Acta Zoologica 23. (1977)

1977 / 3-4. szám - STYS, P.: Revision of Symphylax (Heteroptera: Colobathristidae)

428 p. Sty s also the distribution of the genus is surveyed and the diagnostic value of individual characters is discussed. The 5th instar nymph of Symphylax picticollis lias been studied; it is described and illustrated, and particularly its bizarre and among Heteroptera uniquely modified orifices of the first pair of abdominal glands are discussed. To my knowledge it is a first adequate description of a Colohathristid nymph. Acknowledgements. I am greatly indebted to Dr. A. Soós for continuous help during my work in the collections of Természettudományi Múzeum Adattára (TMA throughout the paper), Budapest, and for his kind permission to borrow all Horvath’s specimens of Symphylax. Dr. M. S. K. Ghauri (Commonwealth Institute of Entomology, London) generously provided various information, particularly his unpublished data on female terminalia of Symphylax musiphthora. My thanks are due to Dr. U. Göllner-Scheiding (Zoologisches Museum, Hum­boldt-Universität, Berlin) and Dr. W. Wittmer (Naturhistorisches Museum, Basel) for the loan of all available Symphylax material in their charge. Dr. D. Guiglia (Museo Civico di Storia Naturale, Genoa) kindly informed me about the prohibitive regulations concerning loans from the Genoese museum. Symphylax Horváth Symphylax Horváth, 1904: 118 (keyed), 142- 143 (descr.); Ghauri, 1968: 82 — 84 (redescr.). Type-species: Symphylax picticollis Horváth, 1904; monobasic (origi­nally also two varieties included). Horváth (1904) described and keyed the genus; however, his key charac­ters are no more reliable for its identification. Since Ghauri (1968) provided an exhaustive morphological generic diagnosis, only those generic characters are below listed by the combination of which Symphylax is immediately dis­tinguishable from the other genera of Colobathristidae. Extremities very long; apex of corium with a triangular cell; eyes only posteriorly stylate; infraocular carinae absent; vertex with a single longitudinal furrow (anteriorly with an indication of branching) extending far in front of ocelli; distance ocellus — eye about 1.5—2.5 times as long as interocellar dis­tance; fourth antennal segment without white basal ring; labium reaching at least apices of mesocoxae; pronotum mutic, its callar region not gibbous; scutellum with an erect spine; ventral abdominal sulcus 3—4 retained; ventrite 4 longer than ventrites 5—7 together; total length not exceeding 10 mm. Both Horváth (1904) and Ghauri (1968) characterized the fore femur of Symphylax as possessing only one anteapical spine. However, Bergroth (1910) already noted that in Symphylax sp. (here identified as S. confluens borneensis) also two spinules occur distad of the major spine. Actually, the ventral surface of the fore femur (between the anteapical spine and the apex of femur) in all individuals of Symphylax is provided with one or two (anterior and posterior) fields of small rasp-like structures, sometimes occurring also along the distal edge of the spine. Often one to five of these structures are enlarged to form distinct spinules; their development is individually highly variable, but they are best developed in S. confluens where usually two large spinules occur. Similar, but finer, rasp-like structures also occur on the opposing side of the base of fore tibia. This device is equally developed in males and females and may function as an organ enabling the bugs to grasp the petioles of leaves or grass stems, or it may be a cleaning organ for the antenna, functionally replacing the poorly developed apicitibial comb. Distribution. The range of Symphylax is typically Indo-Malayan (in Acta Zoologica Academiae Scientiarum Hungaricae 23, 1977