Benthic marine diatom flora of Guam: new records, redescription of Psammodictyon pustulatum n. comb., n. stat., and three new species (Colliculoamphora gabgabensis, Lauderia excentrica, and Rhoiconeis pagoensis) Author Lobban, Christopher S. Division of Natural Sciences, University of Guam, Mangilao, GU 83823, USA e-mail: clobban @ guam. net clobban@guam.net text Micronesica 2015 2015 2 1 49 journal article 299054 10.5281/zenodo.12117576 9ec266f5-1dc7-4272-9fbc-67c7f2b0f5aa 0026-279X 12117576

Table 1. Comparison of Rhoiconeis species.

Character	R. bolleana (Grunow) Medlin	R. sponsalia (Giffen) Medlin	R. pagoensis n. sp.
a Numbers in brackets from Cleve (1895), others from Medlin (1985).
Length (µm)	40–60 [45–95]a	20–42	16–49
Width (µm)	9–10 [10–11]a	5–7.5	6.7–7.9 (only 2 samples)
Striae in 10 µm	8–11 at center, denser at apices	13–15, consistent throughout	16–22
Stria angle	Radiate throughout, more strongly towards apices	Radiate throughout	Radiate throughout
Central area	On concave valve quadrate, 3–5 shorter striae; on convex elliptical, 1–3 short striae	On concave valve quadrate, 3–4 shorter striae; on convex elliptical, fewer short striae	Both valves 2–5 short striae, both can have quadrate central area, narrow area seen only on convex valve.
Plastids	unknown	unknown	Two plates, lying along girdle faces
Girdle bands	unknown	valvocopula and pleura in 2 parts	valvocopula and pleura in 2 parts