人工饲养背摇蚊幼虫龄数和龄期的测定

本文采用了人工饲养定期取样的方法,测定了背摇蚊Chironomus dorsalis(Anderson)幼虫的龄数以及各龄的龄期。分别测量不同发育阶段幼虫的头壳长、颏中齿顶端至冠突前缘间距离、头壳宽、颏宽、颏中齿宽、触角长、触角基节长、触角比(触角基节与其余各节的长度之比)等8项指标,以期得到区分和判定幼虫虫龄的最佳形态特征及指标。运用频次分布、均差分析和回归分析对8项指标测量数据进行统计分析,结果表明,背摇蚊幼虫可分4龄,触角长可作为理想的分龄特征和分龄指标,其次是颏中齿顶端至冠突前缘间距离和颏宽。利用种群众数龄期法计算1-4龄幼虫的平均龄期分别为1.32 d、2.00 d、7.51 d和8.39 d,幼虫期共为19.22 d。     

New species of Oukuriella (Diptera: Chironomidae) from Costa Rica

The males of three new species of Oukuriella Epler are described from Costa Rica. The genus had been previously recorded only from South America. Oukuriella annamae sp. nov. has genitalia similar to O. albistyla Epler, but differs in having transverse bands on abdominal segments In, IV, VI and VII, a lower AR, no humeral setae and fewer dorsocentral setae. Oukuriella costaricense sp. nov. differs from other described species in the genus by its brown abdomen, unnotched posterior margin of tergite IX and distinctive superior volsella, with its sharply bent, thin upper arm directed medially, and digitus small and directed caudad. Oukuriella rushi sp. nov. has apices of femora tipped with brown, a brown abdomen and distinctive superior volsella, with upper arm shorter and broader, and digitus longer then O. costaricense. The female of Oukuriella costaricense is also described. This is the first female described for the genus. Based on male and female genitalia, Oukuriella is closely related to Epedilum Townes and Zavreliella Kieffer. A key is provided to separate the males of the six described species.     

中国拟枝角摇蚊属一新种记述（双翅目：摇蚊科）

记述拟枝角摇蚊属Paracladopelma 1新种:短鞭拟枝角摇蚊P.demissum sp.nov.。该新种触角比AR低,为0.60;肛尖具中肋;第9背板后缘肩形;第9背板带V型;上附器远端膨大,向外侧成三角形突起状,亚顶端具2根大刚毛,且内侧密被小刚毛;抱器端节两侧平行,中部内弯。模式标本存放于南开大学生命科学学院摇蚊学研究室。     

A new species of Dicrotendipes (Diptera: Chironomidae) from Costa Rica

The adult male of Dicrotendipes baru is described from the Dominical area of southwestern Costa Rica. The species is characterized by its elongate club-like superior volsella. This species represents the third member of the genus known from Costa Rica.     

Two new nearctic species of small orthocladiinae (Diptera: Chironomidae) with notes on ecology

Two new species of chironomid midges (Rheosmittia arcuata n.sp. and Mesocricotopus loticus n.sp.) are recognized. They may easily be missed in collections due to their small size, and difficulty in collecting from the larval microhabitat (sand substrates for R. arcuata n.sp., low order streams with depositional substrates including gravel, sand, and silt for M. loticus n.sp.). Some morphological features are given to distinguish the new species from similar congeneric forms. The distribution and some ecological information for each species are also briefly discussed.     

Two new species of the orientalis group of Rheocricotopus (Psilocricotopus) from China (Diptera: Chironomidae)

Rheocricotopus (Psilocricotopus) calviculus sp. n. and R. (P.) villiculus sp. n. from China are described as male imagines. The species are closely related to the previously described R. (P.) orientalis Wang forming a new group, the orientalis group, which eventually may deserve the rank of subgenus or even genus. The group is distinguished by lacking a humeral pit, numerous sensilla clavata on third palpomere, cuneiform wings, no or few setae on squama, long legs, banded abdomen, very long inferior volsella, gonocoxite with apical extensions, and gonostylus with a median triangular projection.     

Trophic dependencies of some larval chironomidae (Diptera) and fish species in the River Thames

Experiments are described to characterise the heterotrophic potential of Westiellopsis prolifica Janet, which fixes nitrogen under light and dark conditions. The growth of the organism in terms of dry weight increase, was more in fructose, lactose, sucrose, sorbose, galactose, glucose, sodium acetate, mannitol, sorbitol, glycerol, ethyl alcohol and butyl alcohol, when the alga was pretreated with light and subsequently incubated with the substrates in light. Mannose, xylose, acetic acid, propionic acid, fructose 1,6 di Po₄, pyruvic acid, dihydroxyacetone and succinic acid decreased the growth of the organism in the same condition. In dark incubation after pretreatment with light, as well as in the dark, Westiellopsis showed a better growth response to almost all the exogenous substrates. However, after pretreatment either with light or dark, the test organism utilised exogenous substrates quicker in light than in dark incubations. These experiments would suggest that the substrate specificity and efficiency of substrate utilisation by the alga during its heterotrophic growth are governed by the growth conditions.     

浙江西闪岛三突多足摇蚊亚属一新种（双翅目：摇蚊科）

记述采自浙江省西闪岛的三突多足摇蚊亚属1新种：杯状三突多足摇蚊Polypedilum (Tripodura) cypellum sp. nov.。该新种与哈氏三突多足摇蚊P. (T.) harteni Andersen & Mendes, 2010相似,区别于本亚属其它已知种的主要特征是具高脚杯状的上附器。文中提供了雄成虫的翅、前足胫节端部、生殖节、上附器等特征图。     

The acute toxicity of cadmium to different larval stages of Chironomus riparius (Diptera: Chironomidae) and its ecological significance for pollution regulation

Summary Acute toxicity tests using a static-with-replacement testing procedure were carried out with the four larval instars of the freshwater detritivore Chironomus riparius (Meigen). Median lethal concentrations (10, 24, 48 and 96 h LC50's) indicated great differences in sensitivity to cadmium between instars. Larvae became more tolerant with increasing age, the most resistant stage (fourth instar) having a 24 h LC50 of 2,400 mg Cd l^-1, approximately 950 times greater than the corresponding value of 2.1 mg Cd l^-1 recorded for the most sensitive (first instar) stage. These observations are discussed in relation to the establishment of water quality standards.     

A six-year study of abundance and voltinism of Chironomidae (Diptera) in an Illinois cooling reservoir

The chironomid fauna of Baldwin Lake, an off-stream closed-cycle cooling reservoir for an 1800-megawatt coal-fired power plant, was sampled semi-monthly to monthly at four stations for six years, beginning five months after the reservoir was filled and ending 23 months after the third unit of the power plant went into operation. In the main basin three species dominated: Coelotanypus concinnus (Coquillett), Procladius bellus (Loew), and Tanypus stellatus Coquillett. The last did not become established until the lake was two years old, probably because temperatures were too low the first winter. Populations of all three species were initially large and sharply fluctuating, but later became smaller and less fluctuant in C. concinnus and P. bellus, due, probably, to more intense predation on them. Only in T. stellatus were changes in voltinism clearly evident: it changed from bivoltine to tri- and quatrivoltine as degree-days of heat increased. Photoperiod also affected its life cycle, as evidenced by synchronous development of summer generations each year. Temperature and perhaps food supply affected development time of its overwintering generation. All three species tolerated a temperature of 38 °C; their populations were kept low in the discharge channel by the current, not the temperature. Six species of Chironominae were sporadically abundant in the discharge channel.     

Seasonal influence on head capsule deformities in Chironomus zealandicus (Hudson) (Diptera: Chironomidae)

The natural incidence of deformities in the head capsules of Chironomus zealandicus was investigated at four lake sites in the central North Island (New Zealand) in summer (December) of 1994, 1995 and 1996, and winter (June) of 1995 and 1996. Significant differences were observed in deformities between sites and seasons. Individuals from Hamurana Stream, a relatively clean site, had the lowest incidence of deformities. However, there were still significant numbers of deformed chironomids. The incidence of deformity increased in summer in larvae from all sites except Hamurana Stream. No seasonal differences were observed in larvae from Hamurana Stream. There are indications that substrate type, season and genetic factors, as well as sediment chemistry may have collectively contributed to the incidence of head capsule abnormalities in C. zealandicus.     

The distribution of Heterotrissocladius oliveri Saether (Diptera: Chironomidae) in Lake Michigan

Fifty one chironomid species were identified from 504 samples collected at depths ranging 8 to 267 m in Lake Michigan, U.S.A. Heterotrissocladius oliveri Saether occurred in 32% of these samples and had an average abundance of 22 m^–2 which was similar to other estimates from the Great Lakes. Maximum average lake-wide density was at 30 to 60 m (41 m^–2). At depths 60 m, H. oliveri was the dominant chironomid species comprising 75% of total Chironomidae. The substrate preference of H. oliveri differed within each depth regime considered: at 30–60 m, 2–3 ; at 60–120 m, 3–5 , 7–9 ; and at 120–180 m, 6–8 . Abundance was notably reduced at all depths in substrates characterized as medium silt (5–6 ). On a lake-wide basis, the distribution pattern suggested H. oliveri was most numerous from 30 to 60 m along the southwestern, eastern, and northern shorelines and at 60–120 m depths along the southern and eastern shorelines. Increased abundance in the South Basin was concurrent with evidence of increased sedimentation at 60 to 100 m. However, in several other areas of the lake, high densities were associated with medium to very fine sands relatively free of silts and clays. This observation suggested occurrence of H. oliveri was minimally affected by sediment type.Widely variable, but generally elevated water temperatures likely prevent H. oliveri from establishing a substantial population density at depths < 30 m. With increased depth, temperature fluctuation is negligible and food is more stable, though the source is variable. Factors limiting abundance of H. oliveri at depths 30 m were related to decreased food supply due to distance from shore, food sources of lower value (clays), and, most importantly, to reproductive replenishment.Although still oligotrophic in nature, high density occurrences in both high and low sedimentation areas of the lake suggest the trophic indicator status of H. oliveri might be broader than previously thought.     

中国真开氏摇蚊属一新种及一新记录种记述（双翅目：摇蚊科）

记述真开氏摇蚊属Eukiefferiella Thienemann 1新种:盖真开氏摇蚊E. celata sp. nov.和1种中国新记录种: 翘叶真开氏遥蚊E. brehmi Gouin, 1943;提出兵库真开氏摇蚊E. togaeuquinta Sasa & Okazawa, 1992为翘叶真开氏摇蚊 E. brehmi Gouin,1943的新异名。     

Food selection of Tanytarsus gracilentus larvae (Diptera: Chironomidae): An analysis of instars and cohorts

Gut contents of the detritivorous Tanytarsus gracilentus larvae were studied at one site in Lake Myvatn, Iceland. Samples were collected with a sediment corer. Sediment samples were taken from the surface of the intact core before the larvae were collected. Gut contents were compared between different larval instars and cohorts, and to the surface sediment. The composition of the gut contents of all instars was different from that of the sediment surface. The first instar selected small diatoms of the genus Fragilaria, as single and paired cells, and the fourth instar selected detritus items of more variable size and origin. Apart from the third instar larvae, there were similar trends in food selectivity between the same instar of different cohorts. No major changes occurred in the composition of the surface sediment during the time of this study.     

Cytotaxonomy of Chironomidae (Diptera) from Lake Shabla (Bulgaria): cytogenetic evidence for introgressive hydribization

Twenty-two chironomid species were found in Lake Shabla. Five species (Chironomus bonus, Dicrotendipes lobiger, Kiefferulus tendipediformis, Cricotopus suspiciosus and Cricotopus sp.) are new for Bulgaria. Their karytopes are described for the first time.Cytogenetic studies of two closely related chironomid species, Glyptotendipes glaucus and G. pallens, show that in one area of sympatry (Lake Shabla, Bulgaria) about 2.5% of the naturally occuring individuals are hybrids. In most cases, in this hybrid, 1st, IInd and IIIrd chromosomes correspond fully to the chromosomes of G. glaucus. The IVth chromosome is a hybrid, with one homologue of the species G. glaucus; the other homologue is derived from G. pallens. Introgressive hybridization is of particular importance to the production of these combinations. Despite hybridization, natural selection appears to maintain the essential integrity of each separate gene pool.     

中国多足揺蚊属指名亚属一新种(双翅目:摇蚊科)

记述中国多足摇蚊属指名亚属Polypedilum (s. str.) Kieffer 1新种——等跗多足摇蚊Polypedilum (Polypedilum) aequabe, sp. nov.,该新种雄虫可借以下组合特征与本亚属其它已知种类相区别:后足第 2 与第 3 跗节等长,肛尖具侧毛,上附器外侧毛位于近端部,下附器端部膨大。模式标本存放在南开大学生命科学学院摇蚊研究室。正模:♂,四川乡城硕曲河,2 700 m,1996-Ⅵ-12,灯诱,王新华采;副模:18♂♂,同正模;1♂,云南丽江石鼓冲江河,1750m,1996-Ⅴ-25,灯诱,周长发采。     

Phenology and life history of Belgica antarctica, an Antarctic midge (Diptera: Chironomidae)

ABSTRACT.

• 1 An account of the life-history with emphasis on phenology and number of instars is presented for Belgica antarctica Jacobs, the southernmost holometabolous insect.
• 2 Contrary to earlier reports, Belgica has four instars, in common with most other chironomids. Mean head capsule lengths varied between different populations but no overlap was found between discrete size classes of successive instars.
• 3 Belgica overwinters in all four instars.
• 4 Relative frequency of different instars from samples taken through the season indicates that a 2-year life-span is the commonest pattern.
• 5 Emergence of adults is relatively synchronous. Belgica exhibits protandry, which may be established at the time of pupation.

     

Chironomidae (Diptera) of Baldwin Lake,Illinois, a cooling reservoir

The chironomid fauna of Baldwin Lake, a closed-cycle cooling reservoir for a power plant, was sampled monthly to semi-monthly for one year at four stations, two in the discharge channel and two in the main basin. Qualitative samples were also taken elsewhere and with multiple-plate samplers. Twenty-four species were collected. Annual mean population density was less than 100 larvae m^–2 in the channel, 1037 M^–2 in the main basin. Three species of Tanypodinae formed over 96 percent of the larval population in the main basin: Tanypus stellatus Coquillett, Procladius bellus (Loew), and Coelotanypus concinnus (Coquillett). The principal species on the multiple-plate samplers were Dicrotendipes nervosus (Staeger), Glyptotendipes lobiferus (Say), and Parachironomus monochromus (Wulp). Temperatures of 35°C or more in the channel virtually eliminated the chironomids, whereas temperatures up to 32°C in the main basin increased the number of generations of T. stellatus from the usual two to four at Station 3 and three at Station 4. Station 3 had almost 1,000 degree-days more heat than Station 4.     

A review of selected South- and East Asian Tanytarsus v.d. Wulp (Diptera: Chironomidae)

Male and pupa of Tanytarsus calorifontis sp. n. are described. Diagnoses, hypopygium drawings for the examined species and distribution are given for: Tanytarsus akantertiusSasa & Kamimura, T. angulatus Kawai, T. atagoensis Tokunaga,T. bathophilusKieffer, T. boninensis Tokunaga, T. formosae (Kieffer), T. formosanusKieffer, T. infundibulusChaudhuri & Datta, T. kikuchiiSasa, Kawai & Ueno, T. konishii Sasa & Kawai, T. mcmillani Freeman, T. mendax Kieffer, T. miyakobrevis Sasa & Hasegawa, T. monstrosus Chaudhuri et al., T. ogasaquartus Sasa & Suzuki, T. ogasatertius Sasa & Suzuki, T. okuboi Sasa & Kikuchi, T. oscillans Johannsen, T. ovatus Johannsen, T. oyamai Sasa, T. pollexus Chaudhuri & Datta, T. shouautumnalis Sasa, T. shoudigitatus Sasa, T. takahashii Kawai & Sasa, T. tamaundecimus Sasa, T. tonebeceus Sasa & Tanaka, T. tusimatneousSasa & Suzuki, T. unagiseptimus Sasa, T. uraiensis Tokunaga, T. yakuheiusSasa & Suzuki and T. yunosecundus Sasa. Tanytarsus ikiefeus Sasa & Suzuki is a new junior synonym of T. konishii. Tanytarsus ikifegeus Sasa & Suzuki, T. miyakoflavus Sasa & Hasegawa,T. oyabepallidus Sasa, Kawai & Ueno, T. simantoopeus Sasa et al. and T. tusimatheius Sasa & Suzuki are new junior synonyms of T. okuboi. Tanytarsus nippogregarius Sasa & Kamimura is a new junior synonym of T. bathophilus. Tanytarsus cultellus Chaudhuri & Datta and T. sibafegeus Sasa et al. are new junior synonyms of T. oscillans.Tanytarsus insulus (Guha et al., 1985) is a new junior synonym of T. ovatus. Tanytarsus sakishimanus Sasa & Hasegawa, T. vinculus Chaudhuri et al., T. parvistylus Chaudhuri & Datta, T. fusciabdominalis Guha et al. and T. euformosanus Kikuchi & Sasa are new junior synonyms of T. formosanus. Tanytarsus tsutaprimus Sasa, T. tokarajekeus Sasa & Suzuki, T. tusimatlemeus Sasa & Suzuki, T. tusimatopeus Sasa & Suzuki and T. yakugeheuus Sasa & Suzuki are new junior synonyms of T. shouautumnalis. Tanytarsus togasiroidus Sasa & Okazawa is a new junior synonym of T. shoudigitatus. Tanytarsus tusimatjekeus Sasa & Suzuki and T. tusimatkeleus Sasa & Suzuki are new junior synonyms of T. akantertius, and Tanytarsus tusimatpequeus Sasa & Suzuki is a new junior synonym of T. tusimatneous. Virgatanytarsus toganiveus (Sasa & Okazawa), Cladotanytarsus utonaiquartus (Sasa) and Zavrelia tusimatijeus (Sasa & Suzuki), all previously placed in Tanytarsus, are new combinations.