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Heteranassa Smith (Erebidae, Omopterini), native to the southwestern United States and Mexico, includes two recognized species, namely Heteranassa
mima (Harvey) and Heteranassa
fraterna Smith. These are separated mainly by subtle differences in wing color and pattern, leading to speculation about the validity of the described species. This study examines variation in external and internal morphology across the geographic range of the genus, aiming to clarify species limits, describe morphology, and provide a comprehensive assessment of variation within the genus. Results indicate that Heteranassa
fraterna
syn. n., is a junior synonym of Heteranassa
mima. 相似文献
3.
Federico A. Agrain Matthew L. Buffington Caroline S. Chaboo Maria L. Chamorro Matthias Sch?ller 《ZooKeys》2015,(547):133-164
Although some species of Cryptocephalinae (Coleoptera: Chrysomelidae) have been documented with ants (Hymenoptera: Formicidae) for almost 200 years, information on this association is fragmentary. This contribution synthesizes extant literature and analysizes the data for biological patterns. Myrmecophily is more common in the tribe Clytrini than in Cryptocephalini, but not documented for Fulcidacini or the closely-related Lamprosomatinae. Myrmecophilous cryptocephalines (34 species in 14 genera) primarily live among formicine and myrmecines ants as hosts. These two ant lineages are putative sister-groups, with their root-node dated to between 77–90 mya. In the New World tropics, the relatively recent radiation of ants from moist forests to more xeric ecosystems might have propelled the association of cryptocephalines and ant nests. Literature records suggest that the defensive behavioral profile or chemical profile (or both) of these ants has been exploited by cryptocephalines. Another pattern appears to be that specialized natural enemies, especially parasitoid Hymenoptera, exploit cryptocephaline beetles inside the ant nests. With the extant data at hand, based on the minimum age of a fossil larva dated to 45 mya, we can infer that the origin of cryptocephaline myrmecophily could have arisen within the Upper Cretaceous or later. It remains unknown how many times myrmecophily has appeared, or how old is the behavior. This uncertainty is compounded by incongruent hypotheses about the origins of Chrysomelidae and angiosperm-associated lineages of cryptocephalines. Living with ants offers multiple advantages that might have aided the colonization of xeric environments by some cryptocephaline species. 相似文献
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The Chinese species of the genera Omicrogiton Orchymont, 1919, Peratogonus Sharp, 1884 and Mircogioton Orchymont, 1937 are reviewed, diagnosed and keyed. Mircogioton and Omicrogiton are reported for the first time from China, Peratogonus for the first time for mainland China. Five species are recognized: Omicrogiton
coomani Balfour-Browne, 1939 (Guangdong, Hongkong), Omicrogiton
hainanensis
sp. n. (Hainan), Omicrogiton
roberti
sp. n. (Hainan), Mircogioton
coomani Orchymont, 1937 (Yunnan), and Peratogonus
reversus Sharp, 1884 (Guangdong, Jiangxi, Taiwan). Lectotype of Omicrogiton
coomani is designated. Mircogioton
cognitus (Malcolm, 1981), syn. n. is considered a junior subjective synonym of Mircogioton
coomani Orchymont, 1939. Species of Mircogioton and Omicrogiton inhabit decaying banana trunks, whereas Peratogonus
reversus was always collected from moist forest leaf litter. 相似文献
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There are four species of Gymnetron in China recorded to date including Gymnetron
miyoshii Miyoshi, 1922, Gymnetron
villosipenne Roelofs, 1875, Gymnetron
auliense Reitter, 1907 and Gymnetron
vittipenne Marseul, 1876, of which the last two are new country records. The pre-imaginal stages including eggs, mature larvae and pupae of Gymnetron
miyoshii, Gymnetron
auliense and Gymnetron
vittipenne are described and illustrated. In addition, their diagnostic characters (larvae and pupae) are discussed and differentiated, and notes on some of their biological parameters are provided. Potential ecological impacts between Gymnetron weevils and their host Veronica spp. also are provided. 相似文献
8.
《Grana》2012,51(6):408-423
AbstractIn Euphorbiaceae tribe Hippomaneae is the pantropical genus Microstachys, comprised by 24 species, mostly from Brazil. Palynological studies with several representatives of the genus are scarce. The purpose of this study was to describe the pollen morphology of Microstachys and find possible differentiating characteristics between its species. Ten species of the genus were analysed, represented by 21 herbarium collections. Their pollen grains were acetolysed, measured and photographed under light microscopy (LM) and scanning electron microscopy (SEM). The analysed species possess pollen in monads, of small to medium size, isopolars, amb distincticly trilobed, oblate-spheroidal, prolate-spheroidal or subprolate, tricolporate with narrow and very long colpi, almost fused at the poles sometimes forming an invagination with tapering ends and margo of the colporus wide to very wide and psilate; endoapertures lalongate to very lalongate with tapering ends, presence of a narrow costae distinct in the endoaperture; exine microreticulate homobrochate, walls with simple columella; at the mesocolpus the sexine separates from the nexine forming cavea; and sexine always thicker than the nexine. Microstachys is a stenopalynous genus, despite its species varying in pollen size, shape and width of the cavea, margo of the colporus, and length of the endoapertures, demonstrating taxonomic value, and indicating a contribution towards future systematic analyses. 相似文献
9.
利用扫描电镜研究了茄科(Solanaceae)天仙子族(Hyoscyameae)中国特有属马尿泡属( Przewalskia Maxim.)马尿泡( Przewalskia tangutica Maxim.)和天仙子属( Hyoscyamus L.)天仙子( Hyoscyamus niger L.)的花器官发生和发育,研究结果表明:马尿泡和天仙子花器官的发生和发育具有以下3个共同特征:1)符合Hofmeister规律, 即新器官的发生首先出现在花顶已经存在的器官之间;2)花冠的发育模式符合茄科植物所具有的"后合瓣"("late sympetaly")现象,即花瓣单独发生但后来又通过它们基部分生组织的融合而连合起来;3)花被五基数且花器官原基发生顺序为向心发育.但是它们的花萼原基具有不同的发生方式.天仙子花萼裂片原基的发生方式为环状发生;马尿泡花萼裂片原基的发生方式为螺旋状发生,但5个花萼裂片原基在都出现后就连成了一个环.马尿泡是介于天仙子属和山莨菪属之间的类群,它比天仙子属原始但较山莨菪属进化. 相似文献
10.