Basal Seed Plants †

Aglosperma †

• Hilton & Edwards, 1996

• Famennian of the UK

• Para-ovules

A. quadrapartita

• Hilton & Edwards, 1996

A. avonensis

• Hilton, 1998

Alasemenia tria †

• Wang et al., 2024

• Famennian of Anhui Province, China

• Dichotomous branches bearing terminal and acupulate ovules

• Three broad wing-like integumentary lobes radially and symmetrically attached to each nucellus, distally tapered and proximally reduced. 

• Integumentary lobes evidently extending outwards, with their free parts ca. 40% of ovule length. 

• Individual integumentary lobes fold inwards along the abaxial side. 

• Nucellus largely adnate to the integument.

Archaeosperma arnoldii †

• Famennian of Pennsylvania

• Pettitt & Beck, 1968

• Branching systems ("Moresnetia-type") bearing cupules with seeds

• Cupule had 5-6 broad lobes

Condrusia †

• Stockmans, 1948

• Famennian of Belgium & Russia

• Para-ovules are enclosed in a well-developed wing, composed of two flat cupule segments adpressed against each other

C. brevis

• • Petrosyan in Lepekhina et al., 1962

  • Famennian of Russia

C. minor

• • Stockmans, 1948

  • Famennian of Belgium

C. rumex

• • Stockmans, 1948

  • late Famennian of Belgium

Cosmosperma polyloba †

• Wang et al., 2014

• Famennian of South China (Wutong Formation, Changxing County)

• Cupulate ovules: one ovule surrounded by up to 16 distal segments and with minute spines on the outer surface

• Synangiate pollen organs bearing six to eight microsporangia fused only at the base,

• Planate and highly dissected pinnules in alternate arrangement

Elkinsia polymorpha †

• Rothwell et al., 1989; Serbet & Rothwell, 1992

• Late Devonian of West Virginia

• Elkinsia has an unbranched stem, with pinna-bearing fronds proximally on the plant

  • Stems are terete with three-ribbed centarch protostele, maturation of other protoxylem marginally mesarch.

  • Fronds helically arranged, composed of terete rachides with papillionoid, C-shaped bundles proximally and circular bundles distally, vegetative fronds with sphenopterid pinnules

• Distally, the plant displays "fertile cruciately forking fronds with terminal cupules or prepollen organs" (Serbet & Rothwell 1992)

  • There are four (pre)ovules born in each cupule (=cup-like branch system surrounding ovule)

  • These ovules are considered "preovules" (para-ovules) since the integument "...does not completely surround the nucellus to form a functional micropyle" (Serbet & Rothwell 1992)

  • There are 16 sterile branch tips surrounding preovules

Dorinnotheca streelii †

• Fairon-Demaret, 1996

• Famennian of Belgium

• 3-4 integument lobes around nucellus

• Cupule is large with 8 proximally-fused parts, forming a cup; distal ends are divided into at least 40 free tips

• Cupule may aid in wind dispersal

Guazia dongzhiensis †

• Wang et al., 2021

• Late Devonian (Famennian) of China

• This ovule is apparently without a cupule, unlike other Late Devonian seeds.

• Dichotomous fertile branches bearing terminal ovules

• Ovules elongate, obovoid, radially symmetrical and lacking a cupule

• Four broad wing-like lobes as integumentary outgrowths cruciately-arranged in each ovule, distally tapered, and proximally reduced

• Individual integumentary lobes folding inwards along abaxial side

• Free parts of integumentary lobes 30%-40% of ovule length

• Nucellus present except for near apex adnate to integument

• Nucellar apex dome-shaped. 

Glamorgania gayerii †

• Hilton, 2006

• Famennian of Wales

• "Moresnetia-type" seed

Hydrasperma tenuis †

• Matten et al., 1975

• Famennian

• The cupules containing 2–6 seeds are borne in pairs. 

• Each cupule is campanulate and composed of up to 24 oval to terete units. 

• The axis of the cupule is forked, each resultant branch dividing in an alternate monopodial fashion producing six major axes

Granditetrasporites zharkovae †

• Arkhangelskaya & Turnau, 2003

• mid-Givetian of Russia

• Dispersed tetrahedral tetrads composed of one large (presumably fertile) megaspore and three smaller (presumably aborted) ones adhering to its apical end. 

• The spore wall is two-layered, and the exine is detached from exoexine to a varying degree or closely appressed to it.

• Exine surface is minutely granular; that of the large megaspores bears an ornament of small and low elements. 

• Exine ultrastructure is not fibrous.

• This taxon may be a progymnosperm 

• It is also implied that the parent plants of the described seed-megaspores arose from ancestors that displayed only a low grade of heterospory.

Moresnetia zalesskyi †

• Stockmans, 1948; Fairon-Demaret & Scheckler, 1987

• Famennian of Belgium

• Branching systems bearing cupules with seeds

  • Cupule had 8-10 thin lobes

Runcaria heinzelinii †

• Stockmans, 1968; Gerrienne, 2004

• Givetian of Belgium

• A para-ovule that may represent an intermediate between the spore-bearing and seed-bearing habit.

• The indehiscent megasporangium bears a long distal columnar extension

• The integument is dissected (not incomplete), composed of multiple spirally disposed lobes. 

• The basal part of Runcaria is enclosed in a cup-like cupule composed of four segments.

Telangiopsis sp. †

• Wang et al., 2016

• Famennian of Wutong Formation, Dongzhi County, Anhui Province, China

• Pollen organ associated with, but not attached to, vegetative fronds

• Fertile axes with terminal pollen organs are dichotomous for 2-4 times, and may be proximally attached by fragmentary pinnules

• Pollen organs are synangiate and borne on the top of a short stalk

  • Synangia are radial in symmetry, and each consists of 4-8 elongate microsporangia fused at the base. 

  • Microsporangia have a longitudinal dehiscence line and show a tapered apex

• The associated stem is spiny and bears a vegetative frond that bifurcates once at the basal-most part. 

  • Frond rachises possess one order of pinna arranged alternately

  • Pinnules are borne alternately, planate, highly dissected, and equally dichotomous for 2-3 times. 

• Telangiopsis sp. reinforces that the Late Devonian pollen organs are synangiate usually with basally fused microsporangia.