Neimengornis rectusmim gen. et sp. nov (1 Viewer)

[albertonykus]

Wang, J.Y., X.R. Wang, B. Guo, A. Kang, F.M. Ma, and S.B. Ju (2021)
A new jeholornithiform identified from the Early Cretaceous Jiufotang Formation in western Liaoning
Geological Bulletin of China 40: 1419–1427

A new specimen of jeholornithiform was identified from the Early Cretaceous Jiufotang Formation in Chaoyang of Liaoning Province. This specimen shows typical characters of Jeholornithiformes, such as the long bony tail composed of about 28 free caudal vertebrae, the middle and posterior caudal vertebrae elongated antero-posteriorly, the edentulous premaxilla, and the dentary with a straight ventral margin posteriorly and a robust anterior end expanded ventrally. It differs from all other jeholornithiforms in the following unique combination of features: the relatively undeveloped deltopectoral crest of the humerus, the straight third metacarpal, which forming a small gap with the second metacarpal, the largest hallux ungula [sic], and the undeveloped chevrons and zygapophyses of the caudal vertebrae. On the basis of unique characteristics and comparisons with other jeholornithiforms, a new genus and species (Neimengornis rectusmim gen. et sp. nov.) were erected. The identification of Neimengornis rectusmim further enriches the diversity of jeholornithiforms and sheds new light on understanding the morphology and classification of this clade.

 

[l_raty]

In addition to the OD itself, there is also a reconstitution on the front cover of this issue:

http://dzhtb.cgs.cn/uploadfile/cover/gbc/2021_9_small.jpg

 

[Fred Ruhe]

Unfortunately, the paper is entirely in Chinese, except for the English abstract. As my Chinese is a little bit rusty (not existing) I cannot give much details on this new species. But I give what I can.

Systematic paleontology

恐龙类 Dinosauria Owen, 1842
兽脚类 Theropoda sensu Gauthier, 1986
手盗龙类 Maniraptora Gauthier 1986
初鸟类 Avialae Gauthier, 1986
热河鸟目 Jeholornithiformes Zhou et Zhang, 2007
内蒙鸟(新属) Neimengornis gen. nov.
模式种: 直掌内蒙鸟 Neimengornis rectusmim sp. nov.

That is all I can give. Perhaps Albert or Laurent who both know a lot more of the Chinese language than I do can give more information like the diagnosis, the locus typicus, the etymology etc.

Fred


Fig. 1: Photograph (A) and Line drawing (B) of the holotype of Neimengornis rectusmim gen. et sp. nov,

 

[l_raty]

Perhaps Albert or Laurent who both know a lot more of the Chinese language than I do can give more information like the diagnosis, the locus typicus, the etymology etc.

Somewhat reworked Google translations of the most relevant paragraphs below. I don't exactly speak or read Chinese either, hence there are certainly imperfections.

词源: 属名由汉语拼音 “Neimeng” (内蒙) 和希腊语 “ornis” (鸟) 组成, 指模式标本收藏于内蒙古自然博物馆。种名由拉丁语 “rectus” (直的) 和英语 “minor metacarpal” 缩写 “mim” (小掌骨) 组成。指模式标本具有直的小掌骨, 明显不同于其他热河鸟类。​

[Etymology: The genus name is composed of the Chinese pinyin "Neimeng" (Inner Mongolia) and the Greek "ornis" (bird), in reference to the type specimen being stored in the Inner Mongolia Natural Museum. The species name is composed of the Latin "rectus" (straight) and the English "minor metacarpal" (minor metacarpal bone) abbreviated to "mim". This refers to the type specimen having straight minor metacarpals, which is obviously different from other Jehol birds.]

鉴定特征: 前后肢长度比为 1.09 (其他热河鸟类此比值在 1.2~1.35 之间); 肱骨三角肌脊延伸至肱骨骨干的 27% (其他热河鸟类约达到 40%); 第三掌骨较直, 与第二掌骨间距较小 (其他热河鸟类第三掌骨呈弓形弯曲, 与第二掌骨间距较大); 中后部尾椎脉弧和关节突发育不明显 (其他热河鸟类中后部尾椎脉弧和关节突均发育明显且前后拉长); 第一趾爪最大 (其他热河鸟类第二趾爪最大, 或第二、三趾爪近等大)。​

[Identification features: The ratio of the lengths of the front and rear limbs is 1.09 (for other Jehol birds, this ratio is between 1.2 and 1.35); the deltopectoral crest of the humerus extends to 27% of the humeral diaphysis (about 40% in other Jehol birds); the third metacarpal is relatively straight, and forms a small gap with the second metacarpal (other Jehol birds have an arched and curved third metacarpal and a larger gap with the second metacarpal); the chevrons and zygapophyses of middle and posterior caudal vertebrae are not obviously developed (in other Jehol birds, the posterior caudal chevrons and zygapophyses are clearly developed and elongated antero-posteriorly); the first toe is largest (other Jehol birds have the second toe largest, or the second and third toes nearly as large).]

正型标本: 1 件近完整并关联保存的独板鸟类化石标本, 保存于内蒙古自然博物馆。标本馆藏号 IMMNH -PV00122 (图 1; 表 1)。​

[Type specimen: One nearly complete fossil specimen preserved as a single plate, stored in the Inner Mongolia Natural Museum. Specimen collection number IMMNH-PV00122 (Figure 1; Table 1).]

产地层位: 辽宁省朝阳市大平房化石点,早白垩世九佛堂组。​

[Origin: Fossil site of Dapingfang, Chaoyang City, Liaoning Province, Early Cretaceous Jiufotang Formation.]

 

[albertonykus]

That translation is generally quite good. The main things I would change are that the phrase translated as "Jehol birds" (热河鸟类) refers specifically to Jeholornithiformes, and the diagnostic feature regarding the size of the toes actually refers to the foot claws. (Thus, Neimengornis is suggested to differ from other jeholornithiforms in that the hallux bears the largest claw on each foot.)

 

[l_raty]

Thanks Albert.
Would you concur that "模式种" is equivalent to "type species", and thus the type was fixed by original designation, not by monotypy ? (I'm more used to see "属型种" in type species designations. Google translates "模式种" as "model species".)

 

[Fred Ruhe]

I thank both Laurent and Albert for their contributions, they are very helpful and I took the liberty to use their translations in my notes!

I think the type species is fixed by monotypy as there is no remark on the type species, other then : "[Type specimen: One nearly complete fossil specimen preserved as a single plate, stored in the Inner Mongolia Natural Museum. Specimen collection number IMMNH-PV00122 (Figure 1; Table 1).]"., normally it would say under the genus desription: "type species........" and then they go on with the description of the species.

Fred

 

[l_raty]

I think the type species is fixed by monotypy as there is no remark on the type species, other then : "[Type specimen: One nearly complete fossil specimen preserved as a single plate, stored in the Inner Mongolia Natural Museum. Specimen collection number IMMNH-PV00122 (Figure 1; Table 1).]"., normally it would say under the genus desription: "type species........" and then they go on with the description of the species.

There is:

模式种: 直掌内蒙鸟 Neimengornis rectusmim sp. nov.

...where I think that "模式种: " could be seen as equivalent to "Type species: ", although Google's preferred translation is a bit different.
("直掌内蒙鸟" means something like "straight-handed Inner Mongolia bird", and is a Chinese equivalent of the name of the species.)

 

[Fred Ruhe]

...where I think that "模式种: " could be seen as equivalent to "Type species: ", although Google's preferred translation is a bit different.
("直掌内蒙鸟" means something like "straight-handed Inner Mongolia bird", and is a Chinese equivalent of the name of the species.)

Yes, that is true, it could be seen as the type fixing, 模式种 is translated as "Model species".
So I agree with you. But still I think you could also see it as just going on with the description of the new species as they do not describe the new genus, And that is how I treated it till now. Of it was bij original designation they would have described the new genus, state the type species and the go on describing the new species, but not introduce it as 模式种, but just the name of the new species, indicating it with sp. nov.

Fred

 

[l_raty]

In the Code, a type-species fixation is by original designation if there is a designation of a nominal species as the type in the OD (ICZN 68.2).
A type fixation by monotypy occurs when there is no original designation and only one taxonomic species is included in the new genus-group taxon and denoted by an available name in the OD: the nominal species denoted by the name used as valid for the species is then the type (ICZN 68.3). If there is both a designation and only one included taxonomic species, it's the designation that matters (see ICZN 68.1); the two methods give different results if the name of the designated type is treated as a synonym or used for a subspecies in the OD.

What we have here is a combined description of a new nominal genus and a single included new nominal species. In such cases, the single description is deemed to make both names available, provided that it is "marked by "gen. nov., sp. nov." or an equivalent expression" (ICZN 13.4). No such expression appears directly next to the description itself here, but the binomen is marked as "gen. et sp. nov." several times in the work (abstract, table and figure captions, conclusion), which should be sufficient, I think. (Should it not be, the genus name would be a nomen nudum.)

There is no direct relationship between the mode of type fixation and the fact that a new genus is made available by a combined genus/species description.

 

[Fred Ruhe]

内蒙鸟(新属) Neimengornis gen. nov.
模式种: 直掌内蒙鸟 Neimengornis rectusmim sp. nov.

Our differences in opinion lie in the words "combined description of a new nominal genus and a single included new nominal species."

They don'r describe the new genus, only the new species and in their systematic order the don't speak of gen. et sp. nov., but only of gen, nov. and sp. nov. and go on to describe the new species. I agree the new species must be the type, but they don't state so. So I still think it must be the type species by monotypy.

Fred

 

[l_raty]

The problem is, any new genus named after 1930 must be described (either separately, or as part of some combined description).
If you don't accept the description as a combined genus/species description, then, as you write, "they don't describe the new genus". If so, the genus name fails to satisfy ICZN 13.1.1 : it is nude, and is not available (only the species name is). A name that is not available doesn't really have a type...

 

[Fred Ruhe]

The problem is, any new genus named after 1930 must be described (either separately, or as part of some combined description).
If you don't accept the description as a combined genus/species description, then, as you write, "they don't describe the new genus". If so, the genus name fails to satisfy ICZN 13.1.1 : it is nude, and is not available (only the species name is). A name that is not available doesn't really have a type...

Well, I really don't like it but I guess you are right and I do have to except the type species is by original designation.

Fred

 

[albertonykus]

Thanks Albert.
Would you concur that "模式种" is equivalent to "type species", and thus the type was fixed by original designation, not by monotypy ? (I'm more used to see "属型种" in type species designations. Google translates "模式种" as "model species".)

Yes, "模式种" is almost certainly intended as "type species" in this context. Both "模式种" and "属型种" can be used in Chinese to mean "type species".