anal. La paroi d'un sac porte plus de 400 unites giandulaires tuberculees. La presence ... Each gland forms a glandular pouch bearing more than 400 tubercular ...
Ann. Soc. £momoL Fr. (N.S.). 2000. 36 (2) :
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142.
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VOLUMINOUS PAIRED GLANDS IN THE TENTH ABDOMINAL SEGMENT IN THE FEMALES OF THE GENUS CLADODlPTERA SPINOLA (HEMIPTERA: FULGOROMORPHA : DICTYOPHARIDAE)
J
Thierry BOUROOlN Museum national d'Histoire naturelle, Laboratoire d'Entomologie & UPR£S-A 8043 du CNRS, 45 rue Buffon. F-7500S Paris. France. [e-mail: bourgoil\@cimrs l.mnhn.frJ
Resume. - Presen ce de yolumineuses gla ndes paires dans le dixieme segment abdomin a l chez les ft'me lles du ge nre Cladodiptera Spinola ( Hemiptera : Fulgoromorpba : I>iclyopharidae). - On signale pour la premi~re fois la presence d'une paire de glandes volu mineuses (500 llfIl) s'ouVf:lm 11. la face ventrale du dixieme segment abdominal des femelles du genre Cladodiptera (Fulgoromorpha. Dictyopharidae). Les glandes s'ouvrent sur rexterieur par deux orifices. separes par une dent cmiculaire dont In position et la forme v3rient suivant les es~ces. Chaque glande est constilUc d'un sac glandulaire profondement invaginc it l'interieur du tube anal. La paroi d'un sac porte plus de 400 unites giandulaires tuberculees. La presence de ces glandes, qui n' existent pas chez les genres apparentes. repn!sente vraisemblablement une synapomorphie pour Ies esptces du genre Cladodiplera. Le rOle de ces glandes reste inconnu mais cUes pourraient li~rer des mc!di3teurs chimiques tel que des phi!romones. Abstract. - A pair of vo luminous glandular pouches located on the ventral side of the tenth abdominal segment is described for the first ti me. The glands arc present in the female of the genus Cladodiptera (Hemiptera, Fulgoromorph a. Oictyopharidae). Their openings are separated by a cuticular process which shows some specific variation in its location and shape. Each gland forms a glandular pouch bearing more than 400 tubercular glandular units. The presence of these glands might represent a synapomorphy for the genus 3S they arc absent in related taxa. Their role is unknown, but they may release chemical mediators as a pheromone.
]
The purpose o f this note is to d escribe a highly in tegrated complex o f tegumentary glands present in females of th e Dic lyopharid ae gen us C/(ldodiplera. Following NOIROT and Q UENNEDEY (1991), the term gland is used here in the sense ofa complex assemblage of g landular units integrated in a pair o f m e mbranous pouches and associated to a median c uti cul ar tooth separating the two openings. Such a voluminous and complex g landular organ never appears to have been previous ly described in any fulgoromorph. This new character represents a probable synapomorphy for the genus and allows som e taxonomic discussion for this taxa.
Materials and methods The glands were examined in dried specimens of Cladodiprera m(J.crophrholnw Spinola, 1839, and otherundetennined species of this genus. After a 10% KOH bath (raised to boiling for 10 mn)and an endoManuscrit accepte le 3-V-2000.
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cuticular staining with chlorazol black E, the specimens were dissected in distilled water 10 remove the anal tube. [\ was cleaned in an ultrasonic bath of 70% alcohol and dehydrated through increasing concentrations of alcohol, critical poin! dried and coated with a 65-70 Ilffi film of gold-palladium. They were examined with a Jeal ISM 840 scanning electron microscope (Service de Microscopie electroniq ue, MNHN, Paris).
DESCRIPTION The tenth and eleventh segments ill C/adodiplera females form an elongated cylindrical tube - or anal tube - dorsally above the female genitalia. The glands, which belong to the
tenth segment, are internal and open ventratly on the anal tube. They fonn a pair of elongated pouches resting on the ventral wall of the anal tube and opening individually on each side of a sagittal more or less acute process (fig. l A). Each pouch is generally as long as the two thirds of the anal tube. The place of the process varies from a median to a sub-distal position according to the species studied. Scale-like cuticular structures cover the whole surface of this process (tig. I B). In C. maclVphthalllw. they are 1O-15).1m long, basally wider, acute and seta-like distally. They are slanted on each other and overlap partially. AboUl 10 large setae of 80-100 J.UTI long; slightly ridged, flank the process. Inside the anal tube, each glandular pouch is sac-like, slightly dorso-ventrally flattened, 400-500 Ilm long for 100).lm wide (figs le, 2). The internal wall of the pouches presents about 400 tubercles (figs 10,4) of 8-9 Ilm wide, very finely ridged longitudinally (fig . 4, LR). Each tubercle bears a small thick ring-like structure (fig. 4, RS) of 7 ).Im diameter for 2).1m high. The tubercles are somewhat arranged in rows and united by thin cuticular crests (figs ID; 4, er). The center of each thick ring-like structure bears a wide aperture of 2.5 Ilm diameter limited interiorly by a circular ridge (fig. 4, eR). The external wall of the pouches (in the lumen inside the sac) shows a highly ridged surface covered with numerous conical cuticular processes (figs [E. 4: CCP). Each conical cuticular process corresponds to an internal thick ring-like structure (fig. 3). No pore neither canal was observed at higher magnification by optieal (x 1400) or scanning (x 25(0) microscopy. DISCUSSION Possible role. - As such integrated complex glandular structures have never been described in any fulgoromorphs or even in any insect tenth abdominal segment, and without any ultrastructural examination, the glandular nature of these structures can only be suggested here. However, it is likely that each ring-like structure corresponds to the short conductive duct of several tegumentary gland cells, forming scattered gland units. Each glandular unit opens externally through the conical cuticular process, which may be constituted with modified cuticle to allow secretion to pass through as no pore could be observed . Secretion products should be accumulated in the paired pouches before being released outside. The specialised scale like strucrures which cover the surface of the medioventral process might correspond to a special evaporative area. Tegumentary glands are poorly studied in Fulgoromorpha and are mainly known by their most obvious physiological manifestations: waxy powdering or wax filaments (BUGNION & POPOFF, 1907; BUGN!ON, 1908; POPE, 1985, BOURGOIN, 1997, SFORZA et al., 1999). Their role is generally unknown but in Fulgoridae, waxy secretions are thought to be a protection against predators and parasites (MASON ef al., 1989). This is obviously nor the case here as these clearly cannot be wax glands: no pore is observed and secretion is delivered in a membranous pouch deeply invaginated in the anal tube. However some of these glands are not necessarily only wax productive but may release chemical mediators as already known in other Hemiptera taxa such as Stemorrhyncha (ALDRICH, 1996) or Heteroptera (ALDRlCH, 1988). In Fulgoromorpha such glands should represent an important unstudied cOlllmunication system which, linked or not to sound communication now well known (CLARIDGE & DE VRUER, 1994), might direct much of their behaviour:
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en-
- lands in the genus Cladiptera
ants-tettigometrids trophobiosis behaviour as suggested by BOURGOIN (1986). these glands are scattered singly or in small groups on the tegument, sometimes in special "glandular areas" (BOURGOIN, 1997). They may be present in one or the two ~_g. the "collaretted glands" are only known in male tettigometrids (BOURGOIN, 1986). The role of these very particular and voluminous paired glands in Cladodiptera remains Ll. Present only in females , this system suggests rather a pheromonal role, while some egg protection after laying should also be investigated (HOGUE et al., 1989). structural and behavioural studies are needed to confirm any of these hypotheses.
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Fig. I. paired glands of Cladodiptera macrophthabna Spinola. - A, openings of the paired glands at the base of the ventral wall of the anal tube. - B, external view of the sagittal acute process showing the scale-like cuticular structures tapering the process. - C, paired glandular pouches, internal wall. -D, tubercles arranged in rows on cuticular crests on the internal wall. -E, conical cuticular processes on the external wall inside the pouches.
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Abdomim,/ glands in the genu.I' Cladiplem
Systematic. - So far, such paired glands have never been observed in Fulgoromorpha, and interestingly they are absent in other Cladodiptera related taxa. This allows some further systematic remarks for this genus. Tn 1946, METCALF grouped six genera together with Cladodiptera in the Dichopterini : Protachilus Fennah, Diacira Walker, Dichoptera Spinola, Pibrocha Kirkaldy, Awaramada Distant, Dorysarfhrus Puton, and Dari(iIJa Walker. The last one was transferred to the Cicadelloidea Coelidiinae as a synonym of Coelidia by METCALF (1964). In 1979, EMEUANOV proposed a new classification of the Dictyopharidae-Fulgoridae taxa and two genera : Dorysarlhrus and Dichoptera, were transferred to the Fulgoridae in new monogeneric subfamilies: Dorysarthrinae and Dichopterinae. None of the other closer related taxa and particularly Protachilus and Diacira grouped with Cladodiptera in the Cladodipterini by M ETCALF ( 1946) shows such an anal gland.
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Fig. 4. internal. c:
