Astragalar morphology of Afradapis, a large adapiform primate from the earliest late Eocene of Egypt

The ～37 million-year-old Birket Qarun Locality 2 (BQ-2), in the Birket Qarun Formation of Egypt's Fayum Depression, yields evidence for a diverse primate fauna, including the earliest known lorisiforms, parapithecoid anthropoids, and Afradapis longicristatus, a large folivorous adapiform. Phylogenetic analysis has placed Afradapis as a stem strepsirrhine within a clade of caenopithecine adapiforms, contradicting the recently popularized alternative hypothesis aligning adapiforms with haplorhines or anthropoids. We describe an astragalus from BQ-2 (DPC 21445C), attributable to Afradapis on the basis of size and relative abundance. The astragalus is remarkably similar to those of extant lorises, having a low body, no posterior shelf, a broad head and neck. It is like extant strepsirrhines more generally, in having a fibular facet that slopes gently away from the lateral tibial facet, and in having a groove for the tendon of flexor fibularis that is lateral to the tibial facet. Comparisons to a sample of euarchontan astragali show the new fossil to be most similar to those of adapines and lorisids. The astragali of other adapiforms are most similar to those of lemurs, but distinctly different from those of all anthropoids. Our measurements show that in extant strepsirrhines and adapiforms the fibular facet slopes away from the lateral tibial facet at a gradual angle (112-126°), in contrast to the anthropoid fibular facet, which forms a sharper angle (87-101°). Phylogenetic analyses incorporating new information from the astragalus continue to support strepsirrhine affinities for adapiforms under varying models of character evolution.     

New primate first metatarsals from the Paleogene of Egypt and the origin of the anthropoid big toe

The specialized grasping feet of primates, and in particular the nature of the hallucal grasping capabilities of living strepsirrhines and tarsiers (i.e., ‘prosimians’), have played central roles in the study of primate origins. Prior comparative studies of first metatarsal (Mt1) morphology have documented specialized characters in living prosimians that are indicative of a more abducted hallux, which in turn is often inferred to be related to an increased ability for powerful grasping. These include a well-developed peroneal process and a greater angle of the proximal articular surface relative to the long axis of the diaphysis. Although known Mt1s of fossil prosimians share these characters with living non-anthropoid primates, Mt1 morphology in the earliest crown group anthropoids is not well known. Here we describe two Mt1s from the Fayum Depression of Egypt - one from the latest Eocene (from the ∼34 Ma Quarry L-41), and one from the later early Oligocene (from the ∼29-30 Ma Quarry M) - and compare them with a sample of extant and fossil primate Mt1s. Multivariate analyses of Mt1 shape variables indicate that the Fayum specimens are most similar to those of crown group anthropoids, and likely belong to the stem catarrhines Catopithecus and Aegyptopithecus specifically, based on analyses of size. Also, phylogenetic analyses with 16 newly defined Mt1 characters support the hypotheses that “prosimian”-like Mt1 features evolved along the primate stem lineage, while crown anthropoid Mt1 morphology and function is derived among primates, and likely differed from that of basal stem anthropoids. The derived loss of powerful hallucal grasping as reflected in the Mt1 morphology of crown anthropoids may reflect long-term selection for improved navigation of large-diameter, more horizontal branches at the expense of movement in smaller, more variably inclined branches in the arboreal environment.     

A new Late Eocene primate from the Krabi Basin (Thailand) and the diversity of Palaeogene anthropoids in southeast Asia

According to the most recent discoveries from the Middle Eocene of Myanmar and China, anthropoid primates originated in Asia rather than in Africa, as was previously considered. But the Asian Palaeogene anthropoid community remains poorly known and inadequately sampled, being represented only from China, Myanmar, Pakistan and Thailand. Asian Eocene anthropoids can be divided into two distinct groups, the stem group eosimiiforms and the possible crown group amphipithecids, but the phylogenetic relationships between these two groups are not well understood. Therefore, it is critical to understand their evolutionary history and relationships by finding additional fossil taxa. Here, we describe a new small-sized fossil anthropoid primate from the Late Eocene Krabi locality in Thailand, Krabia minuta, which shares several derived characters with the amphipithecids. It displays several unique dental characters, such as extreme bunodonty and reduced trigon surface area, that have never been observed in other Eocene Asian anthropoids. These features indicate that morphological adaptations were more diversified among amphipithecids than was previously expected, and raises the problem of the phylogenetic relations between the crown anthropoids and their stem group eosimiiforms, on one side, and the modern anthropoids, on the other side.     

Enigmatic new mammals from the late Eocene of Egypt

A new mammalian genus and species from the earliest late Eocene of Egypt is represented by a lower jaw fragment and two isolated lower molars. A rare combination of features and the fragmentary nature of the materials make their taxonomic assignment to either Marsupialia or Chiroptera uncertain. The holotype of the new genus is the best-preserved specimen in the sample, a dentary fragment with two molars that have uncompressed trigonids, weak buccal cingulids, and a nyctalodont arrangement of the hypocristid. Some traits appear to more clearly support marsupial, as opposed to chiropteran, affinities for this species, including the very likely presence of four molars in the dentary. The enamel of an additional lower molar assigned to this species consists of a single layer of radial enamel without any prism decussation, an enamel type that characterizes marsupials as well as chiropterans. A second taxon is represented by two isolated upper molars. Some traits appear to more clearly support marsupial, as opposed to chiropteran, affinities for these species, including the orientation of pre- and postprotocristae, the moderately slender lingual portion of the trigon, and the absence of any talon expansion. As some of these features can be found in various bat clades, chiropteran affinities for these species cannot be ruled out, but we propose that the new taxa are more likely to represent specialized ‘didelphimorphian’ marsupials.      

Hindlimb of a giant terrestrial bird from the upper Eocene, Fayum, Egypt

Eremopezus eocaenus Andrews, 1904 is a giant groundbird from upper Eocene deposits of the Fayum, Egypt, which has hitherto been known from non-diagnostic fragmentary material. New fossils collected from quarry L-41 of the Jebel Qatrani Formation include two well-preserved distal tarsometatarsi and an associated whole tarsometatarsus and distal tibiotarsus that allow a more precise evaluation of the phylogenetic position and tarsal function of Eremopezus. Unlike most ratites, the distal tarsometatarsus has a patent distal foramen and a slight hallucal digit. The trochlea for digits II and IV are only slightly reduced in size, are splayed to the right, and the heads lack deep grooving. These features resemble the condition seen in BalaenicepsSagittarius, suggesting active use of the toes in grasping or manipulation, rather than the condition in graviports and cursors, which have reduced medial and lateral trochleae often with distinct grooving of the heads. The limb is relatively long and gracile, another difference from graviports. There is no compelling evidence to link Eremopezus to any known ratite lineage, to the Phorusrhacoidea, or to the extinct predatory birds of the Eocene (e.g. Diatryma, Gastornis). We suggest that Eremopezus represents an endemic African group that independently attained large size and flightlessness.     

New adapiform primate fossils from the late Eocene of Egypt

Abstract

Caenopithecine adapiform primates are currently represented by two genera from the late Eocene of Egypt (Afradapis and Aframonius) and one from the middle Eocene of Switzerland (Caenopithecus). All are somewhat anthropoid-like in several aspects of their dental and gnathic morphology, and are inferred to have been highly folivorous. Here we describe a new caenopithecine genus and species, Masradapis tahai, from the ~37 million-year-old Locality BQ-2 in Egypt, that is represented by mandibular and maxillary fragments and isolated teeth. Masradapis is approximately the same size as Aframonius but differs in having a more dramatic distal increase in molar size, more complex upper molar shearing crests, and an exceptionally deep mandibular corpus. We also describe additional mandibles and part of the orbit and rostrum of Aframonius which suggest that it was probably diurnal. Phylogenetic analyses place Masradapis either as the sister taxon of Aframonius (parsimony), or as the sister taxon of Afradapis and Caenopithecus (Bayesian methods). Bayesian tip-dating analysis, when combined with Bayesian biogeographic analysis, suggests that a common ancestor of known caenopithecines dispersed to Afro-Arabia from Europe between 49.4 and 47.4 Ma, and that a trans-Tethyan back-dispersal explains Caenopithecus’ later presence in Europe.

For Masradapis: https://www.zoobank.org/urn:lsid:zoobank.org:act:41BC8459-7CCE-487F-BC59-1C34257D5C4E

For Masradapis tahai: https://www.zoobank.org/urn:lsid:zoobank.org:act:C0A620AD-6FCA-4649-A980-FCA237AFE39D     

A highly derived anomalurid rodent (Mammalia) from the earliest Late Eocene of Egypt

Abstract: A new genus and species of diminutive anomalurid rodent, Shazurus minutus, is described on the basis of 15 isolated teeth from the earliest late Eocene (approximately 37 Ma) Birket Qarun Locality 2 in the Fayum Depression of northern Egypt. Shazurus is surprisingly specialized for its age, being most similar in dental morphology to early Miocene Paranomalurus and extant Anomalurus, and is quite different from the roughly contemporaneous anomaluroid genera Nementchamys and Pondaungimys from Algeria and Myanmar, respectively. Parsimony analysis of dental features places Shazurus within crown Anomaluridae as a sister group of two species of Paranomalurus to the exclusion of extant Anomalurus and Idiurus. The marked morphological differences between the two oldest Afro‐Arabian anomaluroids (Shazurus and Nementchamys) suggest that the taxa share a much more ancient common Afro‐Arabian ancestor, possibly derived from Zegdoumyidae. Isolated teeth of Shazurus and other Eocene anomaluroids reveal little about their palaeobiology, but the complete absence of Anomaluroidea from the younger (late Eocene to early Oligocene) Jebel Qatrani Formation is presumably a reflection of environmental change through the late Eocene in northern Africa.     

Paleobiology of the oligopithecines,the earliest known anthropoid primates

Anthropoid primates of the subfamily Oligopithecinae are late Eocene in age, and have a known distribution of Northeast Africa and the Arabian Peninsula. Body sizes of the three known oligopithecine species are estimated from allometric molar size regressions to be 700–1000 g forOligopithecus savagei, 600–900 g forCatopithecus browni, and 500 g for the least well-known and smallest species,Proteopithecus sylviae. Occlusal features of the molar teeth, considered in conjunction with body size, suggest that all three species were frugivorous and insectivorous. The orbital size ofCatopithecus indicates a diurnal activity cycle. A relatively broad interobital region in this species may indicate prosimian-like or callitrichid-like olfactory adaptations. Structural features of the crushed skull suggest thatCatopithecus had a smaller cranial capacity than those of extant anthropoids with a similar body size. Fossil plants and birds from localities yielding oligopithecines suggest a wet, warm, tropical, forested, swampy environment. These paleobiological inferences about the extinct oligopithecines are discussed in relation to questions about primate adaptations near the prosimian-anthropoid transition.     

The paleobiology of Amphipithecidae, South Asian late Eocene primates

Analysis of the teeth, orbital, and gnathic regions of the skull, and fragmentary postcranial bones provides evidence for reconstructing a behavioral profile of Amphipithecidae: Pondaungia, Amphipithecus, Myanmarpithecus (late middle Eocene, Myanmar) and Siamopithecus (late Eocene, Thailand). At 5-8 kg, Pondaungia, Amphipithecus, and Siamopithecus are perhaps the largest known Eocene primates. The dental and mandibular anatomy suggest that large-bodied amphipithecids were hard-object feeders. The shape of the mandibular corpus and stiffened symphysis suggest an ability to resist large internal loads during chewing and to recruit significant amounts of muscle forces from both the chewing and non-chewing sides of the jaw so as to increase bite force during mastication. The large spatulate upper central incisor of Pondaungia and projecting robust canines of all the larger amphipithecids suggest that incisal food preparation was important. The molars of Siamopithecus, Amphipithecus, and Pondaungia have weak shearing crests. This, and the thick molar enamel found in Pondaungia, suggests a diet of seeds and other hard objects low in fiber. In contrast, Myanmarpithecus was smaller, about 1-2 kg; its cheek teeth suggest a frugivorous diet and do not imply seed eating. Postcranial bones (humerus, ulna, and calcaneus) of a single large amphipithecid individual from Myanmar suggest an arboreal quadrupedal locomotor style like that of howler monkeys or lorises. The humeral head is rounded, proximally oriented, and the tuberosities are low indicating an extremely mobile glenohumeral joint. The great thickness of the midshaft cortical bone of the humerus implies enhanced ability to resist bending and torsion, as seen among slow moving primate quadrupeds. The elbow joint exhibits articular features for enhanced stability in habitually flexed positions, features also commonly found in slow moving arboreal quadrupeds. The short distal load arm of the calcaneus is consistent with, but not exclusive to, slow, arboreal quadrupedalism, and suggests no reliance on habitual leaping.     

Evolutionary relationships of a new genus and three new species of Omomyid primates (Willwood Formation, Lower Eocene, Bighorn Basin, Wyoming)

Studies of new finds of omomyid primates from the lower Eocene Willwood Formation of northwest Wyoming reveal the presence of a new genus and two new species of anaptomorphines and a new species of omomyine. All were apparently short-lived immigrants into the Bighorn Basin. The new genus and speciesTatmanius szalayi is typified by a diminutive single-rooted p3 and a bilobed-rooted p4 with a crown smaller than ml. These traits were probably derived fromPseudotetonius and parallel similar conditions inTrogolemur andNannopithex. The new speciesArapahovius advena is the first occurrence ofArapahovius outside the Washakie Basin, where it appears to have also been a vagrant species.Steinius annectens, sp. nov., is larger than the olderSteinius vespertinus and strengthens the alliance between this genus and BridgerianOmomys carteri, although which species ofSteinius is closer toOmomys is not yet clear. The available evidence suggests a derivation ofOmomys (Omomyini) fromSteinius and all Washakiini from the anaptomorphineTeilhardina, which would indicate that Omomyinae were at least diphyletic. Preliminary evidence suggests that the geographic distributions of at least some Willwood omomyids correlate with paleosol distributions.     

中国五种仙茅科植物叶形态及其分类学意义

为澄清仙茅科属间界限不清的分类学问题,该文以中国仙茅科3属5种植物为研究对象,利用显微镜、扫描电镜和石蜡切片技术,观察了其叶形态、叶表皮显微特征和叶解剖特征。结果表明:(1)叶形态有小型平整叶、中型波状叶、大型折扇状叶三种。(2)叶表皮毛状体结构为单细胞单列,可分为长柔毛、糙伏毛和星状柔毛三类。(3)叶表皮细胞有六边形和五边形,气孔为平列型和椭圆形,气孔大小和气扎密度呈反比。(4)叶表皮蜡质纹饰有光滑、颗粒、屑状和壳状四类。(5)叶中脉横切面分为平整型和龙骨型,维管束有圆形和椭圆形,叶表皮厚度与表皮细胞具有正相关性。对5种植物的叶形态和叶解剖特征比较分析认为,一些特征组合有助于理解仙茅科属间的亲缘关系和物种鉴定,支持大叶仙茅属独立于仙茅属。     

亮花芒毛苣苔在中国的发现及近缘种花粉形态研究

该文报道了中国苦苣苔科(Gesneriaceae)植物分布新记录种,即亮花芒毛苣苔(Aeschynanthus fulgens Wall. exR. Br.),同时描述了该新记录种的分类学特征,并提供了该新记录种的引证标本和图片。此外,还比较了该新记录种与束花芒毛苣苔(A. hookeri C. B. Clarke)的花粉形态特征,发现二者花粉形态及纹饰存在显著差异。凭证标本保存在河南农业大学植物标本馆(HEAC)中。     

Austrini - a new tribe of Tropiduchidae planthoppers from the Eocene Baltic amber (Hemiptera: Fulgoromorpha)

A new tribe Austrini n. trib. of Tropiduchidae planthoppers from the Eocene Baltic amber is described to comprise Austris raffelis n. gen., n. sp. Fossils ascribed to family Tropiduchidae are discussed.     

The taxonomic status ofpraeanthropus africanus (primates: Pongidae) from the late pliocene of Eastern Africa

The taxonPraeanthropus africanus (Weinert, 1950), represented by the Garusi maxilla, is valid and reinstated. The morphological pattern of the Garusi maxilla is not that of a primitive hominid, but of a relatively generalized pongid. Since the apelike lectotype L.H.-4 and paralectotype A.L.200-1a ofAustralopithecus afarensis Johanson et al. 1978 are conspecific withP. africanus, and originate from the same formation, they are reassigned toPraeanthropus africanus.     

A new genus and species of an early Eocene primate from North Africa

A new Adapiform Primate from the locality of Chambi (Tunisia) is described and assigned toDjebelemur martinezi gen.nov., sp. nov. Holotype CBI 33, fragment of left mandible with P/3-M/3. Other material includes a lower and two upper isolated molars and one probable lower canine. This new material is assigned to the Adapidae.     

New primates from the late Eocene of Thailand: a contribution to primate diversity in the Paleogene of Asia

We report the discovery of two new primates from the late Eocene Krabi Basin, southern Thailand. One isolated upper molar displays morphological features (protocone united with hypocone by the prehypocrista, postprotocrista extended distobuccally) suggesting possible phylogenetic relationships with Amphipithecidae, while an isolated lower molar is tentatively referred to as a new tarsiiform, mainly on the basis of its paraconid and entoconid morphology. Although very scarce, these remains expand the record of Paleogene primates in Southeast Asia, and testify to their successful radiation in that area.     

凤仙花属棒凤仙亚属(凤仙花科)植物花粉形态的分类学意义

棒凤仙亚属代表着凤仙花属最先分化出的一支,以多年生草本,多于5朵花的总状花序,侧生萼片4枚,3沟花粉,心皮四室且每室具1枚种子,果实棒锤状,种子椭圆形以及三沟花粉其极面观为三角形而区别于其它种类。该亚属主要分布于中国南部,少数种类辐射分布至华中和中南半岛地区。已有报道证实花粉的形态特征对凤仙花属植物的属下分类具有重要意义,但对棒凤仙亚属的种类少有涉及。为了进一步探讨该亚属花粉的形态特征及其分类学价值,该研究应用扫描电镜技术对国产棒凤仙亚属植物的14种以及凤仙花亚属的窄萼凤仙花的花粉进行了观察。结果表明：棒凤仙亚属的花粉以单粒存在,具3条萌发沟,辐射对称,极面观为三角形或三角状圆形,花粉粒外壁具均匀的网状纹饰,网脊平滑或具波状边缘,网眼中具不同密度的颗粒状突起。棒凤仙亚属的花粉形态与水角属的花粉形态相似,表现出了其原始性;其花粉形态特征与花部形态性状等相关性差,对该亚属的组级分类意义较小,但对于该亚属的种间界定具有重要意义;而其花粉的极面观形状、赤道面观形状以及网状纹饰等变异相对稳定,对于界定该亚属具有重要的分类学价值。     

The first New World occurrence of the Eocene birdPlesiocathartes (Aves: ?Leptosomidae)

Two new species of the Eocene avian taxonPlesiocathartes (Aves: ?Leptosomidae) are described. They are similar in size and overall appearance to other members of the genus, as well as to the extant Madagascan cuckoo-rollerLeptosomus discolor. So far, putative fossil Leptosomidae have been found only in the Eocene European de-posits of Messel, Geiseltal, Quercy, and London Clay. Both new species are from the Lower Eocene Green River Formation (USA) and thus the first New World representatives of this taxon.     

中国膨果豆属(豆科)一新组合

原簇毛黄耆亚属的部分种类从黄耆属中分出,在此基础上恢复了膨果豆属,由此也产生了许多新组合。其中,新组合蒺藜叶膨果豆包含了原蒺藜叶黄耆和甘青黄耆。为验证该分类处理的合理性,该文统计分析了蒺藜叶黄耆和甘青黄耆在果实形态上的差异,同时比较了二者的地理分布式样。结果表明:甘青黄耆和蒺藜叶黄耆之间存在着明显区别,甘青黄耆种级的分类学地位应予以保留,新组合为甘青膨果豆[Phyllolobium tangutica(Batalin)Y.Kang M.L.Zhang]。