The Griffithsieae group of the Ceramiaceae (Rhodophyta) and its southern Australian representatives

1976 ◽  
Vol 24 (4) ◽  
pp. 509 ◽  
Author(s):  
RN Baldock

The genus Griffithsia C. Agardh, with its type species G. corallinoides (L.) Batters, is characterized by subdichotomous filaments of large multinucleate cells; by a fertile axis of three small discoid cells of which the subapical cell produces 1(-2) procarp(s), whilst the lowermost cell (termed the hypogenous) produces abaxially an involucre of 2-celled branches; by a large fusion cell; and by the production of tetrasporangia and spermatangia on whorls of fascicles which often bear involucral cells, or are surrounded by an involucre from the vegetative cell beneath the fascicles, or are naked. Some southern Australian species previously placed in Monosporus Solier or Neomonospora Setchell & Gardner, but which produce tetrasporangia and reproduce sexually, are related to G. tenuis C. Agardh and G. barbata C. Agardh. They are characterized by subdichotomous filaments of multinucleate elongate cells; by a 3-celled fertile axis of which the subapical cell produces a procarp, and the hypogenous cell enlarges during procarp development and produces a whorl of 1-celled involucral branches; by a large fusion cell; and by tetrasporangia and spermatangial heads produced singly either from the basal cell of a trichoblast, or on a separate clavate pedicel. These species are referred to the genus Anotrichium Naegeli, differing from Griffithsia mainly in the spermatangial heads and tetrasporangia. The genus Monosporus Solier, represented with certainty in southern Australia only by M. australis (Harvey) J . Agardh, is retained as a form genus for those species which produce monosporangia but for which sexual reproduction is unknown. Study of Halurus equisetifolius (Lightfoot) Kuetzing, the type species of Halurus Kuetzing, from England, shows that this genus is characterized by irregularly branched axes with dichotomous whorl-branchlets; by the successive production of several fertile axes each of 3 small cells and equivalent to a condensed, dichotomous, branch system; and by a subapical procarp and large fusion cell. The involucre consists of vegetative whorl-branchlets and also a whorl of 1-celled branches from the enlarged hypogenous cell of the fertile axis. Halurus thus differs from Griffithsia mainly in cystocarpic features and the presence of whorl-branchlets. Griffithsia setacea (Ellis) C. Agardh should probably be referred to Halurus. An evolutionary trend towards reduction in the Griffithsieae is suggested: whorl-branchlets have been reduced to trichoblasts and fertile whorl-branchlets to whorls of fascicles. The number of procarps in a branch system and the female, spermatangial and tetrasporangial involucres show a reduction sequence.

1998 ◽  
Vol 76 (8) ◽  
pp. 1433-1445 ◽  
Author(s):  
M L Mendoza ◽  
J Cabioch

The two CorallinalesPhymatolithon calcareum and Lithothamnion corallioides are the main components of European maerl communities. A large majority of the thalli are free-living branches borne on juvenile crusts that are rarely found. A detailed investigation of these juvenile stages has allowed the discovery of their reproductive features. Sexual reproduction of P. calcareum, the type-species of the genus, is described here for the first time and thus gives fundamental data for the generic definition. On the floor of the female conceptacle, a set of carpogonial branches is formed. Each fertilized carpogonium then fuses with the supporting cell of the carpogonial branch, which is also its auxiliary cell. A small fusion cell is thus formed, which produces upwards a small gonimoblast reduced to a short chain of carposporangia. In a mature conceptacle, the surface of the fertile floor thus appears entirely covered with small gonimoblasts. In the male conceptacle, mature spermatangia produced on the floor are typically dendroid; those produced on the walls are of a more simple type. The organization of the asexual conceptacle is briefly reviewed. The reproduction of L. corallioides is also newly described and compared with that previously reported for L. muelleri, the type-species of the genus.Key words: Corallinales, Phymatolithon, Lithothamnion, sexual reproduction, generic definition.


1968 ◽  
Vol 16 (2) ◽  
pp. 197 ◽  
Author(s):  
RN Baldock ◽  
HBS Womersley

Two species of southern Australian marine algae have been previously placed in Bornetia. One, B. binderiana (Sonder) Zanardini, shows the generic features of the type species from Europe (B. secundiflora), and an additional species, B. tenuis, is also described for the genus. Study of the type and the above two Australian species shows that Bornetia is characterized by subdichotomous filaments of elongate cells, a 5-6(-8)-celled fertile axis developing procarps successively and also non-functional pseudocarpogonia, an involucre produced from the lower cells of the fertile axis, and a large stellate fusion cell; and by the production of tetrasporangia and spermatangial heads in condensed clusters in which the terminal branch cells curve around the cluster as an involucre. The other Australian species, B. ? Meredithiana J. Agardh, has procarps confined to the subterminal cell of a 3-celled fertile axis, and after fertilization sterile cells associated with the procarp produce an inner involucre around the carposporophyte, which has a massive fusion cell. Sessile polysporangia are borne in condensed lateral branch clusters. A new genus, Involucrana, is proposed for this species. Its relationships are probably with Sphondylothamnion, which also differs from other known Ceramiaceae in having a similar inner involucre.


Zootaxa ◽  
2019 ◽  
Vol 4613 (2) ◽  
pp. 327
Author(s):  
LAURENCE A. MOUND ◽  
DESLEY J. TREE

The genus Xylaplothrips is re-diagnosed, 11 species are listed as appropriately included in this genus of which three are new combinations from Haplothrips (X. acaciae; X. collyerae; X. gahniae). A further six species are listed as incertae sedis within Xylaplothrips and a key is provided to the four species of this genus known from Australia including X. anarsius sp.n. The genus Mesandrothrips is recalled from synonymy with Xylaplothrips, and a list is provided of 20 appropriately included species of which 14 are new combinations from Xylaplothrips (M. caliginosus; M. clavipes; M. darci; M. dubius; M. emineus; M. flavitibia; M. flavus; M. inquilinus; M. montanus; M. pictipes; M. pusillus; M. reedi; M. subterraneus; M. tener), and one is a new combination from Haplothrips (M. inquinatus). A key is provided to 10 species of this genus known from Australia, including three species transferred from Haplothrips, together with M. austrosteensia sp.n., M. googongi sp.n., M. kurandae sp.n., M. lamingtoni sp.n. and M. oleariae sp.n. The type species, M. inquilinus, is widespread across Southeast Asia as an invader of thrips galls, and Haplothrips darci Girault based on a single female from Queensland is considered closely related. 


Zootaxa ◽  
2018 ◽  
Vol 4524 (5) ◽  
pp. 567 ◽  
Author(s):  
PAWEŁ JAŁOSZYŃSKI

Based on examination of type species, the subgenera Palaeoconnus Franz and Heterotetramelus Franz are removed from Euconnus Thomson. Adults of Palaeoconnus have the prosternum bearing a subtriangular prosternal process and their metacoxae are contiguous, which exclude this taxon from Euconnus. Palaeoconnus is transferred to Sciacharis Broun as subgenus and redefined. The lectotype is designated for its type species, Scydmaenus brevipes Sharp. Sciacharis andicola (Franz), previously treated as incertae sedis within Sciacharis, is placed in Palaeoconnus. Heterotetramelus is also excluded from Euconnus, on the basis of the mesoventrite lacking the mesoventral intercoxal process and the contiguous metacoxae. Heterotetramelus stat. n. is elevated to genus rank and redefined, and the lectotype is designated for its type species, Euconnus caledonicus Franz. Moreover, the newly defined Heterotetramelus is reclassified to include four subgenera: Heterotetramelus s. str. (with seven species distributed in New Caledonia), Sciacharoides Jałoszyński, stat. n. (reduced from genus; with three Australian species); Australosciacharoides subgen. n. (with only one Australian species transferred from Sciacharoides); and Tamborinus subgen. n. (also with one Australian species transferred from Sciacharoides). 


Zootaxa ◽  
2021 ◽  
Vol 5016 (4) ◽  
pp. 503-522
Author(s):  
M. B. MALIPATIL

The Australian species of the small heterogastrid genus Parathyginus Scudder, 1957 have been reviewed, resulting in the establishment of the junior subjective synonymy of P. doddi (Distant, 1918) with P. signifer (Walker, 1872), and the description of two new species, P. australis sp. nov. and P. acuminatus sp. nov. A redescription of the genus is provided with emphasis on male and female genitalia characters, along with a key to all included Australian species. Male genitalia, particularly the details of the aedeagus, have been rarely studied in this genus or for that matter the family Heterogastridae particularly due to the difficulty in inflating the inflatable sections. In this study, therefore, an attempt was made to fully inflate and describe the aedeagus of all the species included in this contribution, as well as of Heterogaster urticae (Fabricius, 1775), the type species of the oldest genus Heterogaster Schilling, 1829, of the family Heterogastridae.  


1990 ◽  
Vol 38 (5) ◽  
pp. 535 ◽  
Author(s):  
MN Hutchinson ◽  
SC Donnellan ◽  
PR Baverstock ◽  
M Krieg ◽  
S Simms ◽  
...  

The phylogenetic relationships of the Australian scincid lizards currently assigned to the genus Leiolopisma have been examined by quantitative micro-complement fixation (MC'F) comparisons of serum albumin. The results of these comparisons do not support the monophyly implicit in these species' current congeneric status, but suggest instead that the Australian species of Leiolopisma belong to several distinct phyletic lineages within the Eugongylus group. These findings are supported by several sets of non-biochemical characters, including features of scalation, osteology and karyotype. None of the Australian species shares a close relationship with the type-species of Leiolopisrna (L. telfairii), and so a new taxonomic arrangement is proposed which distributes them among the following genera: Bartleia, gen. nov. (jigurru); Bassiana, gen. nov. (duperreyi, platynotum and trilineata); Cautula, gen. nov. (zia); Niveoscincus, gen. nov. (coventryi, greeni, metallicus, microlepidotus, ocellatus, orocryptus, palfreymani and pretiosus); and Pseudemoia Fuhn, 1967 (baudini, entrecasteauxii Group 1; entrecasteauxii Group 2, rawlinsoni and spenceri). Preliminary comparisons suggest that other Leiolopisma species, from New Caledonia, Lord Howe I. and New Zealand, belong to phyletic lineages which are distinct from any of the Australian 'Leiolopisma' and from the type-species.


1979 ◽  
Vol 57 (7) ◽  
pp. 783-786
Author(s):  
P. Ramachar ◽  
G. Bhagyanarayana

Ramakrishnania is described as a new genus of rust fungi with R. ixorae n.sp as the type species. Distinct features of this genus are the indeterminate growth of the basal cell and the formation of two-celled puccinioid teliospores on septate simple pedicels bilaterally on the elongating basal cell.


2021 ◽  
Author(s):  
◽  
Phil J. Sirvid

<p>The New Zealand Thomisidae (crab spiders) are represented in New Zealand by two subfamilies (Stephanopinae and Thomisinae) and were used as a model group to test two competing theories on the origins of the New Zealand spider fauna. The New Zealand thomisids are also given their first full taxonomic revision. The two origin models essentially represent species radiations following recent dispersal or ancient vicariance events. Modern distribution data suggested that the stephanopines are poor dispersers and may provide evidence demonstrating a long period of separation from Australia; while in contrast, thomisines are known to be excellent dispersers. Maximum Likelihood and Bayesian analyses of cytochrome c suboxidase subunit I (COI), 28S ribosomal RNA (28S), histone H3 (H3), NADH dehyrogenase 1 (ND1) data and a combined genetic dataset was undertaken. Results indicate New Zealand stephanopines and thomisines form distinct endemic groups separate from sampled Australian species and appear to have separated from them around 5-6 million years ago. Additionally, genetic data from this study showed i) colour variations are not indicative of cryptic species; ii) previously described species are genetically distinct; iii) several suspected new species are also genetically distinct; iv) the relatively recent establishment of two Australian stephanopines and the occurrence of similar COI haplotypes in disjunct locations suggest that the dispersal ability of stephanopines is greater than previously thought and that radiation following colonization from Australia is a plausible explanation for the current diversity of the New Zealand thomisid biota. The taxonomic revision raises the number of described species from eight to eleven based on a combination of morphological and genetic data. In the stephanopines, Bryantymella Gen. nov. is erected to contain the type species Bryantymella angularis (Urquhart, 1885) comb. nov. as well as B. angulata (Urquhart, 1885) comb. nov., B. thorini sp. nov. and B. brevirostris sp. nov. Two Australian species, Sidymella longipes (Koch, 1874) and S. trapezia (Koch, 1874), are also recorded for New Zealand. Sidymella benhami (Hogg, 1910) is considered to be a junior synonym of Bryantymella angulata (Urquhart, 1885). In the thomisines, all species are now included in the previously monotypic genus Cymbachina Bryant, 1933. The genus now encompasses the type species C. albobrunnea (Urquhart, 1893), C. ambara (Urquhart, 1885) comb. nov., C. albolimbata (L. Koch, 1893) comb. nov., C. sphaeroides (Urquhart, 1885) comb. nov. and D. urquharti sp. nov. Synema suteri Dahl, 1907 is regarded as a junior synonym of C. ambara (L. Koch 1893). All previously described species are redescribed to a modern standard and sexes for some species are described for the first time. Three new species are described. Photographs of adults and diagnostic genitalic characters are included, as are diagnostic keys and updated synonymic, geographic and biological information. Overall, this study indicates that New Zealand thomisids appear to have split from their Australian relatives some 5-6 million years ago and taken in concert with the recent establishment of two Australian stephanopine species, it appears that dispersal to New Zealand by Australian colonists and subsequent radiation into endemic New Zealand forms is a plausible explanation for the current state of the fauna. Genetic and morphological data are mutually supporting and in concert have helped inform the first taxonomic revision ever undertaken for this family in New Zealand.</p>


1978 ◽  
Vol 26 (4) ◽  
pp. 841
Author(s):  
RJ Raven

Two new genera, Plesiothele and Bymainiella, are erected to receive all the Australian species of the subfamily Hexathelinae, which now comprises four genera, including Hexathele with 20 species from New Zealand, and Scotinoecus with two species from South America. Plesiothele is a monotypic Tasmanian genus, type-species Hexathele fentoni Hickman, 1936. Bymainiella comprises 12 new species: B. boycei, B. boydi, B. brindabella, B. cannoni, B. grayi, B. lugubris, B. monteithi, B. montisbossi, B. otwayensis, B. polesoni, B. tubrabucca and B. variabilis; also B. montana (Hickman, 1927), and B. terraereginae (Raven, 1976), the latter being the type-species. The typespecies of Scotinoecus, S. cinereopilosus, is redescribed, and keys to the genera of the subfamily Hexathelinae, and to the Bymainiella species, are given. Two new indices are introduced to overcome the problem of bilateral variability. Bymainiella is believed to be the sister group of Scotinoecus.


1999 ◽  
Vol 65 (7) ◽  
pp. 3121-3128 ◽  
Author(s):  
E. Virginia Armbrust

ABSTRACT An intriguing feature of the diatom life cycle is that sexual reproduction and the generation of genetic diversity are coupled to the control of cell size. A PCR-based cDNA subtraction technique was used to identify genes that are expressed as small cells of the centric diatom Thalassiosira weissflogii initiate gametogenesis. Ten genes that are up-regulated during the early stages of sexual reproduction have been identified thus far. Three of the sexually induced genes, Sig1, Sig2, andSig3, were sequenced to completion and are members of a novel gene family. The three polypeptides encoded by these genes possess different molecular masses and charges but display many features in common: they share five highly conserved domains; they each contain three or more cysteine-rich epithelial growth factor (EGF)-like repeats; and they each display homology to the EGF-like region of the vertebrate extracellular matrix glycoprotein tenascin X. Interestingly, the five conserved domains appear in the same order in each polypeptide but are separated by variable numbers of nonconserved amino acids. SIG1 and SIG2 display putative regulatory domains within the nonconserved regions. A calcium-binding, EF-hand motif is found in SIG1, and an ATP/GTP binding motif is present in SIG2. The striking similarity between the SIG polypeptides and extracellular matrix components commonly involved in cell-cell interactions suggests that the SIG polypeptides may play a role in sperm-egg recognition. The SIG polypeptides are thus important molecular targets for determining when and where sexual reproduction occurs in the field.


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