Periophthalmus spilotus, a new species of mudskipper from Sumatra (Gobiidae: Oxudercinae)

A new species of mudskipper,Periophthalmus spilotus, is described on the basis of 16 specimens from Sumatra, Indonesia. It differs from other species ofPeriophthalmus by the following combination of characters: pelvic fins totally united into rounded disk; first dorsal fin high, greyish, no spots on fin nor elongate spines; second dorsal fin typically with 14 total elements; anal fin typically with either 14 or 15 total elements; length of anal-fin base 21.8–29.0% SL; and length of second dorsal-fin base 22.5–26.7% SL. This species is most similar to, and probably most closely related to,P. chrysospilos.     

Aerial ventilatory responses of the mudskipper, Periophthalmodon schlosseri, to altered aerial and aquatic respiratory gas concentrations

Periophthalmodon schlosseri is a mudskipper which uses the vascularized buccopharyngeal cavity as a respiratory organ. The fish construct mud burrows that contain hypoxic water, but store air inside the burrows. Because the burrow gas is frequently hypoxic and hypercapnic, the effects of altered respiratory gas concentrations on the aerial ventilation frequency (V(F)), inspiratory tidal volume (V(T)) and minute volume (V(M)=V(F)xV(T)) of P. schlosseri were studied by pneumotachography. Both total buccopharyngeal gas volume (V(BP)) and V(T) scaled significantly with body mass (mass exponents=1.10 and 1.03, respectively), and V(T)/V(BP) was 0.54+/-0. 05 (S.E.M., n=6). V(BP), expressed as a percentage of body volume, was much higher (16%) than in other air-breathing gobies (2-4%). When fish respired in normoxic air and water, V(F) was 0.25+/-0.04 breaths min(-1), V(T) 7.6+/-0.6 ml 100 g(-1), and V(M) 1.80+/-0.18 ml 100 g(-1) min(-1). Aquatic hypoxia did not significantly affect V(F), V(T), or V(M). In both moderate (P(O(2))=10 kPa) and severe (P(O(2))=5 kPa) aerial hypoxia, V(F) and V(M) increased significantly. V(T) increased significantly only during severe aerial hypoxia. In aerial hypercapnia, V(F) and V(M) increased significantly.     

Size, growth and reproductive biology of the giant mudskipper, Periophthalmodon schlosseri (Pallas, 1770), in Malaysian waters

The size, growth and reproductive biology of the giant mudskipper, Periophthalmodon schlosseri, was studied in the inter‐tidal mudflat of a mangrove swamp along a 0.4–0.6 × 5 km stretch of the Sepang coastal waters, Selangor Malaysia. The size ranges of the giant mudskipper specimens caught in the study area were between 10–27.5 cm TL (20.6 ± 3.1 cm) for males and 14.5–28.5 cm TL (21.9 ± 2.3 cm) for females. Male to female sex ratio during the study was 1 : 1.1. The estimated von Bertalanffy growth parameters were L_∞ = 29 cm and K = 1.4 year^?1, with a growth performance index of Ø′ = 3.1. Otolith microstructure analysis revealed a strong correlation (Female: r = 0.920, n = 35; Male: r = 0.943, n = 41, P < 0.05) between the number of daily rings (number of days old) over the respective size ranges of male (8.5–19.5 cm SL) and female fish (11.8–22.3 cm SL). Four maturity stages were described to follow gonadal development based on external features; these stages were further validated through histological examination of the ovary and oocyte diameter measurements. The gonadal development cycle of P. schlosseri was asynchronous, as marked by the random mixture of early stages oocytes (diameter: 70.7 ± 14.9 μm) to matured stages (356.9 ± 20.2 μm), and had a prolonged spawning season extending from June to October. Monthly fluctuation of the gonadosomatic and hepatosomatic indices for this species was highly correlated (r = 0.126, P < 0.05).     

Taxonomical and morphological notes on two species of mudskippers, Periophthalmus walailakae and Periophthalmodon schlosseri (Teleostei: Gobiidae) from Singapore

The mudskipper Periophthalmus walailakae is recorded from Singapore, where it was previously misidentified as Periophthalmodon schlosseri, with which it is syntopic. Periophthalmus walailakae is distinguished from its congeners by the following combination of characters: pelvic fins completely united and shaped like a disk, and first dorsal fin dark brown or black, with a rounded posterior edge and a white distal margin. This species most closely resembles Pn. schlosseri but has one row of teeth on the upper jaw, scales on the isthmus, and a different upper lip and jaw morphology. Contrary to an earlier report, scales are present on the snout, interorbital, and isthmus of Ps. walailakae. The two species can also be distinguished by size, external morphology, and body color patterns.     

Distribution and habitat requirements of oxudercine gobies (Gobiidae: Oxudercinae) along the Straits of Malacca

Indonesian and Malaysian tidal flats along the Straits of Malacca were surveyed to determine the distributions of oxudercine gobies and their habitat conditions. Eight species from Penang Island and Selangor, Malaysia, and 12 species from Tebing Tinggi and Bengkalis Islands, Sumatra, were collected, including 2 species that had not been previously known to occur in these areas. Depending on the species, the habitats varied from sandy to muddy, level to sloped, exposed to immersed, wet to dry, and seashore to tidal river reaches.     

Complete mitochondrial genome of the mudskipper Boleophthalmus pectinirostris (Perciformes, Gobiidae): repetitive sequences in the control region

The mudskipper, Boleophthalmus pectinirostris (Perciformes, Gobiidae), is an amphibious gobioid fish. In this paper, the complete mitochondrial genome of B. pectinirostris was firstly determined. The mitogenome (17,111 bp) comprises 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 putative control region. 130-bp tandem repeat was identified in the control region, which was almost identical among the 10 individuals examined, and three different frequencies of the repeat unit (five, six or seven) were found among these individuals.     

Length–weight relationships for three species of mudskippers (Gobiidae: Oxudercinae) in the coastal areas of the Persian Gulf, Iran

Length–weight relationships, W  =  aL ^b , were calculated for three species of mudskippers: Scartelaos tenuis , Periophthalmus waltoni and Boleophthalmus dussumieri from the Iranian coast of the Persian Gulf. Values of b ranged from 2.10 to 2.86 for both sexes at seven sites for the three species.     

A new marine gobiid species of the genus Clariger Jordan & Snyder (Gobiidae, Teleostei) from Taiwan

A new species of Clariger Jordan & Snyder, 1901 was collected from northern Taiwan. The genus was previously known only from Japanese waters. This discovery is the first formal and southernmost record of these marine gobies from the waters of subtropical Taiwan. The new species, Clariger taiwanensissp. n., is distinguished from its congeners by a unique combination of features: (1) fin rays: dorsal-fin rays III, I/8; anal-fin rays modally I/8; and pectoral-fin rays modally 19 (2+16+1); (2) longitudinal dermal ridge on head with 6 barbels; and (3) specific coloration pattern: head and trunk dark brown with scattered pale spots and blotches; cheek, ventral portion of head sometimes pale with deep brown spots; pectoral-fin base with a dark brown band; and caudal fin mostly dark brown proximally and with alternating and irregular dark brown and pale bands distally. A diagnostic key to all nominal species from Japan and Taiwan is provided.     

Four new species of dwarfgobies (Teleostei: Gobiidae: Eviota) from the Austral,Gambier, Marquesas and Society Archipelagos,French Polynesia

Four new species of Eviota (Teleostei: Gobiidae) are described from French Polynesia. Eviota hinanoae occurs from the Gambier, Austral and Society Archipelagos and differs from its closest relatives primarily in sensory pore pattern, having cuplike male urogenital papilla, and in lacking prominent dark pigmentation on the base of the pectoral fin. Three other new species, E. dorsimaculata, E. lacrimosa and E. deminuta, are known only from the Marquesas Islands and are distinguished from congeners by differences in pigmentation, sensory pore pattern, urogenital papilla shape, the number of rays in the dorsal and anal fins, and the length of the fifth pelvic-fin ray. Eviota deminuta represents one of the smallest known species of Eviota and features reductions in several morphological characters, including the loss of all head pores. Three of the new species are included in a phylogenetic analysis based on mitochondrial cytochrome c oxidase-I, along with 21 additional species of Eviota.     

Trophic morphology of the coral-associated genus Gobiodon (Teleostei: Gobiidae) from the Red Sea

Trophic morphology plays a major role in niche diversification among the highly diverse fish fauna of coral reefs. It gives insight into feeding types and is useful in taxonomy, as it can be used to differentiate between species and to estimate phylogenetic relationships. The gobiid genus Gobiodon comprises obligate coral dwelling species that are widespread on Red Sea and Indo-Pacific reefs. Yet very little is known about their ecology and behaviour of feeding. In this study, viscerocranial and oral jaw morphology was investigated in seven species of Gobiodon that occur in the Red Sea. Osteological analyses were carried out on enzyme cleared and alizarin red stained specimens. Shape variation of the viscerocranium was analyzed using a landmark-based geometric morphometric method on digital scans of hand drawings and visualized in thin-plate splines. Shape was determined by placing landmarks on skeletal elements in their articulated state. Morphology of the dentary and premaxilla was examined in further detail after disarticulation. A combination of landmarks and semilandmarks was applied to digital photographs of the oral jaws. It was shown that orbit size influences viscerocranial morphology by delimiting the lower jaw articulation angle. The premaxilla differs both in its extent and direction of curvature and in the structure of the articular process. Form changes in the dentary are mainly caused by variation of curvature and depth. A significant relationship between oral jaw shape and the number of anterior rows of teeth was found. Morphological diversity of selected elements is used to generate hypotheses concerning the trophic biology and niche diversification of Gobiodon . Brief dietary and in situ behavioural observations were carried out to further develop and test hypotheses.     

Gross and fine structure of the antennal circulatory organ in cockroaches (Blattodea,Insecta)

The antennal circulatory organ of Periplaneta americana and Blaberus craniifer was investigated by light and electron microscopy. This organ consists of two pulsatile ampullae located near the antennal base which are interconnected by a large transverse muscle and associated blood vessels which run into the antennae. Diastole is caused simultaneously in both ampullae by the transverse muscle. Systole is produced passively by the elasticity of the wall of the ampullae and minute accessory tendons. Both elastic structures contain fine unbanded extracellular filaments. The antennal vessels possess two distinct regions: a proximal convoluted region lying within the hemocoel of the head and a narrower distal region running through the antenna and opening near the antennal apex. The length of the proximal portion increases markedly during ontogeny in correlation with the growing antenna. Its wall consists of a high-prismatic epithelium ensheathed by a thick layer of collagen fibrils. The structure of the wall cells is comparable to that found in some salt transporting epithelia: it shows a polar organization with basal infoldings, a large number of mitochondria, and typical arrangement of the junctions or mitochondrial-scalariform junctional complexes. The possible physiological function of this epithelium in ionic or osmoregulation of the hemolymph entering the antenna is discussed. The wall of the distal vessel region consists of a flat single-layered epithelium and seems to be specialized only for delivery of hemolymph to antennae. The structure and function of the antennal heart in cockroaches is compared to that found in other insects.     

Gross and microscopic anatomy of the kidney of the West Indian manatee, Trichechus manatus (Mammalia: Sirenia)

Examination of the gross and microscopic anatomy of the kidney of the West Indian manatee, Trichechus manatus, revealed that: (1) the medulla is about 6 times thicker than the cortex; (2) juxtamedullary glomeruli have a mean diameter 1.3 times greater than that of cortical glomeruli; (3) juxtamedullary glomeruli have 1.7 times as much volume as cortical glomeruli; (4) there are about twice as many cortical glomeruli as juxtamedullary glomeruli per square millimeter of cortical tissue, and (5) the vasa recta are closely juxtaposed to the thin loops of Henle in the outer medulla. Many of these results suggest an enhanced urine-concentrating ability in this species.     

Floral anatomy of the Styracaceae, including observations on intra-ovarian trichomes

DICKISON, W. C., 1993. Floral anatomy of the Styracaceae, including observations on intra-ovarian trichomes All eleven genera of the Styracaceae were examined with respect to floral morphology and anatomy. Floral structure and vascularization are described in detail. Flowers of the family exhibit different degrees and patterns of specialization. All Styracaceae show some degree of basal non-divergence of perianth members, forming a hypanthium that is adnate to the ovary wall to a lesser or greater extent. The extent of reduction and amplification in the number of sepals, petals, stamens, and carpels varies widely among genera, and generally the non-divergence, decrease, or increase in parts is not equally pronounced in the different whorls of the same flower. Genera cannot be readily aligned in an intergrading sequence of morphological advancement. Stamen form and anatomy is variable. A fibrous endothecium ranges from well-developed to weakly formed or absent. A nearly uniform feature of the styracaceous gynoecium is the presence of incompletely septate ovaries. The major points of variation in the floral vascular system relate to the number, mode of origin, and degree of independence of sepallary traces; degree of independence of the androecial vasculature; the level at which the common petal and petalad-stamen or sepal and sepalad-stamen bundles separate to their component parts; organization of the ventral ovarian supply; and the occurrence of ventral bundles in the style. Floral vascularization provides evidence that the family was derived from an obdiplostemonous ancestor. A unitegmic ovule is predominant in the family and starch is present in the megagametophyte of some taxa. An unusual feature of the flowers of the Styracaceae is the occurrence of stellate and lignified intra-ovarian trichomes. Numerous similarities in floral morphology and anatomy between Styracaceae and Ericales are pointed out.     

The morphology and ultrastructure of the peripheral olfactory organ in newly metamorphosed coral-dwelling gobies, Paragobiodon xanthosomus Bleeker (Gobiidae, Teleostei)

We examined the peripheral olfactory organ in newly metamorphosed coral-dwelling gobies, Paragobiodon xanthosomus (SL=5.8mm+/-0.8mm, N=15), by the aid of electron microscopy (scanning and transmission) and light microscopy. Two bilateral olfactory placodes were present in each fish. They were oval-shaped and located medio-ventrally, one in each of the olfactory chambers. Each placode had a continuous cover of cilia. The placode epithelium contained three different types of olfactory receptor neurons: ciliated, microvillous and crypt cells. The latter type was rare. Following a pelagic larval phase, P. xanthosomus settle to the reef and form an obligate association with one species of coral, Seriatopora hystrix. Their well-developed olfactory organs likely enable larvae of P. xanthosomus to detect chemical cues that assist in navigating towards and selecting appropriate coral habitat at settlement. Our findings support past studies showing that the peripheral olfactory organ develops early in coral reef fishes.     

Morphology and vascular anatomy of the gills of a primitive air-breathing fish,the bowfin (Amia calva)

Summary The morphology of the gills of a primitive air breather (Amia calva) was examined by light microscopy of semithin sections of gill filaments, and gill perfusion pathways were identified by scanning-electron microscopic analysis of corrosion replicas prepared by intravascular injection of methyl methacrylate. The arrangement of gill filaments and respiratory lamellae is similar to that of teleosts with the exception of an interfilamental support bar that is fused to the outer margins of lamellae on adjacent filaments. The prebranchial vasculature is also similar to that of teleosts, whereas the postbranchial circulation of arches III and IV is modified to permit selective perfusion of the air bladder. Gill filaments contain three distinct vascular systems: (1) the respiratory circulation which receives the entire cardiac output and perfuses the secondary lamellae; (2) a nutrient system that arises from the postlamellar circulation and perfuses filamental tissues; (3) a network of unknown function consisting of subepithelial sinusoids surrounding afferent and efferent margins of the filament and traversing the filament beneath the interlamellar epithelium. Prelamellar arteriovenous anastomoses (AVAs) are rare, postlamellar AVAs are common especially at the base of the filament where they form a dense network of small tortuous vessels before coalescing into a large filamental nutrient artery. Unlike in most teleosts, the outer vascular margins of the lamellae are embedded in the interfilamental support bar and become the sole vasculature of this tissue. Arterial-arterial lamellar bypass vessels were not observed. Previously observed decreases in oxygen transfer across the gills during air breathing can be explained only by redistribution of blood flow between or within the respiratory lamellae.Supported by NSF Grant No. PCM 79-23073The author wishes to thank Miss K. Drajus and D. Kullman for their excellent technical assistance and Dr. W. Gingerich, Mr. J. Crowther and D. Zurn for help in obtaining bowfin     

Gross anatomy of the liver, biliary tree, and pancreas in the black-tailed prairie dog (Cynomys ludovicianus)

The gross anatomy of the liver, extrapetatic biliary tree, sphincter of Oddi, and pancreas in the black-tailed prairie dog (Cynomys ludovicianus), a widely used animal model for investigations into biliary physiology, pathophysiology, and pathology, was studied in 10 animals. The liver consists of 4 lobes, the left lateral, median, right lateral, and caudate. The gallbladder lies on the ventral surface of the right lobule of the median lobe. The cystic and hepatic ducts unite to form the common bile duct which enters the duodenum approximately 5 mm distal to the pylorus. The lower end of the common duct dilates forming an ampulla which is surrounded proximally by a band of circular muscle fibres which constitute the choledochal sphincter. The pancreatic duct opens separately into the duodenum approximately 80 mm from the pylorus. Earlier physiologic studies have demonstrated that the choledochal sphincter has intrinsic motility distinct from the duodenum.     

Evolutionary morphology of the hemolymph vascular system in hermit and king crabs (Crustacea: Decapoda: Anomala)

The morphological transformation of hermit crabs into crab‐like king crabs in the evolution of decapod crustaceans represents a remarkable case of carcinization or evolutionary shaping into a crab‐like form. In this study, we focus on internal organs such as the hemolymph vascular system and adjacent anatomical structures of several Recent hermit crab (Paguridae) and king crab (Lithodidae) species. There are various correspondences in the morphology of the arterial systems in the dorsal cephalothorax of the two taxa, especially with regard to the anterior aorta, anterior lateral arteries, and hepatic arteries. In the pleon, the posterior aorta in both taxa displays a proximal bifurcation and follows an asymmetrical course. The ventral vessel system, on the other hand, which mainly supplies the limbs, differs significantly between the taxa, with pagurids displaying the plesiomorphic condition. The pattern of the ventral vessel system in Lithodidae is influenced by morphological transformations of integumental structures during carcinization. One of these transformations was the broadening of the sternites, which resulted in a widening of the space between the endosternites. In addition, changes in the morphology of the endophragmal skeleton in Lithodidae led to an increase in the potential for intraspecific variability and interspecific variation in the arterial branching pattern. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc.     

Morphology, anatomy and vasculature of leaves in Pinus (Pinaceae) and its evolutionary meaning

The morphology, anatomy and vasculature of Pinus leaves was studied. The results indicate that the Pinus leaf is always supplied with only one single vascular bundle, which is surrounded by a prominent bundle sheath. In several taxa, especially of subgenus Pinus, the vascular bundle may however be subdivided by longitudinal parenchymatic bands in the middle part of the leaf. As a result, the single bundle gets the appearance of two individual bundles, which are surrounded by a common bundle sheath. The general rule that a bundle sheath does sheath only one single bundle, as in other gymno- and angiospermous seed plants, applies therefore also for Pinus. The morphological and anatomical similarities between cladodes of Sciadopitys (Sciadopityaceae) and Pinus leaves are based on a completely different bauplan. The idea of “hidden cladodes” in some Pinaceae is therefore obsolete.