Ovoid Eggs Research Articles

REVISION OF SANGUINICOLA PLEHN, 1905 WITH REDESCRIPTION OF SANGUINICOLA VOLGENSIS (RAŠÍN, 1929) MCINTOSH, 1934, DESCRIPTION OF A NEW SPECIES, PROPOSAL OF A NEW GENUS, AND PHYLOGENETIC ANALYSIS.

Sanguinicola Plehn, 1905 comprises 26 species that collectively infect fishes from 8 orders (Cypriniformes, Characiformes, Siluriformes, Esociformes, Salmoniformes, Labriformes, Centrarchiformes, and Perciformes). Its revision is warranted because several species assigned to the genus could represent new genera, nucleotide sequences are wanting, many species have incomplete descriptions, and types for most species are missing or of poor quality. Herein, we emend Sanguinicola based on morphology and the first nucleotide-based phylogenetic analysis that includes multiple sequences from morphologically identified adult specimens. We describe Sanguinicola plehnae Warren and Bullard n. sp. from the heart of northern pike, Esox lucius Linnaeus, 1758 from Russia; provide supplemental observations of Sanguinicola volgensis (Rašín, 1929) McIntosh, 1934 from the heart of sabrefish (type species), Pelecus cultratus (Linnaeus, 1758) Berg, 1949 from Russia; describe Sanguinicola cf. volgensis from the heart of ide, Leuciscus idus (Linnaeus, 1758) Berg, 1949 from Russia; and describe Pseudosanguinicola occidentalis (Van Cleave and Mueller, 1932) Warren and Bullard n. gen., n. comb. from the heart of walleye, Sander vitreus (Mitchill, 1818) Bailey, Latta, and Smith, 2004 from eastern North America. Sanguinicola plehnae differs from its congeners by having lateral tegumental spines that total 118-122, are small (3% of body width), and protrude 2-3 µm from the tegument (lacking associated conical protrusion) as well as by having a large testis (>40% of body length). Sanguinicola volgensis differs from its congeners by having posteriorly directed lateral tegumental spines encased in a tegumental conical protrusion as well as by having an ovoid egg. Specimens of S. cf. volgensis differ from those of S. volgensis by having a body that is 5-6× longer than wide (vs. 2-3× in S. volgensis) and <90 lateral tegumental spines (vs. >95). Pseudosanguinicola Warren and Bullard n. gen. differs from Sanguinicola by having densely transverse rows of lateral tegumental spines (vs. a single column of large spines). The phylogenetic analysis utilizing the large subunit ribosomal DNA (28S) failed to reject monophyly of Sanguinicola.

Egg Quality of Italian Local Chicken Breeds: I. Yield Performance and Physical Characteristics.

The aim of this study was to compare yield performance (from 39 to 50 weeks of age) and egg physical characteristics (at 50 weeks of age) of eight autochthonous chicken breeds of the Veneto region (Italy). Four white eggshell breeds, namely Padovana Camosciata (PA-C, chamois plumage), Padovana Dorata (PA-G, golden plumage), Polverara Bianca (PO-W, white plumage), and Polverara Nera (PO-B, black plumage), and four tinted eggshell breeds, namely Pepoi (PP), Ermellinata di Rovigo (ER), Robusta Maculata (RM), and Robusta Lionata (RL) from a conservation centre were considered in the trial. Significant differences (p < 0.05) among breeds were observed for yield performance and egg quality. From 39 to 50 weeks of age, the hen-day egg production was higher in PA-C and RM than in RL, and PO-W and ER were intermediate; PA-G, PO-B, and PP were the lowest. The hen-day egg production changed according to the age of the hens. From 39 to 42 weeks of age, ER showed the highest hen-day egg production and PA-G the lowest; from 47 to 50 weeks, PA-C, PO-W, and RM were the highest and PP the lowest. The tinted eggshell breeds, with the exception of PP, had higher egg weights than white eggshell breeds. PP egg weight was similar to PO-B. As regards the tinted eggshell breeds, RM eggs had the highest eggshell a* and b*, and PP the lowest. PA-C had the most spherical eggs, and PO-B and ER had the most ovoid eggs. PO-W and RM had the highest eggshell thickness and ER had the lowest. The highest eggshell ratio was observed for PO-W and PO-B, and the lowest for ER. The yolk-to-albumen ratio was higher in the white eggshell breeds than in PP, ER, and RL. ER had the highest Haugh units and PA-G the lowest. PO-W, PO-B, PA-C, PA-G, and ER had the lowest egg inclusions, and RL and RM the highest. Tinted eggshell eggs differed from white eggshell eggs by having higher meat spots. Results indicated that the eggs produced by the eight local chicken breeds differed according to the laying rate and a wide range of physical external and internal characteristics which allow the consumer to distinguish them for their genetic origin by the eggshell shape and colour, and to use them for different purposes to valorise poultry biodiversity.

RESOLVING THE PARAPHYLETIC TURTLE BLOOD FLUKES: REVISION OF SPIRORCHIIDAE STUNKARD, 1921 AND PROPOSAL OF CARETTACOLIDAE YAMAGUTI, 1958, HAPALOTREMATIDAE (STUNKARD, 1921) POCHE, 1926, BARACKTREMATIDAE N. FAM., PLATTIDAE N. FAM., AND ATAMATAMIDAE N. FAM.

Turtle blood flukes ("spirorchiids") comprise a paraphyletic assemblage including the monophyletic Schistosomatidae Stiles and Hassall, 1898 as a crown group. We herein morphologically diagnose the natural groups of turtle blood flukes and propose family names for them. Spirorchiidae Stunkard, 1921 (Spirorchis MacCallum, 1919 [type]; Spirhapalum Ejsmont, 1927; Plasmiorchis Mehra, 1934; MonticelliusMehra, 1939; VasotremaStunkard, 1928; provisionally UterotremaPlatt and Pichelin, 1994) has a ventral sucker (lost in Spirorchis), an esophageal gland surrounding the entire esophagus, lateral esophageal diverticula (plicate organ and medial esophageal diverticulum present or absent), a glandular mass at the esophagus base, paired ceca surrounded by vitelline follicles for their entire length, a non-filamented, ovoid egg, and typically a Manter's organ. Baracktrematidae n. fam. (Baracktrema Roberts, Platt, and Bullard, 2016 [type]; Unicaecum Stunkard, 1925; NeospirorchisPrice, 1934) has no ventral sucker, a single cecum or cyclocoel, a coiled or looped testis extending into the anterior body half, a convoluted post-cecal and post-gonadal uterus, a uterine pouch, no metraterm, no Manter's organ, and non-filamented eggs. Plattidae n. fam. (Platt Roberts and Bullard, 2018 [type]; Hapalorhynchus Stunkard, 1922; Coeuritrema Mehra, 1933; Enterohaematotrema Mehra, 1940; CardiotremaDwivedi, 1967; Ruavermis Dutton and Bullard, 2020) has the anatomical sequence of a ventral sucker, external seminal vesicle, cirrus sac, anterior testis, ovary, transverse vitelline duct, and posterior testis (except Enterohaematotrema) plus a pars prostatica, dorsal genital pore, globular excretory vesicle, and no Manter's organ. Carettacolidae Yamaguti, 1958 (CarettacolaManter and Larson, 1950 [type]) has a spinose oral sucker, a spinose and contractile ventral sucker (transverse cavity present), numerous testes distributing in a post-ovarian, inter-cecal column, and an ovary and transverse vitelline duct that are pre-testicular. Hapalotrematidae (Stunkard, 1921) Poche, 1926 (Hapalotrema Loos, 1899 [type]; AmphiorchisPrice, 1934; LearediusPrice, 1934; Cheloneotrema Simha and Chattopadhyaya, 1980; NeocaballerotremaSimha, 1977; Satyanarayanotrema Simha and Chattopadhyaya, 1980; Shobanotrema Simha and Chattopadhyaya, 1980) has the anatomical sequence of a ventral sucker, anterior testis(es), external seminal vesicle and cirrus sac, ovary, and posterior testis(es). Atamatamidae n. fam. (Atamatam Bullard and Roberts, 2019 [type]; Paratamatam Bullard and Roberts, 2019; Pitiutrema Dutton and Bullard, 2019) has an oral sucker with anteroventral spines, vasa efferentia connecting to a pre-ovarian external seminal vesicle, a cirrus sac directed postero-laterad and having an internal seminal vesicle and glandular luminal wall, and a dendritic ovary flanked by the external seminal vesicle and oviducal seminal receptacle. A 28S phylogenetic analysis failed to reject the monophyly of these families.

Discrete aggregate analysis of ovoid egg shapes in various bird species

The shape from 16,491 eggs of 472 species of 19 groups of birds was studied. The analysis was carried out by photographing eggs using a specially written software. In parallel, profiles of different ovoids were built in the CorelDRAW software, by articulating circles of different diameters. Comparison of them with the profiles of real bird eggs showed complete identity. During further analysis, we found that the whole variety of shapes fits into a system of discrete aggregates described by the proportions: (a) ±√a±√b)/±√c: (a) ±√2±√1)/±√4 = (0.207; 1.207); (b) ±√3±√1)/±√4 = (0.366; 1.366); (c) ±√4±√1)/±√4 = (0.5; 1.5); (e) ±√5±√1)/±√4 = (0.618; 1.618). These proportions are universal constants of nature, similar to π and e (the base of the natural logarithm). Besides them, we realize another constant in eggs. This is the cross-ratio (or the double ratio or the wurf. The close connection between the shapes of bird eggs and the universal constants of nature allows us to solve the following problems. We therefore suggested that discussed patterns of the geometric model and the resulting form standards will contribute to the unification of egg analysis methods. We also believed that the suggested universal model and constants will resolve the question of quantitative expression of the optimal shape and incubation qualities of eggs.

Mathematical progression of avian egg shape with associated area and volume determinations

Development of nondestructive techniques for estimating egg parameters requires a comprehensive approach based on mathematical theory. Basic properties used to solve theoretical and applied problems in this respect are volume (V) and surface area (S). There are respective formulae for calculating V and S of spherical, ellipsoidal, and ovoid eggs in classical egg geometry; however, the mathematical description and calculation of these parameters for pyriform eggs have remained elusive. In the present study, we derived the appropriate formulae and established that this would be not only applicable and valid for the category of pyriform eggs, but also universal and explicit for all other naturally occurring avian egg shapes. Thus, we have demonstrated “mathematical progression” of this natural object, considering the egg as a sequence of geometric figures that transform from one to another in the following sequence of shapes: sphere → ellipsoid → ovoid (whose profile corresponds to Hügelschäffer's model) → pyriform ovoid.

The Eggs of the Bradyporus (Callimenus) dilatatus (Stål, 1875) (Orthoptera, Tettigoniidae): Morphological, Histological and Ultrastructural Study

The aim of this study is to reveal the fine structure and morphology of the eggs of Bradyporus (Callimenus) dilatatus (Stål, 1875) (Orthoptera, Tettigoniidae) by using stereomicroscopy, light microscopy and scanning electron microscopy (SEM). B. dilatatus females produce generally bilateral symmetrical, elongated ovoid eggs. The chorion is composed of three layers named as endochorion, exochorion and extrachorion. Cross sections of all three layers show the chorion has air chambers that connected to each other with canals. The extrachorion layer forms hexagonal or pentagonal surface patterns which is typical to B. dilatatus. The lengths of the boundaries of polygonal patterns become longer with aging.

Evaluación de la calidad del huevo marrón comercial del cantón La Troncal, Ecuador

Se evaluó la calidad del huevo marrón comercial del cantón La Troncal, Ecuador. Se estudiaron un total de 1200 huevos (parroquia La Troncal, 400 huevos; parroquia Manuel J. Calle, 400 huevos y parroquia Pancho Negro, 400 huevos). Se realizó el análisis físico externo que incluye peso de huevo, espesor y peso de cáscara, y el análisis físico interno, que incluye diámetro, y altura de clara y de yema. Se clasificaron los huevos según color, peso y forma. Cada parroquia se consideró un tratamiento y las medias de las variables del análisis físico externo y del interno, fueron separadas utilizando la prueba de Tukey (p≤0.05). Los colores 90, 100 y 110, fueron los más frecuentes. Según el peso del huevo, las categorías más frecuentes fueron extragrande (38%), grande (30%) y gigante (19%). Según la forma, la mayor frecuencia fue de huevos ovoides y redondos (92%), siendo más frecuentes, entre estas dos categorías, los huevos ovoides. Las aves de la parroquia Manuel J. Calle produjeron (p≤0.05) huevos más grandes, con mayor diámetro y altura de clara, con mayor altura de yema, con mayor peso y espesor de cáscara, color marrón más obscuro y principalmente huevos ovoides, mientras que las demás parroquias produjeron valores levemente inferiores. En conclusión, las parroquias de La Troncal, Ecuador, producen huevos grandes, con buen diámetro y altura de clara, y color francamente marrón, es decir producen huevos de muy buena calidad.

Endemic Dragons of Sumatra's Volcanoes: New Species ofDendragama(Squamata: Agamidae) and Status ofSalea rosaceumThominot

Abstract: We discovered new populations of Dendragama at the northern and southern ends of Sumatra. High genetic distances and concordance of multiple, apparently independent diagnostic characters support our descriptions of these two populations as new species. We define new characters of the sublabial, tympanic, dorsal crest, and dorsolateral crest scales. The three species of Dendragama undergo remarkable color change in response to time of day and stress. Females lay 2–4 ovoid eggs, reach sexual maturity at about 60 mm snout–vent length, and likely produce multiple clutches each year. We remove Salea rosaceum Thominot from the synonymy of Dendragama boulengeri and argue that the unique holotype of S. rosaceum is a specimen of Pseudocalotes tympanistriga with incorrect locality information.

Paleoecological implications of two closely associated egg types from the Upper Cretaceous St. Mary River Formation, Montana

Two closely associated egg types occur at the same locality in the Upper Cretaceous (Maastrichtian) St. Mary River Formation in north central Montana. These specimens represent the first fossil eggs described from this formation. At least fifteen small ovoid eggs or egg portions are scattered through a 25 cm interval of rock. Five significantly larger, round eggs overlie these smaller eggs and are in close proximity to one another on a single bedding plane. The best preserved egg of the smaller size measures 36 mm × 62 mm and exhibits the prismatic, two-layered eggshell structure of a theropod egg. The dispersed distribution and inconsistent angles of these small eggs likely resulted from disturbance by subsequent nesting activity and/or possibly nest predation. At least twelve additional small prismatic eggs also occur at this site. We assign the small eggs as a new oogenus and oospecies, Tetonoolithus nelsoni, within the Prismatoolithidae. The large round eggs measure 130 mm in diameter and the eggshell displays substantial diagenetic alteration. These eggs likely belonged to a hadrosaur due to their similarity in egg size, shape, and eggshell thickness to Maiasaura eggs from the stratigraphically lower Two Medicine Formation. Eggs at different stratigraphic levels at this site indicate that conditions favorable to both dinosaur species persisted for an extended period of time. However, determining whether these dinosaurs occupied the nesting site at the same or different years remains beyond the resolution of the rock record.

The biology of Placostylus ambagiosus (Pulmonata: Bulimulidae) in New Zealand: Part 1. Behaviour, habitat use, abundance, site fidelity, homing and the dimensions of eggs and snails

The large land snail Placostylus ambagiosus (Pulmonata: Bulimulidae) was investigated during a long-term study in northernmost New Zealand. The snails fed at night on fallen leaves from a variety of broadleaf trees and bushes. During the day, most snails in shrubland rested under plants close to their food sources at densities of up to 53 snails per m2 and mean live biomasses of 47–72 g/m2. Individual snails stayed close to their food plants for up to 12 years, seldom moving away. Resting behaviour and site fidelity in forest was not investigated in detail, but some adult snails in forest returned to their original sites after being moved up to 60 m into a fenced area built to protect them from feral domestic animals. The ovoid eggs (mean 7.0 mm long×5.6 mm wide; ranges 5.5–7.7 mm long; 5.1–6.7 mm wide) were laid in clutches averaging 43 eggs (range 1–113 eggs) in shallow cavities covered with soil. More than one snail may contribute to a clutch. Adult shell height ranged from 43 mm to 97 mm and varied with habitat quality. Where snail abundance was high adults were small. Implications of these results for conservation management are discussed.

Anserobilharzia gen. n. (Digenea, Schistosomatidae) and redescription of A. brantae (Farr & Blankemeyer, 1956) comb. n. (syn. Trichobilharzia brantae), a parasite of geese (Anseriformes).

A new genus, Anserobilharzia, is proposed to accommodate Anserobilharzia brantae n. comb. (syn. Trichobilharzia bran- tae Farr & Blankemeyer, 1956), a species of avian schistosome thus far found exclusively in anserini geese (Anser, Branta, Chen) from Europe and North America, and Gyraulus snails. Recent collections and subsequent molecular analyses showed that A. brantae was distinct from Allobilharzia and Trichobilharzia and grouped basal to Trichobilharzia. Using nuclear 28S, ITS and mitochondrial cox1 as genetic yardsticks, samples of A. brantae from North America and Europe were each other's closest relative and distinct from Allobilharzia and Trichobilharzia. Anserobilharzia brantae was also distinct when compared morphologically with other species of closely related avian schistosomes. The following descrip- tion is based on males, females, eggs, and cercariae. The new genus is characterized by a) ovoid egg (72-145µm x 44- 89 µm) with spine, b) male with > 500 testes and caecal reunion anteriad to seminal vesicle, c) cercariae with 5+1 flame cells, and d) intermediate hosts are planorbid snails. The only confirmed species of snail host is Gyraulus parvus in North America. Based on presented data, we propose a new genus and new combination for A. brantae justified by morpholog- ical, host use, and molecular characteristics.

Eggs of the Blind Snake,Liotyphlops albirostris, Are Incubated in a Nest of the Lower Fungus-Growing Ant, Apterostigmacf.goniodes

Parental care is rare in most lower vertebrates. By selecting optimal oviposition sites, however, mothers can realize some benefits often associated with parental care. We found three ovoid reptilian eggs within a mature nest of a relatively basal fungus-growing ant,Apterostigmacf.goniodes(Attini), in central Panama. In laboratory colonies,A.cf.goniodesworkers attended and cared for the eggs. Two blind snakes,Liotyphlops albirostris(Anomalepididae), successfully hatched, which is the first rearing record for this species. The ants did not disturb the snakes, and the snakes did not eat the ants; we found no ants in the dissected stomachs of the snakes. We review other associations between nesting fungus-growing ants and egg-laying vertebrates, which together suggest that attine nests may provide a safe, environmentally buffered location for oviposition, even in basal attine taxa with relatively small colony sizes.

Aspects of the biology and ecology of the Orange-Bellied Crayfish,Euastacus mirangudjinCoughran 2002, from northeastern New South Wales.

The biology of Euastacus mirangudjin, a small freshwater crayfish from subtropical eastern Australia, is described for the first time. Long-term monitoring was undertaken at a site in Toonumbar National Park to gather data on growth, moulting, maturity and reproductive activity. To complement field observations, egg and juvenile development was further studied in laboratory aquaria. The orangebellied crayfish reaches less than 40 mm carapace length, with female maturity occurring near 30 mm. Animals do not respond to baits, and appear to spend most of their time within their burrows. The species is an Autumn-Spring brooder with a distinctly low fecundity and large, ovoid eggs (3.0 x 3.8 mm), and females do not appear to routinely moult prior to spawning. At some sites, the species co-occurs with the much larger and spinier E. sulcatus. A high incidence of regenerate chelipeds, missing limbs and other wounds was recorded. Euastacus mirangudjin hosts a small, unpigmented Temnocephalan flatworm. The biology and ecology of the species is discussed with reference to other species in the genus Euastacus.

Morphology of Eogystia sibirica (Alphéraky) (Lepidoptera: Cossidae) attacking Asparagus officinalis in northern China with descriptions of its immature stages

The carpenter moth Eogystia sibirica (Alphéraky) (Lepidoptera: Cossidae) is a serious pest of the garden asparagus Asparagus officinalis (family Liliaceae) in northern China, with its larvae boring in the stem and roots, frequently causing significant damage to the plant. All the life stages of the pest, including egg, larva, pupa and adult, are described and illustrated in detail. The ovoid egg is covered with a reticulate meshwork of ridges on the chorion. The eruciform larva possesses only three stemmata on each side of the head; the reduced abdominal prolegs on segments III–VI each bear 35–55 uniordinal crochets arranged in two transverse bands; the short anal prolegs each bear five to seven uniordinal crochets in a transverse band. The pupa is adecticous and obtect, without cremaster. The reduction of larval stemmata and the invagination of the adult pterosterna are briefly discussed.

Egg Morphology of the Predatory mite, Cheyletus malaccensis (Acarina: Cheyletidae)

The external egg morphology of the predatory mite Cheyletus malaccensis Oudemans 1903 was studied. It was found that the eggs have two shape forms. The freshly laid egg is regularly ellipsoid (133 x 94 μm), but its shape changes to ovoid (143 x 96 μm) approximately in the middle of its development. The formation of the ovoid egg shape is connected with the appearance of a special microstructure, which perforates the egg surface on the top of the broader end of the egg. The duration of both egg forms depends on the temperature conditions. Morphological details of eggshells are illustrated with scanning electron microscope (SEM) micrographs.

An Exploratory Fishing Survey and Biological Resource Assessment of Atlantic Hagfish (Myxine glutinosa) Occurring on the Southwest Slope of the Newfoundland Grand Bank

An exploratory Atlantic hagfish (Myxine glutinosa) survey was conducted on the southwest slope of the Newfoundland Grand Bank during autumn 2002 to collect samples for a biological resource assessment and investigate the selective properties of baited 227-litre traps with 12.7, 13.5, and 14.3 mm (1/2, 17/32, and 9/16) diameter escape holes. Atlantic hagfish were found to exhibit a juvenile hermaphroditic stage. Female Atlantic hagfish exhibited a total length (TL) at first, 50%, and 100% sexual maturity of 354, 378, and 440 mm, respectively. The testis was small and rudimentary showing no sign of maturation in the form of enlarged lobules in 350 hagfish examined within a size range of 195–638 mm TL. Each sexually mature female possessed a single clutch of developing ovoid eggs of similar size and 28% possessed both developing and degenerating eggs. Degenerating eggs were limited to the early stage of the reproductive cycle among females with developing eggs that were <12 mm in length. Examination of females with large (≥14 mm) eggs revealed a positive correlation (r2 = 0.61) between fecundity and total body length, however, the reproductive potential was low (11–38 eggs per female). Recent evidence of a seasonal reproductive cycle and current findings of a bimodal egg length-frequency distribution and the presence of several females with postovulatory follicles in a single point in time sample suggest there may be up to three synchronized spawning events per year on the Grand Bank. The intermediate status of the Grand Bank population with respect to maximum length, size at first attainment of sexual maturity, and body markings relative to populations in the eastern North Atlantic and continental shelf and slope waters of the eastern US corroborates the existence of clinal variants. Catches in control traps indicate a clear tendency for the average individual hagfish body size to increase with depth over a 146–664 m depth range. A length-weight relationship indicated the minimum marketable body weight coincides with a total length of 410 mm. The 14.3 mm trap consistently captured the lowest percentage of undersized (<410 mm TL) individuals. Studies suggest few hagfish will survive when released, therefore it is recommended Grand Bank fishermen be encouraged to use traps with 14.3 mm escape holes or larger.

New Thelastomatoidea (Nematoda: Oxyurida) from Australian burrowing cockroaches (Blaberidae: Geoscapheinae, Panesthiinae)

AbstractFour new species and two new genera of thelastomatoid are described from several species of Australian burrowing cockroaches (Blattodea: Panesthiinae; Geoscapheinae). Corpicracens munozae n. g., n. sp., Pseudodesmicola botti n. g., n. sp. and Cephalobellus nolani n. sp. are described from Geoscapheus dilatatus (Blattodea: Geoscapheinae) from Mendooran, New South Wales; one new thelastomatid, Blattophila praelongicauda n. sp., is described from Panesthia cribrata from Lamington National Park, Queensland. Corpicracens munozae n. g., n. sp. is long and slender, with a monodelphic female reproductive system, a clavate corpus with a slight posterior pseudobulb, oval eggs flattened at the poles, and a relatively robust, subulate tail. Pseudodesmicola botti n. g., n. sp. is slightly more robust in body, also has a monodelphic reproductive system, a cylindrical corpus with a posterior pseudobulb, ovoid eggs and a very long, subulate tail. Cephalobellus nolani n. sp. is distinguished from other members of the genus by its relatively short and broad body and egg shape. Lastly, Blattophila praelongicauda n. sp. is distinguished from other members of the genus by having eggs with a single, polar operculum, tail length, and position of the vulva, nerve ring and excretory pore. An additional species, known by a single specimen from Panesthia tryoni tryoni from the same locality is characterised but not named. The species found are all relatively rare parasites of Australian burrowing cockroaches, each having a prevalence of less than 10%.

Sanguinicola maritimus n. sp. (Digenea: Sanguinicolidae) from Labridae (Teleostei: Perciformes) of southern Australian waters

A new species of Sanguinicola Plehn, 1905 is described from the marine teleosts Notolabrus parilus (Richardson) and N. tetricus (Richardson) (Perciformes: Labridae) from Western Australian and Tasmanian waters. This host distribution is strikingly anomalous; however, the present material fulfils the morphological criteria of Sanguinicola. S. maritimus n. sp. differs from previously described species in having the combination of a body 1,432--1,701 mum long, the oesophagus 18.3--21.7% of the body length, the testis occupying 42.8--52.3% of the body length, an oviducal seminal receptacle and Mehlis' gland present, ovoid eggs, and vitelline follicles that extend anteriorly past the nerve commissure, laterally past the lateral nerve chords and posteriorly to the anterior margin of the cirrus-sac. S. maritimus also lacks a protrusible anterior proboscis. It also differs in the combination of host and geographical location, being the first Sanguinicola species from a marine teleost and the first from Australian waters.

The Life Histories of the Offshore Oedicerotids Westwoodilla Caecula and Monoculodes Packardi (Crustacea: Amphipoda) From Loch Fyne, Scotland

Results are presented of a comparative study on seasonal variations in population density, population structure and reproductive bionomics of two species of offshore benthic oedicerotid amphipod, Westwoodilla caecula (from 35 m depth) and Monoculodes packardi (from 190 m) in Loch Fyne (Scotland). Observations on live coloration and behaviour of these species in laboratory aquaria are also included. Male W. caecula were, on average, smaller than females. In M. packardi (atypically among Oedicerotidae) the reverse was true. Population densities of both species, calculated from sledge net tows (1-mm mesh), fluctuated erratically over one year (1992). Ovigerous W, caecula were recorded virtually year-round, but were commonest from midsummer to early autumn. Ovigerous M. packardi were noted in spring and early autumn. Monoculodes packardi had a semi-annual life cycle, but the pattern for W. caecula was less clear. The two generations of M. packardi grew at broadly similar rates, presumably associated with the damped seasonal fluctuations in physical environmental factors at 190 m. Female W. caecula possibly moult eight or nine times, and may produce three successive broods in a lifetime (M. packardi may only produce two). A positive correlation was found between fecundity (stage I eggs) and body length in W. caecula but, although a similar trend was apparent in the data for M. packardi, relevant data were too few for significance to be achieved. Ovoid eggs increased in volume by ×2 from stage I-IV in W. caecula, or ×1·5 from stage I–III in M. packardi. Brood sizes were much smaller in W. caecula than in M. packardi, although apparent brood mortality was higher in the latter. There was no significant relationship between the proportion of ovigerous females in the populations of either species and seasonal variation in physical environmental factors considered (temperature, salinity, daylength).

Reproductive cycling and fecundity estimation in the upland bully

The upland bully is a prolific and widespread member of New Zealand freshwater fish communities that may mature at age 1 (or earlier). It begins spawning in spring, laying as many as eight clutches of eggs over the spring and summer, at periods as brief as 13 days. Ovaries contain two modes of maturing oocytes, so that oogenesis must be continual during the spawning season. This poses difficulties in fecundity estimation, which were solved by captive rearing. The ovoid eggs are about 2 mm long; egg size declines with clutch number during the summer, but increases with fish size. Clutch size varied, in 70 spawnings, from 121 to 880 eggs, with total seasonal fecundity up to >5000 eggs. The production of multiple clutches greatly increases seasonal fecundity and may explain the success of this species in sometimes unreliable or harsh environments.