Leszek A. Błędzki

Population growth and production of Habrotrocha rosa Donner (Rotifera: Bdelloidea) and its contribution to the nutrient supply of its host, the northern pitcher plant, Sarracenia purpurea L. (Sarraceniaceae)

The population growth and biomass production of the pitcher-plant (Sarracenia purpurea L.) inquiline, Habrotocha rosa Donner (Rotifera: Bdelloidea), its consumption by other pitcher-plant inqulines, and its excretion of phosphorus (PO4–P) and nitrogen (NO3–N and NH4–N), were investigated in laboratory experiments. Observed population growth and production rate of H. rosa were higher at pH 4 (2.3 rotifers d-1) than at pH 3 (1.3 rotifers d-1), 5 (1.9 rotifers d-1), or 6 (0.8 rotifers d-1). Populations of H. rosa are an abundant and reliable food source for larvae of the dipteran inqulines Wyeomyia smithii (Coq.) and Blaesoxipha fletcheri (Aldrich) that co-occur with H. rosa in S. purpurea pitchers. Abundance of H. rosa within a pitcher is negatively associated with abundance of dipteran larvae, and these larvae consume rotifers in direct proportion to rotifer density (Type I functional response). Habrotrocha rosa may also account for the majority of the plants supply of N and P. An average population of rotifers in the field (∼400 per pitcher) can excrete ∼5.2 μg NO3-N, ∼3.91 μg NH4-N, and ∼18.4 μg PO4–P per day into a single leaf, and excretion rate is independent of water pH. Over the six-month growing season of pitcher-plants in Massachusetts, U.S.A., we estimate that rotifers could supply 8.8–43 mg of N and 18.2–88 mg of P. These values far exceed the amount of N and P previously estimated to be supplied annually to the plants through insect capture or rainfall.

Diversity of rotifers from northeastern U.S.A. bogs with new species records for North America and New England

The first geographically extensive survey of rotifers in New England (U.S.A.) bogs is presented. Rotifers were collected during the summers of 1999 and 2000 from 31 bogs occurring throughout Vermont and Massachusetts, and in northwestern Connecticut. The survey incorporates three microhabitats within bogs: the bog ponds, interstitial (pore) water, and water-filled leaves of the northern pitcher-plant, Sarracenia purpurea L. Species similarity of these three habitats was low (Jaccard indices of similarity <0.25). During the survey over 50 000 individuals in 38 species were collected including Cephalodella anebodica Berzins and Colurella obtusa clausa (Hauer) which are reported for the first time from North America. Fifteen new species records for New England, 5 for Connecticut, 26 for Massachusetts and 20 for Vermont are also reported. Species richness of rotifers increased significantly with bog elevation but not with latitude, longitude, or bog area. The current known North American distribution of the rotifers we found in these bogs is presented for comparison.

Introduction to Copepoda

The global diversity of free-living (non-parasitic) copepods is estimated to be around 2814 freshwater species out of around 11,500 morphospecies mostly found in marine environments (Humes 1994; Balian et al. 2008). These authors estimated the presence of 1204 species in the Palearctic area. The European part consists of around 25 % of the Palearctic area and the 158 copepod species described here in our key make up slightly less than 15 % of the total number of species estimated for the Palearctic, including both surface and subsurface species.

The late Holocene appearance of European Bosmina (Eubosmina) thersites (Crustacea, Cladocera) in lakes surrounding the Baltic Sea

This study shows the appearance of Bosmina (Eubosmina) thersites during the last millennium in two lakes in Northern Europe: Lake Charzykowskie (Poland) and Lake Lohja (Estonia). Cladocera remains collected from both lakes showed similar Bosmina species composition and changes during the late Holocene. Older sediment layers showed a prevalence of smaller Eubosmina species (B. (E.) longispina), indicating oligotrophic conditions of the lakes, while younger layers were dominated by larger species (B. (E.) coregoni and B. (E.) thersites), typically found in lakes with higher trophy. The presence of B. (E.) thersites has rarely been reported in paleolimnological research, and this is the first observance of its high abundance in lake sediments. More research is needed, however, to better understand the appearance, speciation driver, continental range, and ecological preferences of B. (E.) thersites.

Negotiating Peer Mentoring Roles in Undergraduate Research Lab Settings

Undergraduate research is viewed as an important catalyst for educational engagement and persistence, with an emphasis on the faculty mentoring relationship. Despite the common practice of having multi-tiered lab teams composed of newer undergraduates and more seasoned undergraduates serving as peer mentors, less is understood about the experience of peer mentors. Using the framework of legitimate peripheral participation, this study examined how peer mentors negotiated their roles in the lab. Nested case studies based on interviews with peer mentors, faculty members, and newer students illustrated how peer mentors establish credibility through prior lab experience and faculty-framed authority. Delegating supervision was an important component that helped newer students to accept the authority of the peer mentor. Implications for program development and future research involving peer mentoring are discussed.

Ecological Features, Coefficients, and Equations

Various ecological projects have required basic ecological features, coefficients, or equations describing Cladocera and Copepoda; some of them are presented in Table 2.1.

Characteristics of Orders, Families, and Genera with a List of European Species

This section covers description of Cladocera taxonomic ranks and provides a list of genera and species reported from Europe.

Key to Copepoda

This chapter covers the dichotomous-pictorial key for genera and species identification of planktonic Copepoda (Calanoida, Cyclopoida) reported from Europe. Here, we provide separate male and female keys to the calanoid copepods, for both, the genera and species levels. We attempted to use autapomorphic characters and, whenever possible, almost a single character to distinguish between similar species, in an easy pictorial way, avoiding long verbal descriptions equipped with scientific jargon. Keys to families, genera and species are arranged into plates with an easy-to-use pictorial guide.

Key to Cladocera

This chapter covers the dichotomous-pictorial key for genera and species identification of planktonic Cladocera reported from Europe. We attempted to use autapomorphic characters and, whenever possible, almost a single character to distinguish between similar species, in an easy pictorial way, avoiding long verbal descriptions equipped with scientific jargon. Keys to families, genera and species are arranged into plates with an easy-to-use pictorial guide.

Characteristics of Orders and Families with a List of European Genera and Species

The order Calanoida is composed of species with 16–26-segmented antennules and biramous antennae. The leg P5 is modified into a copulatory organ in males. The abdomen is narrow and a heart is present. The order is composed of 42 families with 289 genera of which only four families are present exclusively in freshwaters and another five are freshwater and marine. Only four families and 22 genera are reported from European freshwaters (Dussart and Defaye 2001, 2002; Boxshall and Halsey 2004). The order Calanoida is a rather homogeneous group, adapted primarily to planktonic life (Park 1986). Andronov (1974) divided the order of Calanoida into nine superfamilies (based on the structure of the male A1 and legs P1–P6 in both sexes) and later Park (1986) divided them into 11 superfamilies, which was generally recognized by Boxshall and Halsey (2004). The first parsimony-based phylogeny using morphological data for the calanoid copepods was provided by Bradford-Grieve et al. (2010). Soon after, Blanco-Bercial et al. (2011) elaborated the molecular-based phylogenetic analysis. Both analyses (morphological and molecular) recover several monophyletic lineages within the Calanoida that largely conform to the superfamilies recognized in intuitive classification by Andronov (1974), Park (1986), and Boxshall and Halsey (2004).