Refine
Document Type
- Article (4)
- Part of Periodical (3)
Language
- English (7)
Has Fulltext
- yes (7)
Is part of the Bibliography
- no (7)
Keywords
- morphometrics (7) (remove)
Institute
Two new species of the genus Sectonema from natural habitats of northern Vietnam are studied. This paper includes their descriptions, measurements, line illustrations, and light microscope (LM) and scanning electron microscope (SEM) pictures. Sectonema tropicum sp. nov. is characterized by a 2.56– 3.24 mm long body, 19–21 μm broad lip region, odontostyle 20–21 μm long at its ventral side, 730– 834 μm long neck, pharyngeal expansion occupying 52–59% of total neck length, uterus a simple tube-like structure 150–242 μm long or 1.2–2.5 times the body diameter, pars refringens vaginae present, V = 48–52, short (31–40 μm, c = 70–91, c’ = 0.5–0.6) and rounded tail, 91–97 μm long spicules, and only one weakly developed ventromedian supplement. Sectonema vietnamense sp. nov. is characterized by its slender (a = 33–49) and 2.71–4.25 mm long body, 14–16 μm broad lip region, odontostyle 8–9 μm long at its ventral side, 716–918 μm long neck, pharyngeal expansion occupying 63–67% of total neck length, uterus simple and 209–242 μm long or 2.5–2.9 times the corresponding body diameter, pars refringens vaginae absent, V = 54, short (34–39 μm, c = 70–115, c’ = 0.6–0.8) and rounded tail, 59–75 μm long spicules, and three or four irregularly spaced ventromedian supplements bearing hiatus. Both species are also characterized by their nearly continuous lip region, an atypical feature in this genus. Molecular analysis of S. tropicum sp. nov. confirms that Sectonema is a natural (monophyletic) taxon, very close to Metaporcelaimus.
The birdwing butterfly Trogonoptera brookiana (Wallace, 1855) is a well-known conservation icon, yet questions remain about the infraspecific status of regional populations. The eastern Peninsular Malaysian population has been described as the subspecies mollumar d’Abrera, Doggett & Parker, 1976, but its status as a subspecies distinguishable from the taxon trogon (Vollenhoven, 1860) in Sumatra has been disputed. Wing characters and measurements of specimens from the two regions were therefore examined quantitatively using discriminant function and correspondence analyses. Eastern Peninsular specimens differ on average from Sumatran specimens in having more extensive green, especially in the female. This is reflected in many of the measurements and characters analysed. Females from the Peninsula also have a characteristically blacker upperside ground colour in which the outer areas of both wings barely contrast with the black veins and forewing cell. The extent of these differences enables a reliable differentiation of the females of both regions. The magnitude and consistency of differences are comparable to that between other subspecies of undisputed status. Behavioural differences also exist. The name mollumar therefore merits subspecific status. In addition, we consider the male forms walshi Haugum & Low, 1982 and walshoides Haugum & Low, 1982 to be chemically discoloured specimens of trogon rather than biological forms.
The Changhsingian (Late Permian) Hambast Formation of sections at Baghuk Mountain (Central Iran) has yielded diverse ammonoid assemblages composed of the genera Pseudogastrioceras, Shevyrevites, Arasella, Dzhulfites, Paratirolites, Clivotirolites gen. nov., Esfahanites gen. nov., Alibashites, Lutites gen. nov., Abichites and Stoyanowites. The succession of ammonoid species allows for a subdivision of the rock unit into biozones, which largely correlate with the occurrences in north-western Iran. Three new genera, Clivotirolites Korn & Hairapetian gen. nov., Esfahanites Korn & Hairapetian gen. nov. and Lutites Korn & Hairapetian gen. nov., as well as 19 new species are described: Shevyrevites corrugatus Korn & Hairapetian sp. nov., Arasella falcata Korn & Hairapetian sp. nov., Dzhulfites brevisellatus Korn & Hairapetian sp. nov., Paratirolites rubens Korn & Hairapetian sp. nov., Paratirolites lanceolobatus Korn & Hairapetian sp. nov., Paratirolites robustus Korn & Hairapetian sp. nov., Paratirolites baghukensis Korn & Hairapetian sp. nov., Paratirolites aduncus Korn & Hairapetian sp. nov., Clivotirolites decoratus Korn & Hairapetian gen. et sp. nov., Clivotirolites petilus Korn & Hairapetian gen. et sp. nov., Esfahanites armatus Korn & Hairapetian gen. et sp. nov., Lutites paucis Korn & Hairapetian gen. et sp. nov., Lutites lyriformis Korn & Hairapetian gen. et sp. nov., Lutites profundus Korn & Hairapetian gen. et sp. nov., Lutites alius Korn & Hairapetian gen. et sp. nov., Lutites plicatus Korn & Hairapetian gen. et sp. nov., Abichites ovalis Korn & Hairapetian sp. nov., Abichites infirmus Korn & Hairapetian sp. nov. and Stoyanowites parallelus Korn & Hairapetian sp. nov. The material described here is, together with the material from NW Iran, the most diverse assemblage known from the interval before the end-Permian mass extinction.
The cytoskeleton is crucial for defining neuronal-type-specific dendrite morphologies. To explore how the complex interplay of actin-modulatory proteins (AMPs) can define neuronal types in vivo, we focused on the class III dendritic arborization (c3da) neuron of Drosophila larvae. Using computational modeling, we reveal that the main branches (MBs) of c3da neurons follow general models based on optimal wiring principles, while the actin-enriched short terminal branches (STBs) require an additional growth program. To clarify the cellular mechanisms that define this second step, we thus concentrated on STBs for an in-depth quantitative description of dendrite morphology and dynamics. Applying these methods systematically to mutants of six known and novel AMPs, we revealed the complementary roles of these individual AMPs in defining STB properties. Our data suggest that diverse dendrite arbors result from a combination of optimal-wiring-related growth and individualized growth programs that are neuron-type specific.
We report the rediscovery of the Pied Butterfl y Bat, Glauconycteris superba Hayman, 1939, 40 years after this species was last recorded. The new specimen from Mbiye Island, Democratic Republic of the Congo, is compared with the type specimens of G. s. superba and G. superba sheila Hayman, 1947 and a specimen from Matonguiné, Ivory Coast. The variation in the striking colouration of the pelage as well as in morphometric data is considered to be individual rather than geographic variation and we tentatively regard G. s. sheila as a synonym of the nominate form. Despite the wide distribution of this species in the tropical forest zone of West and Central Africa, only four specimens from four localities are known to date, which might indicate very specific habitat preferences. Contemporary land cover information around historic collection sites shows degraded landscapes. Given the highly uncertain area of occupancy of this species, we suggest changing the status of G. superba in the IUCN Red List of Threatened Species from “Least Concern” to “Data Defi cient”.
Thylacocephalans are enigmatic euarthropods, known at least from the Silurian to the Cretaceous. Despite remaining uncertainties concerning their anatomy, key features can be recognised such as a shield enveloping most of the body, hypertrophied compound eyes, three pairs of raptorial appendages and a posterior trunk consisting of eight up to 22 segments bearing appendages and eight pairs of gills. Well-known for its euarthropod diversity, the La Voulte-sur-Rhône Lagerstätte (Callovian, Middle Jurassic, France) has provided many remains of four thylacocephalan species so far: Dollocaris ingens, Kilianicaris lerichei, Paraostenia voultensis and Clausocaris ribeti. In this paper, we study the type material as well as undescribed material. The re-description of La Voulte thylacocephalans reveals an unexpected diversity, with the description of two new species, Austriocaris secretanae sp. nov. and Paraclausocaris harpa gen. et sp. nov., and of specimens of Mayrocaris, a taxon originally described from Solnhofen Lagerstätten. We also reassign Clausocaris ribeti to Ostenocaris. The reappraisal of La Voulte thylacocephalans also provides important insight into the palaeobiology of Thylacocephala. New key anatomical features are described, such as an oval structure or a putative statocyst, which indicate a nektonic or nektobenthic lifestyle. Finally, we document a juvenile stage for Paraostenia voultensis.
We provide keys, descriptions and illustrations for 16 species of Scoliidae Latreille, 1802 found in Hong Kong, of which nine are new records for the territory, one is new to China and one is new to science: Scolia pakshaoensis sp. nov. The status of one species (Megacampsomeris sp. 1) remains uncertain; it may represent an additional new species.