Barrie G. M. Jamieson

ON THE PHYLOGENY AND HIGHER CLASSIFICATION OF THE OLIGOCHAETA

Abstract— The 50 oligochaete taxa representing all families of “opisthoporous” oligochaetes (Aliuroididae, earthworms and aquatic “megadriles”) together with two representatives of the Haplotaxidac and three examples of “microdiles” were subjected to cladistic analysis using the PAUP program. Sixty‐eight characters used in the analyses were derived from a comprehensive range of somatic and genital systems. The optimal result, in terms of maximal number of characters and taxa and of parsimony, produced two trees (consistency index 0.362) differing only in the placement of the monotypic clade for the family Lumbriculidae. From a line originating from the presumed octogonadial ancestor, the following branches were derived, in sequence from the basal to most derived (new taxa asterisked): subclass Randiellata* (order Randiellida*, Randiellidae); subclass Tubificata* (order Tubificida, Tubincidae, Naididae computed and others not computed); subclass Lumbriculata* (order Lumbriculida, Lumbriculidae); superorder Haplotaxidea* (order Haplotaxida, Haplotaxidae); order Moniligastrida (Moniligastridae); suborder Alluroidina (Aliuroididae and Syngenodrilidae); cohort Aquamegadrili* (with, in succession, superfamilice Sparganophiloidea, Sparganophilidae; Biwadriloidea, Biwadrilidac, and Almoidca—Lutodrilidac and Almidae, including Criodrilus); superfamily Eudriloidea*, superfamily Lumbricoidea and, as the adelphotaxon of the latter, the superfamily Megascolecoidea. Intermediate nodes were given the following names, with the adelpholaxon through to the Megascolecoidea, M, in parentheses: subclass Diplotesticulata (Haplotaxidea—M); superorder Metagynopohora* (Moniligastrida—M); order Opisthopora (Alluroidina M); suborder Crassiclitellata* (Aquamegadrili — M); cohort Terrimegadrili* (Ocnerodriloidea M); unnamed (Eudriloidea M); unnamed (Lumbricoidea and Megascolecoidea). Recognition of the Randiellata, which alone were added intuitively and not computed, and the position of the Lumbriculata, are tentative. Location of the Lumbricoidea as the adelphotaxon of a restricted Megascoecloidea is heuristic, but the alternative depiction of lumbricoids in some analyses, as the adelphotaxon of an ocnerodrilid‐eudrilid‐megascolecoid clade (the conventional Megascolecoidea s. lat.), is not conclusively dismissed.

PHYLOGENETIC ANALYSIS OF THE MONOGENEA AND THEIR RELATIONSHIPS WITH DIGENEA AND EUCESTODA INFERRED FROM 28S RDNA SEQUENCES

Platyhelminth phylogeny is controversial. Phylogenetic analyses of the partial domain C1 and the full domains D1 and C2 (358 nucleotides) from the 28S ribosomal RNA gene for 21 species from the Monogenea, Digenea, Cestoda, and, as the outgroup, Tricladida reveal major departures from prevailing theory. The Digenea and not the Monogenea (Monopisthocotylea and Polyopisthocotylea) form the sister group of the cestodes; the Monopisthocotylea and Polyopisthocotylea are each monophyletic, but the Monogenea do not form a monophylum; the sister group of the Digenea + Cestoda is the Polyopisthocotylea; and Monopisthocotylea are the sister group of all other parasitic flatworms.

The ultrastructure of the spermatozoon of Neochasmus sp. (Cryptogonimidae, Digenea, Trematoda) and its phylogenetic significance

Abstract Jamieson B. G. M. and Daddow L. M. 1979. The ultrastructure of the spermatozoon of Neochasmus sp. (Cryptogonimidae, Digenea, Trematoda) and its phylogenetic significance. International Journal for Parasitology 12 : 547–559. The typical spermatozoon is filiform, monopartite and internally strongly asymmetrical, with a mean length of 254 μm. Its two axonemes are wholly incorporated though not deeply. The six major regions, in anteroposterior (proximal-distal) sequence, are: acrosomoid, prenuclear, uniaxonemal, nuclear, intermediate (amitochondrial), posterior mitochondrial and posterior amitochondrial regions. Centrioles and flagellar rootlets, present in the spermatid, are absent from the spermatozoon. The right axoneme (axial unit) originates more anteriorly than the left and anteriorly bears an acrosome-like projection (acrosomoid). Spinose regions carrying epiplasmalemmal projections are reported for the first time in the Digenea. Dimorphism exists as replacement of the typical posterior mitochondrial and amitochondrial regions by an amitochondrial region characterized by asymmetrical distribution of spines around one axoneme. Excepting known schistosomatid sperm, the digenean sperm is diagnosed by the combination of three characters: cortical microtubules, two fully incorporated 9 + 1 axonemes and presence of mitochondria although no one of these characters is limited to the group. Subtle intertaxon variations occur.

Phylogeny of the monopisthocotylea and Polyopisthocotylea (Platyhelminthes) inferred from 28S rDNA sequences.

This study focuses on the phylogenetic relationships within the Polyopisthocotylea and Monopisthocotylea, two groups that are often grouped within the monogeneans, a group of disputed paraphyly. Phylogenetic analyses were conducted with multiple outgroups chosen according to two hypotheses, a paraphyletic Monogenea or a monophyletic Monogenea, and with three methods, namely maximum parsimony, neighbour joining and maximum likelihood. Sequences used were from the partial domain C1, full domain D1, and partial domain C2 (550 nucleotides, 209 unambiguously aligned sites) from the 28S ribosomal RNA gene for 16 species of monopisthocotyleans, 26 polyopisthocotyleans including six polystomatids, and other Platyhelminthes (61 species in total, 27 new sequences). Results were similar with outgroups corresponding to the two hypotheses. Within the Monopisthocotylea, relationships were: ¿[(Udonella, capsalids), monocotylids], (diplectanids, ancyrocephalids)¿; each of these families was found to be monophyletic and their monophyly was supported by high bootstrap values in neighbour joining and maximum parsimony. Within the Polyopisthocotylea, the polystomatids were the sister-group of all others. Among the latter, Hexabothrium, parasite of chondrichthyans, was the most basal, and the mazocraeids, mainly parasites of clupeomorph teleosts, were the sister-groups of all other studied polyopisthocotyleans, these, mainly parasites of euteleosts, being polytomous.

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.

Reproductive biology and phylogeny of Anura

An Overview of Anuran Phylogeny, Classification and Reproductive Modes: William E. Duellman The Gross Anatomy of the Reproductive System: Michael J. Tyler Oogenesis: Sara S. S nchez and Evelina I. Villecco Endocrinology of Reproduction: Silvia N. Fern ndez and In s Ramos Spermatogenesis and the Mature Spermatozoon: Form, Function and Phylogenetic Implications: David M. Scheltinga and Barrie G.M. Jamieson An Overview of Breeding Glands: Rossana Brizzi, Giovanni Delfino and Silke Jantra Internal Fertilization in the Anura with Special Reference to Mating and Female Sperm Storage in Ascaphus: David M. Sever, William C. Hamlett, Rachel Slabach, Barry Stephenson, and Paul A. Verrell Parental Care: A Phylogenetic Perspective: Richard M. Lehtinen and Ronald A. Nussbaum Development: Ronald Altig Molecular Development: Brian Keyv

The ultrastructure of the spermatozoa of bufonid and hylid frogs (Anura, Amphibia): implications for phylogeny and fertilization biology

Comparison of the spermatozoa of Bufo marinus, six Australian species of the family Hylidae, and the myobatrachine Adelotus brevis, with those of 41 other species of frogs, in a total of 12 investigated families allows the following phylogenetic inferences: the bufonoids (myobatrachids, leptodactylids, hylids, and bufonids) form a monophyletic assemblage with a single synapomorphy: the presence of a conical subacrosomal perforatorium. This structure is analogous to, rather than homologous with, the perforatorium in archaeobatrachians, which differs notably in being an endonuclear structure. The hylid‐leptodactylid‐bufonid assemblage is the sister‐group of the Myobatrachidae (Australian ‘leptodactylids’). Myobatrachids are distinguished by two. albeit weak, synapomorphies, the presence of well‐defined pericentriolar material, and the extension of the axial rod up the centriolar fossa, the latter condition approached in the bufonid Nectophrynoides. The bufonid, leptodactylid (sensu strictu), and hylid families are united, and separated from myobatrachids, by a single synapomorphy: a thick collar‐like cytoplasmic sheath that emanates from the centriolar region, is separated from the flagellum by a cytoplasmic canal, and contains the mitochondria. Litoria fallax, L. gracilenta, and L. lesueuri are associated by a unique synapomorphy, hypermorphosis of the minor fibre (juxta‐axonemal fibre), though this is approached in Bufo bufo. However, there is no spermatological evidence supporting the recognition of Australian hylids (pelodryadids) as a group distinct from the remaining eubufonoids and, specifically, from the Hylidae. Evidence is presented in support of the tentative proposal that the Lissamphibia were primitively internally fertilizing.

Further spermatological evidence for including the pentastomida (tongue worms) in the Crustacea

Abstract The ultrastructure of the spermatozoa of three species of the Pentastomida is investigated: the cephalobaenids Raillietiella sp. and Cephalobaena tetrapoda, and the porocephalid Porocephalus crotali. Phylogenetic relationships of pentastomids with their putative maxillopodan and remipedian relatives have been deduced from sperm ultrastructure intuitively and by parsimony analysis using the PAUP program of Swofford (1990, Version 3.01, Illinois Natural History Survey, Champaign, IL). A remarkable degree of homogeneity in the ultrastructure of the spermatozoa of cephalobaenids and porocephalids is demonstrated and a sister-group relationship of pentastomids and Branchiura, first proposed by Wingstrand (1972, Kongelige Danske Videnskab Selskab Biologiske Skrifter19: 1–72), is confirmed. Spermatozoal synapomorphies of the Pentastomida and the branchiuran Argulus include: absence of an acrosome vesicle and filament in the mature spermatozoon; presence of a pseudoacrosome, about 30 μm long, divisible into a dorsal and a ventral component (the dorsal and ventral rod), and derived from pericentriolar structures; continuation of the dorsal rod with the dorsal ribbon of an axonemal sheath and with material embedding the centriolar doublets 1, 2 and 9; continuation of the ventral rod with material embedding the more ventrally situated doublets; presence of the axonemal sheath; presence of a connective from the dorsal ribbon to axonemal doublet 1; presence in the spermatid of nine dense fibres peripheral to the doublets; great elongation of the three mitochondria parallel to the nucleus; and total incorporation of the axoneme in the spermatozoon so that a free flagellum is absent. The sperm of the pentastome-branchiuran assemblage appear to be the most highly evolved of the flagellate crustacean sperm.

Ultrastructural comparison of the spermatozoa of Ranina ranina (Oxystomata) and of other crabs exemplified by Portunus pelagicus (Brachygnatha) (Crustacea, Brachyura)

SummaryFeatures shared between the sperm of Ranina ranina and of the so-called “higher Brachyura” (the Oxyrhyncha — Cancridea — Brachygnatha assemblage, OCB) include: (1) the large subspheroidal acrosome (a synapomorphy of the Raninoidea + the OCB contrasting with the disc-shaped Dromioidea acrosome); (2) enclosure of the acrosome by a thin layer of cytoplasm which is in turn cupped by the nucleus; (3) extension of the nucleus as lateral arms and as a posterior median process (this process is absent in the more advanced families, including portunids); (4) extension of the cytoplasm into the basal region of each nuclear arm; and (5) topographical equivalence and presumed homology of components of the acrosome, viz. the electron dense capsule; inner and outer dense zones surrounding the longitudinal axis; peripheral vesicular contents; a perforate or, in Portunus, an imperforate, apical operculum; subopercular- or subcap-zone; and a basally open subacrosomal chamber enclosing perforatorial material. Significant differences of the Ranina sperm from those of the OCB, including Portunus, are: (1) anterior termination of the subacrosomal space at the equator of the acrosome and its conical form (plesiomorphy?), in the latter assemblage reaching the operculum; (2) differentiation within the subacrosomal material of a coiled, filiform putative perforatorium (plesiomorphy or apomorphic homoplasy with Anaspidacea?) whereas the entire subacrosomal contents in the OCB form a stout perforatorial rod; (3) subdivision from the acrosome vesicle in Ranina of a posterior acrosomal chamber with differentiation of the walls of this, lining the subacrosomal chamber, as longitudinal corrugations (Raninoidea autapomorphies); and (4) plesiomorphic persistence of numerous well developed, simple mitochondria in contrast to their degeneration, with greater development of a myelin-like lamellar complex, in the OCB. Spermatologically, the Raninoidea thus appear to be the plesiomorphic adelphotaxon of the Oxyrhyncha — Cancridea — Brachygnatha assemblage.

The ultrastructure of the spermatozoa of Petalomera lateralis (Gray) (Crustacea, Brachyura, Dromiacea) and its phylogenetic significance

Summary The dromiid sperm, as exemplified by Petalomera lateralis and Dromidia antillensis, differs markedly from spermatozoa of other crabs (the Oxystomata-Oxyrhyncha-Cancridea-Brachygnatha assemblage) in the discoid, relatively undifferentiated acrosome capping and not embedded in the nucleus (plesiomorphies); the capitate form of the perforatorium and the composition of this (autapomorphies); the greater, apomorphic, reduction of cytoplasm and organelles, including mitochondria and centrioles; and the absence (Petalomera) or brevity (Dromidia) of nuclear arms. In view of some similarities of the acrosome to those of Eubrachyura suggestive of relationship, brevity of arms may be secondary by reduction. Presence of well developed nuclear arms is a synapomorphy of all investigated non-dromiid brachyurans and of the Palinura, Astacidea and Anomura while absence is a symplesiomorphy of other Malacostraca. If brevity of arms in dromiids were plesiomorphic, the Dromiacea might be derived from early decapods b...