A revision of the Australian earthworm genus Woodwardiella with descriptions of two new genera (Megascolecidae: Oligochaeta)

The genus Woodwardiella Stephenson, 1925, from which oriental species were excluded by Gates (1938, 1939, 1960), is further restricted to include only five south-western Australian species, a Tasmanian species and provisionally, as species inquirenda , the Victorian W. healesi (Michaelsen, 1923) and a further Tasmanian species, W. mortoni Spencer, 1895.
Twelve species originally assignable to Woodwardiella , of which one is reduced to a junior synonym, constitute a new genus, Heteroporodrilus , known only from the southeastern portion of the Australian mainland.
Woodwardiella punctatus (Spencer, 1900) is shown to be a junior synonym of the sympatric Victorian W. smithi (Fletcher, 1889a) which is placed in the new monotypic genus Pseudoperichaeta.
Plutellus manifestus (Fletcher, 1889), which has tubular prostates and belongs to the family Acanthodrilidae s. Gates, shows close affinities with Heteroporodrilus which is referable to the family Megascolecidae s. Gates, characterized by racemose prostates. Variation in the form of the prostates can no longer be accorded even subfamilial significance and Plutellus is transferred to the subfamily Megascolecinae. Close morphological similarity demonstrated between P. manifestus and P. heteroporus Perrier, 1873, the type species of the genus, suggests a basis for restriction of the heterogeneous assemblage known as Plutellus.
Diporochaeta davallia Spencer, 1900, has close affinities with Pseudoperichaeta and, like this genus, has tufted meronephridia anteriorly.     

New earthworm species of the genus Amynthas Kinberg, 1867 from Thailand (Clitellata, Oligochaeta, Megascolecidae)

Four new species of terrestrial earthworms from the zebrus-group in the genus Amynthas Kinberg, 1867, are described from Nan province, north Thailand: Amynthas phatubensissp. n., from Tham Pha Tub Arboretum, Amynthas tontongsp. n., from Tontong Waterfall, Amynthas borealissp. n., from Chaloemprakiat district, and Amynthas srinansp. n., from Srinan National Park.After comparing with the two closely related Laos species Amynthas chandyi Hong, 2008 and Amynthas namphouinensis Hong, 2008, the four new species show clear morphological differences, and also it is confirmed that there are no previous records of the species described here. Amynthas phatubensissp. n. is the largest (longest) sized of these earthworms and is the only species that lives in limestone habitats. The genital characters are different among them and also from the two Laotian species. Molecular systematics would be a good method for further analysis of the diversity and species boundaries in SE Asian Amynthas.     

A new earthworm species of the genus Drawida Michaelsen(Oligochaeta: Moniligastridae) from China

A new species of terrestrial earthworms is described as Drawida dandongensis sp. nov. from Dandong, Liaoning, China. It is distinguished from others by a pair of spermathecal pores lie in the ventral of 7/8 intersegmental furrow, and a pair of male pores lie in 10/11 intersegmental furrow, between setae b and c.     

Two new Korean earthworms (Annelida,Oligochaeta, Megadrilacea,Megascolecidae)

Two Korean endemic pheretimoid Amynthas Kinberg, 1867 species belonging in family Megascolecidae s. stricto are sketched, dissected and described. Amynthas daeari Blakemore sp. n. has spermathecae in 6/7/8 complying with an Amynthas tokioensis spp-group, whilst Amynthas jinburi Blakemore sp. n. has spermathecal pores in 5 & 6 strictly complying with Sims and Easton’s (1972) Amynthas canaliculatus-group. A definitive COI gene barcode is provided for the holotype of Amynthas daeari but the age since collection or preservation of the Amynthas jinburi type in 2000 precluded its mtDNA extraction at this time.     

The earthworm genus Pleionogaster (Clitellata: Megascolecidae) in southern Luzon, Philippines

An earthworm biodiversity survey of the Philippines has yielded 14 new species of the perichaetine megascolecid genus Pleionogaster, previously known from only a few species from scattered Philippine locations. Bicol, the southern peninsula of Luzon, has intact forests on several isolated volcanic peaks and other remote areas. Collections made in these forests yielded the following new species, here presented by type location: Mt. Malinao, Pleionogaster albayensis, P. bicolensis, P. castilloi, P. malinaoensis, P. tiwiensis; Mt. Isarog, P. ffitchae, P. isarogensis; Mt. Bulusan, P. bulusanensis, P. hongi, P. sorsogonensis; Catanduanes Island, P. nautsae, P. viracensis; Caramoan Peninsula, P. caramoanensis, P. nillosae. Most of the species were found only in the neighborhood of the type locality, but P. bicolensis occurs in two locations in northern Bicol. Intraspecific variation in P. castilloi was observed between northern and southern flanks of Mt. Malinao. The importance of several previously overlooked Pleionogaster traits is demonstrated by their homogeneity within species reported here.Full article published online at http://www.senckenberg.de/odes/06-08.htm.     

Variability of sexual organ possession rates and phylogenetic analyses of a parthenogenetic Japanese earthworm, Amynthas vittatus (Oligochaeta: Megascolecidae)

Although earthworms are hermaphroditic animals with biparental sexual reproduction, some parthenogenetic species have been found. Evolutionary trends in parthenogenetic earthworms revealed a reduction in the reproductive organs. To clarify the phylogenetic relationships of parthenogenetic earthworms with different degree of degraded reproductive organs, we conducted a morphological analysis of the reproductive organs and molecular phylogenetic analyses of Amynthas vittatus which usually degraded a part of reproductive organs. Morphological analysis revealed that almost all individuals collected around Mt. Aobayama, Sendai city of northeastern Japan, possessed male pores, while individuals collected from areas located across Hirose River did not. Phylogenetic analysis using mitochondrial DNA sequences of 48 individuals representing 20 populations indicated that almost all individuals collected around Mt. Aobayama belonged to a different lineage from the other populations collected around Sendai, and that almost all individuals collected from across Japan belonged to the latter lineage. We suggest that the difference in the male pore possession rate was caused by histories of each population, but the A. vittatus population found on Mt. Aobayama belongs to a different lineage as compared to the other Japanese populations and not the primitive population. Thus, the parthenogenetic earthworm A. vittatus has undergone at least two morphological evolutionary processes.     

Growth,reproductive biology and life cycle of the vermicomposting earthworm, Perionyx ceylanensis Mich. (Oligochaeta: Megascolecidae)

In the present study, an attempt has been made to study the growth, reproduction and life cycle of the earthworm, Perionyx ceylanensis Mich. in cowdung for the period of 340 days. Results showed that the overall mean growth rate was 1.79, 1.57 and 1.34 mg/worm/day respectively for the worms cultured singly, in batches of four and eight. Cocoon production rate was found between 0.85 and 0.94 cocoons/worm/day and the hatching success between 74.67% and 82.67%. The majority of the cocoons (95.16–96.77%) hatched only one hatchling. Worms raised singly also produced viable cocoons indicating that P. ceylanensis reproduce parthenogenetically. The life cycle of the worms cultured singly was ±57 days and it was ±50 days for the worms cultured in batches of four and eight. There is a vast scope to utilize P. ceylanensis for vermiculture practices due to short period of life cycle.     

Life-cycle and karyology of Branchiura sowerbyi Beddard (Oligochaeta,Tubificidae)

Data on the life-cycle of a population of Branchiura sowerbyi Beddard in a water-lily tank at the Botanical Garden in Padua are reported. The breeding period is from April to July, after which the reproductive system is partially resorbed (August–September) and reformed later in the autumn. The karyology of the species was also studied, and revealed 38 mitotic chromosomes in the gonia, and 19 bivalents in the primary spermatocytes and in the primary oocytes.     

The fine structure of blood follicles in the earthworm genera Amynthas and Lumbricus (Annelida: Oligochaeta)

Blood follicles of the earthworm Amynthas are hemoglobin-containing, sac-like dilatations of blood vessels which connect to the general circulation. Grape-like clusters of follicles are found posterior to the pharynx, among tufts of micronephridia, and single follicles are located among cells of the pharyngeal gland. In Lumbricus, follicles take the form of simple swellings and irregular-shaped diverticula of nephridial capillaries. The fundamental structure of the wall of follicles and of vessels in both genera is the same and consists of two layers: an extracellular vascular lamina and an outer (coelomic) covering of smooth muscle-like myoperithelial cells. Hemocytes may be free and circulating or they may facultatively attach to the vascular lamina as littoral cells, constituting an incomplete endothelium-like surface. Hemocytes that appear to be in the process of attaching or detaching are rounded, while adherent cells are flattened and elongate. Free and littoral hemocytes actively endocytose packets of circulating extracellular hemoglobin. Hemocytes within follicles possess radiating cell processes which also endocytose hemoglobin. Although these cells were presumed to secrete hemoglobin, staining with 3,3′-diaminobenzidine confirms the presence of hemoglobin only within pinosomes and not within protein-synthesizing or packaging organelles. The presence of hemosiderin-like bodies suggests that follicular hemocytes catabolize hemoglobin. Blood follicles apparently provide a means of significantly increasing cell-surface area for hemoglobin processing, without substantially increasing the volume and pumping load of the circulatory system.     

A new Australian genus of Stenosmylinae (Neuroptera: Osmylidae)

ABSTRACT. A new genus of Stenosmylinae, Carinosmylus gen.n ., is described from south-eastern Australia. The single included species, C.durus sp.n ., is an apparently advanced form allied to Stenosmylus Kriiger and Stenolysmus Kimmins, but shows more extensive fusion and elaboration of the posterior abdominal segments. A key to stenosmyline genera is provided.     

The earthworm fauna of the Carpathian Basin with new records and description of three new species (Oligochaeta: Lumbricidae)

A review of the earthworm fauna of the Carpathian Basin recorded a total of 97 earthworm species of which three: Dendrobaena vladeasa, Octodriloides izanus and Octodrilus parvivesiculatus spp. nov. are new to science. A biogeographic analysis of the earthworm fauna revealed an extraordinarily high rate of endemism (40.21%) which is explained by the special Quaternary and tectonic history of the region.     

Life cycle of the earthworm Octodrilus complanatus (Oligochaeta, Lumbricidae)

The earthworm Octodrilus complanatus (Dugès, 1828) is a large-sized species often found in grasslands and pastures, with a wide distribution area in Europe and North Africa. In order to determine the characteristics of its life cycle, earthworms of this species were cultured from hatching until they reached maturity. Development rates, cocoon production, and incubation period were recorded under controlled conditions. On average, individuals of O. complanatus reared in isolation from hatching reached maturity at day 150 and body weight at maturity ranged between 6 and 8 g. The cocoon incubation period was 66 days, and only one individual hatched from each cocoon, with a mean hatchability of 55%. Reproductive rate showed by O. complanatus after mating was of 52 cocoons per earthworm per year. The results showed that the life cycle of O. complanatus was characterized by both low growth rates and low fecundity. Specific features in life history traits of O. complanatus were compared with those of species of the genus Octodrilus and other related earthworms.     

Size-assortative mating in the earthworm Eisenia fetida (Oligochaeta, Lumbricidae)

In many species of simultaneous hermaphrodites, body size correlates with fecundity, and larger partners are preferred to small ones. Since sperm exchange is usually reciprocal, small individuals may be rejected by larger partners resulting in size-assortative mating. We studied the mating patterns in a natural population of the simultaneous hermaphroditic earthworm Eisenia fetida (Oligochaeta, Lumbricidae). We found that size-assortative mating processes existed, with variance in body weight within pairs lower than between pairs in mating earthworms. This non-random mating pattern probably reveals the existence of mate selection in this species, which lives at elevated densities with high availability of potential mates.