Floral development and anatomy of two species of Aechmea (Bromeliaceae, Bromelioideae)

Abstract Aechmea (Bromeliaceae) is a large genus with controversial systematics and distinct flower shapes and pollinators. We explored floral anatomy and development in two Aechmea spp. belonging to different subgenera to contribute useful information on reproductive biology and taxonomy. We examined floral buds using scanning electron and light microscopy to characterize the development of septal nectaries, petal appendages, ovules, stamens and carpels. In A. gamosepala, we confirmed that the petal appendages develop late, whereas in A. correia-araujoi they develop earlier during floral development. Petal appendage formation included positional changes, possibly affecting floral attributes and visitation by insects, rather than vertebrates. Nectar is released through three basal orifices distally on the ovary, and here we document the link between the nectary region, through discrete canals, upward to the conduplicate lobes of the wet stigma. Improved understanding of the floral development and morphology of Aechmea may help to explain the existence of polymorphic flowers in this genus and may have implications for studies on interactions with pollinators and systematics.

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Infection of Schistocerca gregaria by the fungus Metarhizium anisopliae: Cellular reactions in the integument studied by scanning electron and light microscopy

Journal of Invertebrate Pathology ◽

10.1016/0022-2011(88)90096-1 ◽

1988 ◽

Vol 52 (1) ◽

pp. 9-17 ◽

Cited By ~ 34

Author(s):

S.G.S. Gunnarsson

Keyword(s):

Light Microscopy ◽

Metarhizium Anisopliae ◽

Schistocerca Gregaria ◽

Electron And Light Microscopy ◽

Scanning Electron

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Chrysophycean stomatocysts from the postglacial sediments of a High Arctic lake

Canadian Journal of Botany ◽

10.1139/b88-160 ◽

1988 ◽

Vol 66 (6) ◽

pp. 1117-1128 ◽

Cited By ~ 27

Author(s):

Katharine E. Duff ◽

John P. Smol

Keyword(s):

Species Composition ◽

Light Microscopy ◽

High Arctic ◽

Ellesmere Island ◽

Arctic Lakes ◽

Ecological Research ◽

Stratigraphic Analysis ◽

Morphological Detail ◽

Electron And Light Microscopy ◽

Scanning Electron

Twenty-six chrysophycean stomatocyst morphotypes were described from the postglacial sediments of a small, rock basin lake near Baird Inlet, Ellesmere Island. Scanning electron and light microscopy were used to classify the stomatocysts, following the guidelines of the International Statospore Working Group. None of the stomatocysts could be related with certainty to the chrysophyte species that produced them, but sufficient morphological detail is present in most of the stomatocysts to allow for taxonomic differentiation. A stratigraphic analysis of the dominant stomatocyst morphotypes revealed that chrysophyte species composition changed most markedly during the lake's early development but then remained relatively constant. This study demonstrated that chrysophycean stomatocysts provide useful paleoecological information in High Arctic lakes, but further taxonomic and ecological research is required to fully exploit these microfossils.

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Variation in Penicillium and Aspergillus Conidia in Relation to Preparatory Techniques for Scanning Electron and Light Microscopy

Modern Concepts in Penicillium and Aspergillus Classification ◽

10.1007/978-1-4899-3579-3_4 ◽

1990 ◽

pp. 39-48 ◽

Cited By ~ 3

Author(s):

P. Staugaard ◽

R. A. Samson ◽

M. I. van der Horst

Keyword(s):

Light Microscopy ◽

Electron And Light Microscopy ◽

Scanning Electron

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Setal morphology of grooming appendages in blue crabs Callinectes sapidus Rathbun, 1896 and stone crabs Menippe mercenaria (Say, 1818) (Decapoda: Brachyura: Portunidae, Menippidae)

Journal of Crustacean Biology ◽

10.1093/jcbiol/ruz032 ◽

2019 ◽

Vol 39 (4) ◽

pp. 357-377

Author(s):

Jen L Wortham ◽

Stephanie Pascual

Keyword(s):

Light Microscopy ◽

Functional Morphology ◽

Sensory Input ◽

Callinectes Sapidus ◽

Time Budget ◽

Activity Level ◽

Body Regions ◽

Electron And Light Microscopy ◽

Insight Into ◽

Scanning Electron

Abstract Respiration, sensory input, movement, and molting rely on crustacean body regions being free of fouling. While the grooming appendages of shrimps have been described, few studies have documented the functional morphology of grooming appendages in brachyuran crabs. Because shrimps and brachyurans have very different body morphology and grooming behaviors, their grooming setae may vary. The morphology of grooming appendages of blue (Callinectes sapidusRathbun, 1896) and stone (Menippe mercenaria (Say, 1818)) crabs were investigated to gain better insight into their efficiencies in decreasing fouling. Callinectes sapidus is an active swimmer, migrates through currents across estuaries, spends less time grooming, and is exposed to more environmental variants in contrast to M. mercenaria, which has a lower activity level and spends more time grooming. To compensate for this higher activity level and lower grooming time budget, C. sapidus was predicted to have more setal types on its grooming appendages as compared to M. mercenaria. Thirteen different body appendages/regions involved in grooming are described in both species by using scanning electron and light microscopy. We documented the morphology, presence or absence of setal patches, and types of setae in 104 different grooming appendages and groomed body regions. Of 25 types of setae, nine are unique to C. sapidus, rejecting the hypothesis that C. sapidus have more diverse grooming setae. Menippe mercenaria has denser setal patches and less fouling than C. sapidus. Nine new setal types are described. Fouling, setal diversities, and functions that correspond to grooming behaviors are discussed.

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