TRIGONOCARPUS LEEANUS,A NEW SPECIES FROM THE MIDDLE PENNSYLVANIAN OF SOUTHERN ILLINOIS

A new species of Trigonocarpus Brongniart is described from the level of the Herrin (No. 6) Coal (Carbondale Formation, Kewanee Group) at Carterville, Illinois. The seed is three dimensionally preserved by authigenic cementation and exhibits a well preserved nucellar cast, integument and micropylar region. The specimen represents the largest pteridosperm compression-impression seed collected in North America and measures 10 cm from the apex of the micropyle to the chalazal end, and at least 5 cm in breadth. Trigonocarpus leeanus sp. n. is compared to the remaining forty-three taxa within the genus, and specifically with Trigonocarpus grandis Lesquereux, the one species with dimensions approaching it. An emended diagnosis, with designation of a lectotype, is presented for Trigonocarpus grandis. Correlation of the features displayed by Trigonocarpus leeanus sp. n. and the petrified taxa within Pachytesta Brongniart is attempted.     

A new diatom (Bacillariophyceae) genus with two new species from New Mexico,USA

A new diatom (Bacillariophyceae) genus and two new species are described from the arid region of the North American southwest. The new genus, Playaensis, and new species, P. circumfimbria and P. furtiva, are distinguished by frustule morphology and autecology. Playaensis possesses unique, narrowly lunate longitudinal ribs bordering the raphe and spathulate spines, but their evolutionary relationship to known genera is unclear. In Payton Lake, New Mexico, P. circumfimbria and P. furtiva are rare in the diatom community, and their geographic and geological extent are not known, but they may be restricted to alkaline, slightly saline lakes of the region.     

PALEOZOIC SEED STUDIES: A NEW PENNSYLVANIAN PACHYTESTA FROM SOUTHERN ILLINOIS

Pachytesta stewartii, a new species found in Middle Pennsylvanian coal ball deposits in southern Illinois, is 2.5 cm long and approximately 1.5 cm in width at its greatest diameter. Commissured ribs are pronounced near the apex and progressively less distinct toward the base. The integumentary system is delimited into 3 regions: outer sarcotesta, middle sclerotesta, and thin endotesta. Conspicuous in the new species is a pronounced basal extension with an enclosed chamber that may be the result of decomposition of thin-walled parenchyma cells. Relationships with other species and possible significance of the chalazal chamber are discussed.     

MICROGAMETOPHYTE DEVELOPMENT IN THE PALEOZOIC SEED FERN FAMILY CALLISTOPHYTACEAE

Well-preserved stages of microgametophyte development are described from pollen produced by the Paleozoic seed fern family Callistophytaceae. Microgametophyte development in both the Middle Pennsylvanian pollen organ Idanothekion and Upper Pennsylvanian Callandrium involved the initial production of an axial row of at least three small prothallial cells proximally and a large embryonal cell distally. The arrangement and form of these cells is like that present in some extant genera of the Pinaceae. The prothallial cells were relatively large in comparison with extant gymnosperms, occupying the entire region of the cap-pus, and were apparently all primary. Evidence is presented that in Callandrium further development involved an anticlinal division of the large distal cell (antheridial initial) into a small generative cell contained within a larger tube cell. Previously described microgametophytes of the late Paleozoic order Cordaitales are reinterpreted and are shown to consist of an embryonal cell and three to four discoidal prothallial cells in an axial row like that of the Callistophytaceae. Microgametophytes thus far described from the Paleozoic are remarkably modern in appearance and provide no evidence to support the generally held view that the seed plant microgametophyte is an extremely reduced sexual phase that has arisen through the loss of almost all of the vegetative cells and the sterile outer cells of the antheridium. Evidence to support or refute this view will depend upon the discovery of microgametophytes from older groups of seed plants than those for which they are now known.     

How much seed remains in the soil after a fire?

Soil seed banks that persist after a fire are important in fire-prone habitats as they minimise the risk of decline or local extinction in plants, should the fire-free interval be less than the primary juvenile periods of the species. In two common woody plant genera (Acacia and Grevillea) in southeastern Australia, we examined the size and location of the residual seed bank after fire across areas of varying seedling densities at three locations in comparison to the distribution of seeds in the soil at an unburnt site. We found viable dormant seeds remaining in the soil after fire (evidence of residual soil seed bank). A significantly lower proportion of seeds remained in the top 5 cm of soil than at 5–10 cm or 10–15 cm soil depths, independent of seedling density or plant genus. This was due to greater germination, and possibly some seed mortality, near the soil surface. Reduced germination below 5 cm was probably due to the reduced efficacy of the fire cues that break seed dormancy, a declining ability of seeds to emerge successfully from such depths, and the lower abundance of seeds in the soil at such depths. The magnitude of the residual seed bank was similar across 0–5, 5–10 and 10–15 cm soil depths in Acacia suaveolens. For two Grevillea species, most residual seeds were at 0–5 and 5–10 cm. The residual soil seed bank in the top 10 cm of soil after fire varied across sites with estimates of 0, 19 and 27% in G. speciosa and 23, 35, and 55% in A. suaveolens. At two sites, both species had similar residual seed bank sizes, while at a third, there were large differences between the species (0–55%). The observed patterns imply that the fire-related cues that break seed dormancy generally declined with soil depth. For Acacia, seed dormancy is broken by heat shock, a fire-cue that declines with soil depth. Some 250 species (approx 15% of the fire-prone flora) in the region are thought to have dormancy broken by heat shock. For Grevillea, where seed dormancy is broken by the interaction of smoke and heat shock, at two sites, we suggest three possibilities: (i) the smoke cue declined with soil depth; (ii) both heat and smoke are obligatory for breaking seed dormancy; or (iii) the cues may be independent and additive and below the zone of soil heating, only a proportion of available seeds had dormancy broken by smoke alone. At a third site (no residual seed bank detected) the smoke cue was predicted not to have declined with soil depth. Up to 900 species (just under half the fire-prone flora) in the study region are thought to have seed dormancy broken by the interaction of heat and smoke during the passage of a fire.     

Implications of Seedling Emergence to Site Restoration following Bauxite Mining in Western Australia

Seedling emergence of 12 selected northern jarrah (Eucalyptus marginata Donn ex Smith) forest species were investigated to assist Alcoa of Australia Ltd. in maximizing the establishment of topsoil species in rehabilitated bauxite mining sites. The species, which encompassed a range of seed weights (0.024 mg to 87 mg), plant families, seed-storage types, life forms, and germination requirements, were placed on the soil surface and at depths of 1, 2, 5, 10, and 15 cm under controlled conditions in a glasshouse. Ability to emerge from deep burial was found to depend on seed size for species that annually release their seed to the topsoil but not for species that store their seed on the plant. All selected species were capable of emerging from 2 cm depth of burial, but eight of the 12 species were either unable to emerge from 5 cm or showed a significant reduction in emergence from 5 cm depth of burial compared to optimally buried seed. This group included two small-seeded species, Stylidium calcaratum and Chamaescilla corymbosa; the major forest dominant, Eucalyptus marginata; the serotinous canopy-borne seed of Hakea amplexicaulis; and the wind-dispersed seed of Xanthorrhoea gracilis. A few seeds of the legume species Kennedia coccinea, Acacia pulchella, and Bossiaea aquifolium established seedlings from depths of 15 cm. Currently, Alcoa removes the upper 15 cm of topsoil separately from the underlying soil prior to the commencement of mining. This topsoil is respread at a similar depth following mining as part of the rehabilitation procedure. It is recommended that Alcoa continue to strip topsoil to a depth of 15 cm but investigate the option of re-spreading topsoil onto rehabilitated pits at a shallower depth to maximize establishment via the soil seed bank.     

An African twin to the Brazilian Calamopleurus (Actinopterygii: Amiidae)

A new species of amiid fish, Calamopleurus africanus sp. nov., is described on the basis of fragmentary material from ?Albian Kem Kem beds of southern Morocco. The new species shows several derived characters of the genus Calamopleurus such as ossified dermopterotic ribs, an inferred loose association between the dermosphenotic and the skull roof, a gular plate with a scalloped posterior margin, and a hyomandibular with a very long posterior (opercular) process. It differs from the type species in the proportions of the frontals, supramaxilla and gular. The distribution of Calamopleurus and some other Lower Cretaceous fishes is discussed in the context of the presumed adjacency of west Africa and eastern Brazil during much of the Mesozoic.     

PETRIFIED PLANTS FROM THE UPPER MISSISSIPPIAN OF NORTH AMERICA. I: THE SEED RHYNCHOSPERMA GEN. N.

Petrified seeds of Upper Mississippian age (Chester Series) are described from sediments from northwestern Arkansas. Specimens of Rhynchosperma quinnii gen. et sp. n. are radially symmetrical and range in length from 1.2 to 2.2 cm and 1.0 to 1.3 cm at the greatest diameter. The seeds are ovate with a tapered apex having 8–10 integumentary ribs and a broadly rounded chalaza. The integument is two-parted, consisting of an outer presumably soft tissue with secretory canals and an inner layer constructed of longitudinally oriented thick-walled cells. Nucellus and integument are confluent, but they diverge near the seed midlevel with the free portion of the nucellus forming a dome-shaped pollen-receiving structure. Additional features such as vasculature and the structure of well-preserved megagametophytes are described. The petrified specimens are compared with taxa instituted for casts and impressions which include Rhynchogonium and Boroviczia. The ovulate versus cupulate nature of these genera which has remained uncertain until now appears to be settled in favor of an ovular identity.     

PINUS BUCHANANII,A NEW SPECIES BASED ON A PETRIFIED CONE FROM THE OLIGOCENE OF WASHINGTON

A silicified seed cone of Oligocene age from the Olympic Peninsula of Washington represents a new species of Pinus. The cone was about 8 cm long and 3 cm at its widest diameter in the living condition. Its scale apices are thickened and each has a dorsal umbo. Internal cone construction confirms the assignment of the new species to Pinus and suggests affinity with the subsections Australes and Ponderosae of the section Pinus, subgenus Pinus. The cone is peculiar in having a stout bract trace that is slightly concave on its adaxial side and in having resin canals that diverge from the axial secretory system toward the bract but constrict markedly and terminate before entering the bract.     

Hoya somadeeae sp. nov. (Apocynaceae,Asclepiadoideae) Thailand and lectotypification of Hoya wrayi

A new species from evergreen montane forests of Thailand, Hoya somadeeae Rodda & Simonsson is here described and illustrated. The new species may be superficially confused with the Peninsular Malaysia endemic H. wrayi King & Gamble, but is clearly separated from it by the very elongated peduncles, up to 20 cm long, the revolute corollas, and outer processes of corona lobes with a membranaceous basal appendage. Morphological affinities between the new species and other Hoya species from Thailand and neighbouring Myanmar and Peninsular Malaysia are discussed.     

Impatiens quadriloba sp. nov. (Balsaminaceae) from Sichuan,China

Impatiens quadriloba K. M. Liu et Y. L. Xiang sp. nov. collected from the Siguniang Mountains Nature Reserve in northwestern Sichuan, China, is described and illustrated. The seed‐coat and pollen morphology of the new species are described and diagnostic morphological characters that distinguish the new species from the related I. falcifer Hook. f. are discussed.     

Morphology and anatomy of the Cephalocereus columna-trajani cephalium: why tilting?

The morphology and anatomy of the Cephalocereus columna-trajani flowering region was described and compared with data on other species. The vegetative and reproductive regions were described in detail. The results showed that after the flowering region is differentiated, morphological changes take place which are correlated with anatomical changes. The flowering region in this species is termed a lateral cephalium because of its reduced interareolar space, increased areole size and abundant long bristles and trichomes in the areoles. Periderm development near the apical meristem, lack of chlorenchyma and a delay in xylem fiber differentiation are also traits characteristic of a lateral cephalium. The lateral cephalium of C. columna-trajani shared the same combination of morpho-anatomical characters with its sister taxon, C. senilis, except for the number of ribs in the cephalium. Both species survive in high temperature environments and their cephalium faces north; however, only C. columna-trajani tilts, thus we hypothesize that incorporation of fewer ribs associated with periderm development in the cephalium contributes to stem tilting.     

PICEA WOLFEI,A NEW SPECIES OF PETRIFIED CONE FROM THE MIOCENE OF NORTHWESTERN NEVADA

Several silicified ovulate cones from the late middle Miocene (Barstovian) represent a new species, Picea wolfei Crabtree. This is the second species of Picea for which structurally preserved seed cones are known to be reported from the Tertiary. The cones are 5.0–8.0 cm long and 1.5–2.0 cm at their greatest diameter. Ovuliferous scales are inserted helically around the cone axis and are recurved at their point of divergence. Each scale is broadly obovate to spatulate with a rounded apex and bore two seeds adaxially. The bract subtending the scale is 4.5–7.3 mm long and is fused to the scale for 1.4–2.0 mm. Each bract has an inflated keel-like base which projects abaxially between the seeds of adjacent scales. The fossil cones superficially resemble those of the extant Picea breweriana, yet differ from them anatomically. The new species also resembles Picea lahontense, a fossil compression from the Miocene Trout Creek Flora of south-central Oregon, but the different modes of preservation preclude meaningful comparison. Picea diettertiana, the only structurally preserved fossil cone of this genus previously described, is quite dissimilar in that it lacks a sclerotic pith.     

<Emphasis Type="Italic">Lecomtedoxa plumosa</Emphasis> (Sapotaceae), a new tree species from Korup National Park,Cameroon

Summary   Lecomtedoxa plumosa Burgt (Sapotaceae), a new tree species from the southern part of Korup National Park in Cameroon, is described and illustrated. The flowers show the characteristics of the genus Lecomtedoxa: for example the staminodes are free and placed alternately to the stamens and corolla lobes. The leaves of the new species are clearly different from other Lecomtedoxa spp., but they look similar to the leaves of Gluema ivorensis, especially to those of the collections from Cameroon. In total 26 trees ≥ 10 cm dbh were found. The largest trees found were 36 m high and 74 cm dbh. The trees grow in primary rain forest, in clusters of up to 10 trees on 2 ha, mixed with many other tree species. The seed dispersal is ballistic. The conservation status of the species is assessed as Endangered, EN D.     

Pterygiella trichosepala (Orobanchaceae), sp. nov. from Yunnan,southwest China

Pterygiella trichosepala (Orobanchaceae) is described and illustrated as a new species endemic to Yunnan, southwest China. It grows in calcareous grasslands or scrubs at elevations of 2000–2600 m a.s.l. This new species is closely related to P. nigrescens Oliv., but clearly differs from the latter by being pilose–hirsute throughout, with stems simple or rarely branched, 10–30 cm tall, and leaves 10–20 mm long and 3–6 mm wide (with L/W ratio 3.5–5.0), racemose inflorescences, and calyx 13–20 mm long and 8–13 mm in diameter; moreover its seed micromorphological features are significantly different from those of P. nigrescens.     

The Iberian Peninsula: ancient history of a hot spot of mite harvestmen (Arachnida: Opiliones: Cyphophthalmi: Sironidae) diversity

The Iberian Peninsula represents a hot spot of cyphophthalmid (mite harvestman) disparity, with four of the eight genera currently recognized in the family Sironidae represented in the region – a generic diversity and morphological disparity not found in any other region of the World so far. From these, two genera (Iberosiro and Odontosiro) are monotypic, and are restricted to the western side of the peninsula. Parasiro is restricted to the north‐east region, from the Catalonian Coastal Ranges and both sides of the Eastern Pyrenees, in areas where the annual rainfall surpasses 1000 mm, and mostly restricted to areas with Paleozoic and Variscan rocks, with other species of the genus extending to Corsica, Sardinia, and the Italian Peninsula. A second species of the genus Paramiopsalis, Paramiopsalis eduardoi sp. nov. from Fragas do Eume, is described here along with a re‐diagnosis of the genus. Paramiopsalis species, together with Odontosiro, inhabit the north‐west corner of the Iberian Peninsula, an area with some of the highest recorded annual rainfall, and with Paleozoic rocks from the Iberian Massif or Variscan granitoid rocks. A phylogenetic analysis of the members of the family Sironidae using four molecular markers, despite not including all of the Iberian genera, clearly shows the non‐monophyly of the Iberian Cyphophthalmi, indicating that the Iberian Peninsula is home to multiple ancient lineages of mite harvestmen. The two Paramiopsalis species form a sister clade to the Balkan genus Cyphophthalmus, whereas Parasiro constitutes the first lineage of the sironids represented.     

Aristolochia bhamoensis sp. nov. (Aristolochiaceae) and a diagnostic key to all known A. subgen. Siphisia species from Myanmar

Aristolochia bhamoensis from Myanmar is here described and illustrated. This new species is morphologically similar to A. faviogonzalezii (confined to northern Vietnam) and A. cathcartii (growing in the Himalayan region) but is distinguished from the latter two species by having a cream‐white upper part of the perianth tube, with visible purple ridges, a trumpet‐shaped limb, 5.0–5.5 cm diameter, inner surface of limb lobes densely covered with dark‐purple bristles, a nearly circular mouth, 3.2–3.5 cm wide, upper half of throat being dark‐purple to blackish, without striations or dots, and lower half purple, with conspicuous white striation. Morphological characters such as a 3‐lobed gynostemium and a 3‐lobed limb support a placement of the new species in the subgenus Siphisia. A diagnostic key is provided to the seven Siphisia species known from Myanmar.     

Penicillium yugoslavicum sp. nov., isolated from sunflower seeds (Helianthus annuus L.) in Yugoslavia

A new species of Penicillium Link ex Fries is described and illustrated. It was recovered from sunflower seed (Helianthus annuus L.) in Yugoslavia. It clearly differs from all species of the genus described so far and is, therefore, proposed as a new taxon: Penicillium yugoslavicum sp. nov.     

SILICIFIED PINUS REMAINS FROM THE MIOCENE OF WASHINGTON

Silicified leaves, dwarf shoots, pollen cones, and seed cones of Pinus from a Late Miocene chert bed within the Yakima Basalt Formation near Yakima, Washington are interpreted as coming from a single new species, P. foisyi. The needles and dwarf shoots are those of a three-needle pine. The needles contain two to four medial resin canals, a biform hypodermis, and endodermal cells with uniformly thickened walls. The pollen cones are ellipsoidal and about 1 cm long, and many contain bisaccate pollen grains. The seed cones are at least 6 cm long and are slightly asymmetrical. The cone axis has a broad sclerotic outer cortex, and the seed wing extends from a thick parenchymatous base. The scale apex bears a conspicuously swollen projection. The foliage and seed cones are identifiable with the Subgenus Pinus, Section Pinus, Subsection Oocarpae independently of one another, and together indicate a fossil species related to the modem Californian closed cone pines. Pinus foisyi represents one of the earliest occurrences of cone asymmetry associated with this group. However, cone serotiny characteristic of the modem species appears to have evolved after the Late Miocene.     

A new species of Cycas (Cycadaceae) from Karnataka,India

Cycas swamyi Singh & Radha, sp. nov. (Cycadaceae) is described and illustrated from Karnataka, India. This new species has been confused with Cycas circinalis L., which is found in the Western Ghats. However, on the basis of its habit, characteristic isotomous‐type dichotomous branching, pinnae anatomy, mega‐ and microsporophyll morphology and seed anatomy, it has been segregated from C. circinalis and is described here as a new species. The distribution and conservation status are also discussed. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 430–435