The Male Reproductive System and Spermatophore Formation in Pagurus novae-zealandiae (Dana) (Anomura: Paguridea)

Summary

An account is given of the anatomy and histology of the vas deferens and of spermatophore development. The vas deferens differs from that of other pagurids except P. timidus in having only one of the usual two opposed coils/spirals between which fragmentation of the continuous sperm sheath into discrete capsules occurs. The functions of these two regions occur within the single coil in P. novae-zealandiae, including capsule formation which is a result of muscular activity rather than of change in curvature of the vas deferens. Functional regions of the vas deferens are compared with those known for other members of the genus. Spermatophores are released in groups of 2–14 attached to a common pedestal. Each spermatophore has the capsule sheath elongated basally to form a stalk elevating it above the pedestal and is regarded as pedunculate. This condition is discussed in relation to other hermit crabs.     

Female internal reproductive organs,modes of sperm transfer,and phylogeny of Asian Epilachninae (Coleoptera: Coccinellidae)

A total of 22 Indonesian and Japanese species of epilachnine ladybird beetles were divided into the following three groups on the basis of the conditions of bursa copulatrix and spermatheca, and modes of sperm transfer. Group 1, ‘Henosepilachna’, being characterized by a spermatheca derived from the lateral side of a well developed bursa copulatrix and formation of a ‘spermatophore’ prior to ejaculation; group 2, Epilachna admirabilis species-group and E. chapini group, by a spermatheca derived from terminal end of a well developed bursa copulatrix and lack of spermatophore formation; and group 3, E. flavicollis group and E. fallax group, by a reduced bursa copulatrix with or without a terminally positioned spermatheca and lack of spermatophore formation. It was suggested that groups 2 and 3 are phylogenetically more closely related to each other than they are to group 1.     

Three new species of Pseudohaliotrema Yamaguti, 1953 (Monogenea: Ancyrocephalidae) from Siganus species (Siganidae) and the description of a mechanism for cross-insemination

Three new species of Pseudohaliotrema Yamaguti, 1953 were collected from two Siganus species caught off Singapore. They are Pseudohaliotrema virgata n. sp. and P. molnari n. sp. from Siganus virgatus and P. falcata n. sp. from S. guttatus. They differ in the shape and size of both the body and haptoral sclerites and in the morphology of the male organ (modified copulatory organ). Pseudohaliotrema species from siganids are characterized by having a large prominent vaginal pouch, an eversible spermatophore transfer tube associated with the vaginal pouch, ovoid spermatophores (in mature worms), a male organ adapted for spermatophore formation, a large prostatic reservoir, and a testis and ovary arranged side by side. Pseudohaliotrema plectocirra Paperna, 1972 is re-assigned as Tetrancistrum plectocirra (Paperna, 1972) n. comb. Pseudohaliotrema species from non-siganid fish do not possess these characteristics and belong elsewhere. The generic diagnosis of Pseudohaliotrema is amended. Pseudohaliotrema species use a spermatophore for sperm transfer, which is documented in detail for P. virgata n. sp. The same reproductive strategy is used by P. molnari n. sp. and P. falcata n. sp., as indicated by the presence of spermatophores on the spermatophore transfer tube and inside the vaginal pouch. The presence of individuals exchanging spermatophores indicates that P. sphincteroporus Yamaguti, 1953 and P. sigani Yamaguti, 1953 also employ the same mechanism. The spermatophore, assembled in the sclerotized male organ and stored in the spermatophore chamber, is retrieved by the eversible spermatophore transfer tube (housed within the vaginal pouch) and drawn into the vaginal pouch as the spermatophore transfer tube invaginates. Within the vaginal pouch, the wall of the spermatophore disintegrates releasing spermatozoa.     

Courtship,copulation and oviposition in the chalcedon checkerspot,Euphydryas chalcedona (Lepidoptera: Nymphalidae)

In this report we describe some aspects of the reproductive biology of a population of the chalcedon checkerspot, Euphydryas chalcedona, in central Arizona. Successful courtship in this species lasts about a minute and has a form similar to that of other nymphalids. During copulation the male forms a spermatophore within the female's bursa copulatrix that represents about 7% of the male's body weight. After copulation females may remate and older females may have mated as many as three times. The spermatophore deflates as time since deposition passes. Females oviposit every other day on average and lay their eggs in clusters. These data confirm previous brief reports of courtship structure and spermatophore size for E. chalcedona. Questions are raised about the control of receptivity in this species and the function of the mating plug.     

Mating behaviour and spermatophore transfer in the shrimp Heptacarpus pictus (Stimpson) (Decapoda: Caridea: Hippolytidae)

Summary

Heptacarpus pictus, a small caridean shrimp inhabiting the low intertidal of southern and Baja California, breeds during the winter, spring, and summer months. Fall is a period of growth. Life span of an individual does not exceed 18 months, with fish predation as the most likely source of mortality.

Females are multiple brooders, carrying developing embryos concomitant with increase in ovary size. Hatching of larvae is followed by a moult, after which the female is attractive to males and receptive to copulation. A distance pheromone does not appear to be involved in attraction of males to females. Males apparently respond to a non-diffusible substance on the exoskeleton of newly moulted females.

Precopulatory behaviour is absent. Copulation can be divided into a series of relatively stereotyped events. Female rejection of the male or his spermatophore is the chief cause of unsuccessful matings.

Males deposit the spermatophore on the underside of the female's first abdominal segment. Sperm packets are formed upon extrusion from the male's genital openings, and are composed of a mucoid material in which sperm are mixed. The glutinous spermatophores adhere to the female's smooth abdominal sternite.

The endopods of pleopods 1 and 2 of the male are different in shape, size and setation from homologous rami of females and juveniles. Endopods of pleopod 1 possess a distally located appendix interna, absent in juveniles and females. An anteriorly projecting process, the appendix masculina, is located on the endopod of pleopod 2 in males. Experiments were performed which showed that these modifications insure proper deposition of spermatophores. Males which had the copulatory rami removed did not transfer spermatophores as successfully as normal males.

Transfer of the spermatophore from the male to the female is a result of the interplay of male pleopods 1 and 2 during copulation. The large expanded abdominal pleurae of females prevent the male's genital opening from contacting her abdominal sternite. Thus, the male's anterior pleopods have become modified to lift the emitted spermatophore from his genital orifices to the first abdominal sternite of the female.     

Four new earthworms of the genus Amynthas (Oligochaeta: Megascolecidae) from Mount Emei,Sichuan Province,China

Four new species were collected from Mt. Emei, Sichuan Province, China. They are Amynthas leshanensis sp. nov., Amynthas gilvus sp. nov., Amynthas retortus sp. nov. and Amynthas orbicularis sp. nov. The first three species could be assigned to the Amynthas sieboldi group and the last species could be assigned to the Amynthas aeruginosus group according to the definition of Sims and Easton. A. leshanensis sp. nov. has the male pore porophore surrounded by a large irregular-shaped pad which extends from 17/18–½ XIX, and the intestinal caeca are complex. A. gilvus sp. nov. has each male pore on a slightly raised elliptical glandular flat-top pad, with a pointed extension lateral to each porophore. Amynthas retortus sp. nov. has a pair of small, round post-setal genital papillae medial to male porophores on XVII, spermathecal seminal chambers are twisted into zigzags and accessory glands are present on spermathecae and prostate gland areas. A. orbicularis sp. nov. has the spermathecal pores near dorso-lateral, complex intestinal caeca complex, three accessory glands with long ducts near the male pores, and the spermathecal seminal chambers are twisted into zigzags. The barcode data (partial sequence of mitochondrial cytochrome c oxidase subunit I) of each species has been submitted to the National Center of Biotechnology Information GenBank.

http://zoobank.org/urn:lsid:zoobank.org:pub:5B82315E-5CF8-4048-87C4-B702021464B5     

Two new species of asterocherid (Copepoda: Siphonostomatoida) associated with a sponge from the Strait of Messina,Italy: taxonomic and ecological traits

Two new species of asterocherid associated with sponges are described from the Mediterranean Sea. They are Psilomyzon laetitiae sp. nov. and Psilomyzon sarcotragusicola sp. nov. The genus Psilomyzon consists of only one known species, P. pauciseta. The two new species can be easily distinguished from the cogener species by reduction of the endopod of leg 4. In P. pauciseta the leg 4 endopod is 3-segmented, with the third segment reduced; in both new species it is 2-segmented, with the second segment carrying an inner projection, possibly homologous to the third segment of the leg 4 endopod of P. pauciseta. In the two new species, the bifid outer process on male leg 4 second endopodal segment seems to be serially homologous to the similar processes on the same segment in legs 1–3, whereas the inner projection may represent a vestigial element of the third endopodal segment of leg 4.

http://zoobank.org/urn:lsid:zoobank.org:pub:33BF0653-BBA9-426B-B365-5D8C62DFD44A     

A new species of Kurixalus (Anura: Rhacophoridae) from northern Vietnam with comments on the biogeography of the genus

ABSTRACT

We describe a new species of rhacophorid frogs from Nghe An Province in northern Vietnam based on morphological and molecular evidences. Morphologically, Kurixalus gracilloides sp. nov. is distinguished from its congeners by a combination of the following diagnostic characters: body size small (snout–vent length 27.9–31.2 mm in males); head width subequal to head length; snout rounded with no dermal projection; canthus rostralis distinct, curved; vomerine teeth present; single internal vocal sac; iris golden-brown; small nuptial pad in finger I; dorsal surfaces golden-brown with a saddle-shaped dark marking; large dark spots on ventral surfaces absent; dermal fringes along outer edge of limbs; conical dermal appendage at the heel; skin on dorsum rough; skin on throat and chest granular; finger webbing rudimentary and toe webbing moderately developed, webbing formula I 2–2½ II 1½–3 III 1¾–3½ IV 3–1½ V. The new species is separated from all other congeners by uncorrected genetic distances ranging from 5.4% to 12.7% based on mitochondrial 16S rRNA gene. Phylogenetic analyses of mtDNA suggest that the new species is nested within a clade of Taiwanese and Yunnan Kurixalus with strong support values. The new species is currently known only from secondary bamboo forest in Pu Mat National Park, northern Vietnam, at elevations of 150 m asl. We suggest the new species should be considered as Near Threatened (NT) following the IUCN’s Red List categories.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:C1BF843F-2F31-4CED-B1F9-13A9035C77C9     

Indirect sperm transfer and sexual differences of Erythraeus phalangioides (De Geer), (Prostigmata,Erythraeidae)

The spermatophore and morphological differences in the sexual organs of Erythraeus phalangioides (De Geer) as well as the reproductive behaviour of males are described.     

Ultrastructure of spermatozoa and spermatogenesis in Octopus minor (Sasaki, 1920) (Cephalopoda: Octopoda)

Octopus minor is widely distributed along the coastal areas of the west Pacific Ocean. This paper investigates spermatozoa, spermiogenesis from the testes, and spermatophores using light and electron microscopy. Mature spermatozoa are about 650 µm long. The head includes mainly the acrosome and nucleus. The acrosome consists of a striated cone surrounded by a single helix. The nucleus is cylindrical, homogeneous and of high electron density. The neck is short and connected with the head through the internal nuclear fossa. The axoneme connects the head, neck and tail. The tail is divided into middle, principal and final pieces. The ‘9 + 9 + 2’ structure is surrounded by a mitochondrial sheath, which includes 9–11 mitochondria in transverse section. The sperm morphology is compared with the ultrastructure of other cephalopod spermatozoa, and taxonomic and phylogenetic implications are discussed.     

Environmental control versus phylogenic fingerprint in ontogeny: The example of the development of the stalk in the genus Guillecrinus (stalked crinoids,Echinodermata)

The stalk morphology of the deep‐sea stalked crinoid Guillecrinus changes a lot from juvenile to adult. As a result of its unusual morphology among the extant crinoids, its taxonomic and phylogenetic affinities remain unsettled. Distinctive morphological changes characterize the various growth stages in stalked crinoids. We conduct and discuss a detailed ontogenetic analysis of the stalk of the two species (Guillecrinus neocaledonicus and G. reunionensis) of this Indo‐Pacific genus, which was observed in its environment during submersible dives off New Caledonia. Analyses examined (1) morphological changes, (2) the degree of change in morphology, (3) architectural constraints, and (4) the functional constraints related to environmental factors. The relations between three levels of integration were examined: the ossicle (columnal), the stalk, and the complete individual. The changes in level of organization were estimated. The analysis reveals that the external stalk morphology of Guillecrinus goes from a pronounced xenomorphic type in juveniles, characterized by diversified columnal articulations, which provide the proximal and distal part of the stalk with a considerable degree of flexibility, to a dominant homeomorphic type in adults, characterized by columnal articulations which allow little or no movement. This ontogenetic change through a mosaic of heterochronic developments corresponds with a change in the hydrodynamic environment, from a turbulent to a laminar water flow, and from nutritional contraints. The extensive development of deep ligament fossae in adults and in the distal stalk of juveniles corresponds to a relatively low allocation of energy to the skeleton, rather than a functional necessity. Proximal columnals in juvenile Guillecrinus display characteristics of adult Hyocrinidae. Distal columnals exhibit the typical morphology observed in Bourgueticrinina. Juveniles stages of both proximal and distal columnals show a high degree of specialization (derived characters). Well‐supported classifications have typically placed the Bourgueticrinina and the Hyocrinidae in two very dissimilar groups. Specific characteristics from the three very different families Bathycrinidae, Guillecrinidae and Hyocrinidae appear to be expressed either separately (Hyocrinus or Bathycrinus) or together (Guillecrinus). Their expression appears to depend on functional and environmental constraints. The transformation of columnals from juvenile to adult shows the important role of hypermorphic processes. However, no evidence of phylogenetic recapitulation was observed. Does the evidence presented here support or disprove current taxonomic interrelationships? How does morphology relate to ontogeny? Is heterochrony involved?     

First record of the genus Koreanurina Najt and Weiner (Collembola: Neanuridae: Pseudachorutinae) from China,with description of two new species from Changbai mountain

The genus Koreanurina Najt and Weiner, 1992 is recorded for the first time from China. It is redefined and its similarity with the subfamily Caputanurininae is stressed. Two species are described from Changbai Mountain in North-East China: Koreanurina weinerae sp. nov. and K. alba sp. nov. The first species differs from the other species of the genus, mostly by its post-antennal organ located on the lateral edge of head (versus dorsolaterally), its central plate on head wider and the presence of only 1 + 1 chaetae on Th I (versus 2–3 + 2–3). K. alba sp. nov. differs from the other species of the genus mostly by the absence of body pigment, and the presence of only 1 + 1 chaetae posteriorly to the furcal rest (versus 2 + 2).

http://zoobank.org/urn:lsid:zoobank.org:pub:65366D33-890A-4E67-B581-5D32406C078F     

New findings of Hexalona-branch representatives in Brazil,with a description of Prenda gen. nov. (Crustacea: Anomopoda: Aloninae)

Altogether, Coronatella and Hexalona-branches are considered the main lineages of Aloninae – a subfamily of common bottom-dwelling microcrustaceans in freshwater environments. Although the taxonomic features of Brazilian members of the Hexalona-branch have been summarised for species from the costata-group and affinis-group, a revision of other widely distributed species in the world is still lacking in this country. The aim of this paper was to study the morphology of Brazilian populations from the guttata-group and intermedia-group, and to describe a new genus from the Hexalona-branch. The parthenogenetic females of Alona cf. guttata from Brazil have similar morphology when compared to data from the literature, but the armature of the terminal claw of its males seems to be different from those of Alona guttata sensu stricto, Alona barbulata and Alona werestschagini. The intermedia-group is formed by Alona elisae sp. nov., which seems to be endemic to the Cerrado of Brazil Central, and Alona isabellae sp. nov., which is widely distributed in Brazil; this species has a labral keel armed with 2–4 setulae, and postabdomen with setulae of lateral fascicles longer than the level of marginal denticles, morphological traits that differentiate it from Alona elisae sp. nov. Another endemic species from the Hexalona-branch is Prenda arvensis gen. nov. and sp. nov., which has two main head pores, a reduced seta on endite 1 of the first limb, sixth limb is a wide lobe. The potential of biodiversity from the Hexalona-branch from Brazil is still underestimated, and a global revision of the guttata-group and intermedia-group is very important for the progress of Aloninae taxonomy and systematics.

http://zoobank.org/urn:lsid:zoobank.org:pub:0A2E4A30-0C9C-43E8-8E72-1DEDA6AFF3C3     

A gynandromorph of Austrosimulium (Austrosimulium) australense (Schiner) from New Zealand (Diptera: Simuliidae)

Summary

A gynandromorph of Austrosimulium (Austrosimulium) australense (Schiner) is described. This individual had the head of a female, whereas the thorax and abdomen were a mosaic of male and female characters. The genitalia of both sexes were present, but only the female set was complete. Overall, the female characters of this specimen appeared to be more fully expressed than those of the male.     

Digging with ‘hands’: observations of food capture in the flying gurnard Dactylopterus volitans (Linnaeus, 1758)

ABSTRACT

Videofilms of a foraging flying gurnard (Dactylopterus volitans) were collected at Itaipu, Niterói, RJ, Brazil. Analysis revealed details of the use of anterior parts of the pectoral fins which act as digging ‘hands’ to access infaunal prey items that are subsequently captured by oral suction feeding. Each pectoral fin has two distinct sections articulated separately on the pectoral girdle. The digging ‘anterior pectoral fin’ mainly consists of segmented and flexible fin rays but has an anterior robust unsegmented ray that provides an edge to the ‘hand’, allowing penetration of the substratum. The huge ‘posterior pectoral fins’ are supported by unsegmented rays. Most digging episodes involved one ‘hand’ and consisted of 1–7 cycles of movement with frequencies 1.15–3.74 cycles s^?1. During a cycle, the ‘hand’ is moved forwards and medially above the substratum, then is twisted medially and simultaneously depressed so that the anterior unsegmented ray impacts and enters the substratum. The hand is then drawn backwards and laterally to disturb the substratum. To prevent upward pitching of the head during digging, the ‘posterior pectoral fins’ are both moved anteriorly and laterally to shift the centre of gravity forwards while the caudal and ?second dorsal fins continue to provide propulsive force.     

The status of Hemilecanium imbricans (Green) (Homoptera : Coccoidea) in Africa south of the Sahara

Summary

This paper describes the findings from two series of observations on variation in C. austropalpalis L. and R. In Series I the distribution of head capsule lengths of 174 larvae, collected from 11 breeding sites in S.E. Queensland, was polymodal. Polymodality was also shown by the wing lengths of 15♂, 27♀ reared from 7 of the sites. In Series II the head lengths of 302 larvae from 5 sites (one not in Series I) gave the same polymodality, interpreted as representing 3rd and 4th instars of two forms A (smaller) and B (larger). 276 of these larvae, grouped on head length, were reared on agar and small nematodes, producing 62♂, 70♀ C. austropalpalis and 13♂, 5♀ C. narrabeenensis. The latter was not the cause of the polymodality. Adult wing lengths were bimodal in each sex. Form B was longer winged than form A. Within each form there was no significant correlation between larval head length and adult wing length. Only one of the many additional characters (19 in ♀; 22 in ♂) examined, differed between the two forms. Form B had more distinctly patterned wings with the intercalary pale spot more obvious. The results are discussed.     

The mouthparts of two lophogastrids,Chalaraspidum alatum and Pseudochalaraspidum hanseni (Lophogastrida,Peracarida, Malacostraca), including some remarks on the monophyly of the Lophogastrida

Chalaraspidum alatum and Pseudochalaraspidum hanseni represent monotypic genera belonging to the Lophogastridae (Lophogastrida, Peracarida). Both species have previously been confused, although several characters permit their separation: e.g., C. alatum has only one small projection in the centre of the epimera of pleon segment 6 but P. hanseni has two distinct, pointed projections on the epimera of pleon segment 6. The palp of the maxilla is two-segmented in C. alatum and one-segmented in P. hanseni. The mouthparts, including labrum, mandibles, paragnaths, maxillula, maxilla and maxilliped are described in detail. Certain characters found in the two species, such as asymmetrical paragnaths, left mandible with semicircular incisor process, right mandible without lacinia mobilis, maxilliped with blade-shaped exopod are also found in the representatives of the remaining lophogastrid genera. These characters are interpreted as apomorphies supporting the monophyly of the Lophogastrida.     

Cercaria hastata sp. nov. (Digenea: Trematoda) in Bullia digitalis,a sandy beach surfing whelk from the Western Cape coast of South Africa: epidemiology and sex linked phenomena

Morphometric and sex linked phenomena in male Bullia digitalis, from the Western Cape coast of South Africa, are related to infection with a digenean microphallid larva described here for the first time and named Cercaria hastata. Penis shedding in Bullia is not uncommon. Most of the stumps are found on infected whelks, and this is probably due to parasitic inhibition of an otherwise rapid regeneration. The infection also abolishes sperm production. Stumps were never seen on sperm producing males, all of which have large penes, and in non-infected males, shedding occurs only in non-producers. In large non-infected Bullia, those which have underdeveloped penes and are non-producers of sperm may be transient intersexes. This is supported by the exhibition of protandry indicators such as brooding, nonsize preferential mate selection and gregariousness. Infection prevalence is size dependent, large whelks being more commonly infected; but parasitic gigantism is thought unlikely as Bullia is iteroparous.