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40-424: See text. Selaginella , also known as spikemosses or lesser clubmosses is a genus of lycophyte . It is usually treated as the only genus in the family Selaginellaceae , with over 750 known species. This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having spores of two types . They are sometimes included in an informal paraphyletic group called

80-612: A circus as a musician to earn some money, and finally obtained work curating the private botanical collection of the painter Charles Willson Peale . He joined the American Philosophical Society , contributed to its Transactions , and resumed his collecting with the sponsorship of the French minister, Pierre Adet , a scientist in his own right. Palisot's collecting trips in the United States ranged from

120-462: A group of vascular plants that include the clubmosses . They are sometimes placed in a division Lycopodiophyta or Lycophyta or in a subdivision Lycopodiophytina . They are one of the oldest lineages of extant (living) vascular plants; the group contains extinct plants that have been dated from the Silurian (ca. 425 million years ago). Lycophytes were some of the dominating plant species of

160-577: A pamphlet in which he accused English philanthropists of sinister motives in supporting this project. On the eve of the Haitian Revolution he also went to the United States to ask the aid of the government in reducing the Haitian slaves to obedience. On his return from this useless mission in June 1793, he found the island in insurrection. An uprising by slaves resulted in the town being burnt, as

200-439: A single vascular trace (vein), rather than the much more complex megaphylls of other vascular plants. The extinct genus Asteroxylon represents a transition between these two groups: it has a vascular trace leaving the central protostele, but this extends only to the base of the enation. See § Evolution of microphylls . Zosterophylls and extant lycophytes are all relatively small plants, but some extinct species, such as

240-612: A small scale-like outgrowth called a ligule at the base of the upper surface. The plants are heterosporous with spores of two different size classes, known as megaspores and microspores. Unusual for the lycopods, which nearly always have microphylls with a single unbranched vein, the microphylls of a few Selaginella species contain a branched vascular trace. Under dry conditions, some species of Selaginella can survive dehydration. In this state, they may roll up into brown balls and be uprooted, but can rehydrate under moist conditions, become green again and resume growth. This phenomenon

280-540: Is known as poikilohydry , and poikilohydric plants such as Selaginella bryopteris are sometimes referred to as resurrection plants . There is no evidence of whole genome duplication in Selaginella's evolutionary history. Instead they have gone through tandem gene duplications, which is particularly noticeable in genes relevant for desiccation tolerance. Some scientists still place the Selaginellales in

320-750: The Elateridae , were later sent by Pierre François Marie Auguste Dejean to Frederick DuCane Godman and Osbert Salvin at the British Museum of Natural History to be included in the Biologia Centrali-Americana . Specimens were also sent by Louis Alexandre Auguste Chevrolat to Neervoort van de Poll of the Netherlands , and these in turn were bequeathed to the British Museum of Natural History , but none of Palisot's specimens have been found there. The third volume of

360-526: The Articulatae , since his genus Didiclis/Gymnogynum was based on Selaginella plumosa . He also described the genus Diplostachyum to include a group of species similar to Selaginella apoda . Spring inflated the genus Selaginella to hold all selaginelloid species four decades later. Phylogenetic studies by Korall & Kenrick determined that the Euselaginella group, comprising solely

400-467: The Carboniferous period, and included the tree-like Lepidodendrales , some of which grew over 40 metres (130 ft) in height, although extant lycophytes are relatively small plants. The scientific names and the informal English names used for this group of plants are ambiguous. For example, "Lycopodiophyta" and the shorter "Lycophyta" as well as the informal "lycophyte" may be used to include

440-558: The Jardin Botanique at Geneva . The herbarium at the Philadelphia Academy of Natural Sciences has sheets that are marked "Beauv.", but show plants native to India, a place never visited by Palisot. Therefore, Palisot must have incorporated specimens from other collectors, which would explain the strange origin of some of the insects from his collection. Horn & Kahle (1937) state that some of Palisot's beetles,

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480-463: The Lepidodendrales , were tree-like, and formed extensive forests that dominated the landscape and contributed to the formation of coal . In the broadest circumscription of the lycophytes, the group includes the extinct zosterophylls as well as the extant (living) lycophytes and their closest extinct relatives. The names and ranks used for this group vary considerably. Some sources use

520-587: The Ohio River in the west to Savannah, Georgia , in the south. He made several valuable discoveries, including that of a new species of rattlesnake , and he passed several months among the Creek and Cherokee Indians. He was elected a member of the American Philosophical Society , to which he communicated a part of his observations. Palisot finally received word from Paris that his citizenship had been restored, and began planning his return to Europe, especially

560-722: The Transactions of the Philosophical Society of Philadelphia contains a paper by him on cryptogamic plants, and the fourth, one on a new plant of Pennsylvania (the Heterandra raniformis ) and on a new species of rattlesnake, etc. His "Description du mur naturel dans la Caroline du Nord" appears in vol. viii of the Annales du muséum d'histoire naturelle (Paris, 1811), and was reprinted in Warren's Description of

600-555: The Zosterophyllopsida by the possession of microphylls . Some zosterophylls, such as the Devonian Zosterophyllum myretonianum , had smooth stems (axes). Others, such as Sawdonia ornata , had flap-like extensions on the stems ("enations"), but without any vascular tissue. Asteroxylon , identified as an early lycopodiopsid, had vascular traces that extended to the base of the enations. Species in

640-482: The euphyllophytes , such as ferns , gymnosperms and flowering plants . They are defined by two synapomorphies : lateral rather than terminal sporangia (often kidney-shaped or reniform), and exarch protosteles , in which the protoxylem is outside the metaxylem rather than vice versa. The extinct zosterophylls have at most only flap-like extensions of the stem ("enations") rather than leaves, whereas extant lycophyte species have microphylls , leaves that have only

680-535: The " fern allies ". The species S. moellendorffii is an important model organism . Its genome has been sequenced by the United States Department of Energy 's Joint Genome Institute . The name Selaginella was erected by Palisot de Beauvois solely for the species Selaginella selaginoides , which turns out (with the closely related Selaginella deflexa ) to be a clade that is sister to all other Selaginellas , so any definitive subdivision of

720-419: The "zosterophylls" comprise a paraphyletic group, ranging from forms like Hicklingia , which had bare stems, to forms like Sawdonia and Nothia , whose stems are covered with unvascularized spines or enations. The genus Renalia illustrates the problems in classifying early land plants. It has characteristics both of the non-lycophyte rhyniophytes – terminal rather than lateral sporangia – and of

760-1295: The broad Stachygynandrum group. In 2023, Zhou & Zhang suggested that the genus should be broken up into 19 different genera. subgenus Selaginella subgenus Boreoselaginella section Megalosporum section Myosurus section Lyallia section Articulatae section Lepidophyllae section Homeophyllae subgenus Pulviniella section Tetragonostachyae section Heterostachys section Auriculatae section Homostachys S. braunii subclade S. willdenowii subclade S. pennata subclade S. pervillei subclade S. siamensis subclade S. delicatula subclade section Plagiophyllae section Circinatae section Ascendentes section Proceres section Pallescentes section Austroamericanae section Heterophyllae Selaginoides Séguier 1754 Boreoselaginella (Warburg 1900) Zhang & Zhou 2023 Afroselaginella Zhang & Zhou 2023 Megaloselaginella Zhang & Zhou 2023 Ericetorum (Jermy 1986) Zhang & Zhou 2023 Gymnogynum Palisot de Beauvois 1804 Lepidoselaginella Zhang & Zhou 2023 Bryodesma Soják 1992 Pulviniella (Zhang & Zhou 2015) Zhang & Zhou 2023 Lycophyte The lycophytes , when broadly circumscribed , are

800-487: The bulk of species. The first major attempt to define and subdivide the group was by Palisot de Beauvois in 1803–1805. He established the genus Selaginella as a monotypic genus, and placed the bulk of species in Stachygynandrum . Gymnogynum was another monotypic genus, but that name is superseded by his own earlier name of Didiclis . This turns out, today, to be a group of around 45–50 species also known as

840-493: The class Lycopodiopsida (often misconstructed as "Lycopsida"). Some modern authors recognize three generic divisions of Selaginella : Selaginella , Bryodesma Sojak 1992 , and Lycopodioides Boehm 1760 . Lycopodioides would include the North American species S. apoda and S. eclipes , while Bryodesma would include S. rupestris (as Bryodesma rupestre ). Stachygynandrum is also sometimes used to include

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880-716: The classification of lycopods, notably the Lycopodiaceae and Selaginellaceae . After finishing his studies he was appointed advocate to the Parlement of Paris in 1772, and afterward receiver general . He then devoted himself to the study of natural history, especially botany. In 1786 he set out to found a colony at Oware at the mouth of the Niger River in what is today called Nigeria . Palisot merged specimens from there with collections from neighbouring Benin . At intervals he sent material back to France, including

920-494: The colony. Palisot became so debilitated with yellow fever that in 1788 he was placed on a slave ship bound for Haiti where he had an uncle in Cap-français , and where he made the acquaintance of another French botanist, Guillaume Silvestre Delahaye . He recovered and returned to his collecting. He was admitted into the colonial assembly and the superior council, opposed the abolition of the slave trade , and in 1790 wrote

960-525: The extant lycophytes and their closest extinct relatives. The consensus classification produced by the Pteridophyte Phylogeny Group classification in 2016 (PPG I) places all extant (living) lycophytes in the class Lycopodiopsida . There are around 1,290 to 1,340 such species. For more information on the classification of extant lycophytes, see Lycopodiopsida § Classification . A major cladistic study of land plants

1000-402: The extinct zosterophylls or to exclude them. Lycophytes reproduce by spores and have alternation of generations in which (like other vascular plants) the sporophyte generation is dominant. Some lycophytes are homosporous while others are heterosporous . When broadly circumscribed , the lycophytes represent a line of evolution distinct from that leading to all other vascular plants ,

1040-461: The first liverwort specimens to be collected from Africa and sent to Europe. Among his collections is a leaf bearing the type specimens of two epiphytic leafy liverworts, one of which has never again been collected. However, most of his collection was destroyed when the British invaded the colony and razed the trading post where his material was kept. An epidemic of yellow fever spread through

1080-470: The freighting of his collections. Dogged by misfortune, these collections were lost in a shipwreck off Nova Scotia in 1798. Palisot returned to France in the same year. Using material that had survived all the disasters, as well as his sketches, he published a number of booklets on plants and insects, between 1805 and 1821. Griffin (1932, 1937) supplies the date of publication for each booklet which consisted of five to six plates, each depicting six or nine of

1120-501: The genus Leclercqia had fully vascularized microphylls. These are considered to be stages in the evolution of microphylls. Palisot de Beauvois Palisot collected insects in Oware, Benin , Saint Domingue , and the United States, from 1786 to 1797. Trained as a botanist, Palisot published a significant entomological paper entitled, "Insectes Receuillis en Afrique et en Amerique". Together with Frederick Valentine Melsheimer , he

1160-487: The insects described in the text, and it is through these sketches, rather than by specimens, that Palisot's species are often identified. Palisot invented a new method of classification for insects, and proposed another for quadrupeds. He observed the details of the reproductive organs in mosses, and, as the existence of these organs was denied, he confirmed his first researches by new observations. Few of Palisot's specimens have survived. His botanical specimens were sent to

1200-421: The names "Lycopodiophyta" or the shorter "Lycophyta" to include zosterophylls as well as extant lycophytes and their closest extinct relatives, while others use these names to exclude zosterophylls. The name "Lycopodiophytina" has also been used in the inclusive sense. English names, such as "lycophyte", "lycopodiophyte" or "lycopod", are similarly ambiguous, and may refer to the broadly defined group or only to

1240-416: The presence of more than two protosteles. Each stele is made up of diarch (having two strands of xylem) and exarch (growing outward in) xylems . The steles are connected with the cortex by means of many tube-like structures called trabeculae , which are modified endodermal cells with casparian strips on their lateral walls. The stems contain no pith. In Selaginella , each microphyll and sporophyll has

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1280-477: The present. Selaginella species are creeping or ascendant plants with simple, scale-like leaves ( microphylls ) on branching stems from which roots also arise. The stems are aerial, horizontally creeping on the substratum (as in Selaginella kraussiana ), sub-erect ( Selaginella trachyphylla ) or erect (as in Selaginella erythropus ). The vascular steles are polystelic protosteles . Stem section shows

1320-455: The same group as the extant orders. Different sources use varying numbers and names of the extinct orders. The following phylogram shows a likely relationship between some of the proposed Lycopodiopsida orders. Lycopodiales † Drepanophycales Selaginellales † Lepidodendrales † Pleuromeiales Isoetales Within the broadly defined lycophyte group, species placed in the class Lycopodiopsida are distinguished from species placed in

1360-527: The species into separate genera leaves two taxa in Selaginella , with the hundreds of other species in new or resurrected genera. Selaginella occurs mostly in the tropical regions of the world, with a handful of species to be found in the arctic-alpine zones of both hemispheres. Fossils assignable to the modern genus are known spanning over 300 million years from the Late Carboniferous to

1400-721: The specimens that were labelled from America, were from Africa, and vice versa. He created type localities in America for species such as Dynastes hercules (L.), well outside the natural range. Palisot's expeditions were described inter alia by Chase (1925) and Merrill (1937) and a summary is provided here to explain the uncertain origins of his material. Palisot trained as a lawyer but pursued postgraduate studies in botany under Jean-Baptiste Lestiboudois in Lille and Antoine Laurent de Jussieu in Paris. He also did important early work on

1440-514: The type species, Selaginella selaginoides and a closely related Hawaiian species, Selaginella deflexa , is a basal and anciently diverging sister to all other Selaginella species. Beyond this, their study split the remainder of species into two broad groups, one including the Bryodesma species, the Articulatae , section Ericetorum Jermy and others, and the other centered on

1480-608: The zosterophylls – kidney-shaped sporangia opening along the distal margin. A rather different view is presented in a 2013 analysis by Hao and Xue. Their preferred cladogram shows the zosterophylls and associated genera basal to both the lycopodiopsids and the euphyllophytes, so that there is no clade corresponding to the broadly defined group of lycophytes used by other authors.  basal groups  Adoketophyton Zosterophyllopsida     Lycopsida  basal groups  Yunia , Dibracophyton euphyllophytes Some extinct orders of lycophytes fall into

1520-517: Was his uncle's home and Palisot's collections. Palisot was imprisoned, but later freed under order of deportation. Because of his title, Palisot understandably was reluctant to return to France in the aftermath of the Revolution . He boarded a ship bound for the United States and on the voyage was robbed of his remaining worldly goods and arrived in Philadelphia totally destitute. He joined

1560-511: Was one of the first entomologists to collect and describe American insects. He described many common insects and suggested an ordinal classification of insects. He described many Scarabaeidae as well as illustrating them for the first time. The study included 39 Scarabaeus species, 17 Copris species, 7 Trox species, 4 Cetonia and 4 Trichius species. Familiar beetles such as Canthon viridis , Macrodactylus angustatus and Osmoderma scabra were first described by him. Many of

1600-1009: Was published in 1997 by Kenrick and Crane. In 2004, Crane et al. published some simplified cladograms , based on a number of figures in Kenrick and Crane (1997). Their cladogram for the lycophytes is reproduced below (with some branches collapsed into 'basal groups' to reduce the size of the diagram). Cooksonia  cambrensis, Renalia , Sartilmania , Uskiella , Yunia †  Hicklingia Adoketophyton , Discalis , Distichophytum (= Rebuchia ), Gumuia , Huia , Zosterophyllum  myretonianum , Z. llanoveranum, Z. fertile Zosterophyllum divaricatum , Tarella , Oricilla , Gosslingia , Hsua , Thrinkophyton , Protobarinophyton , Barinophyton  obscurum , B. citrulliforme , Sawdonia , Deheubarthia , Konioria , Anisophyton , Serrulacaulis , Crenaticaulis Nothia , Zosterophyllum  deciduum extant and extinct members In this view,

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