A new species of genus Pseudogyrinocheilus (Teleostei: Cyprinidae) from Guangxi, China

A new species, Pseudogyrinocheilus longisulcus, was discovered from a tributary of Pearl River in Jingxi Co., Guangxi, China, The new species can be distinguished from other species of Pseudogyrinocheilus by the following combination of characteristics: prolonged post-labial grooves, and extended antero-medially close to anterior end of middle lower lip, but not meeting with its counterpart; posterior margin of lower lip free; scales of abdomen from thorax to pectoral-fin base embedded under skin; lateral-line scales 40-42; dark stripe longitudinal along lateral line on flank. The key to the species of Pseudogyrinocheilus is provided.

CRANIODENTAL VARIATION OF MACAQUES ( Macaca ): SIZE,FUNCTION AND PHYLOGENY

为了研究猕猴属的颅骨差异性, 从而探 讨种间在形态、功能和系统分化方面的相互联系, 测定了11 个猕猴种类的77 个颅骨变量, 用于主成 分分析和判别分析。应用巢式分析方法, 分析过程 包括3 个步骤。所有变量根据功能和部位的不同首 先分为7 个单位: 下颌、下颌齿、上颌齿、上面 颅、下面颅、面颅后部和颅腔。第2 步根据它们所 揭示的相似性(具有相同的种间及种内差异性类 型) 合并为3 个解剖区域: 咀嚼器官(下颌、下颌 齿、上颌齿) , 面颅(上面颅和下面颅) 和整个面 颅后(面颅后和颅腔) 。第3 步从3 个解剖区域筛 选出27 个变量代表整个颅骨的形态结构。除了寻 找不同的功能单位, 解剖区域及总的颅骨具有不同 的种间和种内差异类型外, 此过程对筛出研究意义 不大的变量起很重要的作用。上述分析过程分别用 于对雌、雄性和两性的研究。所研究的11 个猕猴 种类间形成了3 聚类。第1 类包括食蟹猴(Macaca f ascicularis) 、戴帽猴( M1 sinica) 和头巾猴( M1 radiata) ; 第2 类包括猕猴( M1 mulatta ) 、熊猴 (M1 assensis ) 、平顶猴( M1 nemestrina ) 和黑猿 (M1 nigra) ; 第3 类包括蛮猴( M1 sylvanus ) 、日 本猴( M1 f uscata) 、短尾猴( M1 arctoides ) 和藏 酋猴(M1 thibetana) 。分别从两性差异、食物、生态、分类和系统分化方面进行了差异性讨论, 结果 认为猕猴种间颅骨的差异性主要是由于系统分化不 同而引起个体差异所致, 即种间和种内存在的个体 差异。在主成分分析中, 这些差异在不同的区域表 现在不同的成分上。在咀嚼器官上种间的差异在第 1 主成分上, 种内的差异则在第2 主成分上。面颅 的情况则刚好相反。这两种差异在面颅后及颅腔上 则被第1 和第2 主成分所平分。这样, 种间的差异 在咀嚼器官上大于种内的差异。种内的差异在面颅 上则大于种间的差异。这两种差异在面颅后和颅腔 上则几乎大小相等。这一研究结果表明, 与传统的 概念不同, 第2 主成分不仅仅表现形态、形状的差 异, 而如同第1 主成分一样, 也表现形态的大小成 分。此研究所揭示的猕猴种间关系部分与Foden (1976 , 1980) 和Delson (1980) 相同。如平顶猴 与黑猿、短尾猴、藏酋猴和熊猴的关系。食蟹猴、 头巾猴和戴帽猴的关系则不同, 并已得到有关分子 生物学的支持, 此3 种可能来自同一祖先并经历相 同的扩散过程。此研究所设计的巢式分析过程提供 了一种很好的差异性研究手段。最终结果暗示在形 态学研究中仅仅考虑某一区域的形态结构是很不够 的, 因为不同的部分具有不同的种间及种内差异类 型。这在化石研究中尤其要注意。

MULTIVARIATE COMPARISON OF THE FORELIMB BETWEEN STUMP-TAILED AND RHESUS MACAQUES

Rhesus macaques and stump-tailed macaques are sympatric in western Yunnan (China), coexisting or occupying habitats that show little difference. This paper tests hypotheses based on theoretical expectation from the differing biomechanical demands of terrestrial and arboreal quadrupedalism in stump-tailed macaques and rhesus macaques, respectively. Individuals of these two macaque taxa were markedly separated by the first two principal components and discriminant analyses based on 18 variables of the upper limb. The rhesus macaques appear to be more adapted for arboreal quadruped habits because of elongation of the clavicle and forearm, a larger humeral head and greater midshaft sagittal diameters of the radius and ulna.

A COMPARATIVE-STUDY OF THE ELBOW JOINTS IN 5 SPECIES OF CHINESE MACAQUES

In this paper, we report the findings of a comparative study of the elbow joints of five species of macaque that inhabit China: Macaca assamensis, M. arctoides, M. mulatta, M. thibetana and M. nemestrina. Results of multivariate analyses of size-related variables and indices of the elbow joint suggested that the breadths of the ventral aspect of the trochlea and of the medial epicondyle of the humerus as well as indices describing the head of the radius are important factors for discriminating these species. The elbow joint of M. arctoides was most similar to that of M. thibetana, no doubt reflecting recency of common ancestry and similarity in terrestrial locomotion. The structures of the elbow joints in M. nemestrina and assamensis seemed more adapted to arboreal quadrupedalism. The elbow joint of M. mulatta, however, appears intermediate between the most terrestrial and the most arboreal forms.

SCALING OF LIMB PROPORTIONS AND LIMB BONE DIAMETERS IN 3 SPECIES OF CHINESE SNUB-NOSED LANGURS (GENUS RHINOPITHECUS)

In this study, aspects of the structural mechanics of the upper and lower limbs of the three Chinese species of Rhinopithecus were examined. Linear regression and reduced major axis (RMA) analyses of natural log-transformed data were used to examine the dimensions of limb bones and other relationships to body size and locomotion. The results of this study suggest that: (1) the allometry exponents of the lengths of long limbs deviate from isometry, being moderately negative, while the shaft diameters (both sagittal and transverse) show significantly positive allometry; (2) the sagittal diameters of the tibia and ulna show extremely significantly positive allometry - the relative enlargement of the sagittal, as opposed to transverse, diameters of these bones suggests that the distal segments of the fore- and hindlimbs of Rhinopithecus experience high bending stresses during locomotion; (3) observations of Rhinopithecus species in the field indicate that all species engage in energetic leaping during arboreal locomotion. The limbs experience rapid and dramatic decelerations upon completion of a leap. We suggest that these occasional decelerations produce high bending stresses in the distal limb segments and so account for the hypertrophy of the sagittal diameters of the ulna and tibia.

CLASSIFICATION AND EVOLUTION OF ASIAN COLOBINES

In order to study the differentiation of Asian colobines, 14 variables measured on 123 skulls, including Rhinopithecus, Presbytis, Presbytiscus (Rhinopithecus avunculus), Pygathrix and Nasalis were analyzed by one-way, cluster and discriminant function analyses. Information on paleoenvironmental changes in China and southeast Asia since the late Tertiary was used to examine the influences of migratory routes and range of distribution in Asian colobines. A cladogram for 6 genera of Asian colobines was constructed from the results of various analyses. Some new points or revisions were suggested: (1) Following one of two migratory routes, ancient species of Asian colobines perhaps passed through Xizang (Tibet) along the northern bank of the Tethys sea and through the Heng Duan Shan regions of Yunnan into Vietnam. An ancient landmass linking Yunnan and Xizang was already present on the east bank of the Tethys sea. Accordingly, Asian colobines would have two centers of evolutionary origin: Sundaland and the Heng Duan Shan regions of China. (2) Pygathrix shares more cranial features with Presbytiscus than with Rhinopithecus. This differs somewhat from the conclusion reached by Groves. (3) Nasalis (karyotype: 2n = 48) may be the most primitive genus among Asian colobines. Certain features shared with Rhinopithecus, e.g. large body size, terrestrial activity and limb proportions, can be interpreted as symple-siomorphic characters. (4) Rhinopithecus, with respect to craniofacial features, is a special case among Asian colobines. It combines a high degree of evolutionary specialization with retention of some primitive features thought to have been present in the ancestral Asian colobine.

MANDIBULAR MORPHOMETRICS AMONG MACAQUES - THE CASE OF MACACCA-THIBETANA

Recent field studies suggest that Macaca thibetana, a large endemic Chinese macaque, may be quite folivorous, distinguishing it from most other macaque species, which tend to be primarily frugivorous. To understand how this diet affects its masticatory system, we conducted a comparative morphometric study of mandibular dimensions. We took linear measurements from male and female mandibles of this species as well as four other macaques-M. fascicularis, M. nemestrina, M. arctoides, and M. assamensis-and four species of Presbytis-P. obscura, P. rubicunda, P. cristata, and P. phayrei-and subjected to them to a variety of analyses. Based on analyses of variances and discriminant analyses on each sex individually, the mandible of M. thibetana corresponds to expected patterns for folivorous primates with respect to its wide condyles and thick corpora: However, the height of the corpus and symphysis are lower, and the anteroposterior length of the condyle is longer than predicted for a folivore. In addition to interpretations specifically relating to M. thibetana, we also discuss the functional morphology of the other species in light of what is published about their diets.

COMPARISON OF MASTICATORY MORPHOLOGY BETWEEN RHINOPITHECUS-BIETI AND R-ROXELLANA

The masticatory apparatus for two endemic species of golden monkey in China, Rhinopithecus bieti and Rhinopithecus roxellana, were compared with those of macaques, Macaca and leaf monkeys, Presbytis. Multivariate analyses demonstrated that the two golden monkey species are distinct. Interspecies allometric analyses revealed that golden monkeys differ in their masticatory apparatus from both macaques and leaf monkeys. The prominent symphysial fusion, corpus, and sagittal condylar dimension of R. roxellana may produce efficient biting force on the incisal and posterior canine teeth, with the heavy reaction force barn on the temporomandibular joint. However, the well-developed bizygamatic width and mandibular height in R. bieti suggest that posterior canine function is similarly prominent in R. roxellana, while incisal function is not. (C) 1995 Wiley-Liss, Inc.

Morphometric analysis of Macaca arctoides and M-thibetana in relation to other macaque species

As a first step in reviewing the classification of the two stump-tailed macaque species, Macaca arctoides and M. thibetana, as compared with other species of the genus Macaca, 72 linear dental and cranial variables of 11 macaque species were examined by morphometric analyses. The results indicate that the two stump-tailed species are the largest of the macaques and although rather similar overall, they exhibit significant differences in the pattern of variation in most of the five skull regions as shown by Principal Components and Canonical Variate Analyses. Euclidean Distances based on Canonical Variate scores indicate that the females of M. arctoides and M. thibetana are more widely separated than eight other pairs of macaque species, and that the separations of the respective males are greater than those of three other pairs of species. These findings are consistent with FOODEN's classification of the stump-tailed macaques as two separate species (FOODEN, 1976; FOODEN et al., 1985). The present results suggest, as other researchers have proposed on the basis of external features, biochemistry and genetics, that the two stump-tailed macaque species and M. assamensis are closely related. The results also tentatively imply associations with M. fuscata and M. sylvanus but these require further study. The findings have implications for the assessment of the various Chinese Pleistocene macaque fossils.