Palabras clave: Hipógeas, Coccoidea, órgano genital, descripciones.

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1 Boletín del Museo de Entomología de la Universidad del Valle 15(1):7-11, SECOND TIME SYNONYMY OF Rhizoecus perprocerus De Lotto, 1961, WITH Rhizoecus graminis (Hambleton, 1946) (HEMIPTERA: RHIZOECIDAE). Andrea Amalia Ramos-Portilla Instituto Colombiano Agropecuario ICA; Grupo Sistemática de Insectos Agronomía (SIA). Museo Entomológico UNAB; Facultad de Ciencias Agrarias, Universidad Nacional de Colombia, Edificio 500 Lab Bogotá D.C. andrea.ramos@ica.gov.co, aramosa@unal.edu.co, andreaamaliaramos@gmail.com. RESUMEN Cox (1978) sinonimizó Rhizoecus perprocerus De Lotto, 1961 con Morrisonella graminis Hambleton, 1946 (conocida ahora como Rhizoecus graminis), basada en el estudio comparativo de la morfología de la hembra adulta. Después, Kozár & Konczné Benedicty (2007) consideraron la hipótesis de Cox (1978) como una sinonimia incorrecta. En el presente estudio se revisa nuevamente la morfología externa de las hembras adultas del material tipo de ambas especies y se discute el valor taxonómico de la longitud y forma del órgano genital, el número y distribución de los ductos tritubulares abdominales ventrales y el tamaño y forma de los sensorios antenales. R. perprocerus es sinonimizado con R. graminis una vez más. Palabras clave: Hipógeas, Coccoidea, órgano genital, descripciones. SUMMARY Previously, Cox (1978) synonymized Rhizoecus perprocerus De Lotto, 1961 with Morrisonella graminis Hambleton, 1946 (now known as Rhizoecus graminis), based on a morphological comparative study of the adult female. Later, Kozár & Konczné Benedicty (2007) considered the synonymy by Cox (1978) as an incorrect synonymy. In the present study, R. perprocerus is once more synonymized with R. graminis after reexamination of the morphology of the type material of R. graminis and R. perprocerus. The taxonomic value of the shape and length of the genitalia, the distribution of ventral tritubular ducts on the abdomen, and the size of the clavate sensory setae in the antennae are discussed. Key words: hypogeic, Coccoidea, genitalia, descriptions. INTRODUCTION Rhizoecus graminis was originally described by Hambleton (1946) in the genus Morrisonella Hambleton, 1946, based on the length and shape of apical segment of the antenna, absence of circuli, and presence, number, and distribution of multilocular disc pores. This species has been found in roots of Convolvulaceae: Dichondra repens, and Poaceae: Agrostis tenuis, Festuca rubra, Lolium perenne, and reported from different regions, including the Afrotropical: South Africa, and Tanzania; Australasian: New Zealand; and Nearctic: The United States

2 8 Ramos-Portilla, Second time synonymy of Rhizoecus perprocerus with R. graminis of America (Ben-Dov et al. 2014). Rhizoecus perprocerus was described by De Lotto (1961) separating it from R. immsi James, 1935, by the absence of circuli and the presence of a small sclerotized area near the setae on the cerarii of the anal lobe. De Lotto studied four specimens, collected on roots of an unknown host, from South Africa (De Lotto 1961). Therefore, the species is only known from the type material (Ben-Dov et al. 2014). Cox (1978), synonymized R. perprocerus with R. graminis. Her judgment was based on the presence of a cephalic plate and a sclerotized area on the anal lobes in the studied specimens. These traits were considered lacking by De Lotto (1961). Cox (1978) indicated that the observation of these traits is highly dependent on slide-mounting techniques, because the excessive heating with potassium hydroxide solution would have removed them. Almost thirty years after Cox s work, Kozár & Konczné Benedicty (2007) studied the holotype of R. perprocerus and revived the name based on the presence of an extra submedian row of ventral tritubular ducts on the abdomen, the size of clavate sensory setae and length of the genital organ. They redescribed R. graminis and R. perprocerus as having different shapes of genitalia (Kozár & Konczné Benedicty 2007). After studying the variation in the number and distribution of rows of ventral tritubular ducts on the abdomen in a number of specimens, including type material of both species, it was found that this character state is variable. Furthermore, the shape of the genitalia in both species are very similar. MATERIALS AND METHODS Measurements and illustrations were made using the image analysis program Axion Vision Carl Zeiss on a phasecontrast Carl Zeiss microscope. The number and distribution of tritubular ducts on the venter of the abdominal segments, length and shape of the genitalia and the length and shape of the proximal clavate sensory setae on the antenna were studied. Illustrations of the genitalia were based on images taken from the type material of R. perprocerus. All material studied is deposited at the USNM, National Museum of Natural History, Entomological Collection, Washington, DC, USA (Coccoidea collection held at the US Department of Agriculture, Beltsville, Maryland). Terminology used. In the literature, there is no agreement for the name assigned to the three-ducted cuticular structures, which are present in all of the species belonging to the genus Rhizoecus. Some names include: tritubular ceror (Hambleton 1946, Cox 1978, and Hodgson & Williams 2008); tritubular pores (McKenzie 1967, Williams 1985, Williams & Granara de Willink 1992, and Kozár & Konczné Benedicty 2007). On the other hand, Ferris (1953) and De Lotto (1961) call them tritubular ducts. Herein the term tritubular ducts is used following Foldi (1983, 1991). Accordingly, the three very distinctive basic units of cuticular structures, transporting and discharging wax secretions, could be pores, ducts, and ductules. Pores are cuticular structures that cover

3 Boletín del Museo de Entomología de la Universidad del Valle 15(1):7-11, the wax gland and are specialized for the extrusion of the wax secretion; externally, they have either a simple or a loculate opening (loculus), generally with geometric arrangement. The pores are called simple, bi-, tri- quadriquinque- or multilocular pores depending on the number of loculi present. Ducts are cuticular tubules, cylindrical or flat, and invaginated into the body. Structurally, a duct always has an inner ductule which transports the secretion from the central glandular cell to the inner end of the duct. The distinction between a duct and a pore lies in the presence or absence of an inner ductule. Sometimes the inner ductule is very fragile and may often be destroyed during the preparation of the slide mounted specimen (Foldi 1991). Finally, the ductules are cuticular tubes, small, 0,2 1 µm in diameter and generally 1 4 µm long; they assure the direct transport of the secretion from the receptor ductule to the exterior. Material Examined. Rhizoecus graminis. Holotype. Adult : USA, California, Oakland, on roots of bentgrass. Essig Coll. 29 Jun Hambleton det. Paratypes. 11 adult : same data as holotype. Nontype material. 1 adult : USA, Colma, San Mateo, California, soil sample. 12 Dec C.S. Kochler Coll. Willey det. (USNM). Rhizoecus perprocerus. Paratype. 1 adult. South Africa, Hex River. July C.Y. Joubent Coll. De Lotto det. Non-type material. 2 adult : New Zealand, on roots grass. 18 Sep McKenzie coll. J.M. Johannesson det. 2 adult : New Zealand, Wellington Prov., 2 Aug M. Luxton coll. (USNM). RESULTS AND DISCUSSION Distribution of ventral tritubular ducts on the abdomen. There are two longitudinal rows of ventral tritubular ducts on the venter of the abdomen; a submarginal row and a lateral row between abdominal segments III to VII. In addition to the longitudinal rows, a variable number of tritubular ducts are present on the median area on the venter of abdominal segment VI, ranging between 0 4, with 1 being the most common in R. graminis (n=9). In R. perprocerus the submarginal and lateral rows of tritubular ducts on the venter of the abdomen are also present, with 0 2 (usually 0) tritubular ducts present on venter of abdominal segment VI, like specimens of R. graminis (n=5). This observation shows the variability of this character state. The influence of environmental factors on variation in the number of structures such as multilocular disc pores and tubular ducts was studied by Cox (1983). Length and shape of genitalia. Rhizoecus graminis and R. perprocerus have the same distinct shape of genitalia (Fig. 1A, C & E). The description of the genitalia given by Kozár & Konczné Benedicty (2007) for Rhizoecus perprocerus (Fig. 1B) and R. graminis (Fig. 1D) do not match the morphology of their respective type specimens. The shape of R. perprocerus and R. graminis are very similar if not identical (see Fig. 1 A & C); and the length of the genitalia in both species overlap, µ m (n=6) in R. graminis and 190 µ m (n=2) in R. perprocerus.

10 Ramos-Portilla, Second time synonymy of Rhizoecus perprocerus with R. graminis A B C D E Figure 1. A. Genitalia of Rhizoecus perprocerus (Paratype). B. Genitalia of R. perprocerus, as drawn by Kozár & Konczné Benedicty (2007).

Photos of genitalia (Fig. 1A & C) taken by A. Ramos. Length and shape of the proximal clavate sensory setae of antennae. The sensory setae of the antennae of R.

graminis is 19 22 µm (n=6), whereas the length is 19 21 µm in R. perprocerus (n=3), clearly overlapping. CONCLUSIONS Kozár & Konczné Benedicty (2007) revived R. perprocerus from its synonymy with R.

4 10 Ramos-Portilla, Second time synonymy of Rhizoecus perprocerus with R. graminis A B C D E Figure 1. A. Genitalia of Rhizoecus perprocerus (Paratype). B. Genitalia of R. perprocerus, as drawn by Kozár & Konczné Benedicty (2007). C. Genitalia of R. graminis (Holotype) D. Genitalia of R. graminis as drawn by Kozár & Konczné Benedicty (2007). E. Genitalia of Rhizoecus perprocerus (Paratype), original drawing. Photos of genitalia (Fig. 1A & C) taken by A. Ramos. Length and shape of the proximal clavate sensory setae of antennae. The sensory setae of the antennae of R. graminis are filiform (n=2) to slightly clavate (n=5). In R. perprocerus the shape of the sensory setae of the antennae is slightly clavate (n=5). The length of the sensory setae of the antennae in R. graminis is µm (n=6), whereas the length is µm in R. perprocerus (n=3), clearly overlapping. CONCLUSIONS Kozár & Konczné Benedicty (2007) revived R. perprocerus from its synonymy with R. graminis based on highly variable morphological character states. As shown above, the character states used to separate R. perprocerus and R. graminis overlap, thus there is no basis to consider R. perprocerus as a separate species. The observations in the present study added to the information provided Cox (1978) is enough evidence to consider R. perprocerus as a junior synonym of R. graminis. ACKNOWLEDGMENTS Many thanks to Dr. Douglass Miller, Mrs. Barbara Denno and Dr. Gary Miller (USNM) by the technical and personal support during the revision of the type material. To Dr. Penny Gullan and Dr. Takumasa Kondo for the revision of the manuscript and for you very useful comments. To Dr. Francisco Serna and to anonymous reviewers who helped improve this manuscript. Literature cited Ben-Dov, Y., D. R. Miller & G. A. P. Gibson ScaleNet. A data base of the scale insects of the world. (Acces-

5 Boletín del Museo de Entomología de la Universidad del Valle 15(1):7-11, sed 11/03/012). Cox, J.M Revision of the Rhizoecus species (Homoptera: Pseudococcidae) known from New Zealand. New Zealand Journal of Zoology 5: Cox, J.M An experimental study of morphological variation in mealybugs (Homoptera: Coccoidea: Pseudococcidae). Systematic Entomology 8: De Lotto, G New Pseudococcidae (Homoptera: Coccoidea) from Africa. Bulletin of the British Museum (Natural History) Entomology 10: Ferris, G.F Atlas of the Scale Insects of North America, v. 6. The Pseudococcidae (Part II). Stanford University Press, Palo Alto, California. 506 pp. Foldi, I Structure et fonctions des glandes tégumentaires de cochenilles Pseudococcines et de leurs sécrétions. [Structure and functions of the integumentary glands of mealybugs, Pseudococcidae, and of their secretion]. (In French; Summary In English). Annales de la Société Entomologique de France 19: Foldi, I The wax glands in scale insects: comparative ultrastructure, secretion, function and evolution(homoptera: Coccoidea). Annales de la Societe entomologique de France (N.S.) 27(2): Hambleton, E.J Studies of hypogeic mealybugs. Revista de Entomologia. Rio de Janeiro 17: Hodgson, C.J. & Williams, D.J A new record of a mealybug species (Hemiptera: Coccoidea: Pseudococcidae) from Tristan da Cunha and a new description of the species. (Summary in Italian). Bollettino di Zoologia Agraria e di Bachicoltura (Milano) 40(3): Kozár, F. & Konczné Benedicty, Z Rhizoecinae of the world. Plant Protection Institute, Hungarian Academy of Sciences, Budapest. 617 pp. McKenzie, H.L Mealybugs of California with taxonomy, biology, and control of North American species (Homoptera: Coccoidea: Pseudococcidae). University of California Press, Berkeley. 526 pp. Williams, D.J Hypogeic mealybugs of the genus Rhizoecus (Homoptera: Coccoidea) in India. Journal of Natural History 19: Recibido marzo 24, 2014, publicado agosto 25, 2014

First record of Ripersiella kelloggi Ehrhon and Cockerell (Hemiptera: Rhizoecidae) for the Neotropics, with a redescription of the adult female

University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Insecta Mundi Center for Systematic Entomology, Gainesville, Florida 2014 First record of Ripersiella kelloggi Ehrhon and