Insect pollination and floral mechanisms in South African species ofSatyrium (Orchidaceae)

The morphologically diverse flowers in the genusSatyrium reflect adaptations to a wide range of pollinators. Several recently discovered pollination systems inSatyrium are described and illustrated here; these include pollination by solitary bees, carrion flies, butterflies and moths. Two basic types of floral mechanism are recognised inSatyrium: (1) Species pollinated by lepidoptera and birds have long floral spurs and plate-like viscidia seated in lateral rostellum notches; these viscidia become attached to the proboscis or bill of the pollinator. (2) Species pollinated by flies and bees have relatively short floral spurs and globose viscidia seated in terminal rostellum notches; these viscidia become attached to the face, thorax or eyes of the pollinator.     

Spiranthes ovalis var. Erostellata (Orchidaceae), a new autogamous variety from the Eastern United States

Examination of flowers from herbarium specimens ofSpiranthes ovalis revealed two kinds of column structure. Some plants, including the type, have flowers with a normally developed rostellum and viscidium; other plants that have flowers in which these structures are entirely lacking are here described asSpiranthes ovalis var.erostellata. Self-pollination in the new variety was proven by pollinia removal and observation of plants in insect-proof cages. The var.erostellata has a somewhat smaller perianth with sepals 3.5–5 instead of 4–6.1 mm long and is more common and more widespread than the typical variety.     

Histological and Micro-CT Evidence of Stigmatic Rostellum Receptivity Promoting Auto-Pollination in the Madagascan Orchid Bulbophyllum bicoloratum

Background

The rostellum, a projecting part of the gynostemium in orchid flowers, separates the anther(s) from the stigma and thus commonly prevents auto-pollination. Nonetheless, as a modified (usually distal) portion of the median stigma lobe, the rostellum has been frequently invoked of having re-gained a stigmatic function in rare cases of orchid auto-pollination. Here it is shown that a newly discovered selfing variant of Madagascan Bulbophyllum bicoloratum has evolved a modified rostellum allowing the penetration of pollen tubes from in situ pollinia.

Methods

Gynostemium micro-morphology and anatomy of selfing and outcrossing variants of B . bicoloratum was studied by using light and scanning electron microscopy and histological sections. Pollen tube growth in the selfing variant was further observed via X-ray computed microtomography (micro-CT), providing 3D reconstructions of floral tissues at a micron scale.

Findings

Selfing variants possess a suberect (‘displaced’) rostellum rather than the conventional, erect type. Very early in anthesis, the pollinia of selfers are released from the anther and slide down onto the suberect rostellum, where pollen tube growth preferentially occurs through the non-vascularized, i.e. rear (adaxial) and (semi-) lateral parts. This penetrated tissue is comprised of a thin layer of elongate and loosely arranged cells, embedded in stigmatic exudates, as also observed in the stigmatic cavity of both selfing and outcrossing variants.

Conclusions

Our results provide the first solid evidence of a stigmatic function for the rostellum in orchid flowers, thereby demonstrating for the first time the feasibility of the micro-CT technique for accurately visualizing pollen tube growth in flowering plants. Rostellum receptivity in B . bicoloratum probably uniquely evolved as an adaptation for reproductive assurance from an outcrossing ancestor possessing an erect (non-receptive) rostellum. These findings open up new avenues in the investigation of an organ that apparently re-gained its ‘primordial function’ of being penetrated by pollen tubes.     

POSTPOLLINATION PHENOMENA IN ORCHID FLOWERS. V. PARTICIPATION BY THE ROSTELLUM AND GYNOSTEMIUM TIP

Removal of the rostellum following pollination does not prevent stigmatic closure in Cymbidium flowers and has a minimal effect on straightening of the gynostemium (column). However, this treatment does depress anthocyanin levels in both gynostemia and labella. Excision of the rostellum 30 or 60 min after pollination has a more pronounced effect than removal after 150 min. Stigmatic closure is not inhibited by removal of the gynostemium tip, but column swelling is reduced. These findings are discussed relative to rostellar functions and theories regarding their origin.     

The column types of Neottia and Archineottia of the family Orchidaceae and their taxonomic and phylogenetic significance

The column is the most characteristic part of an orchid flower. It is considered to be formed by the union of stamens with a central style and stigma. In the Apostasieae, for example, the column is rather primitive in the stamens and style only partially united, whereas in the majority of higher orchids it becomes more advanced through a eomplete union of them into a single organ. Within the family, indeed, the column structure is greatly diversified and of great taxonomic significance. It is interesting to note that a great range of diversity of column structure is bund in Neottia (sensu lato), a small but widespread genus consisting of 14 species, about two thirds of which, however, are of local occurance and seem to be little known to many botanists. In some speeies of this genus we find a very primitive column structure which is quite unique in the family, while in the others it is much more complicated. In all, five types of their column structure can be distinguished as fol- lows: (1) column rather longer; anther erect with a short filament attached to the back of the column near the apex; stigma terminal; neither clinandrium nor rostellure; (f. 2, 4) (2) as the preceding, 'except for the stigma more or less curved foreward and filament longer; (f. 6, 8) (3) column rather longer with a clinandrium at its summit, upon which a sessile and incumbent anther sits; rostellum large, horizontally projecting out over the concave stigma situated in the front of the column; (f. 10, 13, 15, 17) (4) as the preceding, except, for the anther and rostellum almost erect, and the stigma more or less bilabiate; (f. 19,21) (5) column very short; anther and rostellum erect; stigma lamellate, erect; reflexed and almost clasping the rostellum. (f.,2g) In these .five types, with the exception of the first one in which the labellum (the median petal) is very similar to the lateral: petals, they all possess zygomorphic perianth with labellum bilobed or entire which is quite different from the two lateral petals. Here, we see a great change in the column structure from one form with stamen and style not fully united to another form in which they have been well fused. Speaking strictly, these are two sorts of entirely different column structure. The former one, represented by (1) and (2) as stated above, is, in fact, an incomplete or s very primitive column in having a terminal stigma and an erect stamen with its free filament attached to the back of the column; and the absence of clinandrium and rostellum. Furthermore, there exists on the back of the column a thick ridge with its upper end joined to the filament, with which it is of the same texture and appearance. In Neottia pantlingii (=Arohineottia pantlingii) the free filament is even rather longer than the ridge, (f. 6) while in the other three species (f. 2, 4, 8) they are shorter. It is in my opinion the lower part of the filament adnate to the compound style or column. This is another fact of interest perhaps not occuring in any other living orchids. On the other hand, the latter one, represented by (3), (4) and (5), is a more advanced column structure, in which a higher level of specialisation with well-developed clinandrium and rostellum is reached. The stigma becomes shallow depressed on the anterior side of the column, or sometimes in the form of somewhat a bilabiate lip projecting out before or under the long rostellum. This is apparently a complete column both in structure and function quite different from the former and, contrarily, much like that of Listera. Basing upon the facts just mentioned, we may subdivided Neottia (sensu lato) into two distinct genera, with two and three sections respectively. They are as follows: 1. Archineottia S. C. Chen, gen. nov. (1) Sect. Archineottia 1) A. gaudissartii (Hand.-Mzt.) S. C. Chen, comb. nov. (China) 2) A. microglottis (Duthie) S. C. Chen, comb. nov. (India) (2) Sect. Furciila S. C. Chen, sect. nov. 3) A. pantlingii (W. W. Smith) S. C. Chen, comb. nov. (Sikkim) 4) A. smithiana (Schltr.) S. C. Chen, comb. nov. (China) 2. Neottia Guett. (1) Sect. Listeroides S.C. Chen, sect. nov. 1) N. listeroides (L.) Rchb. f. (China, Sikkim, Kashmir) 2) N. camtschatea (L.) Rchb. f, (China, Soviet Union) 3) N. megalochila S. C. Chen, nom. nov. (China) 4) N. inayatii (I)uthie) Schltr. (Pakistan, Kashmir) 5) N. tenii Schltr; (China) (2) Sect. Neottia 6) N. papilligera Schltr. (Chinas: Japan, Korea, Soviet Union, Sikkim) 7) N. nidus-avis (L.) L. C. Rich. (Europe, Iran, Western Siberia) 8) N. brevilabris Tang et Wang: (China) (3) Sect. Hologlossa S. C. Chen, sect. nov. 9) N. acuminata Schltr. (China, Japan, Korea, Soviet Union, Sikkim) Inperfeetly known species: 10) N. ussuriensis (Kom. et Nevski) S6o (Soviet Union) Thus, the subtribe Neottiinae are composed of four genera, namely, Diplandrorchis, Archineottia, Neottia and Listera. The new genus Archineottia, as one of the most primitive genera in the family, is of great interest from a phylogenetic point of view. It shows dose similarity to Diplandrorchis and Neottia in habit, but sharply distinct from them in column structure. These genera, as indicated By some authors, also show affinity in some respects with the subtribe Limodorinae, especially to Tangtsinia and Sinorchis, the other two quite primitive genera in the family. There is, indeed, a great need of further study of these interesting or relic genera and this, I think, would go a long way towards solving the problems concerning the origin ofthe Orchidaceae.     

Galeottiella hintoniorum,a new epiphytic species of Spiranthinae (Orchidaceae) from Nuevo León,Mexico

A new species of Spiranthinae from Mexico,Galeottiella hintoniorum, is described and illustrated. It is placed in the genusGaleottiella because of its lip and column structure and its herbaceous, cauline bracts and becauseGaleottiella is the oldest genus in the subtribe that can accommodate it. This new species is distinguished from other members of the genus by its epiphytic habit, small stature, and few-flowered inflorescences.     

Die GattungTeutonica Schröder 1991 (Gastropoda) aus dem Dogger Deutschlands und Nordwestpolens

Up to now the genusTeutonica has only been known by its type species. Four species and two subspecies are related to it herein; two species and one subspecies are new:T. verrucosa, T. procera andT. gramanni nodosa. Zygopleura rectecostata Walther is based on poorly preserved juvenile shells of aTeutonica species — therefore its specific identity will remain doubtful while its generic placement is clear. The genusTeutonica is known from the Bajocian and Bathonian. It was formerly related to the families Cerithiopsidae or Zygopleuridae. Here the genus is placed with the Polygyrinidae becausePolygyrina andTeutonica are very similar regarding teleoconch shape, course of the growth lines, and the protoconch shape.     

Cytotaxonomy of the monopodial orchids of the African and Malagasy regions

The three subtribes which are recognized within the tribe Vandeae are represented in the tropical African and Malagasy regions. All taxa of the Vandeae have a monopodial growth habit. The first subtribe, Sarcanthinae, is mainly Asian-Australasian, but a few of its species occur in Madagascar and in Africa. The other two subtribes. Angraecinae and Aerangidinae, are both represented in the latter two regions. The Angraccinae is characterized by the presence of a short rostellum, but this is elongated in the Aerangidinae. According to earlier authors there is a correlation between presence of the short rostellum and a basic chromosome number of x=19 in the Angraecinae, and between the presence of an elongated rostellum and a basic number of x=25 in the Aerangidinae. The results presented in this paper are placed in perspective with the chromosome numbers recorded by other authors. From the resulting chromosome number survey it appears that only part of the Angraecinae (Aeranthes, several species of Angraecum, Cryptopus and Jumellea) have a basic number of x=19; some members of the Angraecinae (other species of Angraecum) were found to have a basic number of x=21, 24 and 25. The Aerangidinae is not characterized by a single basic number of x=25 but by a series ranging from x=23 to x=27, of which x=23, 24 and 25 are the most frequent. The genus Calyptrochilum, although having a distinetly elongated rostellum, is characterized by a basic number of x=19 and its position within the Aerangidinae may therefore be questioned. The present evidence suggests that too much weight has been attributed to a single character, i.e. the shape of the rostellum, in distinguishing the two subtribes. As there appear to be two groups according to basic number in Angraecum, it appears questionable whether Angraecum, as presently conceived, is a ‘natural’ genus. Further chromosomal and other taxonomic evidence is needed to substantiate the challenge to the present views in respect of Angraecum. Taxa with x=19 appear to be frequent in Madagascar and the other islands in the Indian Ocean, whereas taxa with x=21 to 27 mainly occur on the African continent. The predominance of x=19 in the Malagasy flora suggests a link with the monopodial taxa of the Asian and Australasian floras, which are exclusively based on x=19.     

Kroemmelbeinia n. g., eine neue Ostracoden-Gattung aus dem marinen oberpliozän der Insel Kos (Griechenland)

Among the cytherine ostracodes possessing caudal process a new genusKroemmelbeinia is defined by its hinge-element. In its habitus, and its structure particularly the punctate surface and the inner lamella the new genusKroemmelbeinia resembles the genusMicrocytherura G. W. Müller, but which possesses smaller valves. The characteristic hinge-elementsof Kroemmelbeinia are: both terminal teeth in the left valve crenulate, interior with 5–6 terminal teeth in the left valve crenulate, interior with 5–6 toothlets, and posterior with 6–7 connected by a narrow and finely crenulate groove. By this hinge-constructionKroemmelbeinia differs fromMicrocytherura (Tetracytherura) Ruggieri 1952 and also from other genera(Cytheropteron, Perissocytheridea) of similar outline.     

Zur Nomenklatur der Gattungen Porochara Mädler 1955 (syn. Musacchiella Feist & Grambast-Fessard 1984) undFeistiella n. gen. (Charophyta)

The basal plate of the genusPorochara MäDLER 1955 (Porocharaceae, Charophyta) was proved to be divided into two parts by examining its type species. ThusMusacchiella Feist & Grambast-Fessard 1984 is a younger synonym ofPorochara. The genusFeistiella n. gen. is established for those species with undivided basal plates and it is described with the type speciesFeistiella bijuescensis n. sp. Six other species are attributed to this new genus. The relation between a fan shaped internal structure of the spiral cells and a brackish environment is discussed.     

Echinococcus granulosus: secretory activity of the rostellum of the adult cestode in situ in the dog.

Secretary activities associated with the rostellum of adult Echinococcus granulosus were studied using histological, histochemical, and ultrastructural techniques, following rapid fixation of the cestodes in situ in the small intestine of the anaesthetised dog. Studies concentrated on the host-parasite interface from 30 to 35 days postinfection. At this time, contraction of the muscular rostellar pad appeared to be associated with extension of the apical rostellum into a crypt of Lieberkühn. Crypt invasion by the apical rostellum coincided with morphological changes and secretory activity in a group of modified tegumental cells, previously referred to as the rostellar gland. Secretory material, a cystine-rich protein, was observed in the nuclei and cytoplasm of the rostellar gland cells. Release of this material into the interface was seen only following crypt invasion by the apical rostellum. Although the mechanism of release is not clear, it may be analagous to holocrine secretory mechanisms, since apparent degeneration of the rostellar gland region was associated with secretion. Possible functional activities of the secretion associated with hook formation, nutrition, regulation, adhesion, and protection are discussed.     

Hoeverella krauseae gen. et sp. nov., an unusual uniserial cheilostome bryozoan from the campanian of hannover

Hoeverellakrauseae gen. et sp. nov. is a peculiar runner-like anascan cheilostome bryozoan known from a single well-preserved specimen encrusting a belemnite guard. The colony comprises about 60 zooids, each of fusiform/pyriform shape and having a small “opesia” within which is situated an enigmatic ring structure. Several interpretations are possible for the ring structure: “regeneration”, closure plate, foreign organism inhabiting the zooecium, or socket of articulation for an erect branch or anAetea- like erect distal tube. Unusually for a runner-like bryozoan only one branch ramification occurs in the entire colony. The systematic position ofHoeverella is uncertain; however, it may be related to the electrid genusHerpetopora.     

Neubeschreibung vonCoelacanthus granulatus Agassiz (Actinistia,Pisces) aus dem Kupferschiefer von Richelsdorf (Perm,W.-Deutschland)

A revision of the genusCoelacanthus is made with special regard to the improved knowledge of the shape of its skull. A close relationship toLatimeria is found. A reorganization of the family of Coelacanthidae is proposed.     

Syllis onkylochaeta sp. n., ein korallenfressender Polychaet (Syllidae) aus dem Korallenaquarium des Löbbecke-Museums

A new species of the genusSyllis is described feeding on a colony of corals of the genusXenia (Xeniidae, Alcyonaria) in the coral aquarium of the Löbbecke Museum Düsseldorf. The origin of the corals is very probably Bali (Indonesia).     

Zur taxonomischen Gliederung der Familie Porocharaceae (Charophyta)

A revision of the charophyte family Porocharaceae Grambast is given, previously unstudied from the Keuper (Late Triassic) of Germany. The Porocharaceae were divided into three subfamilies. Two of them (Porocharoideae Grambast and Stellatocharoideae Grambast) are conserved; the third (Cuneatocharoideae Wang & Huang) is rejected. The diagnosis of the Stellatocharoideae is emendated. All genera with neck-like or conical apex are now included in this family, that means not only the genera of the rejected subfamily Cuneatocharoideae (Cuneatochara, Latochara, Stenochara), but also the genusStomochara, previously placed in the Porocharoideae. Only three genera (Porochara, Feistiella and the new genusKozurella n. gen.) are now attributed to the Porocharoideae, a subfamily characterized by a flat apex. The genusAuerbachichara Kiselevsky & Saidakovsky is a synonym toStomochara Grambast, the genusVladimiriella Saidakovsky toPorochara MÄDLER. Two additional species ofVladimiriella (V.decora SAIDAKOVSKY andV. karpinskyi Demin are assigned toStenochara Grambast on the basis of their apex-morphology. A new species,Cuneatochara württembergensis n. sp. is described from the Lower Keuper of Southern Germany.     

Lectins from the genusArtocarpus

The lectins from the seeds of two species of the genusArtocarpus (A. integrifolia L. andA. incisa L.) were isolated by affinity chromatography on an AB (+) human stoma column, and compared by physicochemical and immunochemical methods. Although with marked differences in the hemagglutinating activity, the elution pattern of the albummic and globulinic fractions from both seeds were comparable by affinity chromatography on a human-stroma column. The two isolectin families presented many similarities. All the lectins presented the same subunit pattern by SDS-polyacrylamide gel electrpphoresia, were recognised by both rabbit antisera prepared against the crude extracts from the two seeds, and presented fused rockets when electrophoresed in agarose gel containing one or the other antiserum.     

Meekella-Arten aus dem Perm der Karawanken und ihre Lebensweise

The morphology and the mode of life of species of the genusMeekella from the Karawanken is described. All species with high conical pedicle valve and very high interarea were attached by the beak either to the remains of organisms or to the solid sea floor. The smallMeekella depressa seems to have been unattached.Meekella crinicapiens was attached to a crinoid column with its transversal axis parallel to the long axis of the column.     

Drei neue Polychaeten-Arten der Familien Polynoidae und Syllidae von Neu-Kaledonien,assoziiert mit einer verkalkten Hydrozoe

Three new species are described:Lagisca zibrowii (Polynoidae) andProcerastea hydrozoicola andP. parasimpliseta (Syllidae), living in association with a calcified hydrozoan, probably of the genusPseudosolanderia (Rosalindidae). The genusParaprocerastea is synonymized withProcerastea.