42 research outputs found
Magnetic response of magnetic molecules with non-collinear local d-tensors
No full textSchnack J. Magnetic response of magnetic molecules with non-collinear local d-tensors. Condensed Matter Physics. 2009;12(3):323-330.Investigations of molecular magnets are driven both by prospective applications in future storage technology or quantum computing as well as by fundamental questions. Nowadays numerical simulation techniques and computer capabilities make it possible to investigate spin Hamiltonians with realistic arrangements of local anisotropy tensors. in this contribution I will discuss the magnetic response of a small spin system with special emphasis on non-collinear alignments of the local anisotropy axes
Daily Reflections (Meditations) on the Scriptures from the Roman Catholic Lectionary.
No full text"Much will be required of the person entrusted with much, and still more will be demanded of the person entrusted with more." Luke 12:48|I recently attended a "Living Every Day with Passion & Purpose" event with Matthew Kelly, Catholic speaker and author. The above passage resonated with something he said that evening. Kelly told the audience about a clergy who had many people leave the church when they were encouraged to pray for their enemies. During the time when Jesus lived over 2,000 years ago, it could be argued that the popular culture lived by the concept of reciprocal justice or "an eye for an eye." Jesus taught counter-culturally and turned reciprocal justice upside down. Jesus challenged his followers during the Sermon on the Mount: "You have heard that it was said, 'Love your neighbor and hate your enemy.' But I tell you, love your enemies and pray for those who persecute you, that you may be children of your Father in heaven." Matthew 5:43-45 - The Rev. Martin Luther King Jr. once said that "An eye for an eye is a law that makes the whole world blind."|There has been an overwhelming amount of tragic violence these past days and a seemingly ever growing amount of hatred expressed towards those responsible for acts of violence. When we live with hatred and unforgiveness we live with something that is worse than any beating that could be given to the servant who was beating the other servants. Hatred and unforgiveness eats away at us from the inside. Also, in the U.S., the death penalty remains a hot debated topic in current culture. We need to re-evaluate the death penalty according to the consistency of Jesus' message. Jesus lived and died at the hands of capital punishment. His response was to ask for forgiveness because they did not know what they were doing. This brings us back to today's reading found in Luke 12:48: "…more will be demanded of the person entrusted with more." As Christians, we have been entrusted with more and more is demanded from us.|It certainly isn't easy and we can't do it by ourselves. We can follow Abraham's example and by faith, sojourn in the promised land. The promised land where hatred and unforgiveness will be gone. The challenge I have made for myself is the next time I catch myself cursing under my breath towards someone that has irked me (like cut me off in traffic) is to reverse the curse and ask the Holy Spirit to help me pray for the person
Triconia giesbrechti Bottger-Schnack 1999
No full text<i>Triconia giesbrechti</i> Böttger-Schnack, 1999 Pacific form <p>(Figures 9–12)</p> <i>Sampling locality</i> <p> North-east equatorial Pacific (10 ◦ 30 ′ N, 131 ◦ 20 ′ W, 0–100 m).</p> <i>Material examined</i> <p>One female (NIBRIV0000245010) dissected and mounted on 10 slides, collected on 21 August 2009 by D.J. Ham.</p> <p>Three females (NIBRIV 0000245011–13), each dissected and mounted on nine slides. Two males (NIBRIV 0000245014–15), each dissected and mounted on eight or nine slides. All from the sampling locality.</p> <i>Other material examined</i> <p> Three females (NIBRIV0000245021, 24, 25), each dissected and mounted on eight or nine slides. All from the Korea Strait (33 ◦ 44 ′ 50.50 ′′ N, 128 ◦ 15 ′ 39.02 ′′ E), collected on 7 October 2008 by K.H. Cho.</p> <i>Description of female</i> <p> Body length: 519 µm [traditional method: 444 µm] [range: 440–490 µm, <i>n</i> = 7 individuals, based on specimens from the northeast equatorial Pacific; specimens from Korean waters fall into this size range].</p> <p>Exoskeleton heavily chitinized, entire surface covered with numerous deep pits as exemplified for genital double-somite in Figure 13D, E. Prosome 1.6 times length of urosome, excluding caudal rami, about 1.5 times urosome length including caudal rami (Figure 9A). P2-bearing somite without dorsoposterior projection in lateral aspect (Figure 9B). Integumental pores on prosome as indicated in Figure 9A, B. Pleural areas of P4-bearing somite with small pointed posterolateral corners.</p> <p>Genital double-somite 1.7 times as long as maximum width (measured in dorsal aspect) and 1.9 times as long as postgenital somites combined, with oval-rounded form; exoskeleton heavily chitinized (Figure 13D, E), largest width measured at about two-fifths distance from anterior margin, lateral margins rounded, posterior part tapering gradually (Figure 9C). Paired genital apertures located at about two-fifths distance from anterior margin of genital double-somite; armed with one spine and a minute spinule (Figures 9E, arrowed in 13C). Secretory pores on dorsal surface as in Figure 9C.</p> <p>Anal somite slightly wider than long, about 1.5 times longer than caudal rami (Figure 9C, D).</p> <p> Caudal ramus (Figure 9C) about 1.4 times as long as wide; length data of setae II–VII of holotype and two paratype females as shown in Table 1; range of variation of setal lengths relative to longest seta V calculated for two undamaged specimens as follows: II: 6 <i>/</i> 11%, III: 14%, IV: 51 <i>/</i> 52%, VI: 16 <i>/</i> 22%, VII: 31 <i>/</i> 41%.</p> <p> Antennule six-segmented (Figure 10A). Armature formula as for <i>T. pacifica</i>.</p> <p> Antenna three-segmented (Figure 10B), relative lengths (%) of segments approximately 41: 34: 25. Surface of coxobasis covered with numerous deep pits (not illustrated), as on entire exoskeleton. Proximal endopodal segment with double row of denticles on posterior inner margin. Distal endopodal segment with armature and ornamentation as in <i>T. pacifica</i>, except for absence of spinular patch on anterior face of distal endopodal segment.</p> <p> Labrum (Figure 10G, H) similar to that of <i>T. pacifica</i>, except for number of five stout and three small dentiform processes medially along distal margin of each lobe. Anterior surface (Figure 10G) unornamented (lacking integumental pockets and spinular patch). Posterior surface (Figure 10H) with group of three secretory pores located on proximal part of each lobe and additional one on midregion.</p> <p> Mandible (Figure 10C) similar to that of <i>T. pacifica</i>.</p> <p> Maxillule (Figure 10D) similar to <i>T. pacifica</i>, except for slight differences in proportional lengths of elements, with middle element on inner lobe shorter than outermost element and innermost element on outer lobe shorter than the strong element next to the innermost.</p> <p> Maxilla (Figure 10E) similar to that of <i>T. pacifica</i>, except for seta on outer margin of allobasis not reaching as far as tip of allobasal claw.</p> <p> Maxilliped (Figure 10F), with surface of syncoxa sparsely ornamented with spinules. Basis with armature and ornamentation as in <i>T. pacifica</i>, except for fewer spinules between proximal and distal setae (Figure 10F).</p> <p> Swimming legs 1–4 (Figure 11 A–D) with armature and ornamentation as in <i>T. pacifica</i>. Intercoxal sclerites well developed (P1–P3) or narrow (P4) and unornamented. Surface ornamentation on coxae and bases of P1–P4 difficult to discern, possibly as shown in Figure 11 A–D. Coxa of P4 without tuft of setules at outer margin of posterior surface. Surface of distal exopodal and endopodal segments with few secretory pores, as figured.</p> <p>Exopods. Hyaline lamellae on outer spines moderately developed (P1, P2) or narrow (P3, P4). Distal spine about equal in length to (P2) or longer than (P1, P3–P4) distal segment.</p> <p> Endopods. Distal segments of P2–P4 with long, unornamented conical processes at distal margin (Figure 11 B–D). Length data of spines of holotype and three female paratypes as shown in Table 1; length ranges of outer subdistal spine (OSDS) and outer distal spine (ODS) relative to distal spine are as follows: P2 enp-3, OSDS: 88–136%, ODS: 59–91%; P3 enp-3, OSDS: 56–87%, ODS: 44–50%, P4 enp-3, OSDS: 55–59%, ODS: 35–48%. Proportional lengths of outer subdistal spines on P3 and P4 enp-3 different from <i>T. pacifica</i>, being relatively longer. Distal spine much longer than conical process in P2–P4; outer distal spine not reaching as far as tip of conical process in P2–P4; outer subdistal spine not reaching as far as insertion of outer distal spine in P2–P4. Hyaline lamellae on outer spines as in <i>T. pacifica</i>.</p> <p>P5 (Figure 9C, D) with long plumose outer basal seta, about two times longer than outer exopodal seta, reaching far beyond genital apertures and extending as far as four-fifths the length of genital double-somite (Figures 9D, 13E). Exopod a free segment, about as long as wide, bearing short spiniform seta and much longer slender seta, reaching as far as genital apertures; both setae unornamented (Figure 9C, D).</p> <p>P6 (Figures 9E, 13C) armed with one long spine and a minute spinule.</p> <i>Description of male</i> <p> Body length (traditional method): range: 360–414 µm, <i>x</i> = 390 µm, <i>n</i> = 2 individuals. Sexual dimorphism in antennule, maxilliped, endopodal spine lengths on P3 and P4, P5, P6 and in genital segmentation.</p> <p> Caudal rami with length to width ratio as in female; length data of setae II–VII of two male paratypes as shown in Table 1, range of variation of setal lengths relative to longest seta V as follows: II: 9%, III: 13 <i>/</i> 14%, IV: 52 <i>/</i> 58%, VI:14 <i>/</i> 15%, VII: 46–53%, similar to female except for slight difference in proportional lengths of setae VII, being relatively longer than in female.</p> <p>Surface of genital somite covered with numerous deep pits. Secretory pores on dorsal surface as in Figure 12D. Surface ornamentation on genital flaps and on ventral surface of anal segment not fully discerned, probably as indicated in Figure 12E.</p> <p> Antennule (Figure 12B) four-segmented; armature formula as for <i>T. pacifica</i>.</p> <p>Maxilliped (Figure 12G, H) three-segmented. Syncoxa unarmed, single secretory pore on inner distal margin, other surface ornamentation not discernible. Basis robust, with two small naked setae within longitudinal cleft, proximal seta slightly longer than distal one; anterior surface with one to two transverse spinular rows in addition to row of short flat spinules along inner margin, without small expanded flap; posterior face with two to three longitudinal rows of spatulated setules of graduated length (Figure 12H).</p> <p> Swimming legs with armature and ornamentation as in female, length data of endopodal spines of two male paratypes as shown in Table 1; length ranges of outer subdistal spine (OSDS) and outer distal spine (ODS) relative to distal spine as follows: P2 enp-3, OSDS: 93 <i>/</i> 127%, ODS: 67 <i>/</i> 73%; P3 enp-3, OSDS: 54%, ODS: 33 <i>/</i> 35%, P4 enp-3, OSDS: 44 <i>/</i> 50%, ODS: 26 <i>/</i> 32%, slight sexual dimorphism in proportional spine lengths on P3 and P4 enp-3, with OSDS and ODS being relatively shorter than in female.</p> <p>P5 (Figure 12C, D) small exopod not delimited from somite, armature and proportional lengths of exopodal setae as in female; outer basal seta ∼1.4 times longer than outer exopodal seta, relatively shorter than corresponding seta in female.</p> <p>P6 (Figure 12E) represented by posterolateral flap closing off genital aperture on either side; spinular pattern on surface as indicated in Figure 12E. Posterolateral corners distinctly pointed and protruding laterally so that they are discernible in dorsal aspect (Figure 12A, D), occasionally with bifid tip (Figure 12F, arrowed).</p> <i>Remarks</i> <p> Females of <i>Triconia giesbrechti</i> from the Pacific are similar to the typical <i>T. giesbrechti</i> Böttger-Schnack, 1999, originally described from the Red Sea, with regard to almost all morphometric characters including the endopodal spine lengths on P4, which have been found to be of relevance for separating sibling species within this subgroup of <i>Triconia</i> (see above). Slight morphometric differences between the two forms appear to be present in (1) the proportional spine length of the outer subdistal spine on P2 enp-3 not reaching as far as the insertion of the outer distal spine in Pacific specimens, but reaching this point in those from the Red Sea, and (2) the relative length of antennary seta F, being somewhat shorter than seta D and about one-third longer than seta G in the Pacific specimens, whereas seta F is about as long as seta D and twice the length of G in the typical form. However, these small morphometric differences were not regarded as sufficient for establishing a new species for Pacific <i>T. giesbrechti</i>, because (1) the proportional spine lengths of endopodal spine(s) on P2 were found to display considerable variation in Pacific specimens (cf. Table 1), but no corresponding systematic information about the variability of these spines had been gathered for the typical form by Böttger-Schnack (1999), though it was occasionally noted for other species of the <i>dentipes</i> -subgroup by this author, and (2) in the case of proportional lengths of distal antennary setae also the difficulties establishing the correct lengths of these setae due to their curved appearance has to be kept in mind.</p> <p> The ornamentation of the entire exoskeleton with numerous deep pits is likewise found in both form variants of <i>T. giesbrechti</i>, but quite a number of differences in micro-structures of appendages can be found (cf. Table 2), including (1) the additional ornamentation of the antennary coxobasis, (2) the spinular patch either side of the median swelling on the anterior surface of the labrum, (3) the bipinnate ornamentation of the element next to the outermost one on the outer lobe of the maxillule (arrowed in Figure 10D), (4) the ornamentation of the seta on the outer allobasal margin of the maxilla (arrowed in Figure 10E), (5) the spinulose ornamentation of the proximal element on the basis of the maxilliped, which is unornamented in the typical form, and (6) the plumose ornamentation of the outer basal seta on P5, being naked in the typical form.</p> <p> Males of <i>T. giesbrechti</i> have not been recorded before and are described from the equatorial Pacific for the first time. They were identified on the basis of the conspicuous surface ornamentation of the exoskeleton, showing numerous deep pits as in the female, as well as on the proportional spine lengths of the outer basal setae and the two exopodal setae on P5. The sexual dimorphism in the proportional spine lengths on the endopods of P3 and P4, being relatively shorter in the male, is noteworthy. Males of the <i>dentipes</i> -subgroup are difficult to identify because of their great similarity (cf. Böttger-Schnack 1999; Wi et al. 2012), but the distinct surface ornamentation of the entire exoskeleton may be used to separate males of <i>T. giesbrechti</i> from those of the co-occurring <i>T. pacifica</i> and from males of the newly described <i>T. constricta</i> from the Korea Strait (Wi et al. 2012), which otherwise is very similar in morphology. The latter species also differs from the Pacific <i>T. giesbrechti</i> in proportional lengths of the two exopodal setae on P5, in the relative length and the ornamentation of the outer basal seta on P5, being much shorter and unornamented in <i>T. constricta</i>, as well as in proportional spine lengths on P2 enp-3, showing a relatively short outer subdistal spine, which is only about three-quarters the length of the distal spine, while this spine is similar in length or even longer in the Pacific <i>T. giesbrechti</i> (Table 1).</p> <p> Knowledge about the zoogeographical distribution of <i>T. giesbrechti</i> is very limited. In ecological studies, females of this species have been recorded as solitary finds from the north-west subarctic Pacific, Oyashio region, during periods of influence of the Kuroshio current (Nishibe and Ikeda 2004) and they were also identified in the northeast Indian Ocean, at the shelf break of Australia’s North-west Cape (McKinnon et al. 2008) and adjacent to Scott Reef (McKinnon et al. 2013). During a comprehensive study on the species diversity of oncaeid copepods in the Mediterranean Sea, however, <i>T. giesbrechti</i> was not found (Böttger-Schnack and Schnack 2009), which may indicate that the distribution is confined to Indo-Pacific regions. The present record of the species from the tropical and subtropical Pacific Ocean greatly extends the range of zoogeographical distribution in these areas. The distribution of the form variants, however, is unresolved and still needs to be investigated.</p>Published as part of <i>Cho, Kyuhee, Kim, Woong-Seo, Böttger-Schnack, Ruth & Lee, Wonchoel, 2013, A new species of the dentipes-subgroup of Triconia and a redescription of T. giesbrechti and T. elongata (Copepoda: Cyclopoida: Oncaeidae) from the tropical Pacific and the Korea Strait, pp. 1707-1743 in Journal of Natural History (J. Nat. Hist.) (J. Nat. Hist.) 47 (25 - 28)</i> on pages 1730-1738, DOI: 10.1080/00222933.2013.771757, <a href="http://zenodo.org/record/4608159">http://zenodo.org/record/4608159</a>
Developmental trade-offs in Subantarctic meroplankton communities and the enigma of low decapod diversity in high southern latitudes
No full textDevelopmental modes, occurrence and distribution patterns of invertebrate larvae were studied in the Subantarctic Magellan region of South America on the basis of quantitative plankton hauls obtained during the ‘Victor Hensen’ campaign in November 1994. The meroplankton community was found to be numerically dominated by decapod crustacean larvae (47%), followed by polychaetes (20%), echinoderms (16%), cirripedes (8%) and molluscs (7%). A rich decapod community
was detected, with 2 thalassinid, 5 brachyuran, 4 anomuran, 6 caridean, 1 astacid and 1 palinurid species/morphotypes identified. Cluster analyses clearly distinguished deep-water stations (250 to 400 m) south of the Straits of Magellan from shallow-water stations (30 to 100 m) in the Beagle Channel, where meroplankton was dominated by decapod larvae (>90%). Three main larval developmental modes, characterised by morphogenesis, mode of larval nutrition and site of larval development, were observed in Magellan decapods: (1) Extended, planktotrophic development of planktonic larvae; (2) abbreviated, planktotrophic development of planktonic larvae; and (3) abbreviated, endotrophic (lecithotrophic) development of demersally living larvae. Several caridean shrimps with abbreviated larval development, which have congeners in the Antarctic, suggest a strong synchronisation between abbreviated planktotrophic larval development and short periods of primary production. This seems to be an essential factor in early life history adaptation for the colonisation of the Antarctic environment. The impoverished Antarctic decapod fauna, with only a few representatives of caridean shrimp species left, may be related to the lack in flexibility of reptant decapods in distributing energy resources between adults and their offspring, which would allow abbreviated planktotrophic larval development
Approximate eigenvalue determination of geometrically frustrated magnetic molecules
No full textSchnalle R, Laeuchli AM, Schnack J. Approximate eigenvalue determination of geometrically frustrated magnetic molecules. Condensed Matter Physics. 2009;12(3):331-342.Geometrically frustrated magnetic molecules have attracted a lot of interest in the field of molecular magnetism as well as frustrated Heisenberg antiferromagnets. In this article we demonstrate how an approximate diagonalization scheme can be used in order to obtain thermodynamic and spectroscopic information about frustrated magnetic molecules. To this end we theoretically investigate an antiferromagnetically coupled spin system with cuboctahedral structure modeled by an isotropic Heisenberg Hamiltonian
Triconia onnuri Cho & Böttger-Schnack & Kim & Lee 2019, n. sp.
No full textTriconia onnuri n. sp. (Figs 6-9; 13B, C; Tables 2-4) urn:lsid:zoobank.org:act: 515ECE8F-6AAE-47DD-AF7B-55D899441DC7 TYPE LOCALITY. — Northeastern equatorial Pacific Ocean (10°30’N, 131°20’W, 0-100 m). TYPE MATERIAL. — Holotype. 1♀; NIBRIV0000838008; 10°30’N, 131°20’W; 0-100 m; dissected and mounted on 10 slides, collected from the type locality on 21.VIII.2009 by D. J. Ham. Paratypes. 3 ♀; NIBRIV0000838009-011; 10°30’N, 131°20’W; 0-100 m; each dissected and mounted on 9 or 10 slides, respectively (lost a slide of urosome with P5 of the third paratype). — 3 ♂; NIBRIV0000838012-014; 10°30’N, 131°20’W; 0-100 m; each dissected and mounted on 10 slides, respectively. — 4♀, 3♂ kept in one vial in alcohol, MNHN-IU-2019-2283. All specimens are from the type locality. ETYMOLOGY. — The species is named after research vehicle ‘Onnuri’ of the Korea Institute of Ocean Science and Technology (KIOST) to recognize contributions to research activities in the northeastern equatorial Pacific Ocean. DESCRIPTION Female Body length. 784-823 Μm, based on four specimens. Exoskeleton moderately chitinized. Prosome about 1.9 times length of urosome, excluding caudal rami 1.7 times urosome length including caudal rami. P2-bearing somite without conspicuous dorsoposterior projection in lateral aspect (Fig. 6B). Integumental pores on prosome as indicated in Fig. 6A. Pleural areas of P4-bearing somite with rounded posterolateral corners. One pair of secretory pores discernible on first postgenital somite (Fig. 6D). Genital double-somite. 2.0 times as long as maximum width (measured in dorsal aspect) and about 2.2 times as long as postgenital somites combined; largest width measured at anterior one third; posterior part tapering gradually (Fig. 6C); surface covered with numerous minute pores or pits near genital apertures (inset of Fig. 13B). Paired genital apertures located dorsally at about 1/3 of distance from anterior margin of genital double-somite (Fig. 6C); armature represented by one long spine and minute spinule (Fig. 13B). Secretory pores on dorsal surface as indicated in Fig. 6C. Anal somite. About 1.4 times wider than long; slightly longer than caudal rami (Fig. 6C). Ornamentation as in T. komo n. sp. Caudal ramus. About two times as long as wide. Seta VII about half length of seta IV; seta VI almost same length as seta VII, swollen at base (arrowed in Fig. 6F). Antennule (Fig. 7A). 6-segmented. Armature formula as for T. komo n. sp. Antenna (Fig. 7B). 3-segmented. Distal endopod segment with armature and ornamentation as in T. komo n. sp., except for seta I of lateral armature sparsely pinnate, and seta III bipinnate at distal part. Labrum (Fig. 7G, H). Similar to T. komo n. sp., except for each lobe with stronger and fewer dentiform processes than in T. komo n. sp. Mandible (Fig. 7C). Maxillule (Fig. 7D) and maxilla (Fig. 7E) as for T. komo n. sp., except for innermost element on outer lobe of maxillule ornamented with small spinules (arrowed in Fig. 7D). Maxilliped (Fig. 7F). Similar to T. komo n. sp., basis with two bipinnate spiniform elements, nearly equal in length, distal one slightly longer. Distal endopod segment (claw) with row of strong pinnules along proximal 4/5 of concave margin. Swimming legs 1-4. Biramous (Fig. 8 A-D). With armature as in T. komo n. sp. Intercoxal sclerites of P1-P3 ornamented with few spinules on posterior face (Fig. 8A, B, C); intercoxal sclerite of P4 not observed. Coxae and bases of P1-P4 with ornamentation as shown in Fig. 8 A-D. Basis of P4 with outer seta shorter than in T. komo n. sp. (Fig. 8D). Exopods. Similar to T. komo n. sp., except for length of outer spine on P3 exp-1 shorter than in T.komo n. sp. (Fig. 8C). Length ratio of outer spine on exp-1 relative to outer spine on exp-2 of P3 and P4 somewhat smaller than in T. komo n. sp. (Table 3). Endopods. Distal margin of P2-P4 produced into conical process with apical pore. Length ratios of spines different from T. komo n. sp. with length data of spines of five specimens as shown in Table 2; length ranges of outer subdistal spine (OSDS) and outer distal spine (ODS) relative to distal spine (DS) given in Table 3. P5 (Fig. 6E). With outer basal seta very long and plumose at distal part; exopod segment free. Exopod about 1.9 times longer than wide, bearing two naked setae, bearing stout inner seta and extremely long, slender outer seta about twice of length of inner seta, reaching 4/5 the length of genital double-somite from anterior margin, as far as secretory pores on dorsal surface. P6 (Fig. 6F). Represented by operculum closing off each genital aperture, ornamented with long spine and minute spinule (Fig. 13B). Male Body length. 570-604 Μm, based on three specimens. Sexual dimorphism in antennule, maxilliped, P5-P6, caudal ramus, and in genital segmentation. Prosome 1.8 times urosome length, including caudal rami (Fig. 9A). Cephalosome and P1 bearing somite with conspicuous lateral patterns of pore patches (Figs 9B; 13C). Posterior margin of P5-bearing somite with paired row of minute denticles or spinules ventrally (Fig. 9E). Genital somite (Fig. 9D). About 1.5 times longer than wide. Caudal rami. About 1.4 times longer than wide, shorter than in female. Caudal seta with proportional lengths as in female, seta VI swollen at base as in female (arrowed in Fig. 9I). Dorsal surface of genital somite with three secretory pores as indicated in Fig. 9D. Surface of genital flaps ornamented with several rows of small spinules (Fig. 9E, F). Antennule (Fig. 9C). 4-segmented; armature formula as for T. komo n. sp. Maxilliped (Fig. 9G, H). 3-segmented. Surface ornamentation on syncoxa not discernible, except for single secretory pore at inner distal margin. Basis robust, with small naked setae within longitudinal cleft, proximal seta about same length as distal one; anterior surface with one-two transverse spinular rows and row of small flat spinules along inner margin; posterior surface with rows of short spinules of graduated length along palmar margin. Swimming legs. With armature and ornamentation as in female, length data of endopodal spines of three males as shown in Table 2; length ranges of outer subdistal spine (OSDS) and outer distal spine (ODS) relative to distal spine given in Table 4; generally similar to females (cf. Table 3). P5 (Fig. 9D, F). Exopod not delimited from somite, shorter than in female; outer exopodal seta unornamented and almost equal in length to inner seta; outer basal seta naked and much shorter than in female. P6. Represented by posterolateral flap closing off genital aperture on either side; covered by pattern of spinules as shown in Fig. 9E; posterolateral corners protruding laterally and visible in dorsal aspect (Fig. 9A, D). REMARKS Among species of the similis -subgroup of Triconia, T. onnuri n. sp. is closely related to T. similis, based on the body size and the form of the genital double-somite in the female, but differs in the relative lengths of the outer exopodal seta and the outer basal seta on P5, with both setae reaching over half the distance from anterior to posterior margin of the genital double-somite, and the form of caudal seta VI, which is swollen at its base. The combination of these characters separates the new species also from other described species of the similis -subgroup. Furthermore, T. onnuri n. sp. can be identified by the length to width ratio of P5 exopod, which is intermediate (1.9:1) between those of other species of the similis -subgroup (most are less than 1.5:1, except 3: 1 in T. recta); and in some minor differences in the proportional spine lengths on the endo- and /or exopods of P2-P4. Especially on the endopod of P4, the length ratio values of outer subdistal spine (OSDS) relative to distal spine (DS) is higher in T. onnuri n. sp. (OSDS:DS=0.73-0.86:1) than the range of single values reported for T. similis from three studies (OSDS:DS=0.62-0.67:1, Table 3). The male of T. onnuri n. sp. shows a distinct modification of seta VI on the caudal ramus, which is basally swollen (Fig. 8I) as in the female (Fig. 5F). Modifications in the form of caudal setae have not been observed in other species of Triconia so far, but have been reported for other oncaeid species, such as species of Spinoncaea (Böttger-Schnack 2003) and Epicalymma (Böttger-Schnack 2009), where they occur in both sexes as well. Thus, in T. onnuri n. sp., the modification of the caudal setae can be used as an additional tool for separating the species from closely related species within the genus. Also in the male, the proportional spine lengths on the endopod of P2-P4 and the length range of the exopodal spines on exp-1 of P3-P4 are similar to the female. Triconia denticula Wi, Shin & Soh, 2011 (Figs 10-12; Tables 2, 3) Triconia denticula Wi, Shin & Soh, 2011: 590-595, figs 2-4, 9A, B, F (♀). TYPE LOCALITY. — East China Sea (south of Cheju Island) MATERIAL EXAMINED. — East China Sea. 3 ♀; NIBRIV-0000838015-017; each dissected and mounted on 10 slides, respectively; all specimens collected from the northeastern equatorial Pacific Ocean; station BN09-02-01; 10°30’N, 131°20’W, 0-100 m; 21. VII.2009 by D. J. Ham. DESCRIPTION Female Body length. 648-663 Μm, based on three specimens. Exoskeleton moderately chitinized. Prosome about 2.1 times length of urosome, excluding caudal rami 1.9 times urosome length including caudal rami.P2-bearing somite without conspicuous dorsoposterior projection in lateral aspect (Fig. 10B). Integumental pores on prosome as indicated in Fig. 10A. Pleural areas of P4-bearing somite with rounded posterolateral corners. One pair of secretory pores discernible on first postgenital somite (Fig. 10D). Genital double-somite. 1.7 times as long as maximum width (measured in dorsal aspect) and about 2.1 times as long as postgenital somites combined; largest width measured just posterior to mid-level; lateral margins of genital double-somite sinuous anterior to level of maximum width, tapering posteriorly (Fig. 10C); dorsal and lateral surface ornamented with several rows of spinules (Fig. 10C, D); anterior part of genital double-somite protruding dorsally (Fig. 10D). Paired genital apertures located at about 2/5 of distance along genital doublesomite from anterior margin. Paired secretory pores on dorsal surface located at about 2/3 of distance along double-somite from anterior margin (arrowed in Fig. 10C). Anal somite. Slightly wider than long; slightly longer than caudal rami (Fig. 10C). Ornamentation as in T. komo n. sp. (Fig. 10C, D). Caudal ramus. About 1.6 times as long as wide; with seta VII slightly longer than half the length of seta IV and shorter than seta VI (Fig. 10C). Antennule. 6-segmented, armature formula as for T. komo n. sp. (Fig. 11A). Antenna (Fig. 11B). 3-segmented. Distal endopod segment with distal armature consisting of five curved setae, long naked (E), entire unipinnate (A), sparsely pinnate (B-D), setae A-D of graduated length with seta D shortest, and two slender bare setae (F+G), seta G shortest. Labrum (Fig. 11G, H). With medial concavity between lobes covered anteriorly by single long hyaline lamella, lobes with dentiform processes around outer ventral margin more slender than in T. komo n. sp. Anterior surface with paired row of long setules and free margin of integumental pockets either side of median swelling ornamented with minute denticles. Posterior wall of medial concavity ornamented with four long sclerotized “teeth”, posterior surface with group of four secretory pores located on proximal part of each lobe (Fig. 11H). Mandible (Fig. 11C). Maxillule (Fig. 11D) and maxilla (Fig. 11E) as for T. komo n. sp., with slight differences in surface ornamentation of coxa on mandible, and on syncoxa on maxilla. Maxilliped (Fig. 11F). With ornamentation of syncoxa as figured. Basis with two bipinnate spiniform elements, nearly equal in length; fringe of long pinnules between distal seta and articulation with endopod, row of long spinules between proximal and distal setae; short transverse row of long setules near distal seta on anterior surface and additional longitudinal row near outer margin. Distal endopod segment (claw) with row of pinnules along proximal 2/3 of concave margin. Other elements as in T. komo n. sp. Swimming legs 1-4 biramous (Fig. 12 A-D). With armature and ornamentation as in T. komo n. sp. Intercoxal sclerites well developed, without ornamentation. Bases with short (P1, P2, P4) or very long (P3) outer seta. Exopods. With ornamentation similar to T. komo n. sp. Distal spine almost equal in length to (P4) or shorter (P1, P2, P3) than distal exopod segment. Length of exopodal spine on exp-1 and exp-2 of P3 and P4 shorter than in T. komo n. sp. (Fig. 12C, D). Length ratio of outer spine on exp-1 relative to outer spine on exp-2 of P3 and P4 similar to T. komo n. sp. (Table 3). Endopods. Distal margin of P2-P4 produced into conical process (Fig. 12 B-D), process with apical pore. Length data of spines on P2-P4 enp-3 of three specimens as shown in Table 2; length ranges of outer subdistal spine (OSDS) and outer distal spine (ODS) relative to distal spine (DS) given in Table 3. P5 (Fig. 10E). Comprising long plumose outer basal seta and free unornamented exopod segment. Exopod longer than wide, bearing long slender seta (outer seta) ornamented with fine spinules along outer margin and a stout curved seta (inner seta), swollen at base and naked; outer seta about twice longer than inner seta. P6 (Fig. 10C). Represented by operculum closing off each genital aperture, ornamented with spine and minute spinule (visible under light microscope). Male. Unknown REMARKS The original description of T. denticula by Wi et al. (2011) was based on female specimens from the south of Cheju Island of Korea (the East China Sea). As mentioned by Wi et al. (2011), this species closely resembles T. rufa in the form of the genital double-somite and the relative length of the outer basal seta and exopodal setae on P5, but differs: 1) in the absence of the dorsoposterior projection on the P2-bearing somite, which is present in T. rufa, a species of the conifera -subgroup; and 2) in the length to width ratio of P5 exopod, being 1.5 times longer than wide, whereas the length is 2.8 times longer than wide in T. rufa (Böttger-Schnack 1999). Specimens of T. denticula from the northeastern equatorial Pacific Ocean agree in almost all morphological characters with the original description of the species from Korean waters, based on the figures published by Wi et al. (2011). But they exhibited some variability in the length ratio of the prosome to urosome (including CR), with the Pacific specimens being larger (1.9:1) than those in the Korean waters (1.7:1); in the length to width ratio of the genital double-somite, being somewhat more elongate (1.7:1) than in the Korean waters specimens (1.5:1); in the length ratio of the caudal ramus to anal somite, which is shorter (0.6:1) in the Pacific specimens, compared to those in the Korean waters (about same length); and in body size, being somewhat smaller (648-663 Μm) in our study area than in the Korean specimens (660-710 Μm) (cf. Table 3). Wi et al. (2011) mentioned that the exopodal spines on the first exopod segment in P3 and P4 of T. denticula are shortest among the species examined. However, in that study the definition of the proportional lengths of the exopodal spines is not sufficiently clear, as it can be misinterpreted where e.g. “[…] the tip of exopodal spine is reaching […]”. In order to provide more precise information, we calculated the length of the spine on exp-1 relative to the spine on exp-2 of P3 and P 4 in T. denticula from the Korean waters (paratype) in NIBR and from the Pacific Ocean. We also measured the lengths of the endopodal spines on P2-P 4 in specimens of the two areas. The resulting length ratios are given in Table 3. The recalculated ratio values for Korean specimens are largely overlapping with the range of values reported for specimens from the equatorial Pacific Ocean; only the ratio values for spines on P2 enp-3 are not completely overlapping and are tentatively higher for Korean specimens than for the open Pacific specimens. T. denticula from the Korean waters described by Wi et al. (2011) exhibited numerous small scales on the surfaces of the genital double-somite, the anal somite and the caudal ramus, which were discerned by a using scanning electron microscope. Actually, these structures are hardly discernible with a light microscope due to their small size. In the Pacific specimens, the surface ornamentation of the genital double-somite was probably not fully discerned, but just on the dorsolateral part at half length of the genital double-somite. Also, T. denticula specimens from the two areas seemed to differ in the position of paired integumental pores on the dorsal surface of the genital double-somite, which are located at approximately 2/3 of distance along genital double-somite from anterior margin in the Pacific specimen and in the same vertical line with the genital apertures (cf. Fig. 9A, C), while in the specimen from the Korean waters they were figured as being situated at about half the distance along the genital double-somite from anterior margin and much closer to the lateral margin of the double-somite (Wi et al. 2011: fig. 3C). However, upon reexamination of the undissected female paratype of T. denticula (NIBRIV0000214678) during the present study, it was found that the position of paired integumental pores was similar to their position in the Pacific specimens. The type material of T. denticula from the Korean waters which was loaned from the collections of NIBR and reexamined by the senior author of the present study turned out to be insufficient for taxonomic comparisons due to the following reasons: 1) The holotype sample (NIBRIV0000214676) nominated as: “ Holotype female dissected and mounted on 1 glass slide” (Wi et al. 2011: 590) was found to contain an undissected female specimen of the dentipes -subgroup of Triconia on this slide. 2) The first paratype sample (NIBRIV0000214677) nominated as: “ 2 females dissected and mounted on 3 slides”, was in very poor condition and it was difficult to make out the contents on the slides. Recognizable contents were present in only one of the three slides. 3) The second paratype sample (NIBRIV0000214678) nominated as: “[…] 2 undissected females in 1 vial […]” (Wi et al. 2011: 590) included one female of T. denticula and one female of a species of the dentipes -subgroup of Triconia. In conclusion, a fundamental revision of the type material of T. denticula is required. Triconia denticula Wi, Shin & Soh, 2011 (Figs 10-12; Tables 2, 3) Triconia denticula Wi, Shin & Soh, 2011: 590-595, figs 2-4, 9A, B, F (♀). TYPE LOCALITY. — East China Sea (south of Cheju Island) MATERIAL EXAMINED. — East China Sea. 3 ♀; NIBRIV-0000838015-017; each dissected and mounted on 10 slides, respectively; all specimens collected from the northeastern equatorial Pacific Ocean; station BN09-02-01; 10°30’N, 131°20’W, 0-100 m; 21. VII.2009 by D. J. Ham. DESCRIPTION Female Body length. 648-663 Μm, based on three specimens. Exoskeleton moderately chitinized. Prosome about 2.1 times length of urosome, excluding caudal rami 1.9 times urosome length including caudal rami.P2-bearing somite without conspicuous dorsoposterior projection in lateral aspect (Fig. 10B). Integumental pores on prosome as indicated in Fig. 10A. Pleural areas of P4-bearing somite with rounded posterolateral corners. One pair of secretory pores discernible on first postgenital somite (Fig. 10D). Genital double-somite. 1.7 times as long as maximum width (measured in dorsal aspect) and about 2.1 times as long as postgenital somites combined; largest width measured just posterior to mid-level; lateral margins of genital double-somite sinuous anterior to level of maximum width, tapering posteriorly (Fig. 10C); dorsal and lateral surface ornamented with several rows of spinules (Fig. 10C, D); anterior part of genital double-somite protruding dorsally (Fig. 10D). Paired genital apertures located at about 2/5 of distance along genital doublesomite from anterior margin. Paired secretory pores on dorsal surface located at about 2/3 of distance along double-somite from anterior margin (arrowed in Fig. 10C). Anal somite. Slightly wider than long; slightly longer than caudal rami (Fig. 10C). Ornamentation as in T. komo n. sp. (Fig. 10C, D). Caudal ramus. About 1.6 times as long as wide; with seta VII slightly longer than half the length of seta IV and shorter than seta VI (Fig. 10C). Antennule. 6-segmented, armature formula as for T. komo n. sp. (Fig. 11A). Antenna (Fig. 11B). 3-segmented. Distal endopod segment with distal armature consisting of five curved setae, long naked (E), entire unipinnate (A), sparsely pinnate (B-D), setae A-D of graduated length with seta D shortest, and two slender bare setae (F+G), seta G shortest. Labrum (Fig. 11G, H). With medial concavity between lobes covered anteriorly by single long hyaline lamella, lobes with dentiform processes around outer ventral margin more slender than in T. komo n. sp. Anterior surface with paired row of long setules and free margin of integumental pockets either side of median swelling ornamented with minute denticles. Posterior wall of medial concavity ornamented with four long sclerotized “teeth”, posterior surface with group of four secretory pores located on proximal part of each lobe (Fig. 11H). Mandible (
About a detail in the didactic treatment of tetrasomic segregation
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Revisiting and modeling the magnetism of hole-doped CuO 2 spin chains in Sr 14−x Ca x Cu 24 O 41
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