Home Central American Mosses
Home
Name Search
Family List
Generic List
Species List
Daltoniaceae Schimp. Search in NYBG Virtual Herbarium Decrease font Increase font Restore font
 

Published In: Synopsis Muscorum Europaeorum 478. 1860. (Syn. Musc. Eur.) Name publication detail
 

Project Name Data (Last Modified On 2/5/2014)
Acceptance : Accepted
Project data     (Last Modified On 2/5/2014)
Discussion:

There has been considerable controversy over the composition of the Daltoniaceae, due mostly to the presence of a large number of generic pairs that have very similar gametophytes but radically different sporophytes. Crosby (1974b) restricted the family to those genera having a daltoniaceous peristome: exostome teeth papillose, with ventral plates narrower than the dorsal plates and median furrow absent; endostome papillose, with low basal membranes and cilia absent. Buck (1987, 1988), taking the opposite approach, stressed gametophytic similarities and placed in the Daltoniaceae only members of the Hookeriales that lacked pseudoparaphyllia and that had leaf costae typically single, leaves usually bordered, and calyptrae mitrate and fringed at the base.

Whittemore and Allen (1989) also re-evaluated the Daltoniaceae/Hookeriaceae problem from a gametophytic perspective. They noted that the different peristome morphologies within the Hookeri-ales were correlated with important functional differences: hookeriaceous peristome xerocastique, i.e., reflexed when dry and incurved when wet; daltoniaceous peristome hygrocastique, i.e., incurved when dry and outcurved when wet. Furthermore, they observed that the various daltoniaceous peri-stomes were not uniform in morphology and that similar morphologies occurred in other pleurocar-pous mosses. Finally, because of the lack of correlation in the Hookeriales between characters of the peristome and other organs, they concluded the daltoniaceous peristome had arisen more than once in the order. They defined the Daltoniaceae as a group of mosses with usually unicostate leaves, rhi-zoids branched (sometimes densely) and scattered over the cortex, axillary hairs (2–)3–10 cells long, plants usually unbranched, stem cortex deeply red pigmented, and mitrate, fringed calyptrae. Buck et al. (2005) examined the Hookeriales using molecular and morphological techniques. Although the list of genera they placed in the Daltoniaceae included some not considered by Whittemore and Allen (1989), the composition of the Daltoniaceae in both studies was essentially the same.


 

Export To PDF Export To Word

Plants simple or sparingly branched, erect, prostrate, or pendent. Stems usually dark red; central strand absent or occasionally present; axillary hairs (2–)3–12 cells long, hyaline or with only the basal cells pigmented (sometimes several cells pigmented in Bryobrothera); paraphyllia absent; pseudopa-raphyllia absent (filamentous to subfoliose in Adelothecium); rhizoids 1–3-pinnately branched, in clusters abaxial to the leaf insertions, scattered over the stem, or around branch buds. Leaves mono-morphic or dimorphic with lateral leaves larger than the ventral and dorsal leaves; margins often with a border of narrow, elongate cells; costae present, single or double, variable in length (costa some-times absent in Distichophyllidium); cells rounded, hexagonal, rhombic or elongate-rhomboidal, smooth. Asexual reproduction often by gemmae on main stems, reduced branches, or rhizoids. Dioicous, autoicous, or synoicous. Perichaetia and perigonia on short lateral branches. Setae short or long. Capsules erect or inclined; exothecial cells at times strongly collenchymatous; opercula rostrate; peristome diplolepideous; exostome teeth 16, dorsal (outer) plates thick and cross-striate or thin and pa-pillose, median furrow absent or strongly developed; endostome papillose, basal membranes high or low, segments broad or linear, variously keeled, not or weakly perforate, cilia rudimentary or absent. Ca-lyptrae mitrate, naked or hairy, usually fimbriate-fringed with unicellular or multicellular hairs.

 

 
 
© 2014 Missouri Botanical Garden - 4344 Shaw Boulevard - Saint Louis, Missouri 63110