected specimens, we describe Paramesosciophilodes bellus sp. n. and Paramesosciophilodes rarissima sp. n. These specimens with bodies and complete wings were collected from the late Middle Jurassic Jiulongshan Formation of Daohugou Village in the Ningcheng County, Chifeng City, southeastern Inner Mongolia, China. Many well-preserved fossil insects have been described from this locality recently (
This study is based on two specimens housed in the Key Lab of Insect Evolution & Environmental Changes, Capital Normal University, Beijing, China (Curator: Dong Ren). The specimens were examined under a LEICA MZ12.5 dissecting microscope. The photos of fossils were taken with a Nikon SMZ1000 stereo microscope. Line drawings were prepared with the aid of CorelDraw 12 graphic software. The method of calculating the ratio of cell r length vs. wing length is as follows: the length of cell r is the length along R1, while the length of wing is the length from wing base to wing apex. Wing venation nomenclature follows that of
Paramesosciophilodes ningchengensis Zhang, 2007.
Type species; Paramesosciophilodes eximia Zhang, 2008; Paramesosciophilodes aequus Wang, Zhao & Ren, 2012; Paramesosciophilodes bellus Gao, Shi, Shih & Ren sp. n., Paramesosciophilodes rarissima Gao, Shi, Shih & Ren, sp. n.
Medium (sized mesosciophilid gnats. Body (including legs) covered with long, dense pubescence. Mesonotum convex. Scutellum sharp, clearly projecting. Wing, Sc1 elongate, slightly shorter than one-half of wing length (0.43–0.47 times as long as wing length); Sc2 situated distinctly basad to Rs origin, arising near midway between h to Sc1 ending; bRs shorter than r-m; R1 slightly curved; both R1 and R4+5 divergent terminally; Rs furcated distad or at level of fork of M1+2; R2+3 oblique and curved; R4+5 arched near its midlength; cell r 0.16–0.19 times as long as wing length; stem of M not developed; M1+2 furcated slightly distad, or basad, to level of Sc1 ending. Tibiae and tarsi with sparse, short setae.
The specific name is from the Latin of bellus, meaning beautiful and delicate, for the well-preserved and beautiful specimen.
Holotype No. CNU-DIP-NN2013631 p/c, part and counterpart. A well-preserved insect with complete body and two wings but poorly preserved halter, without head, in dorsoventral aspect.
Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China, Jiulongshan Formation, late Middle Jurassic.
The Sc1 ending proximad of the midlength of cell r; bRs 0.7 times of the length of r-m; R4+5 strongly curved; M1+2 forking basad of forking of Rs, and distad of the level of Sc1 ending; CuA strongly arched, reaching the posterior margin of the wing markedly basad of Rs forking to R2+3 and R4+5.
Medium-sized mesosciophilid with dark body, adult male, in dorsal aspects (Figs
Wings membranous, oblong, darker in color in costal area, moderately wide (length 2.7 times of width), and not reaching the apex of abdomen at rest (Fig.
Paramesosciophilodes bellus sp. n. resembles most closely P. ningchengensis, but can be distinguished from the latter in having Sc1 ending at C proximad of the miglength of cell r (vs. at the miglength of cell r for P. ningchengensis) and CuA reaching the posterior margin of the wing markedly basad of Rs forking to R2+3 and R4+5 (vs. slightly basad of Rs forking to R2+3 and R4+5).
This new species is differentiated from P. ningchengensis, P. eximia, P. aequus, and P. rarissima sp. n. based on a combination of characters listed in Table
Comparison of seven key characters of five species of Paramesosciophilodes.
P. ningchengensis | P. eximia | P. aequus | P. bellus sp. n. | P. rarissima sp. n. | |
Length ratio of cell r and the wing | 0.167 (left wing) 0.180 (right wing) |
0.183 (left wing) 0.172 (right wing) |
0.22 as described. But, the missing wing base was not included in wing length measurement. | 0.165 | 0.184 |
Length of Sc1 | 46–47 % of the wing length | 46% of the wing length | 24% of the wing length as described. But, the missing wing base was not included in wing length measurement. | 46–47% of the wing length | 43% of the wing length |
Sc1 ending at C | at the midlength of cell r | distad of midlength of cell r | proximad of midlength of cell r | proximad of the midlength of cell r | near the midlength of cell r |
bRs vs r-m | 0.6–0.7 times of length of r-m | 0.5 times of the length of r-m | 0.9 times of the length r-m | 0.7 times of the length of r-m | 0.8 times of the length of r-m |
R4+5 | slightly curved | slightly curved | strongly curved | strongly curved | strongly curved |
The position of base of M1+2 forking vs the forking of Rs | M1+2 forking distinctly basad of forking of Rs | Ml+2 forking almost at level of forking of Rs | M1+2 forking basad of the forking of Rs | M1+2 forking basad of forking of Rs, | M1+2 forking basad of forking of Rs |
The position of base of M1+2 forking vs the level of Sc1 ending | M1+2 forking basad or distad of the level of Sc1 ending | M1+2 forking at the level of Scl ending | M1+2 forking distad of the level of the Sc1 ending | M1+2 forking slightly distad of the level of Sc1 ending | M1+2 forking slightly distad of the level of Sc1 ending |
CuA shape | CuA strongly arched | CuA smoothly arched | CuA smoothly arched | CuA strongly arched | CuA smoothly arched |
CuA ending at the posterior margin vs. Rs forking to R2+3 and R4+5 | CuA ending slightly basad of Rs forking to R2+3 and R4+5 | CuA ending slightly distad of Rs forking to R2+3 and R4+5 | CuA ending slightly distad of Rs forking to R2+3 and R4+5 | CuA ending markedly basad of Rs forking to R2+3 and R4+5 | CuA ending slightly distad of Rs forking to R2+3 and R4+5 |
The specific name is from the Latin word of rarissimus, meaning rare.
Holotype No. CNU-DIP-NN2013145 p/c, part and counterpart. A well-preserved insect with complete body with two wings, without head and halters, in dorsoventral aspect.
Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China, Jiulongshan Formation, late Middle Jurassic.
Sc1 ending near the midlength of cell r; bRs 0.8 times the r-m; R4+5 strongly curved; M1+2 forking basad of R2+3 level and distad of level of Sc1 ending at C; CuA strongly arched, reaching the posterior margin of the wing at the level of intersection of Rs forking to R2+3 and R4+5.
Medium-sized mesosciophilid gnats, in dorsal aspect (Figs
C strong, ending beyond wing apex, at which R4+5 ending (Fig.
Paramesosciophilodes rarissima sp. n. is distinguished from all other species of Paramesosciophilodes based on a combination of characters listed in Table
As shown in Table
The data show that the known earliest mesosciophilids have been reported from the Middle Jurassic, while the latest ones are described from the Early Cretaceous. It seems that mesosciophilids became less diverse in the Early Cretaceous, and were possibly replaced by Mycetophilidae (
We sincerely appreciate comments and suggestion from Dr. Blagoderov and two anonymous reviewers in improving this manuscript. We are grateful to Dr. Taiping Gao in the Key Lab of Capital Normal University for his valuable comments on the manuscript. This research is supported by National Basic Research Program of China (973 Program) (2012CB821906), the National Natural Science Foundation of China (No. 31230065, 41272006), Project of Great Wall Scholar of Beijing Municipal Commission of Education, Program for Changjiang Scholars and Innovative Research Team in University (IRT13081).