Description of a new Central African earthworm, Petroscolex centenarius gen. et sp. nov. (Crassiclitellata, Eudrilidae), celebrating the 100th birthday of Pietro Omodeo.

Prof. Pietro Omodeo (University of Siena, Italy), the world-renowned earthworm taxonomist and evolutionary biologist, was born in Cefalù, Sicily, Italy on the 27th September, 1919. He celebrates his 100th birthday in 2019 and members of the international community of earthworm taxonomists salute him with Petroscolex centenarius gen. et sp. nov., a new megadrile taxon discovered in 1991 by him but which has not been formally described until now. The many important contributions of Omodeo to oligochaetological research are briefly mentioned.

An Ancient Divide in a Contiguous Rainforest: Endemic Earthworms in the Australian Wet Tropics.

Understanding the factors that shape current species diversity is a fundamental aim of ecology and evolutionary biology. The Australian Wet Tropics (AWT) are a system in which much is known about how the rainforests and the rainforest-dependent organisms reacted to late Pleistocene climate changes, but less is known about how events deeper in time shaped speciation and extinction in this highly endemic biota. We estimate the phylogeny of a species-rich endemic genus of earthworms (Terrisswalkerius) from the region. Using DEC and DIVA historical biogeography methods we find a strong signal of vicariance among known biogeographical sub-regions across the whole phylogeny, congruent with the phylogeography of less diverse vertebrate groups. Absolute dating estimates, in conjunction with relative ages of major biogeographic disjunctions across Australia, indicate that diversification in Terrisswalkerius dates back before the mid-Miocene shift towards aridification, into the Paleogene era of isolation of mesothermal Gondwanan Australia. For the Queensland endemic Terrisswalkerius earthworms, the AWT have acted as both a museum of biological diversity and as the setting for continuing geographically structured diversification. These results suggest that past events affecting organismal diversification can be concordant across phylogeographic to phylogenetic levels and emphasize the value of multi-scale analysis, from intra- to interspecies, for understanding the broad-scale processes that have shaped geographic diversity.

Ultrastructure of the spermatid of Caprimulgus europaeus Linnaeus 1758, the European nightjar (Aves; Caprimulgidae), with phylogenetic implications.

The sperm of Caprimulgus europaeus is typical of other nonpasserines in many respects. Features shared with Paleognathae and Galloanserae are the conical acrosome, shorter than the nucleus; the presence of a perforatorium and endonuclear canal; the presence of a proximal as well as distal centriole; the elongate midpiece with mitochondria grouped around a central axis (here maximally six mitochondria in approximately 10 tiers); and the presence of a fibrous or amorphous sheath around the principal piece of the axoneme. A major (apomorphic) difference from paleognaths and galloanserans is the short distal centriole, the midpiece being penetrated for most of its length by the axoneme and for only a very short proximal portion by the centriole. Nonpasserines differ from paleognaths in that the latter have a transversely ribbed fibrous sheath, whereas in nonpasserines it is amorphous, as in Caprimulgus, or absent. The absence of an annulus is an apomorphic feature of Caprimulgus, apodiform, psittaciform, gruiform, and passerine sperm, homoplastic in at least some of these. In contrast to passerines, in Caprimulgus the cytoplasmic microtubules in the spermatid are restricted to a transient longitudinal manchette. The structure of the spermatid and spermatozoon is consistent with placement of the Caprimulgidae near the Psittacidae, but is less supportive of close proximity to the Apodidae, from DNA-DNA hybridization and some other analyses.

Ultrastructure of the mature spermatozoa of caecilians (Amphibia: Gymnophiona).

The spermatozoa of Gymnophiona show the following autapomorphies: 1) penetration of the distal centriole by the axial fiber; 2) presence of an acrosomal baseplate; 3) presence of an acrosome seat (flattened apical end of nucleus); and 4) absence of juxta-axonemal fibers. The wide separation of the plasma membrane bounding the undulating membrane is here also considered to be apomorphic. Three plesiomorphic spermatozoal characters are recognized that are not seen in other Amphibia but occur in basal amniotes: 1) presence of mitochondria with a delicate array of concentric cristae (concentric cristae of salamander spermatozoa differ in lacking the delicate array); 2) presence of peripheral dense fibers associated with the triplets of the distal centriole; and 3) presence of a simple annulus (a highly modified, elongate annulus is present in salamander sperm). The presence of an endonuclear canal containing a perforatorium is a plesiomorphic feature of caecilian spermatozoa that is shared with urodeles, some basal anurans, sarcopterygian fish, and some amniotes. Spermatozoal synapomorphies are identified for 1) the Uraeotyphlidae and Ichthyophiidae, and 2) the Caeciliidae and Typhlonectidae, suggesting that the members of each pair of families are more closely related to each other than to other caecilians. Although caecilian spermatozoa exhibit the clear amphibian synapomorphy of the unilateral location of the undulating membrane and its axial fiber, they have no apomorphic characters that suggest a closer relationship to either the Urodela or Anura.

Spermatozoal ultrastructure in the spiny lobster Jasus novaehollandiae Holthuis, 1963 (Palinuridae, Palinura, Decapoda).

The spermatozoal ultrastructure of the spiny lobster Jasus novaehollandiae is most similar to that in other investigated palinurans and, in particular, to the spermatozoa of Panulirus species. Shared characters include the globular nucleus penetrated by the bases of three or more microtubular arms; an anteriorly situated cytoplasmic zone with mitochondria and conspicuous lamellar bodies; a complex, four-zoned acrosomal vesicle (however, lacking the crystalline region present in Panulirus) with a homogeneous region; a scroll region; a flocculent region; and a region of periacrosomal material that forms finger-like involutions into the flocculent region. The related scyllarid slipper lobsters (Scyllarus and Thenus) possess spermatozoa with acrosome morphology similar to that of Jasus, but the sperm is generally more flattened, numerous radiating acrosome fins are present, and the microtubular arms (in Scyllarus) are cytoplasmic in origin and not nuclear. Sperm morphology provides preliminary evidence in support of the hypothesis of two independent lines of evolution in the Palinuridae but investigation into additional taxa within this group is required. J. Morphol. 236:117-126, 1998. © 1998 Wiley-Liss, Inc.

PARSIMONY ANALYSIS OF THE PHYLOGENY OF SOME OLIGOCHAETA (ANNELIDA) USING SPERMATOZOAL ULTRASTRUCTURE.

Abstract- Quantitative and qualitative ultrastructural data from the spermatozoa of 11 oligochaete species, representing all orders (Tubificida, Lumbriculida, and Haplotaxida, yielded a single most parsimonious tree, using the Wagner-tree (PAUP) method of Swofford (1984). The Haplotaxida (Haplotaxis through Megascolecidae) form a discrete monophyletic group, with inclusion, however, of the reproductively exceptional tubificidan Phreodrilus. Bythonomus, representing the Lumbriculidae, the phylogenetic position of which has been so controversial, forms the plesiomorphic sister group of the Haplotaxida, a position which is supported from other evidence. The Tubificida, represented by two tubificids (Rhizodrilus and Limnodriloides) and by the enchytraeid Lumbricillus, are plesiomorphic relative to the lumbriculid+haplotaxid assemblage and lie at the base of the tree, but all three appear mutually paraphyletic. Monophyly of the Tubificida cannot, however, be considered conclusively refuted from the small sample used. Lumbricillus appears to have the most plesiomorphic sperm in the investigated oligochaetes. The Megascolecidae (Amynthas and Fletcherodrilus) form the highest affinity and most apomor-phic group. The implications of relative apomorphy of the Lumbriculida (Bythonomus) are profound. Branchiobdellids and leeches are generally regarded as sharing a common ancestry with lumbriculids and would, because of the revised position of the latter, cladistically constitute part of the Oligochaeta sensu lato.