January, 2001 IHSN Features Section
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January, 2001 Feature articles Index (All items new this month) Turrids of Taiwan, part 18 by Chen-Kwoh Chang 2 2001 HMS Scholarship Grants 13 Introduction to a Living Mitridae series of articles. See Month section for the first of this series, Mitra 1 14 Molluscs of the Line Islands by Harold G. Jewell Jr. last of series 19 Tetta Richert Obituary 22 Ethnography of Shell Dealers on Oahu, Hawaii 23 Shell Books on line or CD’s 28 NOTE: This section is on line in both HTML and Acrobat versions for only the current month. It is on line in only Acrobat versions for the prior month. In the Acrobat version, the only links that are effec- tive are those in a red box (Links to the General Index). It is recommended that Acrobat users select Bookmarks using an icon on the upper left or in View Menu (AcroRead 3.0 only) . This will give you links to each article or species presented. Viewing at 150 or 200% magnification is recommended for a closer view of the photos. Normally use the hand icon for moving around a page and the left/right arrows on the icon strip at the top of the page to change pages. AcroRead V 3.0 Tools Menu provides a select graphics cursor to outline a graphic that can be copied (Edit menu). AcroRead V 4.0 does not provide for copying graphics. AcroRead V 3.0 is available on IHSN CD. Return to General Index for links to other sections Internet Hawaiian Shell News Page 1 Feature Articles January, 2001 Small Shells of Classic Turridae from Taiwan Part 18 Summary and Discussion of Classification of turrids by Chen-Kwoh Chang* 1373 Phelps Ave., # 8, San Jose, CA 95117 Now, I would like to discuss the status of Ge- nus Taranis. The subfamily location of Genus Ta- Superfamily Level ranis is problematic (Powell, 1966). Powell put it under Turrinae but also suggested using Daphnel- Thiele (1929-1935) moved all the classic Fam- linae. Nordsieck (1977) treated this genus under ily Turridae to Stirps Toxoglossa from Stirps Cytharinae Wenz (= Mangeliinae Powell, 1942). Muricacea. As a matter of fact, prior authors had For these radula-less group of turrids, Taylor et al made a mistake similar to Thiele’s. The previous (1993) conserved Taraninae Casey (1904) in sub- authors kept more than 2000 species of turrids family level under their Family Conidae but were having toxoglossate radula in an improper place, not sure of its status. Muricacea, while Thiele brought nearly 2000 spe- cies of turrids having rachiglossate radula into a wrong home, Stirps Toxoglossa. In this series of In my opinion, it is better to elevate Taraninae articles, I followed Morrison (1966) keeping those from subfamily level to Family level such as Tarani- turrids having Toxoglossate radula in Family Man- dae. My reason is: Families Turridae, Clavidae, geliidae Morrison, 1966 which belongs to Superfa- Pseudomelatomidae and Mangeliidae were sepa- mily Conoidea and moving those having rachiglos- rated by using their typical radula. It is not desir- sate radula away from the Conoidea. able to mix the radula-less turrids with shells hav- A new Superfamily is suggested to house Tur- ing typical radula of either Turridae or Mangelii- ridae, Clavidae and Pseudomelatomidae. This dae. If Taranidae were to be elevated to family new superfamily would not only maintain the tradi- level, its relationship with Families Turridae, Clavi- tion of keeping turrids in one group having the dae, Pseudomelatomidae and Mangeliidae would presence of a posterior sinus but not the presence be similar to the relationship of Family Coralliophi- of marginal radula teeth. The members of Muri- lidae with Families Muricidae and Thaididae. Fam- coidea lack marginal radula teeth ily Coralliophilidae was recognized and there is no reason to refuse this group of shells family level as Taranidae. Thus, the trouble of inserting this group Family Level of shells in Family Turridae or in Family Mangelii- dae as a genus or in a subfamily level in Turridae Chang (1995) followed Morrison (1966) in could be solved. A Key to the Families of Superfa- separating the classic Family Turridae into Families mily Turroidea could be written with simple keys. Turridae, Clavidae, Pseudomelatomidae and Man- Without this change, it is hard to write a satisfac- geliidae based on the types of radula. This pro- tory key to define these groups. duced results similar to Taylor et al (1993) shown in part 1 of this series of articles. This article also suggests that all the radula- less, turrid-like, genera such as Conorbela Powell, 1951, Cenodagreutes E.H. Smith, 1967 and Tereti- Internet Hawaiian Shell News Page 2 Feature Articles January, 2001 Classification of turrids. opsis Kantor & Sysoev, 1989 could be placed in the new, Family “Taranidae”. Key to the Families of the suggested Superfamily 1 Radula, present 2 Radula, absent “Taranidae” 2 Radula, lacking lateral teeth 3 Radula having comb-like laterals; formula 1+1+1(0)+1+1 Clavidae 3 Marginal teeth, wish-bone or duplex type; formula 1+0+1(0)+0+1 Turridae Marginal teeth, pointed and solid, central tooth, rectangular; formula 1+0+1+0+1 Pseudomelatomidae Subfamily Level There are three features of this series of articles concerning the classification by previous authors as follows:: tent characteristics. (1) Subfamilial classification is based on simple (3) Classification is based on the observation shell characters. Keys to subfamilies of families of the specimens of over 1,200 species in my own Turridae and Mangeliidae afforded are practical to collection. The results are obtained by the Induc- use. Powell (1966) classified subfamilies using shell tion Method which is quite different from the De- characters too, but his subfamilies are hard to sepa- duction Method which was used by Taylor et al rate by a key. He proposed his subfamily Conorbii- (1993). They classified their subfamilies by a few nae and subfamily Thatcheriinae without consider- anatomical characters, deducing that the other ing the relationship with the other related subfami- large number of shells of the similar shell charac- lies. ters would have the same anatomy. (2) Separating subfamily levels by using only shell characters after separating family levels by us- Genera Levels ing only radular types. This series of articles never This series of articles realized Laseron’s idea: uses mixed characters in either family level or sub- “A genus is not a natural unit but a term of conven- family level. Hence, it is easy to make keys for both ience to link together a number of related species” family and subfamily levels. McLean (1971) classi- Thus, our classification can greatly reduce using a fied his subfamilies of Family Turridae by both shell subgenus and completely eliminate the section level characters and radular characters. Taylor et al as Thiele (1929-1935) did. However, this article (1993) added anatomical characters in their classifi- still keeps some subgenera as in the following sub- cation. It is hard to avoid overlapping characters in genera level. these systems, I believe. I don’t know how to make a key for their subfamilial classification. Each group such as families or subfamilies should have consis- Shell characters are primarily used for generic Internet Hawaiian Shell News Page 3 Feature Articles January, 2001 Classification of turrids continued classification in this series of articles. Hence, it is opinions of authors for your judgment: easier to place all the genera in their groups. The protoconch has proved of the utmost value in species determination, but when used for generic Subgenera Level differentiation, it must be considered as but one of Subgenera Grouped by Detailed Radular other characters which may be of equal or even Structure greater importance (Laseron, 1958). In part 2, I mentioned my trouble in using the Powell (1942) proposed subgenus Maori- genera proposed to separate species by detailed tomella for species whose protoconch is multispiral radular structure. Both the editor and I hope that (3 or more whorls) and Genus Tomopleura for other malacologists will accept the use of genera those whose protoconch is paucispiral (2 or less based on morphological differences and the use of whorls). subgenera to separate groups by the radula. This Lophiotoma and Lophioturris is another similar would allow the many conchologists to place a pair in which the respective shells appear to be valid species name on their specimens and leave identical except for the protoconch which is mul- subgenera to the professional malacologists. tispiral in the one and paucispiral in the other. The “overlapping” which I mentioned above is another trouble. For example, Calliclava McLean, Laseron (1954) suggested using Genus Nar- 1971 radula have compressed rather than elongate raweena for similar shells in Tomopleura and lateral teeth. This also applies to many popular Maoritomella. Its protoconch has 2-1/2 whorls, genera of Family Clavidae such as Cymatosyrinx, just between paucispiral and multispiral. Elaeocyma, Kylix, Splendrillia etc.. Hence, this series of articles treated Calliclava McLean as a According to Kay (.1979, p. 130) the number subgenus of Genus Cymatosyrinx because Cymto- of whorls of the protoconch may be dependent on syrinx palmeri Dall is the type species of Calli- length of larval life. clava McLean As to Kilburn’s four subgenera of Genus Bathytoma, he (p.636, 1986) specified that Mican- Vaught (1989) had no definite way of separat- tapex Iredale has non-barbed marginals and Para- ing genera. She treated Maoritomella and Tomo- bathytoma has barbed marginals. But it is hard to pleura as separate genera and put Lophiturris as find information about the radula of Bathytoma and synonym of Lophiotoma. Riuguhdrillia. Hence, I treated these subgenera as synonyms of Bathytoma to solve shell workers’ confusion.