scholarly journals Spatial analysis of morphological variation in African honeybees (Apis mellifera L.) on a continental scale

Apidologie ◽  
2000 ◽  
Vol 31 (2) ◽  
pp. 191-204 ◽  
Author(s):  
Jos� A.F. Diniz-Filho ◽  
H. Randall Hepburn ◽  
Sarah Radloff ◽  
Stefan Fuchs
2019 ◽  
Vol 50 (12) ◽  
Author(s):  
Rosa Daniela Tovilla‐Sierra ◽  
Leonel Herrera‐Alsina ◽  
Rafael Bribiesca ◽  
Héctor T. Arita

2009 ◽  
Vol 4 (1) ◽  
pp. 129 ◽  
Author(s):  
Renato L. Jr. Sandes ◽  
Cláudia L. Oliveira ◽  
Edvana S. Ferreira ◽  
Emersom Cruiff ◽  
Cezar Tavares ◽  
...  

2021 ◽  
Author(s):  
Robert Bischoff ◽  
James Allison

The Fremont projectile point typology was developed in the 1980s. An early revision combined the Rose Spring Corner-notched and Eastgate Expanding-stem types into a combined Rosegate type with an end date of 900-1000 AD. Some archaeologists recognize that these projectile points persist to approximately 1300 AD but others use the earlier dates. Furthermore, there is a varied approach to these types. Some use the original two types, while others use Rosegate or a combination of Rosegate, Rose Spring, and Eastgate. We used projectile point typology data, illustrations, and photographs to study the temporal range and morphological variation of Rosegate points. We found that Rosegate points are common throughout the Fremont period, with some decline over time. A spatial analysis demonstrates that the points are found throughout the Fremont region but are not evenly distributed. Our morphological analysis does not support the separation of Rosegate points into two distinct types.


Author(s):  
Maria Anna Pabst

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).


1982 ◽  
Vol 93 (1-2) ◽  
pp. 71-76
Author(s):  
S. Kokkini ◽  
D. Babalonas

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