The motoneurons, dorsal root ganglion (DRG) and sympathetic ganglion (SG) cells forming the common peroneal (CPN) and tibial (TN) nerves of young and semiadult monkeys (Macaca fascicularis) were localised by the horseradish peroxidase method of tracing neuronal connections. The motoneurons forming the CPN occur in the L4-L6 segments, appearing as 1-3 groups and occupying the retroposterolateral (rpl), posterolateral (pl) and central (c) groups of motor nuclei. The motoneurons forming the TN occur in the L4-L7 segments, appearing as 1-4 groups and occupying the rpl, pl, c and anterolateral (al) groups. The motoneurons and DRG cells forming the CPN show peak frequencies at the L5 level, and the SG cells forming the same nerve, at the L6 level in most cases. The motoneurons and DRG cells forming the TN show peak frequencies at the L6 level and the SG cells forming the same nerve, also at the L6 level in most cases. The bulk of motoneurons, DRG and SG cells forming the CPN and TN are concentrated in two segmental levels. For CPN the motoneurons measure between 14-76 micron in their average somal diameters and for TN, 16-70 micron. The majority of them (65.5% for CPN motoneurons and 72% for TN motoneurons) have average somal diameters greater than 38 micron. The size spectrum of the DRG cells forming the CPN is similar to that of DRG cells forming the TN, being 12-78 micron for CPN and 10-76 micron for TN. The sympathetic neurons forming the CPN (measuring 10-44 micron) have a larger size spectrum than those forming the TN (measuring 6-33 micron). The diameter spectrum (3-20 micron for TN and 2-19 micron for CPN) and peak frequency distributions (10 micron for both TN and CPN) of the myelinated fibres present in the CPN and TN are also similar, with the CPN fibres skewing towards a slightly larger size. Many of the fibres in the young and semi-adult monkeys are not yet myelinated.
The male, pupa and mature larva of Simulium (Asiosimulium) wanchaii Takaoka & Choochote, one of the four species of the small Oriental black fly subgenus Asiosimulium, are described for the first time based on samples collected from Thailand. The male S. (A.) wanchaii is characterized based on the enlarged hind basitarsus and the ventral plate which is much wider than long. The pupa and larva are characterized by the gill with 19 filaments and the deep postgenal cleft, respectively. Keys are provided to identify all the four species of the subgenus Asiosimulium for females, males, pupae and mature larvae.
This study was conducted to record the histological features of the gastrointestinal tract of wild Indonesian shortfin eel, Anguilla bicolor bicolor (McClelland, 1844), captured in Peninsular Malaysia. The gastrointestinal tract was segmented into the oesophagus, stomach, and intestine. Then, the oesophagus was divided into five (first to fifth), the stomach into two (cardiac and pyloric), and the intestine into four segments (anterior, intermediate, posterior, and rectum) for histological examinations. The stomach had significantly taller villi and thicker inner circular muscles compared to the intestine and oesophagus. The lamina propria was thickest in stomach, significantly when compared with oesophagus, but not with the intestine. However, the intestine showed significantly thicker outer longitudinal muscle while gastric glands were observed only in the stomach. The histological features were closely associated with the functions of the different segments of the gastrointestinal tract. In conclusion, the histological features of the gastrointestinal tract of A. b. bicolor are consistent with the feeding habit of a carnivorous fish.
Recent linyphiid collections from Laos as well as some additional specimens from Thailand and West Malaysia are examined. Six species and two genera are described as new to science: Bathyphantes paracymbialis n. sp., Nematogmus asiaticus n. sp., Theoa hamata n. sp.; Asiagone n. gen. is erected for Asiagone signifera n. sp. (type species) and A. perforata n. sp.; Laogone n. gen. is established for Laogone cephala n. sp. The following new synonyms are proposed: Gorbothorax Tanasevitch, 1998 n. syn. = Nasoona Locket, 1982; Paranasoona Heimer, 1984 n. syn. and Millplophrys Platnick, 1998 n. syn. = Atypena Simon, 1894; Gorbothorax ungibbus Tanasevitch, 1998 n. syn. = Oedothorax asocialis Wunderlich, 1974; Hylyphantes birmanicus (Thorell, 1895) n. syn. = H. graminicola (Sundevall, 1830). The following new combinations are proposed: Atypena cirrifrons (Heimer, 1984) n. comb. ex from Paranasoona; A. pallida (Millidge, 1995) and A. crocatoa (Millidge, 1995) both n. comb. ex Millplophrys; Nasoona asocialis (Wunderlich, 1974) n. comb. ex Oedothorax Bertkau, 1883; N. asocialis (Wunderlich, 1974), N. comata (Tanasevitch, 1998), N. conica (Tanasevitch, 1998), N. setifera (Tanasevitch, 1998) and N. wunderlichi (Brignoli, 1983), all n. comb. ex Gorbothorax. Eight linyphiid species are newly recorded from Laos: A. cirrifrons (Heimer, 1984), Bathyphantes floralis Tu & Li, 2006, Hylyphantes graminicola (Sundevall, 1830), Nasoona asocialis, N. crucifera (Thorell, 1895), Nasoonaria sinensis Wunderlich & Song, 1995, Neriene birmanica (Thorell, 1887), and N. oxycera Tu & Li, 2006. The linyphiid spider fauna of Laos currently contains 15 species and is unusually highly specific. All species, except the Palearctic H. graminicola, are probably represented by Southeastern Asian or Oriental autochthons.
Seven new Psechrus species are described from South East Asia: P. arietinus sp. nov.(♂♀, Vietnam), P. insulanus sp. nov.(♂, Thailand), P. ampullaceus sp. nov.(♂♀, Vietnam), P. omistes sp. nov.(♂, Indonesia, Sumatra), P. quasillus sp. nov.(♂♀, Malaysia, Borneo), P. huberi sp. nov.(♀, Philippines), and P. wade sp. nov.(♂, Philippines). For the following species, new records are listed and intraspecific variation is discussed and illustrated: P. libelti Kulczyński, 1908, P. norops Bayer, 2012, P. rani Wang & Yin, 2001, P. khammouan Jäger, 2007, P. luangprabang Jäger, 2007, P. jaegeri Bayer, 2012, P. obtectus Bayer, 2012, P. kenting Yoshida, 2009 and P. crepido Bayer, 2012, and Fecenia protensa Thorell, 1891. The latter species is recorded from Vietnam for the first time. P. norops, P. libelti and an unidentified Psechrus species from Baluno, Mindanao are for the first time characterised and illustrated by their pre-epigynes and pre-vulvae.
Lethrinitrema gibbus n. g., n. sp. and L. dossenus n. sp. are described from the fish Lethrinus rubrioperculatus Sato collected off New Caledonia, South Pacific. Members of Lethrinitrema n. g. (Ancyrocephalidae) are characterised by having two pyriform haptoral reservoirs and ventral anchors with lateral grooves. The elongate tubular distal end of each reservoir bifurcates, draining into a superficial lateral groove on each side of the ventral anchors. The haptoral reservoirs are postulated to store secretory products which assist in attachment to the host. Lethrinitrema spp. also possess tandem gonads, a male copulatory organ without an accessory piece or with thinly sclerotised accessory piece, and a dextrolateral, non-sclerotised vaginal bulb. The two new species have small, poorly demarcated haptors with small haptoral armament and a crown-like piece on the tip of the inner root of the ventral anchors. They differ from each other in the shape and size of the ventral bar and male copulatory organ (40-45 μm in length in L. gibbus vs 24-30 μm in L. dossenus). Three other species, previously included in Haliotrema Johnston & Tiegs, 1922, are transferred to Lethrinitrema, i.e. L. chrysostomi (Young, 1968) n. comb., L. fleti (Young, 1968) n. comb. (both briefly redescribed from paratypes) and L. lethrini (Yamaguti, 1937) n. comb. All species of Lethrinitrema parasitise Lethrinus spp. (Lethrinidae), and there is evidence for the existence of further Lethrinitrema spp. on Lethrinus spp. in the Indo-Pacific region.
Anatomical descriptions of the lateral retinaculum have been published, but the attachments, name or even existence of its tissue bands and layers are ill-defined. We have examined 35 specimens of the knee. The deep fascia is the most superficial layer and the joint capsule is the deepest. The intermediate layer is the most substantial and consists of derivatives of the iliotibial band and the quadriceps aponeurosis. The longitudinal fibres of the iliotibial band merge with those of the quadriceps aponeurosis adjacent to the patella. These longitudinal fibres are reinforced by superficial arciform fibres and on the deep aspect by transverse fibres of the iliotibial band. The latter are dense and provide attachment of the iliotibial band to the patella and the tendon of vastus lateralis obliquus. Our study identifies two important new findings which are a constant connection of the deep fascia to the quadriceps tendon superior and lateral to the patella, and, a connection of the deeper transverse fibres to the tendon of vastus lateralis obliquus.
The extensor digitorum (ED) muscle of the hand originates from the lateral condyle of the humerus and splits into four tendons; each for one phalanx except the thumb. Literature reports have described multiple tendons (usually two) to each digit but in the presented study we observed four tendons to the ring finger, what is rare. During a routine dissection of the cadavers, we observed an anomalous arrangement of the ED tendon on the left hand of a 42-year-old male. The anomalous tendons to the ring finger were studied in detail, the surrounding structures were carefully delineated and the specimen was photographed. The ED muscle originated as usual from the lateral condyle of the humerus, continued downwards, passing inferiorly to the extensor retinaculum to split into individual tendons for each of the digits. There was a single tendon to the index, middle and ring finger as usual but the ring finger displayed four tendons. All the tendons attached to the phalanges were as described in anatomy textbooks. The arrangement of the anomalous tendons of ED to each of the digits is not uncommon, but existence of four tendons to the ring finger is extremely rare. The increased number of tendons to the ring finger may increase the extension component of the ring finger. Anatomical knowledge of the tendons of the extensor muscles of the hand may be also beneficial for hand surgeons performing graft operations (Fig. 2, Ref. 11). Full Text (Free, PDF) www.bmj.sk.
Fine dissection was carried out in 79 facial halves from formalin fixed Malaysian adult cadavers of various races, to trace the extracranial part of the facial nerve and its peripheral branches. The facial nerve trunk, after leaving the stylomastoid foramen was located at a depth of 1 to 2 cm from the skin in the vagino-mastoid angle. It bifurcates at the posterior border of the ramus of the mandible and in 3.8% trifurcation was found. Mean distance of bifurcation from the angle of the mandible was 28.06 mm and 81.0% were within the range of 21 to 35 mm. The branching patterns were classified into six types, and the frequency of occurrence was type I 11.39%, type II 15.9%, type III 34.18%, type IV 18.98%, type V 7.59% and type VI 12.67%. Type I, a classical text book pattern was found to be one of the least common patterns. There is no significant difference in percentage of each type between the present study and that of Koreans, though some differences with Caucasians were noted in three uncommon types. The frontal branch could be outlined between the two diverging lines from the earlobe to the lateral ends of the eyebrow and the highest frontal crease. Posterior to the facial artery, the mandibular branch was seen passing below the inferior border of the mandible in 20%; anterior to the artery, this nerve divides into one to four branches. In almost all the cases, branches to the mentalis and the depressor labii inferioris muscles and infrequently branches to the depressor angular oris were seen below the inferior border of the mandible.(ABSTRACT TRUNCATED AT 250 WORDS)
Geographical variation was examined morphologically in the common tree shrew (Tupaia glis) in some Indochinese and Malayan regions. Osteometrical examination and principal component analysis elucidated the morphological differences among various populations. The populations from southern and western Thailand were distinguished morphologically from the other populations. Variation in males from south Thailand and Kuala Lumpur suggests that the Isthmus of Kra may have an influence on the variation of skull morphology. However, the Isthmus of Kra was not completely considered as a factor of geographical separation in this species, because we could not confirm the separation in skull size and shape between the localities at least in females. While, the Kanchanaburi population in western Thailand was significantly smaller than the other population in skull size, and constituted the morphologically separable group in our study.
Rattan is an important climbing palm taxon in Malaysian tropical rain forests. Many rattan species have unique structures directly associated with certain ant species. In this study, four rattan species (Daemonorops lewisiana, Calamus castaneus, Daemonorops geniculata and Korthalsia scortechinii) were inspected and documented in a field survey concerning their relationships with several ant species. We noticed that two rattan species (D. lewisiana and C. castaneus) were more likely to be associated with ants compared to their neighbouring rattan (Plectomia griffithii). However, D. lewisiana and C. castaneus did not directly provide shelters for ant colonies, but possessed unique structures: upward-pointing spines and funnel-shaped leaves, which are equipped to collect more litter than P. griffithii. To test our litter collecting hypothesis, we measured the inclination of spines from the stem. Our results showed the presence of ant colonies in the litter-collecting rattans (D. lewisiana and C. castaneus), which was significantly higher compared to a non-litter-collecting rattan (P. griffithii). We propose a complex and novel type of adaptation (litter-collection and provision of nesting materials) for rattans, which promotes interactions between the rattan and ants through the arrangements of leaves, leaflets, and spines. In return, the rattan may benefit from ants' services, such as protection, nutrient enhancement, and pollination.
The skeletal remains of Pleistocene anatomically modern humans are rare in island Southeast Asia. Moreover, continuing doubts over the dating of most of these finds has left the arrival time for the region's earliest inhabitants an open question. The unique biogeography of island Southeast Asia also raises questions about the physical and cultural adaptations of early anatomically modern humans, especially within the setting of rainforest inhabitation. Within this context the Deep Skull from the West Mouth of the Niah Caves continues to figure prominently owing to its relative completeness and the greater certainty surrounding its geological age. Recovered along with this partial cranium in 1958 were several postcranial bones including a partial femur which until now has received little attention. Here we provide a description and undertake a comparison of the Deep Skull femur finding it to be very small in all of its cross-sectional dimensions. We note a number of size and shape similarities to the femora of Indigenous Southeast Asians, especially Aeta people from the Philippines. We estimate its stature to have been roughly 145-146 cm and body mass around 35 kg, confirming similarities to Aeta females. Its extreme gracility indicated by low values for a range of biomechanical parameters taken midshaft meets expectations for a very small (female) Paleolithic East Asian. Interestingly, the second moment of area about the mediolateral axis is enlarged relative to the second moment of area about the anteroposterior axis, which could potentially signal a difference in activity levels or lifestyle compared with other Paleolithic femora. However, it might also be the result of sexual dimorphism in these parameters as well as possibly reflecting changes associated with aging.
The female, male, pupa and mature larva of Simulium (Simulium) poolpholi sp. nov. collected from a large and seasonal stream in northeastern Thailand are described. This new species is placed in the S. striatum species-group by the female sternite 8 concave posteromedially in form of the inverted-U shape, ovipositor valve with a ventrally produced process along its inner margin, male ventral plate saddle-shaped, style with a basal protuberance, and pupal gill with 10 filaments. It is morphologically similar to S. (S.) phraense Takaoka, Srisuka & Saeung from northern Thailand by lacking annular ridges on the surface of pupal gill filaments but it is distinguished from the latter species by the arrangement of pupal gill filaments. Molecular analysis using the fast-evolving nuclear big zinc finger (BZF) gene shows that S. (S.) poolpholi sp. nov. formed a distinct clade, being separated from the seven other Thai species of this species-group by a genetic distance of 1.84-4.55%. Our discovery increases the number of species in the S. striatum species-group in Thailand to nine.
Among Oriental anopheline mosquitoes (Diptera: Culicidae), several major vectors of forest malaria belong to the group of Anopheles (Cellia) leucosphyrus Dönitz. We have morphologically examined representative material (> 8000 specimens from seven countries) for taxonomic revision of the Leucosphyrus Group. Six new species are here described from adult, pupal and larval stages (with illustrations of immature stages) and formally named as follows: An. latens n. sp. (= An. leucosphyrus species A of Baimai et al., 1988b), An. cracens n. sp., An. scanloni n. sp., An. baimaii n. sp. (formerly An. dirus species B, C, D, respectively), An. mirans n. sp. and An. recens n. sp. Additionally, An. elegans (James) is redescribed and placed in the complex of An. dirus Peyton & Harrison (comprising An. baimaii, An. cracens, An. dirus, An. elegans, An. nemophilous Peyton and Ramalingam, An. scanloni and An. takasagoensis Morishita) of the Leucosphyrus Subgroup, together with An. baisasi Colless and the An. leucosphyrus complex (comprising An. balabacensis Baisas, An. introlatus Baisas, An. latens and An. leucosphyrus). Hence, the former Elegans Subgroup is renamed the Hackeri Subgroup (comprising An. hackeri Edwards, An. pujutensis Colless, An. recens and An. sulawesi Waktoedi). Distribution data and bionomics of the newly defined species are given, based on new material and published records, with discussion of morphological characters for species distinction and implications for ecology and vector roles of such species. Now these and other members of the Leucosphyrus Group are identifiable, it should be possible to clarify the medical importance and distribution of each species. Those already regarded as vectors of human malaria are: An. baimaii[Bangladesh, China (Yunnan), India (Andamans, Assam, Meghalaya, West Bengal), Myanmar, Thailand]; An. latens[Borneo (where it also transmits Bancroftian filariasis), peninsular Malaysia, Thailand]; probably An. cracens (Sumatra, peninsular Malaysia, Thailand); presumably An. scanloni (Thailand); perhaps An. elegans (the Western Ghat form of An. dirus, restricted to peninsular India); but apparently not An. recens (Sumatra) nor An. mirans[Sri Lanka and south-west India (Karnataka, Kerala, Tamil Nadu)], which is a natural vector of simian malarias. Together with typical An. balabacensis, An. dirus and An. leucosphyrus, therefore, the Leucosphyrus Group includes about seven important vectors of forest malaria, plus at least a dozen species of no known medical importance, with differential specific distributions collectively spanning > 5000 km from India to the Philippines.
Male worms of Ancylostoma braziliense, A. ceylanicum, A. kusimaense, A. malayanum, A. duodenale, A. caninum, A. tubaeforme, Agriostomum vryburgi and Cyclodontostomum purvisi have the external appendages beside the anogenital aperture. These anogenital structures are morphologically similar and are assumed to be homologous among the species with three pairs of teeth or more. In hookworms with two pairs of teeth, the anogenital structures are complex. Anogenital features can be used as a taxonomic character in separating the species.