Coccophagus funiculatus Myartseva sp. nov. (Hymenoptera: Aphelinidae), reared from the soft scale genus Toumeyella (Hemiptera: Coccidae), is described, and the aphelinid species associated with Toumeyella species in the New World are discussed and compared.
The world fauna of the soft scale genus Toumeyella Cockerell (Hemiptera: Coccidae) includes 17 species (Kondo & González 2014). Toumeyella is widely distributed in the New World with most species described from the USA (Kondo & Pellizzari 2011) (Table 1). In Mexico, 6 species are known: T. erythrinae Kondo & Williams, T. fontanai Kondo & Pellizzari, T. martinezi Kondo & González, T. mirabilis (Cockerell), T. parvicornis (Cockerell), and T. sallei (Signoret) (Kondo & Pellizzari 2011; Kondo & González 2014).
Checklist of Toumeyella parasitoids in the New World, and their global distribution (after Noyes 2014).
Most Toumeyella species are oligophagous. Five Mexican Toumeyella species have been collected on species in the plant families Fabaceae, Rosaceae, and Pinaceae, and T. martinezi occurs on “garambullo” cactus Myrtillocactus geometrizans (Mart.) (Cactaceae) (Kondo & González 2014). This cactus is widely distributed in xerophyllic habitats in Mexico, but in the town of Huichapan (State of Hidalgo, Mexico), populations are declining due to damage by T. martinezi. Three hymenopteran species of endoparasitods are associated with Toumeyella species in this area: Mexidalgus toumeyellus Myartseva and Coccophagus ruizi Myartseva & Ruiz (Aphelinidae), and Metaphycus sp. (Encyrtidae) (Martínez 2015).
Toumeyella species and their parasitoids in the Neotropical and Nearctic regions.
Four species of Aphelinidae have been reported from T. parvicornis, a scale that can cause severe decline of Pinus species. Coccophagus albicoxa Howard, C. immaculatus Howard and C. quaestor Girault (Aphelinidae) are primary parasitoids; an Aphytis species (Aphelinidae) was reported from this host, but the record is considered erroneous because all other Aphytis species parasitize armored scales (Diaspididae) (Malumphy et al. 2012).
Coccophagus quaestor was described from Mexico and has been reported in Canada, El Salvador, Peru, and the USA; C. immaculatus was described from the USA and has been reported in Chile; and C. albicoxa was described from the USA and is also known to occur in Panama (Noyes 2014). See Table 2 for a detailed listing of Toumeyella species and their parasitoids in the Neotropical and Nearctic regions.
Coccophagus Westwood, with 259 species, is the second most speciose genus in Aphelinidae after Encarsia Förster; 30 species of Coccophagus occur in Mexico (Myartseva et al. 2012). Coccophagus funiculatus sp. nov. was reared from Toumeyella sp. from the State of Puebla, Mexico, and is described in this article.
Species of both Mexidalgus and Coccophagus parasitize Toumeyella scales in Mexico. According to Hayat (1998), Mexidalgus is placed in the subfamily Coccophaginae based on the following characteristics: antennal flagellum with 5 to 6 segments, pale lines and sutures on the head, forewing without a linea calva. This genus possesses characters that occur in the genera Coccophagus and Coccobius Ratzeburg (Myartseva et al. 2014), but is distinguished from all other genera of Coccophaginae by the following combination of characters: 7-segmented female antennae, 2-segmented club; mandible with 2 short teeth and 1 truncation, apical margin with small serrations; 3rd valvula of ovipositor absent (possibly 2nd valvifer and 3rd valvula are very closely fused); 7-segmented male antennae, 2-segmented club, elongated apical segment of club; reduced mandible, without teeth, about half as long as the female mandible; genitalia shorter than the mid tibia; 3rd to 6th gastral sternites with an area of large pegs located in the middle.
Differences between 3 closely related species of Coccophagus.
Coccophagus funiculatus sp. nov. is the 2nd species in Mexico reared from species in the genus Toumeyella. The new species belongs to a group that includes C. mexicanus Girault and C. albicoxa and is characterized by having pale hind coxae and a densely setose scutellum; see Table 3 for a comparison of C. funiculatus sp. nov. with C. mexicanus and C. albicoxa.
Materials and Methods
Adults and larvae of Toumeyella sp. were collected on “tejocote” in May 2014 in Chiautcingo, State of Puebla, Mexico. Parasitic wasps of the families Aphelinidae and Encyrtidae (Chalcidoidea) were reared in the laboratory from this material. Some specimens were used for preparing microslides, following Noyes (1982). Morphological characters were examined using a Leica GME compound microscope. Compere (1931), Woolley (1997), Myartseva (2006), and Trjapitzin et al. (2008) were used for identification. Other specimens were preserved on small rectangular cards. Type material was preserved in UCRC (Research Entomological Museum, University of California, Riverside, California), BMNH (The Natural History Museum, London, United Kingdom), CNIN (Colección Nacional de Insectos, Instituto de Biología, Universidad Nacional Autónoma de México), CEAM (Colección de Insectos del Colegio de Postgraduados, Campus Montecillo, Texcoco, Estado de México), and UAT (Insects Museum, Universidad Autónoma de Tamaulipas, Ciudad Victoria, Mexico).
Coccophagus funiculatus Myartseva, sp. nov.
HOLOTYPE: female, MEXICO, Puebla, Municipio de Chiautcingo, San Nicolás Zecalacoayan, 19.199167°N, 98.488333°W, 2,460 m, 8-V-2014, ex Toumeyella sp. on Crataegus mexicana (col. R. C. Hernández-De la Cruz). Paratypes: same data as holotype, 14 females, and 1 female collected on 1-VII-2014, all point-mounted, and 3 additional females on slides. Holotype and 4 paratypes preserved at UCRC, 4 paratypes at BMNH, 4 paratypes at CNIN, 3 paratypes at CEAM, and 3 paratypes on slides at UAT.
Length: 1.75–2.1 mm. Coloration: Head black; scape and antennal pedicel dark yellow, flagellum dark brown. Mesosoma black, tegulae whitish-yellow with dark apical margin, scutellum whitish-yellow on apical 1/2–2/3, with black setae; forewings hyaline with brown venation. Propodeum whitish-yellow laterally, black medially. Legs black, except the following, which are yellow: apices of fore and mid-femur, fore and mid-tibiae ventrally and on apical half, apices of hind tibiae; all tarsi whitish, without infuscate apical segment; white hind coxae and trochanters; gaster bright black.
Body: (Figs. 1 and 2; female, lateral view and dorsal view of mesoscutum). Head slightly wider than mesosoma, slightly wider than height. Frontovertex about 0.5 times as wide as width of head. Ocelli obtuse triangle. Eyes finely setose, 1.5 times as wide as cheeks. Mandible (Fig. 3) with 2 ventral teeth only, slightly developed, with wide truncation. Antenna (Fig. 4) arising at level of lower margin of eye. Radicle short, slightly longer than wide (5:4). Scape long, 6.0 times as long as wide. Pedicel 1.4 times as long as wide. First funicular segment longest, 3.0–3.3 times as long as wide. Second and 3rd segments subequal in length and width, each about 2.0 times as long as wide. Club shorter than 3rd and 2nd funicular segments combined. First segment of club about 1.3 times as long as wide and slightly wider than funicle; 2nd segment slightly wider than long (3:4), apical segment subequal in length and width. Flagellar segments with numerous longitudinal sensilla, situated in rows of 4, 3, 3, 2, 1, 1, respectively, from 1st to 6th segments (Figs. 7 and 8). Mid-lobe of mesoscutum with many scattered setae. Scutellum with many short setae and 2 pairs of long, strong bristles, apical pair longer. Forewing 2.4 times as long as wide, with very short marginal fringe. Submarginal vein with 7 long setae on anterior margin. Marginal vein longer than submarginal vein. Stigmal and post-marginal veins as in Fig. 5. Mid-tibial spur (Fig. 6) long and slightly shorter than basitarsus; basitarsus with a row of peg-like setae. Dorsal margin of hind tibia with a row of stout, suberect setae. Ovipositor slightly exerted, 1.7 times as long as mid-tibia; 3rd valvula about 0.3 times as long as 2nd.
We would like to acknowledge the financial support to the PRODEP Project “Taxonomía y ecología de fauna y micobiota en comunidades forestales y cultivos de México” and the Autonomous University of the State of Tamaulipas (UAT) for the realization of this work. We thank M. Luiza Collin, who helped with the English style, and the Co-editor Ian Stocks of Florida Entomologist for improving this article in several ways.