Cradoscrupocellaria Vieira, Spencer Jones & Winston, 2013

VIEIRA, LEANDRO M., JONES, MARY E. SPENCER & WINSTON, JUDITH E., 2013, <p class = " HeadingRunIn " align = " left "> <strong> <em> Cradoscrupocellaria </ em>, a new bryozoan genus for <em> Scrupocellaria bertholletii </ em> (Audouin) and related species (Cheilostomata, Candidae): taxonomy, biodiversity and distribution </ strong> </ p>, Zootaxa 3707 (1), pp. 1-63 : 5-7

Family Candidae d’Orbigny, 1851

Genus Cradoscrupocellaria Vieira, Spencer Jones & Winston n. gen.

Type species. Acamarchis bertholletii Audouin, 1826 , by original designation.

Synonym. Crisina van Beneden, 1850 , nomen oblitum (not Crisina d’Orbigny, 1850 , nomen protectum)

Etymology. Greek krados, branch, alluding to the characteristic branched scutum of some species previously assigned to Scrupocellaria van Beneden, 1845 .

Diagnosis. Biserial member of the family Candidae with articulated unbranched distal spines, branched scutum inserted at midline of inner edge of opesia, rounded to trapezoidal vibracular chamber, single axial vibraculum and ooecium perforated by ectooecial pores.

Description. Candidae with almost-straight branches, with chitinous joints passing across opesia or below it in zooids C and D at bifurcation; zooids with articulated distal spines, unbranched. Frontal avicularia often present and dimorphic, aquiline to elongate, with serrated rostrum and hooked mandible. Frontal scutum delicate or stout, forked to highly branched with truncate or acute tips, inserted at midline of inner edge of opesia and overarching frontal membrane; scutum occasionally absent. Distolateral avicularium often present at outer distal corner of zooid, placed laterally or behind spines. Vibracular chamber subrounded to trapezoidal, setal groove transverse to internode axis, with smooth seta. Axial vibraculum single, without rhizoidal foramen. Ooecium perforated by rounded ectooecial pores.

Remarks. Insofar as Scrupocellaria van Beneden, 1845 comprised species with a mixture of characters, Vieira et al. (in press) resurrected and redefined Licornia van Beneden, 1850 to accommodate some of them.

The perforated ooecium, branched scutum and rounded to trapezoidal vibracular chamber with its setal groove transverse to the internode axis distinguish Cradoscrupocellaria n. gen. from the characters observed in the type of Scrupocellaria , Scrupocellaria scruposa ( Linnaeus, 1758) . The shape of scutum, regularly branched, and shape of the vibracular chamber, with a transverse setal groove are also distinct from the equivalent characters in Licornia (see Vieira et al. in press). These morphological characteristics, clearly observed in Scrupocellaria bertholletii and reported in Scrupocellaria reptans (see Vieira & Spencer Jones 2012), lead us to erect a new genus to include nine species previously assigned to Scrupocellaria : Cradoscrupocellaria bertholletii ( Audouin, 1826) n. comb., Cradoscrupocellaria curacaoensis ( Fransen, 1986) n. comb., Cradoscrupocellaria ellisi ( Vieira & Spencer Jones, 2012) n. comb., Cradoscrupocellaria hirsuta ( Jullien & Calvet, 1903) n. comb., Cradoscrupocellaria macrorhyncha ( Gautier, 1962) n. comb., Cradoscrupocellaria nanshaensis ( Liu, 1991) n. comb., Cradoscrupocellaria reptans ( Linnaeus, 1758) n. comb., Cradoscrupocellaria serrata ( Waters, 1909) n. comb. and Cradoscrupocellaria tenuirostris ( Osburn, 1950) n. comb. Another 18 new species are described in this paper.

Scrupocellaria bellula Osburn, 1947 is also characterized by ovicells with ectooecial pores, trapezoidal vibracular chamber and branched scutum; this species is not reassigned to Cradoscrupocellaria , however, because of its distinctive growth pattern—colonies are apparently unbranched, but rarely have a chitinous joint crossing the gymnocyst of a single zooid at the new branch—and because of the presence of branched distal spines, absent in Cradoscrupocellaria species. The scutum of S. bellula is also distinct in having 12–30 acute tips and covering almost the entire frontal membrane ( Fig. 1 ).

Licornia resembles Cradoscrupocellaria in having porous ovicells but is distinguished by its branched oral spines, unbranched scuta and the shape of its basal vibracular chambers with the setal groove oblique to the internode axis. Some other species of Scrupocellaria also have porous ovicells, e.g. Scrupocellaria frondis Kirkpatrick, 1890 and Scrupocellaria sinuosa Canu & Bassler, 1927 (see Tilbrook & Vieira 2012), but they are distinguished from Cradoscrupocellaria in having broad paddle-shaped scuta and monomorphic frontal avicularia.

Van Beneden (1850) erected the genus Crisina for Crisie rampante (= Sertularia reptans Linnaeus ) and Acamarchis bertholetii (sic) Audouin. This name has not been used in the literature since Harmer (1926), who included Crisina van Beneden as junior synonym of Scrupocellaria van Beneden, 1845 ; thus, Crisina van Beneden is a lapsed name. On the other hand, the homonym Crisina d’Orbigny, 1850 has been used for some fossil cyclostomes in the last two centuries (e.g. d’Orbigny 1853; Beissel 1865; Gabb & Horn 1862; Stoliczka 1865; Hamm 1881; Smitt 1872; Jullien 1882; Waters 1884; Marsson 1887; MacGillivray 1895; Gregory 1899; Neviani 1900; Harmer 1915; Canu 1920; Borg 1941; Brood 1972, 1976).

Crisina d’Orbigny was published in 1850 in the “ Prodome de Paléontologie ”; though dated 1849, it was possibly published in January 1850 (Dennis P. Gordon & Paul D. Taylor, pers. comm.), whereas Nomenclator Zoologicus has November 1850 ( Neave 2012). Crisina van Beneden was also published in a work dated 1849 that was also published in 1850, but no exact date is known for the issue. To promote the stability and according to ICZN Article 23.2, we consider the unused homonym Crisina van Beneden, 1850 as a nomen oblitum and the homonym Crisina d’Orbigny, 1850 is declared a nomen protectum.

Species with slender scutum and acute tips

Figures

FIGURE 1. Scrupocellaria bellula Osburn, 1947. A–D, Uncatalogued specimen (part of AMNH 1518.1), Jamaica. A, Frontal surface of branch with ovicelled zooids. B, Close-up of two ovicelled zooids; note the branched frontal scutum and small frontal avicularium on zooids. C, Frontal surface of branch; note the presence of seven distal spines. D, Close-up of frontal surface of autozooid.