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A new species from the extinct ant genus Eocenomyrma, E. groehnisp. nov., is described based on worker from the Baltic amber (Late Eocene, Priabonian stage, 33.9–37.2 Ma). It the most resembles E. orthospina Dlussky et Radchenko, 2006 by shape of the propodeal spines and by the general appearance, but well differs from the latter by structure of the frontal carinae, which merging with the rugae that extend to the occipital margin; in contrary, the frontal carinae in E. orthospina are short, curve outwards and merge with the rugae, which surround antennal sockets. Additionally, entire head dorsum in E. groehni covered by the slightly sinuous longitudinal rugae, but in E. orthospina the only frons is with the not coarse longitudinal, slightly sinuous rugae, but the lateral parts of the head dorsum and occiput are with reticulation.

Chemical detection is key to various behaviours in both marine and terrestrial animals. Marine species, though highly diverse, have been underrepresented so far in studies on chemosensory systems, and our knowledge mostly concerns the detection of airborne cues. A broader comparative approach is therefore desirable. Marine annelid worms with their rich behavioural repertoire represent attractive models for chemosensory studies. Here, we study the marine wormPlatynereis dumeriliito provide the first comprehensive study of head chemosensory organ physiology in an annelid. By combining microfluidics and calcium imaging, we record neuronal activity in the entire head of early juveniles upon chemical stimulation. We find thatPlatynereisuses four types of organs to detect stimuli such as alcohols, esters, amino acids and sugars. Antennae, but not nuchal organs or palps as generally hypothesised in annelids, are the main chemosensory organs. We report chemically-evoked activity in possible downstream brain regions including the mushroom bodies, which are anatomically and molecularly similar to insect mushroom bodies. We conclude that chemosensation is a major sensory modality for marine annelids, and propose earlyPlatynereisjuveniles as a model to study annelid chemosensory systems.

The scorpionfish Scorpaena decemradiata n. sp. is described from off the coast of Israel in the Gulf of Aqaba, northern Red Sea. The new species is similar to S. porcus Linnaeus, 1758, but is characterized by dorsal fin spines XII, soft dorsal fin rays 10 (the last divided at base); pectoral fin rays 16, uppermost branched pectoral fin ray is the second; lacrimal with 2 spines over maxilla that point at nearly right angle from each other, the posterior pointing ventrally and slightly anteriorly; occipital pit well developed; anteriormost mandibular lateral-line pores small, separated; scales ctenoid; 59-62 scale rows in longitudinal series; scales absent on chest and pectoral fin base; and cirri developed over entire head and body, but no cirri on lower jaw. An updated checklist of the species of the genus Scorpaena Linnaeus, 1758 and a key to the species of the eastern Atlantic, Mediterranean Sea and Red Sea are presented.

1 The method employed by the Indian false vampire bat Megaderma lyra (body mass about 40 g) to detect and capture prey from the surface of an artificial pond in an outdoor enclosure was studied. Frogs (Rana tigerina) (body mass about 10 g) were used as prey. The bats exhibited searching flights at the surface of the water for a few minutes in darkness, detected a stationary frog with its head jutting out of the water, and with a dart captured the frog in the mouth after hovering over it for about 2 s. The detected frogs did not show any movement when the bats hovered over them. 2 When a freshly killed frog alone was available and pinned with its head protruding out of the surface of the water, the bats captured it after making fewer numbers of attempts in a shorter period of time compared with the capture of live frogs. The number of attempts and time taken to capture a frog increased when the frog's eyeballs alone were exposed above the water surface, and the bats failed to detect frogs when their entire head was submerged just below the water. 3 Sound and video recordings showed that M. lyra continuously emitted faint ultrasounds while making searching flights at the pond. Apparently the bats made ‘early’ and ‘late’ detections, with higher repetition rates of sound emission in the case of the latter. A final buzz before capturing prey was not recorded and the change in the duration of emitted sounds during approach and after capturing the frog was marginal. The second harmonic at 43.6 kHz (SD 3.5 kHz) was more dominant and the duration was 1.0 ms (SD 0.2 ms). 4 It is clear that M. lyra uses echolocation to detect and capture prey from the water surface. A comparison is made with an earlier report on M. lyra catching prey from the ground by a passive acoustic location.

116.The present study was aimed at testing a novel idea, that rather than maximizing theirdistance from a predator during close-distance encounters, prey species are better offmoving directly or diagonally toward the predator in order to increase the relative speedand confine the attack to a single available clashing point. We used two tamed barnowls Tyto alba to measure the rate of attack success in relation to the direction of preymovement. A dead mouse or chick was used to simulate the prey, pulled to variousdirections by means of a transparent string during the owl’s attack. Both owls showed ahigh success rate in catching stationary compared with moving food items (90% and21%, respectively). Success was higher when the prey moved directly away, rather thantowards the owls (50% and 18%, respectively). Strikingly, these owls had 0% success incatching food items that were pulled sideways. This failure to catch prey that movesideways may reflect constraints in postural head movements in aerial raptors thatcannot move the eyes but rather move the entire head in tracking prey. So far there isno evidence that defensive behavior in terrestrial prey species takes advantage of theabove escape directions to lower rates of predator success. However, birds seem toadjust their defensive tactics in the vertical domain by taking-off at a steep angle, thusmoving diagonally toward the direction of an approaching aerial predator. Thesepreliminary findings warrant further studies in barn owls and other predators, in bothfield and laboratory settings, to uncover fine predator head movements during hunting,the corresponding defensive behavior of the prey, and the adaptive significance of thesebehaviors.D. Eilam (correspondence) and E. Shifferman, Department of Zoology, Tel-AvivUniversity, Ramat-Aviv 69 978, Israel. E-mail: eilam@post.tau.ac.il

A 75-day study was conducted to determine the effect of starvation on classical and truss parameters in Rhynchocypris oxycephalus (Sauvage and Dabry). Truss dimensions of almost the entire head and trunk region as well as the abdomen were increased significantly through feeding or starvation (P

The aims of the present study were, first to develop a new method for evaluating sperm hyperactivation (HA) based on sperm head axis angle deviation, and second to apply this method in scoring selected sperm populations during capacitation. This was made possible by improving our original superimposed image analysis system (SIAS). The new option on the system enables us to determine the real angular deviation of the entire head in successive superimposed frames. The entire procedure for each spermatozoon requires 10-20 sec, according to the frame/rate utilized. A clear cut-off between the values of hyperactivated, transitional and non-hyperactivated spermatozoa was found at 11 and 21 frames/sec. However, at 6 frames/sec, a partial overlap between the three classes was found. We defined sperm activity as follows. At 11 frames/sec, hyperactivated: angle sumor = 405 degrees; transitional: 200 degreesor = angle sum405 degrees. At 21 frames/sec, hyperactivated: angle sumor = 760 degrees; transitional: 350 degreesor = angle sum760 degrees. The results, in agreement with previous research, show the peaks of activity at 3 h, dropping to a minimum at 6 h. This phenomenon was significantly more evident in fertile compared with subfertile semen samples.

Summary Geometric morphometries are a set of recently developed techniques in the study of biological forms. In this paper these techniques are used in the characterisation of shape changes of the cranial region during growth of the Adriatic sturgeon Acipenser naccarii. Species identification in sturgeons is sometimes difficult, biased by morphological plasticity, by individual variability, complicated by human intervention and manipulation, such as aquaculture, hybridisation, pollution and shape changes during growth (allometry). Characteristic changes in head morphology during subadult growth concern the relative shortening and the lateral stretching of the entire head region. These and other observed shape changes were never previously visualised nor reported in the literature. Geometric morphometries is proposed as a good candidate to became the universal methodology in the morphometrical analysis of sturgeons.

A pituitary adenoma was diagnosed via histopathologic examination in an aged female Dumeril's ground boa, Acrantophis dumerili. The snake exhibited postural abnormalities, dull mentation, and poor muscle tone prior to death. Pituitary neoplasms appear to occur very rarely in reptiles, but may be underreported if the pituitary gland is not routinely examined. This report illustrates the importance of submitting the brain or entire head for microscopic evaluation.

The myth of rachipagus twins is hereby exploded-the myth, not the rachipagus! In a review of over 1,200 cases of conjoined twins, one classic example of rachipagus was found-two complete infants with dorsal union of the entire head and trunk, with roentgenograms showing clearly visible bony union of the vertebral arches from T6 to L3. After the typical case was discovered, 20 dorsal parasitic twins were reevaluated and reclassified as rachipagus. Two had extensive vertebral fusion and 18 were united in the dorsal midline, all with a meningocele, vertebral anomaly, and/or bony or neural connection. A theory of the embryologic origin of these twins is proposed: two embryonic discs located on diametrically opposing aspects of a single amniotic cavity becoming united in the area of the closing neural folds. This again raises the controversy concerning "fission or fusion" in conjoined twins.

Phalotris is a genus of Neotropical snakes with secretive habits that is poorly represented in collections. We describe a new species of Phalotris belonging to the bilineatus group from near Filadelfia in the Dry Chaco of Paraguay. The new species differs from P. lemniscatus and P. spegazzinii by having wider white and black neck collars, a wider black transverse ring in the anal region, and different coloration of the black dorsolateral lines. It differs from P. multipunctatus in the presence of a caudal ring, wider white and black neck collars, and having the entire head black without white marks. In addition, the new species is the only member of the bilineatus group with the black ventral coloration reduced to scattered dots. The new species is described based on three road-killed specimens found since 1995. The new species is currently considered endemic to xerophytic areas of the Paraguayan Chaco. Five species of Phalotris are now known to occur in Paraguay.

Dissection of temportal bone is essential for training in otology. Human temporal bones, if for different reasons are not available, an animal model like Ram Head may be used for surgical dissection training of the temporal bones. In Ram model the entire head is used as head of removing the temporal bone. Ram Head is advantageous for its easy access and anatomical similarity with human temporal bones.

Non-visual responsiveness to photic stimulation was investigated in pigeon embryos (days 11½–17½ of incubation) and neonates (6–24 hours posthatch). At all ages observed, these animals exhibited a marked overt response to light onset, a response which occurred even when the entire head was occluded from light, but which could be blocked (in hatchlings) by covering all of the body except the head. It was therefore concluded that retinal or direct brain mediation did not underlie the response, but rather, some form of dermal sensitivity would best account for it. Chicken embryos (day 19 of incubation) and Ring dove hatchlings (12–24 hours posthatch) were similarly investigated. Although there was evidence in both of these species for light-contingent motility, their responsiveness was seemingly mediated by either visual or direct brain stimulation, since occlusion of the head eliminated the effect. Thus, of the three species tested, only the pigeon appeared to possess the non-visual dermal light sensitivity. Possible significance of this responsiveness for this species was discussed.

The functional and structural aspects of the suspensorium of Ctenopoma acutirostre have been correlated with those of Anabas testudineus. The different parts of the suspensorium are described, as are the muscles that are functionally connected with the suspensorium. Functions were analyzed by observations on living specimens, and by measurements recorded from the movie films. The role played by various bones and muscles to carry out the functions (the respiration, the gulping, and the feeding) has been explained. The different bones and muscles have been considered as functional units which often are connected to form couplings. During the respiration in Ctenopoma the depression of the lower jaw is conducted by the levator operculiopercular apparatus-mandible coupling. The presence of this coupling is indicated by the presence of dorso-ventral movement of the operculum. A remarkable ventro-dorsal and antero-caudal movement in the urhyal during feeding shows in Ctenopoma the presence of the sternohyoideus-hyoid apparatus-interopercular-mandible coupling, which depresses the lower jaw. In Ctenopoma, the suspensorium takes part in respiration, gulping, and feeding, whereas in Anabas it is only involved in gulping and feeding. To carry out its functions, the suspensorium implies three articulations: palatocranial, craniohyomandibular, and quadratomandibular with the cranium and the lower jaw, respectively. Finally, the suspensorium has been analyzed as a part of the architectonic structure of the entire head by using a diagrammatic model (fig. 13) based on mutual influence, integration, and couplings.

An anti-sperm monoclonal antibody was developed from female C57BL/6 mice immunized with epididymal sperm from a syngeneic male mouse. Immunofluorescence staining revealed that the antibody did not react to fresh epididymal sperm but attached to the capacitated sperm found in the peri-vitelline spaces of the ova. When the antibody was applied to sperm incubated in vitro, variously stained sperm were observed. It was presumed that the antigenic site detected by the antibody was hidden in the fresh epididymal sperm and was spread from the acrosomal cap region to the entire head during the capacitation process.

A method was developed to determine the net heat gain per unit of time (G) in a mature, growing head of lettuce (Lactuca sativa L., var. capitata from measured temperatures, by adapting a formula used to calculate internal energy changes in columns of air, water, or soil ( Sellers , 1965). G also was calculated for hypothetical cubes (sides 1 cm), one of which represented the cool side of the head, and the other the warm side, and each having a thermocouple at its center. The mean for the two cubes differs from that for the entire head by less than 10%, and avoids the cumbersome determination of the mean temperature of the head. Tipburn of lettuce was discussed in relation to internal differences in G.

The plasmalemma of the mammalian spermatozoon contains a number of specific proteins, some of which have a clear regional distribution (see ref. 1–5). It is reasonable to assume that one or more sperm membrane proteins are involved in the initial recognition events of fertilization. We have isolated a number of boar sperm membrane glycoproteins and in this communication two of them will be described in some detail.