Lagenophrys Stein, 1852

Mayén-Estrada, Rosaura & Clamp, John C., 2016, An annotated checklist of species in the family Lagenophryidae (Ciliophora, Oligohymenophorea, Peritrichia), With a brief review of their taxonomy, morphology, and biogeography, Zootaxa 4132 (4), pp. 451-492 : 455

· Lagenophrys Stein, 1852

is the largest genus, with 62 known species. The lorica is usually hemispheroidal ( Fig. 2–3 ) but is ovoid ( Fig. 4 ) in a few species as an adaptation for attaching to setae of the host1. The lorica aperture is an invaginated tube (loricastome) closed by drawing the outer edges (lips) together ( Fig. 2 B–C). Characteristics of the lorica aperture, especially the lips, are remarkably diverse among species of Lagenophrys ( Fig. 4 ). Details of the lorica aperture are species-specific and, usually, show relatively little intraspecific variation (Clamp 1990); however, the lips of the lorica aperture are highly variable in a few species (Clamp 1990, 1992). Other than their distinctive lorica aperture, members of Lagenophrys are unique in undergoing a special sequence of asexual divisions (second-type division) to abandon the exoskeleton of the host.

Figures

FIGURE 2. Characteristics of Lagenophrys. A. L. aselli on surface of pleopod of freshwater isopod. B. Lagenophrys ampulla, a typical representative of the genus, dorsal view. C. Lagenophrys labiata, lateral view. A, from Clamp 1988 b; B – C, from Clamp 1991. Abbreviations: Ap, ampulla of cytostome (the cytopharynx leading into the cytoplasm is distended with a food vacuole); AL, anterior lip of lorica aperture; C, peristomial cilia (shown in outline); CT, crescentic thickening in wall of lorica anterior to lorica aperture; Cy, cytoplasm; EC, external collar of lorica aperture; ED, epistomial disk; If, infundibulum; Lo, dorsal wall of lorica; LR, rim of lorica; Ls, loricastome; LX, longitudinal axis of organism; MaN, macronucleus; MiN, micronucleus; PL, posterior lip of lorica aperture; PM, myoneme in edge of peristomial lip; TX, transverse axis of organism.

FIGURE 3. Dorsal views of six species of Lagenophrys illustrating interspecific diversity in characteristics of the lorica, especially the aperture, and the shape and position of the macronucleus. A. L. crutchfieldi. B. L. callinectes. C. L. novazealandae. D. L. matthesi. E. L. branchiarum. F. L. nassa. A, from Clamp, 1993; B, from Clamp, 1989; C, from Clamp, 1994; D – F, from Clamp, 1984. Abbreviation: Dv, plane of division. All scale bars = 10 µm.

FIGURE 4. Diversity of Lagenophrys spp. Intraspecific variation and adaptation for attachment to setae. A, B. Two morphs in a population of L. machaerigera that represent the extreme range of variation in outgrowth of the anterior lip of the lorica aperture and thickening of the posterior lip. C. Dorsal view of L. lenticula, which attaches to setae of the amphipod Hyalella with a posterior prolongation of the lorica (Ps, pseudostalk). D. Dorsal view of L. vaginicola, which attaches to caudal setae of harpacticoid copepods. A, from Clamp 1992; B – D, from Clamp 1991. All scale bars = 10 µm.