Kristina M. Hill-Spanik

• MS, College of William & Mary
• Laboratory Manager at College of Charleston

The genus Bonamia (Haplosporidia) includes economically significant oyster parasites. Described species were thought to have fairly circumscribed host and geographic ranges: B. ostreae infecting Ostrea edulis in Europe and North America, B. exitiosa infecting O. chilensis in New Zealand, and B. roughleyi infecting Saccostrea glomerata in Australia....

The significance of infectious disease has intensified as our marine ecosystems are increasingly altered, with molluscan taxa being among the affected. One of the important pathogens to emerge in recent years, the oyster parasite Bonamia exitiosa, has a broad geographic distribution and has been found to infect a number of oyster species. In order...

The coquina, Donax variabilis , is a known intermediate host of monorchiid and gymnophallid digeneans. Limited morphological criteria for the host and the digeneans’ larval stages have caused confusion in records. Herein, identities of coquinas from the United States (US) Atlantic coast were verified molecularly. We demonstrate that the current Gen...

A new genus and species within the family Polymorphidae Meyer, 1931 were erected to accommodate cystacanths recovered from the mesentery of individuals from a non-native population of the red swamp crayfish Procambarus clarkii (Girard), collected from South Carolina (USA). Morphological characteristics of the specimens collected included in both se...

Bacteria drive energy fluxes and geochemical processes in estuarine sediments. Deposit-feeding invertebrates alter the structure and activity of microbial communities through sediment ingestion, gut passage, and defecation. The eastern mud snail, Ilyanassa obsoleta, is native to estuaries of the northwestern Atlantic, ranging from Nova Scotia, Cana...

A BioBlitz is a rapid and intensive survey of a specific geographic area that brings together experts and often lay participants to assess biodiversity, typically of macrobiota that are easily observed and identifiable on-site. This concept has become popular across taxonomic fields, attracting interest globally to increase knowledge of local biodi...

Bonamia (Haplosporida) are oyster parasites capable of devastating oyster populations. The near-circumglobal distribution of the host generalist B. exitiosa has previously been associated with the natural and anthropogenic dispersal of broadly distributed non-commercial oysters in the Ostrea stentina species complex. Here, we took a global snapshot...

Aim Parasites in the genus Perkinsus infect marine molluscs globally, with novel detections expanding and reshaping our knowledge of their biogeographic patterns and the factors influencing those patterns. Here, we aimed to characterize the phylogeography and genetic connectivity of Perkinsus spp. in bivalves across North and Central America, which...

The Papahānaumokuākea Marine National Monument, Hawai‘i, is one of the most isolated and protected archipelagos in the world, making it a natural laboratory to examine macroalgal-microbial diversity because of limited direct anthropogenic impacts. We collected the most abundant macroalgae from nine sites ranging from shallow subtidal (1.5 m) to mes...

Three juvenile Atlantic tripletail Lobotes surinamensis caught opportunistically in Charleston Harbor (South Carolina, USA) and maintained in captivity for over three months displayed an altered swimming behavior. While no direct causation can be demonstrated herein, fish were infected in their brain by strigeid trematode larvae (metacercariae) of...

Cryptic species of coquina clams Donax fossor and D. variabilis carry the hydroid epibiont Lovenella gracilis and are infected with metacercariae of the monorchiid parasites Lasiotocus trachinoti and L. choanura . The associations among this host–epibiont–parasite system were investigated. Fifty clams were collected at low tide over 3 days in June...

Microphytobenthos (MPB), typically comprised mainly of diatoms, is a key contributor to nearshore energy flow and nutrient cycles. Deposit-feeding invertebrates are known to alter the structure and activity of MPB. The eastern mud snail Ilyanassa obsoleta can reach extremely high densities in estuaries of the northwestern Atlantic, and their deposi...

Sebkha Imlili (Atlantic Sahara) is a salt flat with over 160 permanent holes of hypersaline water generated in the Holocene and inhabited by euryhaline organisms that are considered to be relics of the past, including the cichlid fish Coptodon guineensis . We surveyed the fish parasites four times over one year, to i) identify the parasites, and ii...

Understanding the combined effects of multi-parasite infections on their hosts is necessary for documenting parasite impacts and is particularly important for developing effective management strategies for economically important organisms. The white shrimp Penaeus setiferus supports important recreational and commercial fisheries along the southeas...

Neonates of hammerhead sharks (Sphyrnidae), Sphyrna lewini (Griffith and Smith, 1834), the sympatric cryptic species, Sphyrna gilberti Quattro et al., 2013, and their hybrids were captured in the western North Atlantic, along the coast of South Carolina, USA, between 2018 and 2019 and examined for gill monogenoids. Parasites were identified and red...

Marine microbes provide the backbone for pelagic ecosystems by cycling and fixing nutrients and establishing the base of food webs. Microbial communities are often assumed to be highly connected and genetically mixed, with localized environmental filters driving minor changes in structure. Our study applied high-throughput Illumina 16S ribosomal RN...

Generally, most eukaryotic organisms form relationships with microbes that are important in mediating host organismal health. Macroalgae are a diverse group of photosynthetic eukaryotic organisms that serve as primary producers and foundational species in many ecosystems.

For many taxa, including isomorphic haplodiplontic macroalgae, determining sex and ploidy is challenging, thereby limiting the scope of some population demographic and genetic studies. Here, we used double digest restriction site‐associated DNA sequencing (ddRAD‐seq) to identify sex‐linked molecular markers in the widespread red alga Agarophyton ve...

For endangered sea turtle populations, microbial pathogens of developing embryos are of concern at nesting sites around the globe. For olive ridley turtles, hatching success is markedly lower at mass-nesting sites than at solitary nesting beaches, a case presumably resulting from the abundance of decomposing eggs generated by nesting turtles destro...

Benthic microalgae play important roles in energy flow and biogeochemistry of coastal ecosystems; however, factors influencing community composition remain largely unknown. Our purpose was to identify and compare spatial and environmental influences on benthic diatom biogeography at regional scales. In summer 2018, we sampled sediment at various sp...

The sciaenid Spotted Seatrout (Cynoscion nebulosus) are infected by blood flukes (Cardicola spp.). A 2 year survey in estuaries of South Carolina, USA, showed that adult flukes and granulomas occurred throughout the year but their prevalence was highest in summer (61% and 84%, respectively), indicating an unusually high level of infection for wild...

Benthic microalgae are of great significance to coastal productivity and nutrient cycling, yet determinants of their biogeography and community assembly remain unclear. We identified and compared spatial and environmental mechanisms that shape beach diatom biogeography and diversity at regional scales. We sampled at various spatial scales (from 10...

One method of preserving beaches against the effects of erosion and sea level rise is beach renourishment. While there have been many studies assessing the impact of renourishment on macrofauna, few studies have looked at its effects on microbes. Benthic microalgae (BMA) are important primary producers, representing the basis of nearshore food webs...

Kudoa inornata is a myxosporean parasite that develops in the somatic muscle of spotted seatrout Cynoscion nebulosus, an economically and ecologically important fish in estuaries and harbors in southeastern North America. In South Carolina (SC), USA, over 90% of wild adult spotted seatrout are infected. To inform potential mitigation strategies, we...

Panama is a major hub for commercial shipping between two oceans, making it an ideal location to examine parasite biogeography, potential invasions, and the spread of infectious agents. Our goals were to (i) characterize the diversity and genetic connectivity of Perkinsus spp. haplotypes across the Panamanian Isthmus and (ii) combine these data wit...

Molecular-based community profiles often overestimate species richness and diversity as they are incapable of distinguishing DNA signals derived from extracellular or moribund sources from that of viable organisms. Propidium monoazide (PMA), a double stranded DNA-binding dye, was used to selectively isolate the genetic signature of viable diatoms f...

Benthic microalgae are key contributors to near-shore food webs and sediment stabilization. Temporal variability in microalgal biomass and production throughout the tidal cycle has been well documented; however, due to limitations of traditional methods of analysis patterns of community composition and diversity over such time scales have not been...

The Alpheus armillatus H. Milne Edwards, 1837 species complex contains several cryptic species of snapping shrimps including Alpheus angulosusMcClure, 2002. A previous study of the phylogeography and coloration of the A. armillatus species complex found three distinct lineages of A. angulosus distributed throughout the Gulf of Mexico, Caribbean, an...

The invasive nematode Anguillicoloides crassus parasitizes the swim bladder of eels, including that of the American eel, Anguilla rostrata. Despite its potential devastating effects on eel populations, however, its intermediate host(s) is/are unknown in North America. The goal of this study was to determine whether An. crassus could infect copepods...

S U M M A R Y Parasites can exert strong effects on population to ecosystem level processes, but data on parasites are limited for many global regions, especially tropical marine systems. Characterizing parasite diversity and distributions are the first steps towards understanding the potential impacts of parasites. The Panama Canal serves as an in...

Taxonomic uncertainty often limits our ability to resolve biogeographic patterns and discern biological invasions. Within the bivalve mollusks, this uncertainty is particularly acute for oysters, as the high degree of phenotypic plasticity of their shells creates taxonomic confusion. The integration of molecular data with shell morphology can diffe...

Previously reported in Australia, New Zealand, and more recently in Europe, the protistan parasite Bonamia exitiosa was also reported in the mid-Atlantic region of the USA after causing serious mortalities there in the Asian oyster Crassostrea ariakensis. At the time, this oyster was being considered for introduction, and the potential consequences...

Protistan oyster parasites in the genus Bonamia have been observed in recent years infecting new hosts on five continents, with most of these parasites genetically similar to austral species Bonamia exitiosa and Bonamia roughleyi. Identification of the newly observed parasites as one or another of these described species has been complicated by the...

To assess potential benefits and liabilities from a proposed introduction of Asian Suminoe oysters, susceptibilities of exotic Crassostrea ariakensis and native C. virginica oysters were compared during exposures to pathogens endemic in temperate, mesohaline waters of Chesapeake Bay and sub-tropical, polyhaline Atlantic waters of southern Florida,...

The small non-commercial oyster Ostrea stentina co-occurs with commercially important Ostrea edulis in the Mediterranean Sea, yet its disposition with respect to the destructive pathogens Bonamia ostreae and Marteilia refringens is unknown. We began an evaluation of the Bonamia spp. infection status of O. stentina from Hammamet, Tunisia, in June 20...

UNDERSTANDING BONAMIA PARASITES BY EXPLORING THEIR PHYLOGENY, THEIR HOSTS, AND THEIR PAST