The Role of Alternate Hosts in the Ecology and Life History of Hematodinium sp., a Parasitic Dinoflagellate of the Blue Crab (Callinectes sapidus)

• Published in: The Journal of parasitology Vol. 98; no. 1; pp. 73 - 84
• Main Authors: Pagenkopp Lohan, Katrina M, Reece, Kimberly S, Miller, Terrence L, Wheeler, Kersten N, Small, Hamish J, Shields, Jeffrey D
• Format: Journal Article
• Language: English
• Published: 810 East 10th Street, Lawrence, Kansas 66044 American Society of Parasitologists 01-02-2012; Allen Press Inc
• Subjects: Alveolata - genetics; Alveolata - growth & development; Alveolata - physiology; Amphipoda; Animals; Bays; Biological and medical sciences; Biological taxonomies; Brachyura - parasitology; Callinectes sapidus; Cloning, Molecular; Crabs; Crustacea - classification; Crustacea - parasitology; Crustaceans; Decapoda; DNA, Protozoan - chemistry; DNA, Protozoan - isolation & purification; Estuaries; Fisheries; Fundamental and applied biological sciences. Psychology; General aspects; General aspects and techniques. Study of several systematic groups. Models; Hematodinium; Histology; Histopathology; Host Specificity; Host-Parasite Interactions; Infections; INVERTEBRATE-PARASITE RELATIONSHIPS; Invertebrates; Life Cycle Stages - physiology; Life history; Marine; Microorganisms; Mud; Parasite hosts; Parasites; Parasitic diseases; Polymerase Chain Reaction; Protozoa; Sequence Alignment; Sequence Analysis, DNA; Shellfish; Virginia; Virginia; United Kingdom > UK; United States > US; Chesapeake Bay; Georgia; Florida; Maryland; Delmarva Peninsula; AW, Atlantic; ANW, USA, Virginia; ANW, USA, Delaware, Delmarva Peninsula; Crustacea; Dinozoa; Protozoa; Callinectes sapidus; Life history; Arthropoda; Brachyura; Parasite; Ecology; Host; Decapoda; Invertebrata
• ISSN: 0022-3395; 1937-2345
• DOI: 10.1645/GE-2854.1

Hematodinium sp. infections are relatively common in some American blue crab (Callinectes sapidus) populations in estuaries of the western Atlantic Ocean. Outbreaks of disease caused by Hematodinium sp. can be extensive and can cause substantial mortalities in blue crab populations in high salinities. We examined several species of crustaceans to determine if the same species of Hematodinium that infects C. sapidus is found in other crustaceans from the same localities. Over a 2-yr period, 1,829 crustaceans were collected from the Delmarva Peninsula, Virginia, examined for the presence of infections. A portion of the first internal transcribed spacer (ITS1) region of the ribosomal RNA (rRNA) gene complex from Hematodinium sp. was amplified and sequences were compared among 35 individual crustaceans putatively infected with the parasite, as determined by microscopic examination, and 4 crustaceans putatively infected based only on PCR analysis. Of the 18 crustacean species examined, 5 were infected with Hematodinium sp. after microscopic examination and PCR analysis, including 3 new host records, and an additional species was positive only via PCR analysis. The ITS1 rRNA sequences of Hematodinium sp. from the infected crustaceans were highly similar to each other and to that reported from C. sapidus (>98%). The similarity among these ITS1 sequences and similarities in the histopathology of infected hosts is evidence that the same species of Hematodinium found in C. sapidus infects a broad range of crustaceans along the Delmarva Peninsula. Our data indicate that the species of Hematodinium found in blue crabs from estuaries along the east coast of North America is a host generalist, capable of infecting hosts in different families within the Order Decapoda. Additionally, evidence indicates that it may be capable of infecting crustaceans within the Order Amphipoda.