AN UNUSUAL FOSSIL FRUCTIFICATION FROM THE JURASSIC OF OAXACA,MEXICO

A fructification with unusual branching arrangement, Perezlaria oaxacensis gen. et sp. nov., is described from the Middle Jurassic Zorrillo Formation of Oaxaca, Mexico. The sporangial heads are similar to the pollen-bearing organs of several Mesozoic pteridosperms. The association of P. oaxacensis, as well as some isolated organs resembling the synangia of Caytonanthus, with glossopteroid foliage is noted.     

Sunosuchus (Archosauria, Crocodyliformes) from the Toutunhe Formation (Middle Jurassic) of the Southern Junggar Basin (Xinjiang, NW-China)

A new specimen of the widespread Middle Jurassic to Lower Cretaceous Asian gonipholidid crocodilian genus Sunosuchus is described on the basis of a partial skeleton from the Upper Toutunhe Formation (Middle Jurassic, ?Bathonian-Callovian) of Liuhonggou, SW of Urumqi, Xinjiang Uygur Autonomous Region, People’s Republic of China. The specimen is represented by a partial mandible, teeth, vertebrae, limb and girdle bones and osteoderms. It can be distinguished from other nominal species of the genus by a unique combination of characters: slightly heterodontous dentition, strongly sculptured posteroventral part of the mandible, short fenestra mandibularis, convex dorsal surface of the retroarticular process, keeled cervical vertebral centra and ventral osteoderms with a distinctive sculpture of wide pits and narrow ridges. The heterodontous dentition is a potential autapomorphy of this form. The new specimen is closest in morphology to material described recently from the Callovian of Kirghisia as Sunosuchus sp. It represents the second Middle Jurassic record of the genus, the first crocodile from the Toutunhe Formation, the first substantial crocodile find from the Mesozoic of the Southern Junggar Basin, and the first Middle Jurassic record of Sunosuchus from China. This extends both the paleobiogeographical distribution of the genus in Asia and its stratigraphic distribution in China considerably.     

Two new species of Paramesosciophilodes (Diptera,Nematocera, Mesosciophilidae) from the Middle Jurassic of China

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.     

Investigations of North American cycadeoids: Williamsonian cones from the Jurassic of Oaxaca,Mexico

A study of williamsonian cones from Middle Jurassic rocks of Oaxaca, Mexico, indicates that Weltrichia mexicana (Wieland) Harris (formerly Williamsonia mexicana) is probably not a fructification. Ovulate cones recognized from localities near Tezoatlán are Williamsonia netzahualcoyotlii Wieland, W. oaxacensis sp. nov., W. huitzilopochtlii Wieland, and W. diquyui sp. nov. Notable is the similarity among williamsonian cones in Jurassic rocks of such widely separated places as Oaxaca, Mexico, Yorkshire, England, and Rajmahal Hills, India. The mode of preservation of williamsonian cones suggest a growth habit involving slender, branched stems with exposed cones that abscised from the plants on which they were borne. Conceivably, further development, including fertilization, could have occurred after the cones were dropped.     

The first euthemistid damsel-dragonfly?from the Middle Jurassic of China (Odonata,Epiproctophora,?Isophlebioptera)

Sinoeuthemis daohugouensis gen. et sp. n. is the first record of the isophlebiopteran family Euthemistidae from Middle Jurassic of northeast China, while previously this family was restricted to the early Late Jurassic Kazakhstan. This new finding allows us to emend the family diagnosis with hindwing characters. This new species shows a mixture of characters alternatively present in different genera of the two families Euthemistidae and Sphenophlebiidae.     

Biodiversity of sweetpotato (iPomoea batatas,Convolvulaceae) in Southern Mexico

Between 1987 and 1992 the phytogeographic region of southern Mexico was explored during three collecting trips made in search of cultivated and wild germplasm of the sweetpotato (Ipomoea batatas). The first trip was made in 1987, when we collected wild species in Ipomoea section Batatas found in the southeastern and southwestern regions of Mexico. A second trip was made in 1990, when we collected accessions of the cultivated species as well as wild species in the southeast, southwest and northeast. The third and final trip was oriented at identification, characterization and collecting seeds in the ecological niches ofI.tabascana andI.umbraticola. As a result of the three trips we collected 165 accessions of cultivated and wild germplasm with populations dispersed in 147 localities in 15 states of the Mexican region: Veracruz, Tabasco, Campeche, Chiapas, Oaxaca, Yucatán, Guerrero, Michoacán, San Luis Potosí, Hidalgo, Querétaro, Tamaulipas, Guanajuato, Puebla and México. Of the total accessions some 64 (38.3%) were of the cultivated species including nine accessions of feral material, and 103 accessions (61.7%) were of wild species made up of 59 accessions of seven species in the section Batatas, 37 of other species in the family Convolvulaceae, and seven yet to be determined. We have identified the largest genetic biodiversity in six localities of five states: Tabasco, Oaxaca, Michoacán, San Luis Potosí, and Puebla. Biodiversity maintenance in this region is associated with the day-of-the-dead festivities.     

Two new species of Trichoceridae from the Middle Jurassic Jiulongshan Formation of Inner Mongolia,China

Two new species, Eotrichocera (Archaeotrichocera) longensis sp. n. and Eotrichocera (Archaeotrichocera) amabilis sp. n. of Trichoceridae are described based on a combination of the following characters: Sc ending proximad of the forking of R₂, shape of d cell and A₂ rather short and bending sharply toward posterior margin. These fossil specimens were collected from the Middle Jurassic Jiulongshan Formation of Daohugou in Inner Mongolia, China.     

本内苏铁类雄性生殖器官Weltrichia属一新种

报道了本内苏铁类雄性生殖器官Weltrichia属的一个新种--Weltrichia daohugouensis sp.nov.,标本发现于内蒙古宁城山头乡道虎沟村附近的中侏罗统海房沟组.它是一个分离保存的本内苏铁类单性雄球花(球穗花序),在侧向压缩的平面上展开,呈扇形.基部球花梗未保存,下部由11个窄楔形的裂片融合成漏斗状或杯状,上部裂开成数目相等的游离的小孢子叶.每个小孢子叶的上部有两列花粉囊.文中对新种进行了详细地描述和讨论.并对W.huangbanjigouensis Su et Zheng的鉴定特征进行了修订.     

Merychippus (Mammalia, Perissodactyla, Equidae) from the Middle Miocene of state of Oaxaca, southeastern Mexico

Mexican material referable to Merychippus from two localities in eastern Oaxaca was described first nearly 50 years ago. Subsequent work there and in Central Oaxaca, spanning some 30 years, has allowed to establish the detail stratigraphy in both regions, and assembled a collection of merychippine material from the Matatlán (Central Oaxaca) and El Camarón (eastern Oaxaca) Formations, both K-Ar dated ~15 Ma (late early Barstovian). Detailed taxonomic analysis of this collection indicate the presence of two subhypsodont horse species referable to “Merychippus” cf. “M.” primus and “M.” cf. “M.” sejunctus in both regions. These records document the coexistence in tropical southern North America of basal and hipparionine affinity merychippine grade species, and provide a glimpse in to the diversity of subhypsodont equids in this region.     

New Phoenicopsis leaves (Czekanowskiales) from the Middle Jurassic Daohugou Biota,China and their roles in phytogeographic and paleoclimatic reconstruction

The Middle Jurassic Jiulongshan Formation, distributed in the Daohugou area, Ningcheng County, Inner Mongolia, China, is famous for yielding abundant, well-preserved fossil vertebrates and invertebrates. However, only a few fossil plants have been reported to date. In this paper, one new species of Czekanowskiales, Phoenicopsis (Windwardia) daohugouensis n. sp. is described based upon leaf morphology and epidermal characters. The new species represents the first record of Czekanowskiales from the Daohugou Biota. The discovery of the new species reveals the significance of the Daohugou flora as one of the deciduous forests in the temperate-warm temperate zone of Eurasia during the Middle Jurassic.     

The earliest fossil record of Panorpidae (Mecoptera) from the Middle Jurassic of China

The early history of Panorpidae (Mecoptera) is poorly known due to sparse fossil records. Up to date, only nine fossil species have been described, all from the Paleogene, except the Early Cretaceous Solusipanorpa gibbidorsa Lin, 1980. However, we suggest S. gibbidorsa is too incompletely preserved to permit even family classification. A new genus with two new species, Jurassipanorpa impunctata gen. et sp. n. and Jurassipanorpa sticta sp. n., are described based on four well-preserved specimens from the late Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. These two new species are the earliest fossil records of Panorpidae. The new genus is erected based on a combination of forewing characters: both R₁ and Rs₁ with two branches, 1A reaching posterior margin of wing distad of the forking of Rs from R_1, and no crossveins or only one crossvein between veins of 1A and 2A. In all four specimens, long and robust setae ranging from 0.09 to 0.38 mm in length and pointing anteriorly, are present on anal veins of forewings. The function of these setae is enigmatic.     

Two new species of Archaeohelorus (Hymenoptera,Proctotrupoidea, Heloridae) from the Middle Jurassic of China

Two new fossil species, Archaeohelorus polyneurus sp. n. and A. tensus sp. n., assigned to the genus Archaeohelorus Shih, Feng & Ren, 2011 of Heloridae (Hymenoptera), are reported from the late Middle Jurassic, Jiulongshan Formation of Inner Mongolia, China. Based on the well-preserved forewings and hind wings of these specimens, the diagnosis of the Archaeohelorus is emended: forewing 2cu-a intersecting Cu and Rs+M at the same point or postfurcal, and hind wing may have tubular veins C, Sc+R, R, Rs, M+Cu, M and Cu distinct, or simplified venation. The new findings also elucidate the evolutionary trend of forewing and hind wing venation and body size for the Heloridae from the late Middle Jurassic to now.     

Two new species of <Emphasis Type="Italic">Arachnothryx</Emphasis> (Rubiaceae) from Oaxaca,Mexico

Two new species of Arachnothryx (Guettardeae, Rubiaceae) from the cloud forest of the Sierra Norte of Oaxaca, Mexico are described and illustrated. Arachnothryx axillaris together with A. heteranthera are the only two species in the genus with axillary inflorescences, but otherwise they are not similar. The new species is more similar to A. capitellata, but it differs in pubescence and inflorescence morphology. Arachnothryx flores-olverae can be confused with A. buddleioides mainly because they share discolorous leaves with densely tomentose pubescence, but they differ in stipule and inflorescence morphology. With these two new species the Sierra Norte of Oaxaca becomes more evidently the main hotspot of species diversity for the genus.     

Polystichum lilianae sp. nov. (Dryopteridaceae) and its relationships to P. fournieri and P. turrialbae

Morphological, isozyme, and cytological analyses of the small, pale-scaled polystichums from oakdominated montane rain forests in Costa Rica and Mexico reveal the presence of a separable undescribed species endemic to the Cordillera de Talamanca of Costa Rica. The new taxon,Polystichum lilianae, is an allotetraploid hypothesized to have the sympatricP. turrialbae as one diploid progenitor based on isozyme characters. The isozyme and morphometric data also support the inclusion ofP. smithii, described from southern Mexico, inP. turrialbae, described from Costa Rica. The namePolystichum fournieri, formerly used for all of these plants, applies to species endemic to Oaxaca and Chiapas, Mexico. It is not a progenitor ofP. lilianae.     

Les Cervidae (Mammalia, Artiodactyla) du Pléistocène supérieur-Holocène ancien de la région du Parc National Serra da Capivara (Piauí, Brésil)

The Upper Pleistocene/Lower Holocene fossil-bearing sites of the Serra da Capivara National Park Region have yielded three cervid species: Mazama gouazoubira, M. americana and Blastocerus dichotomus, all currently living in South America, the two first in the region. A grand total of more than one hundred remains demonstrates the presence of Mazama gouazoubira in seven sites, mainly the Toca das Moendas, the Toca do Serrote do Artur, the Toca da Cima dos Pilão. This small species shows, since the Upper Pleistocene, a conspicuous tendency to reduce the average dimensions of its teeth and long bones. From the taller M. americana, only a dozen of remains were found in four sites, mainly the Sitio do Meio. In all of these it is sympatric with M. gouazoubira. It differs from this last one by its cheek teeth and its limb bones size and proportions. The oldest site where the species is known is Tarija (Bolivia, Middle Pleistocene) and it does not show any significant changes in size and proportions between recent and fossil samples. Sixteen remains of the large B. dichotomus were found in five sites, mainly the Toca das Moendas and the Toca da Barra do Antonião. The species is a rare fossil, but is frequently figured in the rock art painting of the region, where it is presently unknown.     

New Mexican species of Byttneria (Sterculiaceae), Bakeridesia (Malvaceae), and Triumfetta (Tiliaceae)

Recent collections have brought to light the following new species from the states of Tabasco and Oaxaca, Mexico:Byttneria fluvialis (Sterculiaceae) from Tabasco;Bakeridesia amoena (Malvaceae), andTriumfetta calzadae (Tiliaceae) from Oaxaca.     

Four new species of Cymatodera Gray from Mexico (Coleoptera,Cleridae, Tillinae)

Four new species of Cymatodera from Mexico: Cymatodera bogcioides sp. n.; Cymatodera pueblae sp. n.; Cymatodera mitae sp. n.; and Cymatodera lineata sp. n. are described based on adult male and female specimens. Male genitalia and other characters of taxonomic value are presented.     

A remarkable new genus of Procercopidae (Hemiptera: Cercopoidea) from the Middle Jurassic of China

Jurocercopis grandis, a new genus and species belonging to Procercopidae (Hemiptera: Cercopoidea), is described, based on seven specimens from the Middle Jurassic of Daohugou, China. It differs distinctly from other genera as follows: body and wings obviously large; pronotum with posterior margin straight; tegmen with costal margin convex at about basal 0.4 wing length; hind basitarsomere with a row of apical small teeth.