A test of adaptive divergence in a newly discovered host association of the soapberry bug Jadera haematoloma on Mexican buckeye,Ungnadia speciosa

Host races represent an important step in the speciation process of phytophagous insects as they reflect the maintenance of genetically divergent host-associated populations in the face of appreciable gene flow. The red-shouldered soapberry bug, Jadera haematoloma (Herrich-Schäffer) (Hemiptera: Rhopalidae), is an oligophagous seed predator with a history of host race evolution on plant associations in the (soapberry) family Sapindaceae. Soapberry bugs are a model group for understanding rapid ecological adaptation to their hosts, and hence good candidates for investigating evolutionary divergence in host associations over short timescales. Here, we describe the recent discovery of Mexican buckeye, Ungnadia speciosa Endl., as a host of J. haematoloma in a region of the Chihuahuan desert including west Texas and southeastern New Mexico, USA. This host differs from J. haematoloma’s previously recorded hosts in the Sapindaceae in seed chemistry, ecology, and phylogeny. The tendency toward rapid, host-associated adaptations by populations of J. haematoloma and the unique biology of the newly discovered Ungnadia host create the opportunity for potential host race formation, as it overlaps geographically with two previously recorded host plants in this region – the native western soapberry tree, Sapindus saponaria var. drummondii (Hook & Arn.), and the non-native goldenrain tree, Koelreuteria paniculata Laxm. We explore the possibility of host race formation on Ungnadia-associated insects by testing for host-associated differentiation in morphology and feeding behaviors. We find evidence of differentiation in the length of the mouth parts, which is an ecologically relevant feeding trait between host plant species with larger or smaller seed capsules. This divergence is maintained in the face of potential gene flow by reproductive isolation in the form of habitat isolation, which we detect in host preference trials. Together, our results demonstrate that soapberry bugs associated with this newly discovered host exhibit morphological and behavioral traits consistent with host race formation, but additional work is required to confirm its state along the speciation continuum.     

The systematic relevance of fruit and seed anatomy and morphology of Akania (Akaniaceae)

The fruit and seed anatomy and morphology of Akania bidwillii , the monotypic genus in the Akaniaceae, have been studied in an effort to clarify its systematic position. The loculicidal (1,2-) 3-locular fruit with Ugnified fibrous 6–7-layered endocarp is clearly of capsular type. Seeds of Akania are relatively large, smelling of bitter almonds, abundantly albuminous, with straight dicotyledonous embryo. The seed coat of Akania is exo-mesotestal with fully obliterated tegmen in early stages; 1-layered exotesta represented by columellar thick-walled cells with numerous invaginations of inner cell walls; mesotesta 25–35-layered, composed of thick-walled, but not lignified mostly rounded sclereids filled with tanninlike substances, the innermost part of mesotesta is aerenchymatous, sometimes collapsed, and traversed by 6(8) postchalazal vascular bundles, 2–3 layers of endotesta composed of enlarged cuboid cells with heavily thickened walls. Evidence mainly from seed morphology and anatomy of seed coats emphasizes the anomaly of the traditional inclusion of Ankaniaceae in the Sapindales, being quite distinct in spermoderm structure and origin from both Sapindaceae and Staphyleaceae in particular as well as from other families of the order, excepting somewhat anomalous exo-mesotestal Bretschneideraceae. Furthermore, seed anatomy does not confirm any relationships with Capparales. It is suggested that Akaniaceae together with Bretschneideraceae constitute a distinct relict side-branch of connaraceous-sapindaceous ancestry tracing back to primitive exo-mesotestal Resales. On the basis of available data of seed coat anatomy it is appropriate to remove archaic Akaniaceae with Bretschneideraceae from more advanced Sapindales. Furthermore, widi the addition of more data on carpology and seed anatomy of basal Rosidae the systematic position of the family should be redefined in terms of its primitiveness and the lack of close relationships with Sapindales.     

γ-Glutamyl transpeptidase of the ackee plant

The enzyme γ-glutamyl transpeptidase was purified from seeds of immature ackee fruit (Blighia sapida; Sapindaceae) by salt fractionation and gel filtration on Biogel P-10 and P-200. The procedure, which differs from an earlier one applied to kidney bean fruit, achieves 9.8% yield and 577-fold purification. The enzyme is also present in other parts of the fruit and in leaves. A MW of 12 500 was found by SDS-polyacrylamide gel electrophoresis, a value much lower that that reported for the enzyme from kidney bean fruit. Neutral or amino sugar accounts for 10% of the dry weight. In vitro, the enzyme catalysed synthesis of an unusual γ-glutamyl dipeptide which occurs in ackee seeds, using glutathione as glutamyl group donor. The enzyme mechanism was of the double displacement (ping-pong) type.     

Two new species of Serjania section Serjania (Sapindaceae)

Two new species ofSerjania sect.Serjania,Serjania neei from Bolivia andS. rhytidococca from Mexico, are described, illustrated, and compared with their closest relatives.

---

Resumen  En el presente artículo se describen, se ilustran y se comparan con los parientes mas cercanos las nuevas especiesSerjania neei de Bolivia yS. rhytidococca de México, ambas pertenecientes a la secciónSerjania.

     

中国无患子科的花粉形态及其系统学意义

利用扫描电镜对国产无患子科(狭义,Sapindaceae)23属30种1变种植物的花粉形态进行了观察。结果显示,该科花粉粒多为扁球形,部分为长球形,少数为球形或近球形,极面观多为三角形;从花粉萌发孔类型看,大多数种类具三沟孔,有的形成合沟,少数仅具三孔而无沟;从花粉外壁纹饰看,多数花粉外壁具网状或条纹状雕纹,少数花粉的外壁具刺状或颗粒状纹饰。花粉形态特征支持文冠果亚科(Xanthoceroideae)以及广义鳞花木属(Lepisanthes)概念,并支持仍将茶条木属(Delavaya)置于车桑子亚科(Dodonaeoideae)。观察发现黄梨木(Boniodendron minus)与栾树属(Koelreuteria),龙眼属(Dimocarpus)、荔枝属(Litchi)与韶子属(Nephelium)从花粉形态上表现出较近的亲缘关系。基于花粉形态特征编制了国产无患子科分属检索表。     

基于叶片解剖特征分析三种无患子科果树的亲缘关系

采用石蜡切片和组织离析法,对3种无患子科果树的10份种质叶片横切及表皮解剖特征进行观察,并采用聚类分析对其亲缘关系进行初步研究。结果表明：10份试材均为异面叶,叶横切结构分为表皮、叶肉和叶脉3部分。中脉厚度总体上龙眼最大、龙荔次之、荔枝最小,差异显著。荔枝的中脉横切面为圆三角形,龙眼近似半圆形,龙荔则近似扁圆形。不同试材的叶片、上表皮和下表皮、栅栏组织及海绵组织的厚度分别为175.23~318.84、11.18~25.13、7.49~20.43、50.01~124.59和84.0~173.64μm,栅栏组织细胞有2~3层。此外,叶脉突起度、栅栏组织与海绵组织厚度之比、叶片组织结构紧密度和叶片组织结构疏松度分别为2.65~5.77、0.52~0.82、28.89％~39.95％和44.89％~55.57％。荔枝的表皮细胞较小、多边形,垂周壁为弧形,下表皮无表皮毛,气孔器呈长椭圆形;龙眼的表皮细胞较大、不规则形,垂周壁深波状,下表皮具表皮毛,气孔椭圆形或近圆形;龙荔的表皮细胞与龙眼相近,但垂周壁为波状。聚类分析显示,10份试材首先聚为两大类,其中第一类是荔枝属,第二类是龙眼属;然后又分为4个亚类,三月红和龙荔各自单独聚为一个亚类。     

Identification of asymmetrically winged samaras from the Western Hemisphere

A key is presented for use in identifying asymmetrically winged fruits (samaras) with either proximal or distal locules. It aids identification based on dispersed fuit morphology and can be used to identify undetermined extant herbarium specimens or fossil fruits to the correct extant family and genus. The 39 genera from 11 families (Aceraceae, Anacardiaceae, Fabaceae, Malpighiaceae, Phytolaccaceae, Polygalaceae, Polygonaceae, Rutaceae, Sapindaceae, Trigoniaceae, Ulmaceae) are distinguished on the basis of wing venation, size of fruit, presence and position of attachment surface, presence and type of subsidiary wings on the ovary wall. ornamentation, size and shape of the ovary, locule position, shape of locule cross section, style position and ornamentation, distinction between ovary wall and wing, and angle of attachment between individual samaras. The developmental origins of some of these features are discussed.     

Sporogenesis and gametogenesis of Delavaya toxocarpa (Sapindaceae) and their systematic implications

In order to investigate the embryological characteristics of Delavaya toxocarpa Franch. and provide a basis for further understanding the phylogeny within Sapindaceae s.l., we studied the sporogenesis and gametogenesis of D. toxocarpa using the conventional paraffin section method. The results were as follows: anthers are tetrasporangium; tapetum is typically secretory type; cytokinesis in the microsporecyte meiosis is of the simultaneous type and microspore tetrads are tetrahedral; mature pollen contains two cells; the ovary is bilocular with two ovules per locule; placentation is axial; the ovule is amphitropous, bitegmic, and crassinucellate; the chalazal megaspore in a linear tetrad becomes functional; and the development of megaspore is of the polygonum type. Most similarities shared by the species observed suggest that the species and genera of Sapindaceae s.l. have phylogenetic consistency. The distinctive trait, lacking hypostase, indicatesDelavaya (and Handeliodendron) might be more primitive than other genera in Sapindaceae. Moreover, some characters, such as opposite palmate compound leaf, apical thyrse, rounded seed without wing, 2 hemitropous ovules per locule, and lacking aril, indicate the close relationship between Delavaya, Aceraceae, and Hippocastanaceae. The preliminary data about the embryological and morphological characteristics in Delavaya might justify the basic systematic position of this genus in the family Sapindaceae s.s.     

掌叶木的花器官发生及其系统学意义

利用扫描电子显微镜和光学显微镜观察了掌叶木的花器官发生过程。观察结果表明: 花序原基最先发生, 然后形成两个大小不一的花原基; 萼片原基的发生不同步, 螺旋状向心发生; 4-5枚花瓣原基以接近轮状方式近同时发生; 不存在花瓣-雄蕊复合原基; 7-8枚雄蕊原基为近同时发生, 其生长较花瓣原基快; 心皮原基最后发生, 3枚心皮原基为同时发生。花为单性花。在雌花中, 子房膨大而雄蕊退化。在雄花中, 雄蕊正常发育, 子房退化。讨论了掌叶木花器官发生和发育的系统学意义。     

Pendulaosides A and B. Two acylated triterpenoid saponins from Harpullia pendula seed extract

Two new acylated triterpenoid saponins named pendulaosides A and B as well as the known phenolic compounds methyl gallate, gallic acid, 1,2,3,6-tera-O-galloyl-β-d-glucose and 1,2,3,4,6-penta-O-galloyl-β-d-glucose, were isolated from the seeds of Harpullia pendula. The structures of pendulaosides A and B were determined using extensive 1D and 2D NMR analysis and mass spectrometry as well as acid hydrolysis, as 3-O-β-d-glucopyranosyl-(1→2)-[α-L-arabinofuranosyl-(1→3)]-β-d-glucuronopyranosyl-22-O-angeloyl-3β,16α,22α,24β,28-pentahydroxylolean-12-ene and 3-O-β-d-glucopyranosyl-(1→2)-[α-L-arabinofuranosyl-(1→3)]-β-d-glucuronopyranosyl-16-O-(2-methylbutyroyl)-3β,16α,22α,24β,28-pentahydroxylolean-12-ene, respectively. To the best of our knowledge the two triterpene parts 22-O-angeloyl-3β,16α,22α,24β,28-pentahydroxylolean-12-ene and16-O-(2-methylbutyroyl)-3β,16α,22α,24β,28-pentahydroxylolean-12-ene have never been characterized before. The two isolated saponins were assayed for their in-vitro cytotoxic activity against the three human tumor cell lines HepG2, MCF7 and PC3. The results showed that pendulaoside A exhibited moderate activity on PC3 cell line with IC50value equal to 13.0 μM and weak activity on HepG2 cell line with IC50 value equal to 41.0 μM. Pendulaoside B proved to be inactive against the three used cell lines.