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Zoogeography
I. Northeastern Pacific
A. Tropical (PANAMANIAN PROVINCE, including "CORTEZ PROV-
INCE")
B. Temperate Region
1. Warm Temperate (CALIFORNIA PROVINCE, including "SAN
DIEGO PROVINCE")
2. Cold Temperate
a. Lower Boreal (OREGON PROVINCE)
b. Upper Boreal (ALEUTIAN PROVINCE)
II. Northwestern Pacific
A. Tropical (INDO-WEST PACIFIC PROVINCE)
B. Temperate Region
1. Warm Temperate (JAPAN PROVINCE)
2. Cold Temperate
a. Lower Boreal (ORIENTAL PROVINCE)
b. Upper Boreal (KURILE and OKHOTSK PROVINCES)
TEMPERATE NORTHEASTERN PACIFIC.—In general, the
boundaries of the various zoogeographic regions and provinces
discussed in this analysis follow the synthesis of Briggs (1974,
see outline above); however, an exception was made with
respect to the southern boundary of the warm termperate
province of the northeastern Pacific. Briggs recognized a
distinct warm temperate province, called the Cortez Province,
1 halfsystem
Pourtales Plan
system
FIGURE 2.—Composite cross-sectional diagram of a calice illustrating various
septal insertion patterns: upper right system with three cycles of septa, upper
left system with four cycles, and lower two systems with various stages of
development of the Pourtales Plan (after Cairns and Parker, 1992). Numbers
refer to cycle to which septa belong.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY
TABLE 3.—Azooxanthellate Scleractinia known from the Gulf of California
Aslrangia haimei Verrill, 1866
Astrangia coslata Verrill, 1866
Astrangia conferia Verrill, 1870a
Paracyathus stearnsii Verrill, 1869
Coenocyalhus bowersi Vaughan, 1906
Ceratotrochus franciscanus Durham and Barnard, 1952
Phyllangia consagensis (Durham and Barnard, 1952)
Desmophyllum dianthus (Esper, 1794)
Balanophyllia cedrosensis Durham, 1947
Endopachys grayi Milne Edwards and Haime, 1848b
Dendrophyllia oldroydae Oldroyd, 1924
Tubastraea coccinea Lesson, 1829
that included the waters of the Gulf of California from La Paz,
Baja California on the west coast of the Gulf to Topolobampo,
Sinaloa, Mexico on the eastern coast. However, most zoogeographers
(e.g., Ekman, 1953; Squires, 1959; Brusca, 1980)
consider the Gulf of California to be an attenuated tropical or
subtropical fauna. This categorization is supported by the
affinities of the 12 azooxanthellate species found in the Gulf
(Table 3). Aside from three species that are cosmopolitan,
seven of the remaining nine species known from the Gulf are
tropical species with their northern limits in the Gulf, or
eurythermic tropical species having their northern limits
slightly farther north in the warm temperate region. Only one
species, Paracyathus stearnsii, is primarily temperate in
distribution, and one species, Ceratotrochus franciscanus, is
endemic to the Gulf. The endemic nature of the latter species
must be viewed with doubt because it is known from only one
specimen.
The northern boundary of the northeastern Pacific warm
temperate California Province is generally regarded as Point
Conception, California, but its southern boundary on the
Pacific coast of Baja California is less well defined. Various
zoogeographers have placed it as far south as Cabo San Lucas
and as far north as Bahia Sebastian Vizcaino (see Briggs,
1974); however, the latitude of Isla Magdalena (24°40'N) is
most often cited, and is adopted in this analysis. At least one
tropical azooxanthellate, Astrangia conferta, has its northern
limit at Isla Magdalena, and this latitude also coincides with the
northern limit of zooxanthellate corals on the northeastern
Pacific coast of Baja California (Squires, 1959; Wilson, 1988,
1991). Seventeen scleractinians are known to occur in the
California Province (Table 4), of which four are cosmopolitan
and one, Crispatotrochusfoxi, has a disjunct distribution in that
province and the Aleutian Province. Two species are endemic
to the province (Nomlandia calif or nica and Dendrophyllia
californica), but both of these are known from very few records.
One species, Leptopenus discus, appears to be bitemperate,
occurring in the northern and southern temperate regions. The
remaining nine species are an almost equal mixture of five
eurythermic tropical species and 4 eurythermic temperate
species, consistent with Briggs' (1974) characterization of this
province as a transition zone between the tropical and
temperate regions. Rocas Alijos, a small group of rocks 343 km
west of Isla MagdaJena at 24°57'N, was included in the warm