Abstract
In this study, the hemolymph vascular system (HVS) in two cambarid crayfishes, i.e. the Marbled Crayfish, Procambarus virginalis Lyko, 2017 and the Spiny Cheek Crayfish, Faxonius limosus (Rafinesque, 1817), is investigated in regard of areas of non-genetic phenotypic variation. Despite their genetic identity, specimens of P. virginalis show variability in certain features of the HVS. Thus, we describe varying branching patterns, sporadic anastomoses, and different symmetry states in the vascular system of the marbled crayfish. We visualize our findings by application of classical and modern morphological methods, e.g. injection of casting resin, micro-computed tomography and scanning electron microscopy. By comparing our findings for P. virginalis to the vasculature in sexually reproducing crayfishes, i.e. F. limosus and Astacus astacus, we discuss phenotypic variation of the HVS in arthropods in general. We conclude that constant features of the HVS are hereditary, whereas varying states identified by study of the clonal P. virginalis must be caused by non-genetic factors and, that congruent variations in sexually reproducing F. limosus and A. astacus are likely also non-genetic phenotypic variations. Both common causal factors for non-genetic phenotypic variation, i.e., phenotypic plasticity and stochastic developmental variation are discussed along our findings regarding the vascular systems. Further aspects, such as the significance of non-genetic phenotypic variation for phylogenetic interpretations are discussed.
Highlights
Intraspecific variability of arthropod circulatory systemsThe circulatory systems of arthropods have been shown to be subject to a high degree of intraspecific variability
We describe different kinds of intraspecific variability of vascular morphology exemplified by visualizations of alternative vascular morphologies in several individuals of P. virginalis
In the vascular morphology of P. virginalis and F. limosus, we found several areas showing intraspecific variability of three different kinds: (1) variability in branching patterns of arterial systems, (2) variable occurrence of anastomoses, and (3) variable asymmetries (Fig. 2)
Summary
The circulatory systems of arthropods have been shown to be subject to a high degree of intraspecific variability. Such intraspecific variability can be found all across the arthropod tree of life and within all constituents of the hemolymph circulatory system. In Xiphosura, various prominent regions of both, the vascular system and the lacunar system have been shown to vary intraspecifically, as well as even the number of ostia (Göpel and Wirkner 2015). Institut für Biowissenschaften, Universität Rostock, Allgemeine und Spezielle Zoologie, Universitätsplatz 2, 18055 Rostock, Germany While the question of whether such intraspecific variability is genetically determined could not be answered in other species, the parthenogenetic marbled crayfish showed the same variability in its genetically identical offspring
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
