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Theischinger, G., Gassmann, D., Richards, S. J. (2015): Macrocnemis gracilis, a new genus and species of Idiocnemidinae (Zygoptera: Platycnemididae) from Papua New Guinea. Zootaxa 3990 (3): 429-436, DOI: http://dx.doi.org/10.11646/zootaxa.3990.3.7

Macrocnemis gracilis sp. nov. Figs 1–16 Holotype. ♂ (SAMA 07-001406): Papua New Guinea, Hindenburg Range, Bilbilokabip (5.1203 o S, 141.2512 o E, 1770 m asl), 14 -II- 2013, S. J. Richards leg. Paratypes. 3 ♂ (SAMA 07-001407, RMNH, ZFMK ODO 20150001), same locality and collector, 12–17 -II- 2013, 2♀ (SAMA 07-001408, RMNH) same details as holotype, collected 12 and 22 -II- 2013, respectively. Etymology. Gracilis (= Latin for slender) owing to the very long and slender abdomen of the male. Description of the holotype male. Head. Labium with median incision U-shaped, largely yellow; mandibles basally pale green, otherwise brown to black; labrum dull pale green, basally very narrowly and in dorsal half along midline broadly black; anteclypeus black; genae, postclypeus and anterior frons up to antennal bases pale bluish green, a narrow black line separating postclypeus and frons; top of frons, pedicel, vertex and postocular lobes largely black, a spot each side of median ocellus and anterior to each lateral ocellus and a narrow occipital line pale brownish yellow; small postocular spots pale green; postgenae in preserved specimen largely dull yellow. Thorax. Pronotum medially more or less broadly black, laterally yellow; posterior lobe upright, more or less rectangular with top corners drawn out into tongue-like lobes; episternum about half black and half yellow; epimeron largely black, yellow only along ventral margin. Synthorax black with wedge-shaped antehumeral patch, parts of dorsal half of mesepimeron and more than anterior half of metanepisternum, almost all of metepimeron and metapostepimeron, two anterior spots and posteroventral corner of mesokatepisternum and only posteroventral tip of metakatepisternum pale green to dull yellow; metapostcoxae and poststernum dull yellow; coxae and trochanters largely dull yellow, femora largely dull to greyish and brownish yellow lined with blackish grey, foretibia greyish black, meso- and metatibia with inner face greyish black, otherwise pale greyish to dark yellowish brown; all spines (6 doubles and 1 single on fore- and mesotibia, 7 doubles and 1 single on metatibia) and tarsi black; claws greyish to yellowish brown with small secondary tooth. Wings. Membrane hyaline; venation blackish brown. Wing length:greatest width ratio 6.0– 6.3; wing tips very weakly crenulated from 5 cells beyond pterostigma to R 4 meeting wing margin; 16–17 / 14 postnodals; pterostigma about 1 ½ times as long as wide, parallelogram-shaped, greyish brown; overlying generally 1 cell. Other characters as given under Macrocnemis gen. nov. Abdomen. Largely black with predominantly pale brownish yellow markings including in S 1 approximately apical half and ventral margin, in S 2 much of ventral margin; in each of S 3–7 an ill-defined basal ventrolateral patch covering 1 / 6 or less and an even less well-defined ventrolateral patch covering more than subapical 1 / 6 of segment length, in S 8 much of sides, in S 9 apical half and in S 10 almost all of it. S 2 in addition with a well-defined yellowish-green dorso-median patch over approximately medial third of its length. Anal appendages pale brownish yellow with cerci boomerang-shaped with dorsal bump beyond mid-length and bifid apex shaped similar to a boxing glove and paraprocts slightly longer than cerci, from wide and deep at base tapering into slightly curved/ sinuous slender rods (Figs 8–10). Ligula. Ligula in ventral view narrow, elongate (Fig. 11). Terminal segment with apical lobes medium-sized, lanceolate (Fig. 12), slightly twisted in posterior lateral view (Fig. 14). Limbus membranosus short, covered with spine- or setae-like processes (Fig. 13). Measurements. Hw 30.0 mm; abdomen including anal appendages 46.2 mm. Variability. All paratypes agree well with the description of the holotype. The range of the species’ postnodals is 16–17 / 13–14, of hindwing length 30.0– 32.9 mm, of abdomen length (including appendages) 46.2 –49.0 mm. Female. Head. Labium dirty to bright yellow, lateral (movable) hook black, end-hook yellow; mandibles dirtyyellow, distal parts brown to black; labrum obscure brown-black to olive-green, a weak light-brown marking to either side of the medio-basal oval black depression; anteclypeus dark brown; postclypeus dirty brown-black to yellowish-green; frons covered by a yellowish-green stripe, laterally extending up to eye margins, dorsally up to antennal scapi, at that level somewhat intermingled with black; antennae medium to dark brown; vertex and occiput dark greenish-brown to black, intermingled with rusty areas, the latter colour concentrated around and between ocelli; a diffuse dark spot attached to inner side of posterior ocellus, respectively; area between ocelli and occipital ridge conspicuously deep black, either entirely so or marked by a distinct black line. Rear and underside of head yellowish-white. Thorax. Prothorax with both halves of median lobe distinctly bulgy in lateral view; posterior pronotal lobe not upright, a little more than half length of median lobe, simpler shaped than in male and smoothly rounded, with sublateral areas not protruded but slightly emarginate (almost trapezoid-shaped in dorsolateral view), lateral edges distinctly protruded but rounded. Colour of prothorax, legs and synthorax similar to male but generally paler and of less contrast. Synthorax with black markings less extensive than in male, that on upperside of synthorax restricted to cover dorsal carina. Underside of synthorax yellowish-white. Wings. 15–16 / 13 postnodals; length:greatest width ratio 6.2. Abdomen. Colour similar to male but S 8 to 9 with weaker diffuse yellow-white markings, roughly covering lateral areas of posterior halves of segments and entire ventrolateral area of S 8. S 10 dark brown, laterally with a diffuse medium brown area at either side. Cerci, valvae and styli largely deep black, but upper part of valvae, visible part of ovipositor and distal fifths of styli light brown. Rear of abdomen bright yellow, framed by black. Measurements. Hw 32.5 mm; abdomen including styli 44.5–45.5 mm. Diagnosis. The largest species of idiocnemidine Platycnemididae from New Guinea (with wings at least 30 mm, abdomen almost 50 mm); three cells between quadrilateral and subnodus and distal margin slightly but distinctly crenulated in both wings; cerci and paraprocts of male subequal in length. Habitat. The type locality, Bilbilokabip, is a small hamlet used by local landowners as a temporary shelter when hunting and gardening in the upper Kam Valley. The small clearing containing three huts is surrounded by extremely wet, moss-covered mid-montane rainforest where Macrocnemis gracilis perched on low vegetation overhanging or adjacent to small (1–2 m wide; Fig. 15) clear and heavily shaded streams. It was also encountered, but was less common, along a wider (5–10 m; Fig. 16) torrential stream that flooded regularly after heavy rain during the survey period. The streams where M. gracilis were encountered all had extensive canopy cover and dense riparian vegetation (Figs 15, 16); the species was not encountered along streams where canopy cover had been opened during establishment of gardens despite extensive searches in more disturbed habitats.

Macrocnemis gen. nov. Etymology. The generic name is a composite of macro, meaning large, and cnemis, meaning tibia (= shin), the basis of the name for several genera supposed to be close allies of the new genus. Diagnostic characters. Very large, long-bodied, narrow-winged damselfly, the male black with pale yellowish green thoracic and largely pale brownish-yellow abdominal markings, including two sets of lateral patches each on segments 3���7. Antennae in both sexes with relative length of first and second joints about 1: 2. Posterior lobe of male pronotum upright, more or less rectangular with the top corners drawn out into tongue-like lobes. Female prothorax simple, posterior lobe laterally protruded. Ac located approximately mid-way between levels of Ax 1 and Ax 2. Quadrilateral widening distally, that of Fw with basal side approximately 1 / 2 as long as costal and distal side and 1 / 3 as long as posterior side, that of Hw with basal side 1 / 4 ��� 1 / 3 as long as costal side, approximately 2 / 3 as long as distal side and 1 / 5 as long as posterior side. Three cells between distal end of quadrilateral and level of subnodus. R 4 arising a little before subnodus, IR 3 at subnodus. Majority of cells in distal half of wings (between R 2 and R 4) squarish. Distal margin of wings weakly crenulated. Abdomen with S 9 and S 10 not significantly widened; markings largely pale brownish yellow and including two sets of lateral patches each on segments 3���7. Male with cerci almost as long as, and stouter than, the simple slender paraprocts. Ligula simple, with a pair of medium-sized apical lobes. Ovipositor valvae reaching slightly beyond end of abdomen, not surpassing cerci., Published as part of Theischinger, G., Gassmann, D. & Richards, S. J., 2015, Macrocnemis gracilis, a new genus and species of Idiocnemidinae (Zygoptera: Platycnemididae) from Papua New Guinea, pp. 429-436 in Zootaxa 3990 (3) on page 430, DOI: 10.11646/zootaxa.3990.3.7, http://zenodo.org/record/245965

Asthenocnemis linnaei spec. nov. is described from the Philippine island of Dumaran in the northeastern Palawan subregion. Notes on the taxonomic history of the genus Asthenocnemis are provided.

Idiocnemis patriciae spec. nov. is described from lowland rainforests of the Dark-End Lumber and Lakekamu regions in Gulf Province, Papua New Guinea. Biogeographically, the new species is near-endemic to the Papuan Gulf Coastal Lowlands area of endemism. Notes on the habitat of the new species and on a female specimen from the Lakekamu Basin tentatively assigned to it, are included. The distributions of I. australis Gassmann, I. chloropleura Lieft inck and I. kimminsi Lieft inck are updated. I. chloropleura is recorded from Yapen island for the first time. A revised key to the males of the Idiocnemis inornata species-group is provided.

The excitation energies and spins of the levels in the yrast superdeformed band of $^{191}$Hg have been determined from two single-step $\gamma$ transitions and the quasi-continuum spectrum connecting the superdeformed and normal-deformed states. The results are compared with those from theoretical mean-field calculations with different interactions. A discussion of pairing in superdeformed states is also included., Comment: 8 pages, 11 figures

Excited states in the second minimum of Pu-240 were populated by the U-238(alpha, 2n) reaction at E-alpha=25 MeV. Conversion electrons from electromagnetic transitions preceding the fission of the 3.7 ns Pu-240f Shape isomer have been measured. In a combined analysis of e(-) and high resolution gamma -ray spectroscopy data previously established octupole bands could be studied in more detail. In order to study higher lying states in the second and third minimum the Pu-239(d,pf)Pu-240, and the U-233(d,pf)U-234 reactions have been studied with high energy resolution. The observed fission resonances were described as members of rotational bands with rotational parameters characteristic to super- and hyperdeformed nuclear shapes. The level density of the most strongly excited states has been compared to the prediction of the back-shifted Fermi-gas formula and the energy of the ground state in third minimum has been estimated for the first time in U-234. The fission fragment mass distribution of the hyperdeformed states in U-236 has also been measured. The width of the mass distribution, coincident with the hyperdeformed bands, is significantly smaller than the ones obtained in coincidence with background regions below and above the resonances, which suggests a pear-shaped di-nuclear configuration of U-236 in the third well of the potential barrier.

The intermediate structure of the fission resonances has been observed in Pu-240. A resonance structure found around the excitation energy of 4.5 MeV was interpreted as a group of K-pi = 0(+) superdeformed rotational bands. The moments of inertia and level density distributions were also deduced for the individually observed band-heads.

Eight species of the Papuan genus Idiocnemis Selys, 1878, sharing common traits in ligula structure and colour pattern, referred to here as the Idiocnemis bidentata-group, are redescribed or newly described. Taxonomy and distribution are updated and one new taxon, Idiocnemis polhemi spec. nov., is described from South-East New Guinea.

The U-233(d,pf)U-234 reaction has been studied with high energy resolution. The observed fission resonances in the excitation energy range of 4.75 less than or equal to E* less than or equal to 5.40 MeV were described as members of rotational bands with rotational parameters characteristic to the hyperdeformed nuclear shape ((h) over bar(2)/2 theta = 2.1 +/- 0.2 keV). Information on the K values of the bands has been obtained from fission fragment angular distribution measurements. The level density of the most strongly excited J = 3 states has been compared to the prediction of the back-shifted Fermi-gas formula and the energy of the ground state in the third minimum has been estimated to be E-III = 3.1 +/- 0.4 MeV

The decay-out spectrum of the superdeformed yrast band in 192Hg comprises a quasicontinuum, from which about 50 weak discrete transitions of energy between 1 and 3.2 MeV are resolved. The fluctuations of the one-dimensional quasicontinuum spectrum are studied with the fluctuation analysis method, which shows that of the order of a few thousand different transitions are available in the first step of the decay-out cascades. The experimental effective number of transitions is compared to schematic theoretical calculations.

A new superdeformed band has been identified in Hg191 bringing the total number of bands observed in this nucleus to four. The new band has properties similar to those of a superdeformed band reported recently in Hg193. Both bands are believed to be built on the unfavored signature of the j15/2 intruder configuration. Comparisons between the data and cranked Woods-Saxon calculations highlight the strengths and weaknesses of theory in describing high-N orbitals at large deformation.

A superdeformed band has been found in the Dy154 (N=88) nucleus. The dynamic moment of inertia is identical to that of the yrast superdeformed band of Dy152 and the transition energies are similar to those of an excited superdeformed band in Dy153. It is proposed that the two valence neutrons above the N=86 shell gap occupy the deformation-driving [514]9/2 orbital.

Statistical γ-decay spectra from excited nuclear states are calculated. The spectra reflect the perturbation of the level density by pair correlations and, hence, the stepwise weakening of the pair correlations with increasing quasiparticle number. The level density is obtained by counting many-quasiparticle states from a self-consistent BCS calculation or from a diagonalization of particle number-projected states. The calculated spectra resemble measured spectra from the decay out of superdeformed bands, but have only ∼70% of the measured intensity.