Occurrence and Distribution of the Genus Jania J. V. Lamouroux (Corallinales, Rhodophyta) in the Pacific Coast of Baja California and Gulf of California, Mexico

This paper provides a description of the articulated species of the Tribe Janieae (Corallinales, Rhodophyta) in the Pacific coast of Baja California and Gulf of California, Mexico. This taxonomic report is based on newly collected data in the study area and material currently housed at several herbaria. As a result of the present study, the record of the tribe Janieae is represented at the Pacific coast of Mexico for one genus: Jania J. V. Lamouroux with nine species. Morphological, reproductive and anatomical descriptions are provided in detail. In addition, keys for determination are included, as well as habitat, nomenclature, comparisons with other species and information on distribution. Instead of eleven species of Jania currently recorded for the study area, we recognize only nine. Jania verrucosa is restricted to the occidental coast from the Peninsula of Baja California. The remainder of the species commonly occurs in the Gulf of California and the Pacific coast of Baja California’s Peninsula. On the other hand, the gametangial thalli of J. adhaerens and tetrasporangial conceptacle in J. longiarthra are reported for the first time in Mexico.


Introduction
All members of the subfamily Corallinoideae (J. E. Areschoug) Foslie are constructed of uncalcified genicula and calcified intergenicula and form branched fronds. The Tribe Corallineae J. E. Areschoug is characterized by genicula consisting of a single uncorticated and uncalcified tier of medullar cells and lateral cellular fusion. The genera of the Corallinoideae are referred to two tribes: the Corallineae and the Janieae, which are delimited on the basis of morphological and reproductive features [1,2]. The Janieae is distinguished from the Corallineae by reproductive characteristics, such as thick, compact carposporophytic fusion cells bearing marginal carposporangial filaments, male conceptacles with narrow chambers and short canals, and a comparatively small number of sporangia in each tetrasporangial conceptacle [3]. The tribe Janieae includes one genus: Jania J. V. Lamouroux. The genus Jania is an important component of the marine benthic flora in the Gulf of California. How-ever, in spite of their abundance, representatives of this genus have received little attention. The aim of this paper is to provide morphological, anatomical and reproductive accounts of this genus. Distinctive field characters as well as pertinent photographs are provided for each species.
Occurrence and Distribution of the Genus Jania J. V. Lamouroux (Corallinales, Rhodophyta) in the Pacific Coast of Baja California and Gulf of California, Mexico 2 samples of general collections collected by reef-walking or snorkeling at Loreto, Bahia Agua Verde and La Paz. Samples were preserved in 5% formalin/seawater. Preserved specimens were decalcified with 0.6 M HNO 3 . Small segments were stained with aniline blue and hematoxilin-eosine for anatomical observations and measurements.
The classification system of Abbott and Hollenberg [5] and Guiry and Guiry [6], are used throughout this paper. In cell measurements length denotes the distance between primary pit connections whereas diameter denotes the maximum width of the cell lumen at right angles to this. Conceptacle measurements follow the system of Johansen [7], Adey and Adey [8]. Descriptive terminalogy follows Johansen and Silva [1] and Abbott and Hollenberg [5]. Pertinent remarks about the morphology, detailed descriptive accounts, and specimens examined are provided for each species. In this study we made observations on a total of 80 specimens are housed at herbaria ENCB and CMMEX. Description of the vegetative, reproductive characters and information related to the habitat, the geographic distribution and examined specimens are included for each species.

Results
Nine species representing genus Jania were found during the present study.
1) Jania J. V. Lamouroux 1812 [9] Calcified articulated algae of erect fronds that are primarily dichotomously branched, attached by minute to small crustose holdfast and stolon-like holdfasts. Intergenicula are cylindrical, subcylindrical or compressed, and smooth, winged or lobed. The intergenicula is usually considerably longer than broad, and composed of arching tiers of medullary cell, an outer cortex of pigmented cells, and external single-layer of epithallial cells. Medullary cells in tiers that are all the same height. Cells are with pit-connections. Trichocytes present, but not always evident. Genicula (joints) uncalcified, and consist of a single tier of long, straight cells (sometimes partially covered by overlapping calcification of intergenicula). Sporangial conceptacles contain up to 12 (−15) tetrasporangia or bisporangia. Conceptacles are solitary and terminals with an apical pore, sometimes the conceptacles give rise to new branches, so they are called antenniferous. Carposporangial conceptacles with narrow (to 35 µm), wide (to 130 µm) fusion cells. Spermatangial conceptacles long and narrow, lanceolate; spermatangia along inner walls of chamber.
Habitat: usually growing among other turf-algae, sometimes on rocks or epizoic on sponges; intertidal. Distribution
Habitat: Growing among other turf algae; mid to low intertidal.
Anatomy: In longitudinal section cells of the medulla 10 -12 m breadth and 18 -30 m length, cortical region composed by 1 -2 layers of cells, these of 5 -6 m breadth.

Discussion
The genus Jania is widely distributed in tropical and subtropical waters of the planet [45]. The total number of described species of this genus is controversial, are considered from 20 -70 [46,47]. According to Johansen and Womersley (1994) [48], many species need to be reexamined due to inappropriate diagnosis or nomenclatural problems. During the analysis of articulate coralline Jania from the shores of the Gulf of California was verified the presence of four taxa. It was established that several species have problems for correct recognition. There are also other species have been recorded for the Gulf of California, but could not confirm its presence, as in the case of Jania decussata-dichotoma Yendo, two samples were reviewed, but these are very close to Jania adhaerens. In fact, Johansen (1970) [7], Yoshida (1998) [49], and Price and Scott (1992) [24] have considered J. decussato-dichotoma conspecific with J. adhaerens. Jania huertae, was described from the northern Gulf, and is only known from the type specimen. (Chávez-Barrera 1972) [50]. Unfortunately, the type is lost and during this study we did not find specimens that confirm the presence of this taxon in the study area. In addition to reviewing the original description of J. huertae, it seems to be closely related to J. longiarthra, mainly in the morphology of both species. Furthermore, J. huertae was described based only on morphological characteristics and reproductive structures were not reported, by this reasons in this study we considerer J. huertae as a doubtful record, until locate the type specimen or find samples that are consistent with the characteristics of J. huertae.

Conclusion
Relationships among the species of Jania are very complex, and our morphological data indicate that the species of Jania could be delineated by the branching pattern of the main axes, intergenicular shape, and conceptacle position. However, the information provided by the analysis of vegetative and reproductive characteristics is not enough, so it requires molecular studies to achieve a more consistent classification of this genus.

Acknowledgments
Thanks to the Instituto Politécnico Nacional and the Universidad Autónoma de Baja California for the support granted to this study. Thanks to the Operation and Development Committee of Academic Activities-IPN for support to the first and second author. Carlos A. Sánchez Mendoza designed plates.