Two New Shallow Water Sea Anemones of the Family Actiniidae (Cnidaria: Anthozoa: Actiniaria) from British Columbia (NE Pacific)
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Invertebrate Zoology, 2013, 10(2): 199216 © INVERTEBRATE ZOOLOGY, 2013 Two new shallow water sea anemones of the family Actiniidae (Cnidaria: Anthozoa: Actiniaria) from British Columbia (NE Pacific) N.P. Sanamyan1, K.E. Sanamyan1, N. McDaniel2 1 Kamchatka Branch of Pacific Geographical Institute, Far-Eastern Branch of the Russian Academy of Sciences, Partizanskaya Str. 6, 683000 Petropavlovsk-Kamchatsky, Russia. e-mail: [email protected] 2 Neil McDaniel, Vancouver, British Columbia, Canada. e-mail: [email protected] ABSTRACT: Urticina clandestina sp.n. and Aulactinia vancouverensis sp.n. (family Actiniidae) are recorded from British Columbia, Canada. Urticina clandestina sp.n. is unique in possessing gonads on all mesenteries of first cycles and thus attaining intermediate position between Urticina and Cribrinopsis. Aulactinia vancouverensis sp.n. is a medium- sized rose-coloured species abundant near the northern end of Vancouver Island, but not widespread in southern British Columbia waters. It posses holotrichs in the column; their occurrence in related species is discussed. How to cite this article: Sanamyan N.P., Sanamyan K.E., McDaniel N. 2013. Two new shallow water sea anemones of the family Actiniidae (Cnidaria: Anthozoa: Actiniaria) from British Columbia (NE Pacific) // Invert. Zool. Vol.10. No.2. P.199216. KEY WORDS: Sea anemones, Northeast Pacific, Actiniidae, Cnidaria, Anthozoa, Actiniaria, Urticina clandestina, Aulactinia vancouverensis. Äâà íîâûõ ìåëêîâîäíûõ âèäà àêòèíèé ñåìåéñòâà Actiniidae (Cnidaria: Anthozoa: Actiniaria) èç Áðèòàíñêîé Êîëóìáèè (ñåâåðî-âîñòî÷íàÿ Ïàöèôèêà) Í.Ï. Ñàíàìÿí1, Ê.Å. Ñàíàìÿí1, Í. ÌàêÄåíèåë2 1 Êàì÷àòñêèé ôèëèàë Òèõîîêåàíñêîãî èíñòèòóòà ãåîãðàôèè ÄÂÎ ÐÀÍ, óë. Ïàðòèçàíñêàÿ, 6, Ïåòðîïàâëîâñê-Êàì÷àòñêèé 683000, Ðîññèÿ. e-mail: [email protected] 2 Í. ÌàêÄåíèåë, Âàíêóâåð, Áðèòàíñêàÿ Êîëóìáèÿ, Êàíàäà. e-mail: [email protected] ÐÅÇÞÌÅ: Urticina clandestina sp.n. è Aulactinia vancouverensis sp.n. (ñåìåéñòâî Actiniidae) îïèñàíû èç ðàéîíà Áðèòàíñêîé Êîëóìáèè, Êàíàäà. Urticina clandestina n.sp. çàíèìàåò ïðîìåæóòî÷íîå ïîëîæåíèå ìåæäó ðîäàìè Urticina è Cribrinopsis èç- çà íàëè÷èÿ ãîíàä íà âñåõ ìåçåíòåðèÿõ, â òîì ÷èñëå è ïåðâûõ öèêëîâ, ÷òî íå õàðàêòåðíî äëÿ ðîäà Urticina. Aulactinia vancouverensis sp.n. àêòèíèÿ ñðåäíåãî ðàçìåðà, ðîçîâîãî öâåòà, âñòðå÷àþùàÿñÿ â áîëüøîì êîëè÷åñòâå ó ñåâåðíîé ÷àñòè î. Âàíêóâåð, íî íå øèðîêî ðàñïðîñòðàíåííàÿ â âîäàõ Áðèòàíñêîé Êîëóìáèè. Ó íåå îáíàðóæåíû ãîëîòðèõè â íèæíåé ÷àñòè êîëþìíà. Îáñóæäàåòñÿ âñòðå÷àåìîñòü ýòèõ íåìàòîöèñò â ðîäñòâåííûõ âèäàõ. 200 N.P. Sanamyan, K.E. Sanamyan, N. McDaniel Êàê öèòèðîâàòü ýòó ñòàòüþ: Sanamyan N.P., Sanamyan K.E., McDaniel N. 2013. Two new shallow water sea anemones of the family Actiniidae (Cnidaria: Anthozoa: Actiniaria) from British Columbia (NE Pacific) // Invert. Zool. Vol.10. No.2. P.199216. ÊËÞ×ÅÂÛÅ ÑËÎÂÀ: àêòèíèè, ñåâåðî-âîñòî÷íàÿ Ïàöèôèêà, Actiniidae, Cnidaria, Anthozoa, Actiniaria, Urticina clandestina, Aulactinia vancouverensis. Introduction photographs of living species are a very impor- tant part of species descriptions, which may Actiniid sea anemones (members of the fam- assist to identify the species in the future. In ily Actiniidae) are a diverse group represented some species the colour model is more stable, in by many species in cold and temperate waters of others more variable, so in each case it is neces- the North Pacific. Many species of this group sary to take into account a whole complex of are large and colourful and constitute probably features characteristic of the species. the most eye-catching component of benthic Numerous underwater photographs of sea faunae at diver accessible depths. Despite a long anemones taken by one of us (N. McDaniel) in history of investigation the taxonomy and spe- British Columbia revealed that sea anemones in cies assignment of many North Pacific actiniid this region are more diverse than was thought sea anemones is still confused with a number of previously, with several species which have not mis-identifications and misapplied names es- been assigned to any previously known species. tablished in the literature (see Sanamyan, San- Two of them are described in the present paper. amyan, 2006). In part this is a result of objective difficulties in the identification of preserved Material and methods specimens, which lose some species-specific characters (e.g. colour, shape of the tentacles, Numerous specimens of both species de- etc.), by which living specimens could be easily scribed in the present paper were observed and separated, and in part a result of incorrect inter- photographed in-situ underwater to record co- pretation of features and older descriptions (e.g. lour, external appearance, position on substrate nematocyst batteries of Cnidopus were com- and to assess the degree of variation in these pared with occasional occurrence of similar features. To study morphology collected speci- nematocysts in Epiactis resulting in incorrect mens were relaxed in seawater with a bit of clove uniting of these genera, see Sanamyan, Sanamy- oil and fixed with formalin. For long term storage an, 1998). the specimens were transferred to alcohol. Underwater photography has advanced To prepare histological sections the isopro- greatly in recent years, with well-documented, panol-mineral oil technique was used (Buesa, high quality photographs of sea anemones in Peshkov, 2009; Sanamyan, Sanamyan, 2012). their natural environment now available to tax- This technique is much easier, faster and pro- onomists. This has significantly improved our duces better results than traditional methods knowledge of distribution, range of variation which use xylene. The method includes dehy- and habitat for many species of shallow water dration of a specimen in five changes of 100% sea anemones. For example, it became clear that isopropanol, then two changes of isopropanol although the colouration of many species of sea mixed with mineral oil (5:1 and 2:1 at 50°C), anemones varied considerably, the colour pat- then mineral oil at 50°C, and finally three changes tern of almost every species has some rather of paraffin at 5558°C. Each stage took from 15 stable species-specific features. This especially min to 2 hours depending on the size of the applies to various kinds of colour markings on specimen (usually pieces less than 1 cm in the disk and tentacles. We believe that colour thickness were used). For general histology 4 Two new shallow water sea anemones of the family Actiniidae 201 mm sections were stained by one of several type) and 57 x 42 mm ($) and 55 x 32 mm (#) variants of Masson trichrome (Llewellyn, 2013) (paratypes). The column is cylindrical; the cir- depending on which dye produced better results cular adhesive pedal disk is usually of about the in a particular specimen or tissue. To study the same diameter as the column. The column has distribution of nematocysts 10 mm sections were numerous adhesive verrucae which are present over the whole of its surface but more numerous stained first with 1% water solution of basic dye and more prominent in the distal half. All three (e.g. Safranin which stains basitrichs and some preserved specimens bear a belt consisting of types of holotrichs red, or Toluidine blue which large and crowded gravel particles and broken stains the same cnidae black or deep blue), shell firmly attached to verrucae on distal half of differentiated in slightly acid water (until stain column, although the region near the margin is is washed out from all tissues and only nemato- almost free of foreign matter (Fig. 1A, B). cysts remain stained), then the stain is fixed in Verrucae, to which gravel particles are attached, 1% phosphomolybdic acid, and then the mesog- have a thin cuticular covering (Fig. 2C). The loea may be stained by Aniline blue or Fast colour of the pedal disk and column is usually green FCF. We find this method very useful to red, sometimes pink, in the holotype it was reveal the real distribution of nematocysts in bright vermilion red, darker at distal column; verrucae are of the same colour as the rest of various tissues. column without any markings of different co- Size ranges of cnidae were studied on small lour. There is a deep fosse and short capitulum pieces of macerated tissue. Cnidae were mea- (a feature characteristic of many actiniids). sured according the method of Hand (1954) (the The oral disk is flat and circular. All three reasons why we prefer this method are de- preserved specimens have about 160 tentacles scribed in Sanamyan, Sanamyan, 2013). and on numerous underwater photographs from Cnidae terminology follows Weill (1934) 100 to 160 tentacles are visible. The tentacles and Carlgren (1949), but classification of p- are always arranged decamerously in five cycles mastigophores follows Schmidt (1969, 1972, on outer half of the oral disk. They are short, 1974) with the modification of Hartog (1995) occasionally, in extension, as long as half the (see Sanamyan et al., 2012 for details). diameter of oral disk, but usually much shorter, Holotypes will be kept in Zoological Insti- and thick, with blunt rounded tips, all of about tute (St. Petersbourg, ZIN), paratypes in Kam- the same length, inner may be slightly thicker chatka Branch of Pacific Geographical Institute than outer. In preserved specimens the tentacles (Petropavlovsk-Kamchatsky, KBPGI). are longitudinally striated. Underwater photo- Taxonomy graphs of living specimens display considerable variation of colour and shades of oral disk and tentacles but a colour model is more or less Family Actiniidae stable and characteristic. The background co- lour of the oral disk varies from bright to dull Urticina clandestina sp.n. red, olive-green, gray, blue or dirty yellow. The Table 1; Figs. 14. bases of the tentacles of some specimens are outlined by short thin red radial lines running on MATERIAL EXAMINED. Holotype: ZIN No. 11328, the oral disk. In some specimens these lines may according to the incoming catalog at the Sponges and Coelenterates Department of ZIN RAS, British Columbia, be quite well developed (Fig. 1C), in others they Canada: southern Strait of Georgia at the south end of Thetis are feebly marked or even absent (Fig.