A Study on the Identity of Bracon hebetor Say and Bracon brevicornis Wesmael (Hymenoptera: Braconidae)

1956 ◽  
Vol 47 (1) ◽  
pp. 183-191 ◽  
Author(s):  
M. Puttarudriah ◽  
G. P. Channa Basavanna

Literature, mainly Indian, pertaining to the recorded hosts of Bracon hebetor Say and B. brevicornis Wesm., and on the taxonomy of the two species, has been reviewed. Observations on different morphological characters, including the male and female genitalia, which have been used in establishing the identity of the two species, have been made. A large number of B. hebetor specimens reared in Bangalore on Corcyra cephalonica (Stnt.), Ephestia cautella (Wlk.), Adisura atkinsoni Moore and those collected in food-grain godowns, and of B. brevicornis reared on C. cephalonica and E. cautella in Bangalore, on Nephantis serinopa Meyr. from Coimbatore (South India), on Pyrausta nubilalis (Hb.) from Canada and on cotton bollworms (?) from Delhi (North India), have been examined.Differences in colour, relative proportions of antennal joints and punctation on the abdomen have been found to be variable and as such are not to be depended upon for distinguishing the two species. The number of antennal joints which has hitherto been considered to be the decisive character by which the two species may be separated is also not reliable as there is a wide range of variation even in the progeny of a single pair of parents. Above all, the fact that the two species interbreed and give rise to fertile offspring, which also show a fairly wide range of variation in the number of antennal joints, proves that the two are identical, and there is no ground to treat them as two distinct species, at least so far as the Indian specimens are concerned, for which Bracon hebetor Say is the valid name.

1997 ◽  
Vol 71 (4) ◽  
pp. 564-577 ◽  
Author(s):  
D. K. Pandey ◽  
B. Lathuiliere

Epistreptophyllum cornutiformis Gregory, 1900, is the name assigned to a Middle Jurassic population of scleractinian corals from Kachchh, western India. Measurements of ten variables from 84 specimens of this population have been statistically examined by means of univariate and multivariate analyses. A wide range of variation in corallum shape, septal perforation, lateral septal surface ornamentation, nature of the endotheca, and that of the columella is observed. The great majority of specimens are solitary. The wide range of gradational variation observed in this population corresponds to and includes the morphological characters described for various scleractinian genera such as Protethmos Gregory, Metethmos Gregory, Frechia Gregory, and Epistreptophyllum Milaschewitsch. The assignment of these genera to this later senior synonym genus is supported by the description of a well-preserved topotype from Nattheim. The ornamentation of the septa in Epistreptophyllum is detailed and distances it from typical pennular corals.


1994 ◽  
Vol 29 (3) ◽  
pp. 207-209 ◽  
Author(s):  
H. Puzicha

Effluents from point sources (industries, communities) and diffuse inputs introduce pollutants into the water of the river Rhine and cause a basic contaminant load. The aim is to establish a biological warning system to detect increased toxicity in addition to the already existing chemical-physical monitoring system. To cover a wide range of biocides, continuous working biotests at different trophic levels (bacteria, algae, mussels, water fleas, fishes) have been developed and proved. These are checked out for sensitivity against toxicants, reaction time, validity of data and practical handling under field conditions at the river. Test-specific appropriate methods are found to differentiate between the normal range of variation and true alarm signals.


Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 518
Author(s):  
Bronwyn Egan ◽  
Zwannda Nethavhani ◽  
Barbara van Asch

Macrotermes termites play important ecological roles and are consumed by many communities as a delicacy and dietary complement throughout Africa. However, lack of reliable morphological characters has hampered studies of Macrotermes diversity in a wide range of scientific fields including ecology, phylogenetics and food science. In order to place our preliminary assessment of the diversity of Macrotermes in South Africa in context, we analysed a comprehensive dataset of COI sequences for African species including new and publicly available data. Phylogenetic reconstruction and estimates of genetic divergence showed a high level of incongruity between species names and genetic groups, as well as several instances of cryptic diversity. We identified three main clades and 17 genetic groups in the dataset. We propose that this structure be used as a background for future surveys of Macrotermes diversity in Africa, thus mitigating the negative impact of the present taxonomic uncertainties in the genus. The new specimens collected in Limpopo fell into four distinct genetic groups, suggesting that the region harbours remarkable Macrotermes diversity relative to other African regions surveyed in previous studies. This work shows that African Macrotermes have been understudied across the continent, and that the genus contains cryptic diversity undetectable by classic taxonomy. Furthermore, these results may inform future taxonomic revisions in Macrotermes, thus contributing to advances in termitology.


Parasitology ◽  
1915 ◽  
Vol 8 (1) ◽  
pp. 11-16 ◽  
Author(s):  
L. E. Robinson

Variability in the size and, in a lesser degree, the taxonomic features of male ticks, has arrested the attention of all who have had occasion to examine moderately large numbers of examples of the same species. In the case of the female tick, this variability, though doubtless coextensive with that of the male, is more or less obscured by the wide range of variation in size, depending upon the degree of engorgement; and, also, by the fact that in the female tick the taxonomic characters are, as a rule, less pronounced. The present note is only concerned with variability in the size of the male.


1957 ◽  
Vol 89 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Stephen L. Wood

While investigating the biology of the North American species of Hypomolyx, field workers in Manitoba found a vestigial, or short-winged, and a long-winged form under apparently identical conditions in about equal numbers. Although biological differences were nor then apparent, there was doubt as to whether they were dealing with one dimorphic species or with two distinct species, A search for morphological characters brought to light numerous differences between the two forms, supporting the view that two species were present. These differences, a description the previously unrecognized species, and notes concerning the status of the genera Hylobius and Hypomolyx are reported below.


Zootaxa ◽  
2021 ◽  
Vol 5048 (2) ◽  
pp. 151-175
Author(s):  
R.A. KAIM-MALKA ◽  
D. BELLAN-SANTINI ◽  
J.C. DAUVIN

Two new Haploops species are described from the North Atlantic Ocean: a blind species Haploops faroensis spec. nov. and Haploops truncata spec. nov. with a single pair of corneal lenses. In addition, Haploops vallifera Stephensen 1925 and Haploops similis Stephensen 1925, are re-described and the status of Haploops spinosa Shoemaker 1931, is re-established as a valid species. A table is given of the 75 morphological characters of the studied species.  


Phytotaxa ◽  
2018 ◽  
Vol 367 (3) ◽  
pp. 245 ◽  
Author(s):  
TIAGO D. M. BARBOSA ◽  
RAFAELA J. TRAD ◽  
MIKLOS M. BAJAY ◽  
MARIA I. ZUCCHI ◽  
MARIA DO CARMO E. DO AMARAL

Cabomba schwartzii was described by Rataj in 1977. The species discovered in the Brazilian Amazon was said to differ from other Cabomba species in having two sepals, two petals and a lobate petal base. According to the 1991 study of Ørgaard, C. schwartzii is similar to C. aquatica in other morphological characters (C. aquatica has flowers with three sepals and three petals) and since variation in number of floral parts is common in the genus, Ørgaard synonymized both species. After an analysis of C. schwartzii type material, other herbarium collections and location of four populations (two with C. schwartzii characteristics and two with C. aquatica characteristics), we conducted an integrated morphological and genetic study to evaluate whether or not C. schwartzii is a distinct species from C. aquatica. The results reveal the species to be distinct from each other and therefore C. schwartzii should be reestablished. The floral formula for C. schwartzii is K2 C2 A2+2 G1, versus K3 C3 A3+3 G2 for C. aquatica. A detailed species description and the geographical distribution of C. schwartzii are presented with a dichotomous key to distinguish both species, together with illustrations.


1991 ◽  
Vol 4 (2) ◽  
pp. 184-190 ◽  
Author(s):  
K L Ruoff

Streptococci requiring either pyridoxal or L-cysteine for growth were first observed 30 years ago as organisms forming satellite colonies adjacent to colonies of "helper" bacteria. Although they were previously considered nutritional mutants of viridans streptococcal species, the nutritionally variant streptococci (NVS) are currently thought to belong to distinct species of the genus Streptococcus. NVS strains may display pleomorphic cellular morphologies, depending on their growth conditions, and are distinguished from most other streptococci by enzymatic and serological characteristics and the presence of a cell wall chromophore. NVS are found as normal inhabitants of the oral cavity, and in addition to their participation in endocarditis, they have been isolated from a wide range of clinical specimens. Endocarditis caused by NVS is often difficult to eradicate; combinations of penicillin and an aminoglycoside are recommended for treatment. The unique physiological features of the NVS contribute to the difficulties encountered in their recovery from clinical specimens and may play a role in the problems associated with successful treatment of NVS endocarditis.


1970 ◽  
Vol 38 (1) ◽  
pp. 77-85
Author(s):  
ZN Tahmida Begum ◽  
Dilara Khanam

Phytoplankton from a part of the Shitalakhya river receiving effluents from a pharmaceutical industry have been studied. A total of 78 taxa were identified of which 14 belonged to Cyanophyceae, 11 Chlorophyceae, 20 Euglenophyceae and 33 Bacillariophyceae. The water body was mostly alkaline (6.6 - 8.0) and showed a wide range of variation in conductivity (135 - 4768 μS/cm), DO (anoxia to 15 mg/l), free- CO2 (3 - 29 mg/l), bicarbonate alkalinity (49 - 355 mg/l), BOD (8 - 1800 mg/l) at different locations. Pharmaceutical effluents appeared to affect diversity of phytoplankton. Three diatoms namely Fragilaria brevistriata Grun., F. construens (Ehr.) Grun. and Navicula oblonga Kütz. present in the area, are described as new for Bangladesh. Keywords: Phytoplankton; Pharmaceutical effluents; Shitalakhya River; Bangladesh DOI: 10.3329/bjb.v38i1.5127 Bangladesh J. Bot. 38(1): 77-85, 2009 (June)


1970 ◽  
Vol 4 (1) ◽  
pp. 119-127
Author(s):  
AKM Ashraful Alam ◽  
Md Mokbul Hossain

In order to assess the variability of yield contributing characters of 50 okra accessions and their interrelation effects on the yield of green pod a field experiment was undertaken at the Horticulture Farm of Bangladesh Agricultural University, Mymensingh during the period from February, 2002 to May, 2002. A wide range of variation was observed in case of weight of green pod per plant (105- 281g), days to first flowering (40-52days) and weight of individual green pod (14-26g). Moderate variation for length of green pod (12-19cm), number of green pods per plant (6-11) and yield of green pod (4-13 t/ha), lesser variation for percent of dry matter content (5-8%), number of ridges per green pod (5-9) and diameter of green pod (1-2cm) was observed. The highest genotypic coefficient of variation was observed in case of yield of green pod (GCV= 23.22%) followed by weight of green pod per plant (22.24%), weight of individual green pod (18.68%), number of ridges per green pod (13.49%), number of green pod per plant (10.84%), dry matter content of green pod (10.48%), diameter of green pod (6.90%) and length of green pod (6.24%). These characters suggested the existence of justifiable genetic distance among different cultivars. Correlation coefficient indicated that yield of green pod had highly significant positive association with weight of green pod per plant and weight of individual green pod. Path coefficient analysis showed that the weight of green pod per plant and weight of individual green pod were directly contributed towards the yield of green pod. Key words: Okra, accession, variability, yield.


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