Patricia M. Bonamo

Early land animals in north america: evidence from devonian age arthropods from gilboa, new york.

A new fossil site near Gilboa, New York, is one of only three where fossils of terrestrial arthropods of Devonian age have been found. The new Gilboan fauna is younger than the other two but richer in taxa. Fragmentary remains and nearly whole specimens assigned to Eurypterida, Arachnida (Trigonotarbida, Araneae, Amblypygi, and Acari), Chilopoda [Craterostigmatomorpha(?) and Scuterigeromorpha(?)], and tentatively to Insecta (Archaeognatha) have been found. The centipedes and possible insects may represent the earliest records known for these groups.

Leclercqia complexa gen. et sp. nov., a new Lycopod from the late middle devonian of eastern New York

Abstract Leclercqia complexa gen. et. sp. nov. is described as a slender, herbaceous lycopod assigned to the family Protolepidodendraceae. Its laminar leaves are divided into an elongate, acuminate, often recurved central division and two opposite, divided, lateral divisions. Leaves are in a low spiral, eight to ten per gyre. Each has a single vein composed of tracheids. Lateral branches from this vein extend only to the base of each lateral division. The main vein extends to tip of leaf. Stomata are slightly sunken and scattered. The xylem strand is a solid rod with fourteen to eighteen protoxylem ridges; maturation is exarch. Protoxylem is composed of annular, spiral, and reticulate elements. Metaxylem is composed of scalariform elements and tracheids with elongate to oval and uni- to multiseriate bordered pits. Leaf traces rise from protoxylem ridges and extend obliquely to bases of leaves. Sporangia are globose to elliptical, attached to sporophylls by a pad of tissue just proximal to the lateral segments and have sporangia on their walls. Dehiscence occurs along the upper margin of the sporangium and is parallel to midline of sporophyll. Groups of sporophylls alternate with vegetative leaves. Spores in situ 60–85 μ in diameter exclusive of ornamentation, with curvaturae perfectae, spinae 5–9 μ long on an equatorial ridge, and biform ornamentation on distal and proximal faces. Plant is eligulate and probably homosporous.

A Devonian Spinneret: Early Evidence of Spiders and Silk Use

A nearly complete spider spinneret was found in Middle Devonian rocks (about 385 to 380 million years old) near Gilboa, New York. This is the earliest evidence yet discovered for silk production from opisthosomal spigots, and therefore for spiders. Two previously known Devonian fossils described as spiders lack any apomorphies of the order Araneae and are probably not spiders. The spigots of the Devonian spinneret resemble those of members of the living suborder Mesothelae, but the number of spigots and their distribution are like those of members of the suborder Opisthothelae, infraorder Mygalomorphae. The Devonian spider belonged to a clade that may be the sister group of all other spiders, of Mesothelae, or of Opisthothelae.

A Terrestrial Alicorhagiid Mite (Acari: Acariformes) from the Devonian of New York

Archaeacarus dubinini n. gen., n. sp., is described and illustrated based on a specimen recovered from the terrestrial fossiliferous mudstone deposits of Devonian age at Gilboa, New York. Observable character-states are consistent with its inclusion in the extant family Alicorhagiidae, one of the early-derivative taxa of the mite order Acariformes. This family record is consistent with the presence of related extant mite families in the Devonian-age Rhynie Chert of Scotland, and lends support to the validity of the latter material.

The Wood of Rellimia from the Middle Devonian of New York

Rellimia is one of the best known of the progymnosperms, although the anatomy of its wood and tree structure has yet to be fully described. The occurrence of Rellimia in Devonian strata makes it one of the earliest plants known to have developed wood. This study examines pyrite permineralizations from the Catskill region of New York and elucidates anatomical details of the secondary xylem using light and scanning electron microscopy. The wood is pycnoxylic with tall, narrow rays that are typically uniseriate, although biseriate and multiseriate rays can be present. Ray cells are slightly rectangular, and the rays are homocellular. All cells appear to have thin walls and appear to be ray parenchyma. Tracheids have crowded, circular‐bordered pits on all walls, including the long, tapering end walls. Bordered pits are in alternate spirals across the face walls and are often hexagonal in outline. Fractures through the bordered pit pair reveal details of the wall and pyrite casts that fill the pit canal and pit chamber during fossilization. Bordered pit pairs have crossed pit apertures, with the pit canal being longer than the shallow pit chamber. Preserved pit membranes and secondary walls show microfibrillar arrangement. Anatomical characteristics of the known wood of progymnosperm taxa are compared and discussed in light of the group’s position in lignophyte evolution.

The Primary Body of Rellimia thomsonii: Integrated Perspective Based on Organically Connected Specimens

The Blenheim‐Gilboa locality in New York contains Rellimia thomsonii specimens preserved as both compressions and permineralizations that offer an unusually complete perspective on the reproductive structures, primary body, and secondary anatomy of this Middle Devonian plant. Here we describe the vegetative appendages, axis and branch size relationships, and trace departure as well as primary anatomy, including phloem sieve cells of interconnected axis orders of vegetative and fertile specimens. At least five orders are present, and each axis order is approximately half the diameter of the parent axis. Three‐ribbed protosteles are evident in all axes. Protoxylem in transverse section is a continuous three‐ribbed sheet one or two tracheids wide, enveloped by several cell layers of metaxylem in turn surrounded by primary phloem. Sieve cells have vertically arranged sieve areas. Trace departure to axes is similar in vegetative and fertile axes. Traces are apparent proximally as radial elongations of the tip of the parent primary xylem rib. In distal sections, the rib tip is tangentially elongated; ultimately, the trace becomes three‐ribbed. Traces to vegetative appendages and fertile organs divide dichotomously. The new features described here allow us to expand and complement previous work and to discuss our whole‐plant concept of Rellimia.