Cryptic species of the gobioid paedomorphic genus <Emphasis Type="Italic">Schindleria</Emphasis> from Palau,Western Pacific Ocean

The extremely paedomorphic fish Schindleria (Gobioidei, Schindleriidae) is widely distributed in the Indo-Pacific Ocean, inhabiting coral reef lagoons. At least 21 cryptic species (Schindleria spp. 1–21) have been discovered around the Ryukyu and Ogasawara Islands. As a first step in extending the survey areas to the entire Indo-Pacific Ocean, the present study collected and examined Schindleria in Palau, located approximately 2,200 km from the Ryukyu Islands, for any cryptic diversity. Molecular phylogenetic analysis using partial mitochondrial 16S rRNA sequences of 71 specimens revealed four new cryptic species of Schindleria spp. 22–25 (Palau 1–4) in Palau.     

Lipids of the notothenioid fishes Trematomus spp. and Pagothenia borchgrevinki from East Antarctica

The notothenioid fishes Trematomus pennellii, T. newnesi, and T. bernacchii had 5–15% skeletal lipid, as percent dry weight, and this comprised 6–8% of the total body lipid. Trematomus hansoni and Pagothenia borchgrevinki had 2–4% skeletal lipid, which comprised 1% of total body lipid. Triacylglycerol was the major lipid class present in all tissues of all fish analyzed (up to 89% of total lipid), with minor components including sterol, phospholipid and wax esters. Monounsaturated fatty acids comprised 38.3–58.0% of the total fatty acids, and included primarily oleic [18 : 1(n-9)] and palmitoleic [16 : 1(n-7)] acids. Polyunsaturated fatty acids comprised 19.1–40.0% of the total fatty acids and included primarily eicosapentaenoic acid [20 : 5(n-3)] and docosahexaenoic acid [22 : 6(n-3)]. These five notothenioid fishes, which include benthic, benthopelagic, and cryopelagic species, are lower in lipid than other important Southern Ocean fishes (such as the Patagonian toothfish) and are estimated to be negatively buoyant. These data will be of use to research groups presently using signature lipid methodology. Accepted: 5 April 1999     

Temperature-dependent conduction properties in Arctic fish peripheral nerves

The conduction properties of peripheral nerves from the Arctic fish species Arctic eelpouts (Lycodes sp.), snake blenny (Lumpenus lampretaeformis) and polar cod (Boreogadus saida), permanently adapted to low temperatures, were studied. Nerves of these fishes have two types of fibres, characterised by extracellular compound action potentials with fast (7 m/s) and slow (4 m/s) conduction velocities, as measured at 12 °C. The temperature dependence of the conduction velocity was bimodal, changing its slope at about 16 °C. The Q ₁₀ above 16 °C was 1.12–1.49, while below 16 °C it was 1.82–2.16. Irreversible deterioration of the nerve was observed at temperatures around 19–27 °C. A comparison with data previously obtained from Mediterranean fishes indicates that Arctic fishes have similar temperature sensitivity of nerve conduction and a slight vertical displacement on the conduction velocity-temperature curves, which is insufficient to compensate the decrease of the conduction velocity at their physiological temperature, the conduction velocity of Arctic fishes being about one-half of that of temperate fishes. This suggests that this neurophysiological function is not fully cold-adapted in these Arctic fish species. Accepted: 3 June 2000     

Last days in the old radiation laboratory (ORL), Berkeley,California, 1954

Govindjee, the founding editor of the Historical Corner of Photosynthesis Research, invited me 3 years ago to tell the story of why I left Melvin Calvin’s laboratory in the mid 1950s long before the 1961 Nobel Prize in Chemistry was awarded to Calvin for the path of carbon in photosynthesis. I have already written my scientific perspective on this topic (see Benson (Photosynth Res 73:29–49, 2002); also see Bassham (Photosynth Res 76:35–52, 2003) as he was also a major player in this research). Here, I present my recollections of my last days in the old radiation laboratory (ORL) at Berkeley, California. References have been added by Govindjee for the benefit of the readers.     

Limits of a multi-patch SIS epidemic model

 We start from a stochastic SIS model for the spread of epidemics among a population partitioned into M sites, each containing N individuals; epidemic spread occurs through within-site (`local') contacts and global contacts. We analyse the limit behaviour of the system as M and N increase to ∞. Two limit procedures are considered, according to the order in which M and N go to ∞; independently of the order, the limiting distribution of infected individuals across sites is a probability measure, whose evolution in time is governed by the weak form of a PDE. Existence and uniqueness of the solutions to this problem is shown. Finally, it is shown that the infected distribution converges, as time goes to infinity, to a Dirac measure at the value x ^* , the equilibrium of a single-patch SIS model with contact rate equal to the sum of local and global contacts. Received: 18 July 2001 / Revised version: 16 March 2002 / Published online: 26 September 2002 Mathematics Subject Classification (2000): 92D30, 60F99 Key words or phrases: SIS epidemic – Metapopulation – Markov population processes – Weak convergence of measures     

Siphonogobius nue, a new genus and species of gobiid fish from japan

A new genus and species of gobiid fish,Siphonogobius nue, based on 15 specimens, is described from temperate Pacific coasts of Japan. It is unique amongst gobioids in having a simple tube-like infraorbital canal extending below the eye and the oculoscapular canal between pores A' and L' without openings, except for the terminal pores and pore D. Although well-developed infraorbital canals occur in two other gobioid genera, the rhyacichthyidRhyacichthys and the gobiidLophiogobius, such are distinct from that ofSiphonogobius in having several branches and openings. Furthermore, the new taxon is distinguished from all other gobioids by the following combination of characters: first dorsal-fin spines 7–9 (usually 8); pectoral-fin rays 24–26, the upper 7–9 rays free from the fin membrane; pelvic frenum thick, robust and slightly emarginate posteriorly; scales small and cycloid, 87–96 in longitudinal series; vertebrae 14–15+19–20=33–34 (usually 14+20=34); P-V usually 3/I II II I I I 0/11; anal-fin pterygiophores anterior to the first haemal spine 3–4 (usually 3); a row of short fleshy flaps on the ventral surface of the head, extending from the lower edge of the preopercle to the chin; anterior nostril with a minute skin flap. Axial skeletal features indicated thatSiphonogobius is closely related to a group which includesAcanthogobius and its relatives.     

Tolerance of nonindigenous cichlid fishes (<Emphasis Type="Italic">Cichlasoma urophthalmus</Emphasis>, <Emphasis Type="Italic">Hemichromis letourneuxi</Emphasis>) to low temperature: laboratory and field experiments in south Florida

The cold tolerance of two non-native cichlids (Hemichromis letourneuxi and Cichlasoma urophthalmus) that are established in south Florida was tested in the field and laboratory. In the laboratory, fishes were acclimated to two temperatures (24 and 28°C), and three salinities (0, 10, and 35 ppt). Two endpoints were identified: loss of equilibrium (11.5–13.7°C for C. urophthalmus; 10.8–12.5°C for H. letourneuxi), and death (9.5–11.1°C for C. urophthalmus; 9.1–13.3°C for H. letourneuxi). In the field, fishes were caged in several aquatic habitats during two winter cold snaps. Temperatures were lowest (4.0°C) in the shallow marsh, where no fish survived, and warmest in canals and solution-holes. Canals and ditches as shallow as 50 cm provided thermal refuges for these tropical fishes. Because of the effect on survival of different habitat types, simple predictions of ultimate geographic expansion by non-native fishes using latitude and thermal isoclines are insufficient for freshwater fishes.     

On the dynamics of discrete food chains: low- and high-frequency behavior and optimality of chaos

 In this paper we derive and analyze a discrete version of Rosenzweig's (Am. Nat. 1973) food-chain model. We provide substantial analytical and numerical evidence for the general dynamical patterns of food chains predicted by De Feo and Rinaldi (Am. Nat. 1997) remaining largely unaffected by this discretization. Our theoretical analysis gives rise to a classification of the parameter space into various regions describing distinct governing dynamical behaviors. Predator abundance has a local optimum at the edge of chaos. Received: 13 August 1999 / Revised version: 12 March 2002 / Published online: 17 October 2002 Mathematics Subject Classification (1991): 92D40 Keywords or phrases: Discrete food-chain – Discrete Hopf (Neimark-Sacker) bifurcation – Pulsewise birth processes – Mean yield maximization – Nicholson-Bailey model     

A new silverside, <Emphasis Type="Italic">Atherinomorus aetholepis</Emphasis> sp. nov., from the West Pacific (Atheriniformes: Atherinidae)

Atherinomorus aetholepis sp. nov. is described from the holotype and 51 paratypes, 44–72 mm in standard length, collected from Indonesian and Philippine waters. The species is similar to other congeners in general body appearance, especially A. duodecimalis and A. regina, in having a slender body, a tubercle on the posterior end of the dentary, and a narrow midlateral band, but clearly differing from them in having a long spatular outgrowth on the posterior margins of most of the predorsal and interdorsal scales. Additionally, the species differs from A. duodecimalis in having a more slender body [body depth 17–22 (mean 19) % SL vs. 19–25 (mean 22) % SL], more midlateral scales [37–40 (mean 38.4) vs. 35–38 (mean 36.6)], more total vertebrae [38–42 (mean 39.9) vs. 36–40 (mean 38.0)], and fewer lower gill rakers [18–22 (mean 20.2) vs. 20–25 (mean 22.3)], and from A. regina in having more anal fin soft rays (12–14 vs. 9–10). Electronic supplementary material to this article is available at and accessible to authorized users. Received: October 22, 2001 / Revised: March 14, 2002 / Accepted: March 26, 2002 An erratum to this article is available at .     

Transpiration and whole-tree conductance in ponderosa pine trees of different heights

Changes in leaf physiology with tree age and size could alter forest growth, water yield, and carbon fluxes. We measured tree water flux (Q) for 14 ponderosa pine trees in two size classes (12 m tall and ∼40 years old, and 36 m tall and ∼ 290 years old) to determine if transpiration (E) and whole-tree conductance (g _t) differed between the two sizes of trees. For both size classes, E was approximately equal to Q measured 2 m above the ground: Q was most highly correlated with current, not lagged, water vapor pressure deficit, and night Q was <12% of total daily flux. E for days 165–195 and 240–260 averaged 0.97 mmol m^–2 (leaf area, projected) s^–1 for the 12-m trees and 0.57 mmol m^–2 (leaf area) s^–1 for the 36-m trees. When photosynthetically active radiation (I _P) exceeded the light saturation for photosynthesis in ponderosa pine (900 μmol m^–2 (ground) s^–1), differences in E were more pronounced: 2.4 mmol m^–2 (leaf area) s^–1 for the 12-m trees and 1.2 mmol m^–2 s^–1 for the 36-m trees, yielding g _t of 140 mmol m^–2 (leaf area) s^–1 for the 12-m trees and 72 mmol m^–2 s^–1 for the 36-m trees. Extrapolated to forests with leaf area index =1, the 36-m trees would transpire 117 mm between 1 June and 31 August compared to 170 mm for the 12-m trees, a difference of 15% of average annual precipitation. Lower g _t in the taller trees also likely lowers photosynthesis during the growing season. Received: 19 April 1999 / Accepted: 23 March 2000     

<Emphasis Type="Italic">Acropoma argentistigma</Emphasis>, a new species from the Andaman Sea,off southern Thailand (Perciformes: Acropomatidae)

 A new acropomatid fish, Acropoma argentistigma, is described on the basis of six specimens (59.0–107.5 mm in standard length) from the Andaman Sea, off southern Thailand (Phuket Island). The new species is distinguished from all other congeners by the combination of the following characters: a short U-shaped luminous gland, 16–18 gill rakers, anus situated about midway along depressed pelvic fin, proximal radial of first anal fin pterygiophore with a trough, a single row of well-developed conical teeth on the lower jaw, and head length 40.0–41.1% of standard length. Received: April 17, 2001 / Revised: April 15, 2002 / Accepted: May 7, 2002     

Redescription of <Emphasis Type="Italic">Bregmaceros mcclellandi</Emphasis> Thompson, 1840 (Gadiformes: Bregmacerotidae)

 This study redescribes Bregmaceros mcclellandi Thompson, 1840, based on one specimen (74.4 mm SL) from the Bay of Bengal and 66 specimens (30.0–84.7 mm SL) from Mumbai (Bombay), India, because the type specimens have apparently been lost. The present specimens are characterized by having black dorsal, pectoral, and caudal fins and show the following morphology: caudal fin slightly forked; body chromatophores present mainly at the dorsal part; no scales on cheek; vertebrae 52–55 (13–15 + 38–41); dorsal rays 52–59; anal rays 54–60; pectoral rays 18–20; caudal rays 27–31 (principal rays 14); transverse scales 14–15. In the 66 Mumbai specimens, it was confirmed that the distinctive black fin pigmentation developed sequentially with growth, with complete pigmentation first on the anterior lobe of the dorsal fin, then simultaneously on the posterior lobe of the dorsal fin, the caudal fin, and the pectoral fin, and last, on the anal fin. This species is known only from the Arabian Sea, Bay of Bengal, and Gulf of Thailand. A review of 16 nominal Bregmaceros species indicates that, besides B. mcclellandi, the distinctive dark fin pigmentation is found in B. atripinnis (Tickell), B. atlanticus Goode and Bean, B. japonicus Tanaka, and B. lanceolatus Shen. B. atripinnis is considered a junior synonym of B. mcclellandi, and the others are clearly distinct from B. mcclellandi. Comments are made on some of the characters to more fully characterize the species and for reference in future revisionary and phylogenetic studies. Received: June 17, 2002 / Revised: December 2, 2002 / Accepted: December 24, 2002     

Comparative Feeding Ecology of Two Sympatric Greenling Species, <Emphasis Type="Italic">Hexagrammos otakii</Emphasis> and <Emphasis Type="Italic">Hexagrammos agrammus</Emphasis> in Eelgrass <Emphasis Type="Italic">Zostera marina</Emphasis> Beds

Synopsis Feeding ecology was compared between sympatric greenling species, Hexagrammos otakii and H. agrammus in the eelgrass beds in Jindong Bay, Korea, from January to December. These two species had similar diets composed of crustaceans, polychaetes, gastropods and fishes; both species consumed primarily crustaceans throughout study periods. H. otakii, however, fed a greater proportion of polychaetes and fishes than H. agrammus. H. agrammus had a greater proportion of gastropods in their diets. The diet of both species underwent size-related changes; smaller individuals of H. otakii and H. agrammus consumed amphipods (gammarid amphipods and caprellid amphipods), while larger individuals of H. otakii ate polychaetes and fishes and those of H. agrammus fed mainly on gastropods and crabs. The diet of H. otakii underwent seasonal changes; H. otakii consumed mainly polychaetes and fishes during January and February 2002 but amphipods during March and May 2002. H. agrammus, however, ate mainly gastropods and crabs all seasons. H. otakii underwent also a significant diel changes that could be related to difference of prey availability. Thus the nocturnal emergence of gammarid amphipods, polychaetes and fishes explained their greater consumption by H. otakii. Dietary breadth of both species was lower in the smallest individuals (<5 cm SL) and in March and April 2002. This was due to the disproportionate dry mass attributable to the consumption of amphipods by both H. otakii and H. agrammus. Dietary overlap of both species was relatively moderate to high, in particular in <9.9 cm SL (0.62 – 0.71) from May to July 2002 (0.63 – 0.71). This is coincident with higher abundances of crabs, caridean shrimps and polychaetes in the study area, and it was assumed that these prey species were not limited resources. Higher dietary overlap was correlated with an abundance of a shared resource and did not indicate the interspecific competition between H. otakii and H. agrammus.     

On spreading speeds and traveling waves for growth and migration models in a periodic habitat

 It is shown that the methods previously used by the author [Wei82] and by R. Lui [Lui89] to obtain asymptotic spreading results and sometimes the existence of traveling waves for a discrete-time recursion with a translation invariant order preserving operator can be extended to a recursion with a periodic order preserving operator. The operator can be taken to be the time-one map of a continuous time reaction-diffusion model, or it can be a more general model of time evolution in population genetics or population ecology in a periodic habitat. Methods of estimating the speeds of spreading in various directions will also be presented. Received: 12 July 2001 / Revised version: 19 July 2002 / Published online: 17 October 2002 Mathematics Subject Classification (2000): 92D40, 92D25, 35K55, 35K57, 35B40 Keywords or phrases: Periodic – Spreading speed – Traveling wave     

Year class coexistence or competitive exclusion for strict biennials?

 We consider a discrete time model of semelparous biennial population dynamics. Interactions between individuals are modelled with the aid of an ``environmental' variable I. The impact on and the sensitivity to the environmental condition is age specific. The main result is that competitive exclusion between the year classes is possible as is their coexistence. For moderate values of the basic reproduction ratio R ₀ there is a strict dichotomy: depending on the other parameters we either find competitive exclusion or coexistence. We characterize rather precisely the patterns of age specific impact and sensitivity that lead to either of these outcomes. Received: 13 July 2001 / Revised version: 26 June 2002 / Published online: 19 November 2002 Key words or phrases: Competitive exclusion – Semelparous species – Periodical insects     

Effects of mating rates on oviposition,sex ratio and longevity in a predatory mite <Emphasis Type="Italic">Neoseiulus cucumeris</Emphasis> (Acari: Phytoseiidae)

Two aspects of mating effects on the fecundity, sex ratio and longevity of Neoseiulus cucumeris (Acari: Phytoseiidae) were examined in laboratory experiments: (1) females mated by one, two or three different males (unmated and 3 days old) at 5-day intervals, and (2) females mated by males with different age/mating status (number of females mated previously by the male). Females allowed to mate with a second or third male at 5-day intervals produced 39 eggs on average, but those mated with a single male produced 28 eggs on average. Matings with additional males 5 or 10 days after the first male increased the duration of the oviposition period of these females by 5–7 days and at the same time reduced the post-oviposition period by about 10 days. Overall, females with additional matings by one or two different males at 5-day intervals survived a few days shorter than females without additional males. Mating with a different female each day, a male of N. cucumeris could mate with 5–8 females, which produced a total of 85–116 eggs: females mated with a male during days 1 and 2 in its adulthood and with a male of the last 2 days of life (days 7 and 8) produced about half as many eggs as females mated with a male during 3–6 days of its adulthood. Females mated with males that are too young or too old had a shorter oviposition period and a longer post-oviposition period and longevity than females mated with middle-aged males. In both experiments, rates of oviposition remained similar in females with high or low fecundity. This indicates that in both cases, the increased fecundity is due to the extension of the oviposition period through additional sperm supplied by the second male and or third male (in experiment 1) or more sperm by males not too young nor too old (experiment 2).     

Inducible heat tolerance in Antarctic notothenioid fishes

Significant increases in heat tolerance (time of survival at 14°C) were observed for some, but not all, species of notothenioid fishes collected from McMurdo Sound, Antarctica (77°51′S) following acclimation to 4°C. The increase in thermal tolerance was rapid in Trematomus bernacchii, developing within 1–2 days of acclimation to 4°C. Long-term (6–8 weeks) acclimation to 4°C led to greater heat tolerance in Trematomus pennellii than in T. bernacchii. Unlike its demersal congeners, the cryopelagic notothenioid Pagothenia borchgrevinki did not increase heat tolerance during warm acclimation. A deep-living zoarcid fish, Lycodichthys dearborni, also failed to increase heat tolerance, but survived significantly (> threefold) longer at 14°C than the notothenioids.     

Mesopristes iravi, a new terapontid fish (Perciformes: Terapontidae) from rivers of Iriomote Island, the Ryukyu Islands

 A new terapontid fish, Mesopristes iravi, is described based on 13 specimens collected on Iriomote Island, the Ryukyu Islands, Japan. This species closely resembles M. argenteus (Cuvier in Cuvier and Valenciennes, 1829) in having dark stripes on the body, but differs from that species in retaining the stripes even in adults (vs. stripes disappearing ontogenetically in the latter species), having the median stripe passing through the eye interrupted on the postorbital region (vs. continuous when the stripe present), a shorter fifth (longest) dorsal spine (14.6–19.7% SL vs. 18.0–22.2% SL), and a longer postorbital length (40.0–43.0% HL vs. 37.8–40.7% HL). Mesopristes iravi has been confused with M. argenteus in previous reports, and on the basis of the literature it may extend from the Ryukyu Islands, Japan, southward to Borneo, Indonesia, and New Guinea. Received: August 6, 2001 / Revised: February 24, 2002 / Accepted: March 7, 2002     

Contributions of stable-isotope data to elucidating food webs of Mediterranean rocky littoral fishes

The food webs of rocky infra-littoral ecosystems in the Mediterranean have been little studied. In this investigation stable isotopes and dietary data were compared in an attempt to describe features of the food webs concerned. δ¹³C and δ¹⁵N were determined for plants, invertebrates and fishes from the Bay of Calvi, Corsica. Dietary data were derived from the literature. δ¹³C of plants ranged from –8.59‰ to –33.74‰, of benthic invertebrates from –17.0‰ to –20.52‰, of planktonic invertebrates from –20.08‰ to –22.34‰ and of fishes from –16.27‰ to –19.59‰. δ¹⁵N was generally greater at higher trophic levels. δ¹⁵N of plants was 0.95–2.92‰, of benthic invertebrates 1.69–6.54‰, of planktonic invertebrates 3.51–6.82‰ and of fishes 4.63–9.77‰. ¹³C enrichment tended to be associated with benthic food chains and ¹³C depletion with planktonic chains. Stable-isotope data suggested more varied diets for many species than implied by gut-contents data. Omnivory and trophic plasticity were widespread, and many consumers fed lower down the food chain than previous studies had suggested. Both stable-isotope and gut-contents analysis resolved differences between fishes feeding on planktonic and benthic prey and indicated that the herbivorous fish Sarpa salpa fed on a diet substantially different from that of other fishes. Zooplankton were important in the diets of several consumers (both primary and secondary), as was plankton derived detritus. One species of fish previously identified as planktivorous was shown to feed largely on benthic organisms, whilst several species of benthic invertebrates may feed on plankton-derived detritus. Although herbivores seemed to obtain most of their C from macroalgae, δ¹⁵N data suggested that many of these animals supplemented their intake of N, although gut-contents analysis did not provide evidence for such uptake. The isotopic data have elucidated several features of the food web which we would not otherwise have detected. Received: 26 April 1999 / Accepted: 24 September 1999     

Sperm Nuclear Basic Proteins (SNBPs) of Agnathans and Chondrichthyans: Variability and Evolution of Sperm Proteins in Fish

We have characterized for the first time SNBPs from the hagfish Eptatratus stouti (Myxini) and the lamprey Lampetra tridentatus (Cephalaspidomorphi) and have found that histones are the major protein components of the sperm of these agnathans. We have also conducted a systematic analysis of SNBPs from different groups of chondrichthyan fishes, including the skate Raja rhina and seven species of sharks. Together with our previous data showing the sporadic nature of SNBP evolution in bony fish (Saperas, N., Ausio, J., Lloris, D. and Chiva, M. [1994] J. Mol. Evol. 39: 282–295), the present study provides a unique insight into the overall evolutionary complexity and variability of the nuclear sperm proteins of fishes. It would appear that despite the discontinuous evolution of these proteins, the macroevolutionary pattern of histone (H type) → protamine-like (PL type) → protamine (P type) has been conserved in fish evolution, as it has in the evolution of other Deuterostomes. Received: 11 June 1996 / Accepted: 6 August 1996