A NEW METHOD OF CYSTOCARP DEVELOPMENT IN THE RED ALGAL GENUS CALLOPHYLLIS (KALLYMENIACEAE) FROM CHILE1

Traditional studies suggest that the Kallymeniaceae can be divided into two major groups, a nonprocarpic Kallymenia group, in which carposporophyte formation involves an auxiliary cell branch system separate from the carpogonial branch system, and a procarpic Callophyllis group, in which the carpogonial branch system gives rise to the carposporophyte directly after fertilization. Based on our phylogenetic studies and unpublished observations, the two groups each contain both procarpic and nonprocarpic genera. Here, we describe a new method of reproductive development in Callophyllis concepcionensis Arakaki, Alveal et Ramírez from Chile. The carpogonial branch system consists of a supporting cell bearing both a three‐celled carpogonial branch with trichogyne and two‐lobed “subsidiary” cells. After fertilization, large numbers of secondary subcortical and medullary cells are produced. Lobes of the carpogonial branch system cut off connecting cells containing enlarged, presumably diploid nuclei that fuse with these secondary vegetative cells and deposit their nuclei. Derivative enlarged nuclei are transferred from one vegetative cell to another, which ultimately cut off gonimoblast initials that form filaments that surround the central primary medullary cells and produce carposporangia. The repeated involvement of vegetative cells in gonimoblast formation is a new observation, not only in Callophyllis, but in red algae generally. These results call for a revised classification of the Kallymeniaceae based on new morphological and molecular studies.     

COMPARATIVE MORPHOLOGY AND TAXONOMIC STATUS OF GRACILARIOPSIS (GRACILARIALES,RHODOPHYTA)1

The vegetative organization and reproductive development of Gracilariopsis lemaneiformis (Bory) Dawson, Acleto et Foldvik [including Gracilaria sjoestedtii Kylin] were investigated. Our observations on spermatangial development and post-fertilization features establish that Gracilariopsis Dawson is distinct at the generic level from Gracilaria Greville, and ice propose the resurrection of Gracilariopsis Dawson as a result. Spermatangial parent cells of Gracilariopsis are superficial, initiated in pairs or groups of three by concavo-convex longitudinal and transverse divisions. Each spermatangial parent cell cuts off a single, colorless spermatangium distally by a transverse division. The female reproductive apparatus consists of a supporting cell that bears a two-celled carpogonial branch flanked by two sterile branches, as in Gracilaria. Likewise, up to six sterile cells fuse with the carpogonium after fertilization to produce a primary fusion cell that generates the gonimoblasts; however, a secondary fusion cell is absent. Inner gonimoblast cells unite with cytologically modified cells of the inner pericarp by means of secondary pit-connections. Tubular nutritive cells are absent. The gonimoblast consists of a central sterile tissue interconnected throughout by secondary pit-connections surmounted by a fertile layer composed of carposporangia aligned in straight chains. The distribution of Gracilariopsis is extended to Western Europe.     

PROPOSAL OF THE GRACILARIALES ORD. NOV. (RHODOPHYTA) BASED ON AN ANALYSIS OF THE REPRODUCTIVE DEVELOPMENT OF GRACILARIA VERRUCOSA1

The mode of division of vegetative cells, formation of spermatangial parent cells, initiation of the carpogonial branch apparatus, and formation of tetrasporangial initials are homologous developmental processes that are documented for the first time in the type species of the economically important family Gracilariaceae, Gracilaria verrucosa (Hudson) Papenfuss from the British Isles. G. verrucosa is characterized by a supporting cell of intercalary origin that bears a 2-celled carpogonial branch flanked by two sterile branches, direct fusion of cells of sterile branches onto the carpogonium, formation of an extensive carpogonial fusion cell through the incorporation of additional gametophytic cells prior to gonimoblast initiation, gonimoblast initials produced from fusion cell lobes, schizogenous development of the cytocarp cavity, inner gonimoblast cells producing tubular nutritive cells that fuse with cells of the pericarp or floor of the cystocarp, absence of cytologically modified tissue in the floor of the cystocarp, and carposporangial initials produced in clusters or irregular chains. Spermatangial parent cells are generated in flaments from intercalary cortical cells that line an intercellular space forming a ‘pit’ or ‘conceptacle’. Tetrasporangial initials are transformed from terminal cells derived through division of an outer cortical cell. Tetrasporangia are cruciately divided. The Gracilariaceae is removed from Gigartinales and transferred to the new order Gracilariales. Their closest living relatives appear to be agarophytes belonging to the Gelidiales and Ahnfeltiales.     

VEGETATIVE AND REPRODUCTIVE MORPHOLOGY OF EUCHEUMA ISIFORME (SOLIERIACEAE,GIGARTINALES, RHODOPHYTA)1

Eucheuma isiforme (C. Agardh) J. Agardh exhibits a combination of vegetative and reproductive features that distinguish it from other critically studied genera in the Solieriaceae. The development of the multiaxial thallus, emphasizing the arrangement of periaxial cells around each axial file; presence of reproductive nemathecia that contain carpogonial branches and auxiliary cells; and post-diploidization stages, including gonimoblast and pericarp initiation, stages of fusion cell formation, and carposporophyte development are described and illustrated for the first time in this species. The vegetative and reproductive features observed in E. isiforme are not diagnostic of any of the recently erected tribes in the Solieriaceae. Eucheuma appears most closely related to the Indian Ocean genus, Sarconema.     

Studies of the Liagoraceae (rhodophyta) of Western Australia: Gloiotrichus fractalis gen. et sp. nov. and Ganonema helminthaxis sp. nov.

Two new taxa of Liagoraceae (Nemaliales) are described from Western Australia. Gloiotrichus fractalis gen. et sp. nov. has been collected from 3–20 m depths at the Houtman Abrolhos, Western Australia. Plants are calcified, extremely lubricous, and grow to 17 cm in length. Carpogonial branches are straight, 6 or 7 cells in length, arise from the basal or lower cells of cortical fascicles, and are occasionally compound. Branched sterile filaments of narrow elongate cells arise on the lower cells of the carpogonial branch prior to gonimoblast initiation, at first on the basal cells, then on progressively more distal cells. Following presumed fertilisation the carpogonium divides transversely, with both cells giving rise to gonimoblast filaments. The distal cells of the carpogonial branch then begin to fuse, with fusion progressing proximally until most of the cells of the carpogonial branch are included. As fusion extends, the filaments on the carpogonial branch are reduced to the basal 2 or 3 cells. The gonimoblast is compact and bears terminal carposporangia. Spermatangial clusters arise on subterminal cells of the cortex, eventually displacing the terminal cells. The sequence of pre- and post-fertilisation events occurring in the new genus separates it from all others included in the Liagoraceae, although it appears to have close affinities with the uncalcified genus Nemalion. Ganonema helminthaxis sp. nov. was collected from 12 m depths at Rottnest Island, Western Australia. Plants are uncalcified and mucilaginous, the axes consisting of a few (< 10) primary medullary filaments, each cell of which gives rise to a cortical fascicle at alternate forks of the pseudodichotomies borne on successive medullary cells. Subsidiary (adventitious) filaments and rhizoids comprise the bulk of the thallus. Carpogonial branches are straight, (3-)4(-6) cells in length, arise on the basal 1–4 cells of the cortical fascicles, and are frequently compound. Carposporophytes develop from the upper of two daughter cells formed by a transverse division of the fertilised carpogonium. Ascending and descending sterile filaments girdle the carpogonial branch cells and arise mostly on the supporting cell prior to fertilisation. Ganonema helminthaxis is the first completely non-calcified member of the genus, and its reproductive and vegetative morphology supports the recognition of Ganonema as a genus independent from Liagora. Liagora codii Womersley is a southern Australian species displaying features of Ganonema, to which it is transferred.     

MORPHOLOGY OF THE SUBANTARCTIC RED ALGA CENACRUM SUBSUTUM GEN. ET SP. NOV. (RHODYMENIALES) FROM MACQUARIE ISLAND1

The red alga Cenacrum subsutum gen. et sp. nov. is described from material collected at Macquarie Island in the subantarctic between November 1977 and February 1978. The habit and carposporophyte development are similar to members of the family Rhodymeniaceae (Rhodymeniales), but certain vegetative features are unique. The frond is a variously incised or lobed foliose blade with hollow apices above and a medulla which becomes progressively filled basipetally with ingrowing rhizoidal filaments. Details of carpogonial branch, auxiliary cell, connecting cell and gonimoblast anatomy are given, as well as observations on the habitats and distribution of the species.     

LEACHIELLA PACIFICA,GEN. ET SP. NOV., A NEW PARASITIC RED ALGA FROM WASHINGTON AND CALIFORNIA

Leachiella pacifica, gen. et sp. nov., a marine alloparasitic red alga is described from Washington and California. Several species of Polysiphonia and Pterosiphonia are hosts for this parasite. The thallus is a white, multiaxial, unbranched pustule with rhizoidal filaments that ramify between host cells, forming numerous secondary pit connections with host cells. All reproductive structures develop from outer cortical cells. Tetrasporocytes, situated on stalk cells, undergo simultaneous, tetrahedral cleavage to form tetraspores. Spermatia are formed continuously by oblique cleavages of the elongate spermatial generating cells. This results in spermatial clusters consisting of 4–8 spermatia in an alternate arrangement. Carposporophyte development is procarpial. The carpogonium is part of a six-celled branch including a sterile cell that is formed by the basal cell. The carpogonial branch is attached laterally to an obovate supporting cell that also forms an auxiliary cell, presumably formed prior to fertilization. After fertilization the carpogonium temporarily fuses with the auxiliary cell apparently to transfer the diploid nucleus and initiate further fusion with the subtending supporting cell to form an incipient fusion cell. The auxiliary cell portion of this fusion cell divides to form gonimoblast initials that continue to divide, forming gonimoblast filaments whose terminal cells differentiate into carpospores. The remainder of the fusion cell enlarges by continual fusion with adjacent vegetative cells. The resultant carposporophyte consists of a basal, multinucleate fusion cell supporting a hemispherical cluster of gonimoblast filaments with terminally borne carpospores. Vegetatively, Leachiella resembles several other parasitic red algae but it is clearly separated by the procarp, carposporophyte development and structure, and tetrasporocyte cleavage.     

REPRODUCTIVE DEVELOPMENT OF THE PARASITIC RED ALGA GARDNERIELLA TUBERIFERA (SOLIERIACEAE,GIGARTINALES)1

Examination of the reproductive morphology of the adelphoparasitic red alga Gardneriella tuberifera Kylin reveals that this monotypic genus is correctly placed in the family Solieriaceae (Gigartinales), to which its host Agardhiella gaudichaudii (Montagne) Silva et Papenfuss also belongs. Gardneriella is multiaxial, nonprocarpic and has an inwardly directed, three-celled carpogonial branch. The large, reniform uninucleate auxiliary cell is distinct prior to and after fertilization. It is diploidized by an unbranched, multicellular connecting filament which lacks pit connections. One or two connecting filaments arise from each fertilized carpogonium. From the diploidized auxiliary cell, the gonimoblast initial is cut off obliquely toward the interior of the thallus. The cells of the gonimoblast fuse with adjacent unpigmented vegetative cells of Gardneriella and pigmented cells of the host. These cells become incorporated into the developing cystocarp and, from those of Gardneriella, additional short chains of gonimoblast cells arise. The mature cystocarp is placentate, radiately lobed, and lacks a surrounding involucre. Carposporangia are borne in short chains and the unpigmented carpospores are released upon the dissolution of outer vegetative cells. No ostiole is present. Gardneriella appears to be most closely related to the placentate solieriacean genera Agardhiella, Sarcodiotheca, and Meristiella and therefore this genus should be placed in the tribe recently erected for these taxa, the Agardhielleae.     

STUDIES IN SOME FOLIOSE RED ALGAE OF THE PACIFIC COAST. III. DUMONTIACEAE,WEEKSIACEAE, KALLYMENIACEAE1

The female reproductive structures and their development, and the vegetative structure are studied in 17 species of red algae in the Cryptonemiales (Rhodophyceae). Three genera, Weeksia, Constantinea, and the type species of Leptocladia, are removed from the Dumontiaceae to a newly created family, the Weeksiaceae, because of differing postfertilization events leading to the development of the gonimoblast from a cell of the carpogonial branch. Three genera of Dumontiaceae are studied: Pikea, including P. californica, the type species, and Pikea robusta a newly described species; Dilsea californica, and a newly described species of Neodilsea, a genus heretofore known only from the northwestern Pacific. Two transfers are made from the genus Leptocladia, 1 to Farlowia, as F. conferta, and 1 to Rhodophyllis (Gigartinales) as R. peruviana. Three species in the Kallymeniaceae are redescribed: Kallymenia pacifica, a rare and nearly unknown species from southern California and adjacent Pacific Mexico; K. norrisii from central California; and K. oblongifructa from Washington, Oregon, and northern California.     

A MORPHOLOGICAL STUDY OF HOMMERSANDIA MAXIMICARPA GEN. ET SP. NOV. (KALLYMENIACEAE,RHODOPHYTA) FROM THE NORTH PACIFIC1

A new foliose red alga, common subtidally from British Columbia to the Aleutian Islands, is described and given the name Hommersandia maximicarpa. The lobed perennial thallus, which can reach a height of 23 cm, is distinguished by its vegetative structure and by its unique pattern of nonprocarpic carposporophyte development. In transverse section, the blades consist of a narrow filamentous medullary layer sandwiched on either side by large ellipsoidal subcortical cells and a thin outer cortex. The monocarpogonial branch and auxiliary cell systems of the female plants are typical of many members of the Kallymeniaceae. However, after the carpogonialfusion cell forms, a distinctive developmental pattern begins. The connecting filaments radiate outward into the surrounding tissue, branch abundantly, and become septate. They then contact, in addition to auxiliary cells, many small moniliform accessory branches. These branches appear to act as initiation points for the gonimoblast filaments. The large diffuse carposporophytes produced are unknown in any other member of the Cryptonemiales. The vegetative and reproductive anatomy of Hommersandia is compared to other Kallymeniaceae, and similar patterns of postfertilization development are examined in the Rhodophyta.     

Consideration of the order Cryptonemiales and the families Nemastomataceae and Furcellariaceae (Gigartinales,Rhodophyta) in light of the morphology of Adelophyton corneum (J. Agardh) gen. et comb. nov. from southern Australia

A new red algal genus is described, based on the southern Australian Chaetangium corneum J. Agardh. It is reproductively unique in that while the auxiliary cell is intercalary in an adventitious filament, a defining character of the order Cryptonemiales, the vegetative structure, carpogonial branches, connecting filaments and gonimoblast development seem strongly allied to lower families of the Gigartinales. Although its predominantly thallus-inward gonimoblast development is characteristic of the gigartinalian family Furcellariaceae, it is suggested that the new alga should be placed in the Nemastomataceae and that this family exhibits features which, in an ancient algal stock, could theoretically have given rise to the lower cryptonemialian and higher gigartinalian lines. The possible relationships between the Nemastomataceae, Furcellariaceae and Solieriaceae are discussed, and some seemingly primitive features of the Nemastomataceae are enumcrated.     

SYSTEMATIC REVISION OF THE GENERA LIAGORA AND IZZIELLA (LIAGORACEAE,RHODOPHYTA) FROM TAIWAN BASED ON MOLECULAR ANALYSES AND CARPOSPOROPHYTE DEVELOPMENT,WITH THE DESCRIPTION OF TWO NEW SPECIES1

Some Liagora and Izziella distributed in Taiwan display a wide range of morphological variation and can be difficult to distinguish. To clarify species concepts, we applied DNA sequence analyses and examined carposporophyte development in detail. These studies revealed two new species, which are described herein as Izziella hommersandii sp. nov. and Izziella kuroshioensis sp. nov. I. kuroshioensis superficially resembles Izziella formosana and Izziella orientalis in that its involucral filaments subtend rather than surround the lower portion of the gonimoblast mass (= Izziella type) and a fusion cell is formed from cells of the carpogonial branch, but it can be separated by differences in the cell numbers and branching pattern of the involucral filaments, as well as thallus morphology. In contrast to other species that also bear short lateral branchlets, I. hommersandii is unique in possessing a mixture of short and long involucral filaments, a phenomenon not reported before. The length of the involucral filaments is species specific among species of Izziella and contrasts to the behavior of the involucral filaments after fertilization in species such as “Liagora”setchellii [= Titanophycus setchellii comb. nov.], in which the filaments completely envelop the gonimoblast. In addition, the cells of the carpogonial branch in Titanophycus do not fuse after fertilization to form a fusion cell. Thus, a combination of characters with respect to the behavior of the carpogonial branch and the involucral filaments after fertilization is very useful for delineating species boundaries in Izziella and for separating Titanophycus from Izziella and Liagora.     

STUDIES IN THE HELMINTHOCLADIACEAE. II. TRICHOGLOEOPSIS

Abbott , Isabella A. (Hopkins Marine Station of Stanford U., Pacific Grove, Calif.), and Maxwell S. Doty . Studies in the Helminthocladiaceae. II. Trichogloeopsis . Amer. Jour. Bot. 47(8) : 632–640. Illus. 1960.—A new genus, Trichogloeopsis , in the Helminthocladiaceae of the red algal order Nemalionales is described. Its diagnostic features are the possession of sterile rhizoids produced by the gonimoblast, and the fact that the carpogonial branch is a modified vegetative filament. The type species of the genus is T. hawaiiana from the Hawaiian Islands. Two species of Liagora, L. pedicellata from the Bahamas and L. mucosissima from the Ryukyus, are transferred to the new genus.     

Studies on Metamastophora (Corallinaceae,Rhodophyta). I. M. flabellata (Sonder) Setchell: Morphology and anatomy

A morphological-anatomical study of Australian populations of Metamastophora flabellata (Sonder) Setchell, the type species of Metamastophora (Corallinaceae, Rhodophyta), has revealed that the primarily erect or ascending non-geniculate thallus possesses a dorsi-ventral organization of tissues. All conceptacles are uniporate and arise dorsally. Two distinct vegetative meristems occur: an apical primary meristem from which hypothallial cells are produced basipetally and a sub-epithallial secondary meristem which generates perithallial cells basipetally and secondary epithallial cells acropetally. Primary epithallial cells arise from divisions of subapical hypothallial cells. In younger parts, tissues are produced only dorsal to the hypothallium; in veins and stipes, tissue production occurs both dorsal and ventral to the hypothallium. Mature tetrasporic conceptacles contain peripheral tetrasporangia with zonately divided contents and a central sterile columella. Gametic conceptacles produce fertile tissue across the entire conceptacle chamber floor. After fertilization, the zygotic nucleus or a derivative is transferred (presumably) to an auxiliary cell through cells of the carpogonial branch; no tubular transfer siphon develops. Mature fusion cells are composed of the amalgamated supporting cells of carpogonial branches and are initiated from a single supporting cell which functions as an auxiliary cell. Unbranched 3–4 celled gonimoblast filaments arise from the fusion cell, do not become connected to other cells, and produce terminal carposporangia. Results from this study have led to a redefinition of hypothallium and perithallium in relation to meristems rather than substrate. In addition, carposporophyte ontogeny in the Corallinaceae is considered in terms of the presumed mode of transfer of the zygotic nucleus to the fusion cell, the extent of fusion cell development, and gonimoblast filament production in relation to auxiliary cells and fusion cells.     

ONTOGENY OF SEXUAL CONCEPTACLES IN A SPECIES OF BOSSIELLA (CORALLINACEAE)1

The first evidence of conceptacle formation in male and female plants of Bossiella californica ssp. Schmittii is the secretion of a cap below the epithallium. Subsequent development involves the disintegration of the upper enucleate parts of cortical cells below the center of the cap concomitant with the growth of tissue surrounding these cells. Protoplasts in the lower parts of these cortical cells recover and become initials of reproductive cells. Differentiation of each initial in female plants results in a supporting cells bearing 1 or 2, 2-celled carpogonial filaments, and in male plants results in a basal cell bearing 2 or 3 spermatangial mother cells which bud off spermatangia. Following fertilization, supporting cells fuse and form a broad, thin fusion cell from the upper surface of which gonimoblast (carposporangial) filaments arise.     

REPRODUCTION AND LIFE HISTORY OF THE RED ALGA GALAXAURA OBLONGATA (NEMALIALES,GALAXAURACEAE)1

Culture and morphological studies showed that Galaxaura oblongata (Ellis et Solander) Lamouroux has a triphasic life history with conspicuous gametophytes and small filamentous tetrasporophytes. Development of male and female reproductive structures is very similar and both begin with the enlargement of a terminal cell of a filament branch occupying a normal vegetative position within the apical pit of a thallus branch. In male thalli this modified branch forms a conceptacle in which spermatangia are produced. In female thalli, this modified branch forms a three-celled carpogonial branch consisting of a carpogonium, hypogynous cell and basal cell. Filament branches from the basal cell form a pericarp and the gonimoblast develops directly from the carpogonium. Carposporangia are produced in conceptacles which resemble the male conceptacles. About the time the first carposporangia are produced, the carpogonium, hypogynous cell and basal cell form a large fusion cell. Released carpospores germinate in a unipolar or bipolar manner and form small filamentous thalli. Under short day conditions, cruciate tetrasporangia are produced in small clusters. Tetraspores germinate similarly to carpospores and also form small filamentous thalli. Under low nutrient conditions, small cylindrical thalli develop on the filaments and these appear similar to gametophytes collected in nature.     

OBSERVATIONS ON THE DEVELOPMENT OF THE CARPOSPOROPHYTE OF SCINAIA PSEUDOJAPONICA YAMADA ET TANAKA (NEMALIALES,CHAETANGIACEAE)1

The development of the carposporophyte of Scinaia pseudojaponica Yamada et Tanaka is described for the first time. The carpogonial branch is 3-celled. Before fertilization the hypogynous cell divides into a group of 4 cells. Concurrently the cell beneath the hypogynous cells also produces initials which, following fertilization, develop into branched filaments that envelop the carposporophyte. After fertilization the gonimoblast initial is produced laterally from the basal part of the carpogonium. Carposporangia are produced in chains from the free ends of the gonimoblast filaments which grow toward the surface of the thyllus. A very thick pericarp surrounds the mature carposporophyte.     

A re-examination of the morphology and reproduction of Nothocladus lindaueri (Batrachospermales, Rhodophyta)

The vegetative morphology and reproduction of the freshwater rhodophyte Nothocladus lindaueri Skuja [=Batrachospermum lindaueri (Skuja) Necchi et Entwisle] were examined by light and electron microscopy. It was confirmed that this alga has a typical batrachospermalean pit plug with two cap layers, the outer one of which is domed. During elongation of hair cells, the primary wall is broken, forming a basal collar. Hair cells have a single nucleus and abundant Golgi bodies, en-doplasmic reticula (ER) and vesicles. Dividing apical cells of the fascicles have a nucleus with art adjacent zone of exclusion, the latter containing a single polar ring. Branched trichogynes and fertilized carpogonia are shown for the first time in this species. Carpogonial branch and involucral cells contain a prominent axial nucleus, proplastids, ER and vesicles. The pit plugs disintegrate among these cells leaving open pit connections. Carpogonia have plentiful mitochondria and vesicles. The wall at the trichogyne apex is thickened and densely stained. The carposporophyte centre consists of a mass of fusion cells with open pit connections, and indeterminate gonimoblast filaments arise from this mass. The combination of a symmetrical carpogonial base, a carposporophyte centre consisting of a mass of fusion cells, and exclusively indeterminate gonimoblast filaments appears to be unique among the members of the Batrachospermaceae. The specimen of N. lindaueri contains epiphytic filaments of Audouinella meiospora producing both spermatangia and monosporangia. Spermatium formation in N. lindaueri remains unknown.     

Why one species in New Zealand,Pugetia delicatissima (Kallymeniaceae,Rhodophyta), should become two new genera,Judithia gen. nov. and Wendya gen. nov.

Blade-forming red algae occur worldwide and, prior to DNA sequencing, had been notoriously difficult to identify and classify, especially when lacking critical reproductive features. This, coupled in New Zealand with many longstanding assumptions that taxa were identical to non-New Zealand species or genera, resulted in many misapplied names. Pugetia delicatissima R.E. Norris, an endemic New Zealand blade-forming species of the family Kallymeniaceae, is actually comprised of one existing and one new species belonging to two distinct genera, as established by our phylogenetic analyses of DNA sequences from the rbcL gene. Analyses of combined rbcL and LSU genes showed that neither is closely related to the generitype of Pugetia, the northern-eastern Pacific, P. fragilissima Kylin. We propose the names Judithia and Wendya for these two newly revealed genera. In addition to diagnostic rbcL and LSU sequences, Judithia is morphologically and anatomically characterized by rounded to oblong blades that do not taper basally at the stipe, loosely aggregated surface cortical cells and cystocarps lacking both a pericarp and an ostiole, all features observed in the holotype of P. delicatissima. Wendya, in contrast, is characterized by blades that taper both apically and basally, compactly arranged surface cortical cells and cystocarps that have both a pericarp and a distinct ostiole. The two genera also are distinguished from one other, as well as from Pugetia by features of pre- and post-fertilization development, including the number of subsidiary cells produced on carpogonial and auxiliary branch systems, whether subsidiary cells in the carpogonial branch system fuse with the supporting cell or not, and the site of origin of gonimoblast cells. Although small in area, New Zealand hosts ten of the 27 currently recognized genera in the Kallymeniaceae and is the southern-hemisphere region of greatest generic diversification in this family.     

CHARACTERIZATION OF MYHOGRAMME LNIDA, MYRIOGRAMMEAE TRIB. NOV (DELESSEIUACEAE, FWODOPHYTA)

The Myriogramme group of Kylin was found to contain two distinct clusters of genera that merit recognition at the tribal level. In this paper, we establish the tribe Myriogrammae based on a study of the type species of Myriogramme, M. livida, from the Southern Hemisphere. The Myriogrammae is characterized by 1) marginal and diffuse intercalary meristems; 2) nuclei arranged in a ring bordering the side walls of vegetative cells; 3) microscopic veins absent; 4) procarps scattered, formed opposite one another on both sides of the blade posterior to one or more vegetative pericentral cells (cover cells) and consisting of a carpogonial branch, a one-/to two-celled lateral sterile group and a one-celled basal sterile group; 5) auxiliary cell diploidized by a connecting cell cut off posteriolaterally from the fertilized carpogonium; 6) gonimoblast initial cut off distally from the auxiliary cell, generating one distal and one to two lateral gonimoblast filaments that branch in the plane of the expanding cystocarp cavity and later fuse to from an extensive, branched fusion cell; 7) spermatangial and tatrasporangial sori formed inside the margin on both sides of the blade by resumption of meristematic activity; and 8) tetrasporangia produced primarily from the central cells. The Myriogrammae currently includes Myriogramme Kylin , Gonimocolax Kylin , Haraldiophyllum A. Zinova , Hideophyllum A. Zinova, and a possible undescribed genus from Pacific North and South America. Genera are separated based primarily on features of gonimoblast and carposporangial development .