Aphanomerus rufescens Perkins, 1905

Popovici, Ovidiu Alin, Masner, Lubomír, Viciriuc, Mădălina, Pintilioaie, Alexandru, Notton, David G. & Talamas, Elijah, 2018, New distribution data for some charismatic tramp species of Platygastroidea (Hymenoptera), Zootaxa 4370 (1), pp. 1-22 : 10-16

Aphanomerus rufescens Perkins

http://bioguid.osu.edu/xbiod_concepts/12319 Figures 25–45 , 48

Aphanomerus rufescens PERKINS, 1905 : 202 (ORIGINAL DESCRIPTION); DODD 1914: 60 (DESCRIPTION); KIEFFER 1926: 136, 137 (DESCRIPTION, KEYED); VLUG 1995: 19 (CATALOGED, TYPE INFORMATION).

Material examined. NORTH AMERICA: USA, California, Los Angeles: 3♀ & 1♂, Los Feliz , 34.118°N, 118.284°W, alt. 220 m, 3–7.ix.2013, leg. Mark & Jane Pisano (MT; OPPC) ; 4♀ & 1♂, Silverlake , 34.093°N, 118.274°W, 31.viii–7.ix.2013, leg. W. Renwick (MT; OPPC) ; 1♀, University Park , 34.034°N, 118.281°W, alt. 63 m, 28.viii–4.ix.2013, leg. P. Hentschke (MT; OPPC) ; 2♀, University Park , 34.034°N, 118.281°W, alt. 63 m, 3– 10.xii.2014, leg. P. Hentschke (MT; OPPC) ; 3♀, University Park , 34.034°N, 118.281°W, alt. 63 m, 29.x–5.xi.2014, leg. P. Hentschke (MT; OPPC) ; 1♀, Glendale , 4–9.viii.2014, 34.149°N, 118.218°W, leg. Hoffman (MT; OPPC) ; 2♀, University Park , 34.034°N, 118.281°W, alt. 63 m, 3–10.ix.2014, leg. P. Hentschke (MT; OPPC) ; 1♀, Mid- Wilshire , 27.ix–4.x.2014, 34.058°N, 118.328°W, leg. P. Lombard (MT; OPPC) ; 1♀, Mid-Wilshire , 30.viii– 6.ix.2014, 34.058°N, 118.328°W, leg. P. Lombard (MT; OPPC) ; 1♂, Silverlake , 34.102°N, 118.257°W, 30.viii– 6.ix.2014, leg. J. Hogg (MT; OPPC) ; 1♂, Silverlake , 34.102°N, 118.257°W, 2–9.viii.2014, leg. J. Hogg (MT; OPPC) ; 1♀, Los Feliz , 34.116°N, 118.279°W, 29.vi–6.vii.2014, leg. J. Aaron & J. Koch (MT; OPPC) ; 1♀, Los Feliz , 34.112°N, 118.293°W, 1–8.viii.2014, leg. P. Louie (MT; OPPC) ; 3♀, Los Feliz , 34.116°N, 118.279°W, 2– 9.viii.2014, leg. J. Aaron & J. Koch (MT; OPPC) ; 1♀, Larchmont , 34.077°N, 118.32°W, 27.ix–4.x.2014, leg. K.T. Wiegman (MT; OPPC) ; 1♀, Mid-Wilshire , 34.058°N, 118.328°W, 1–9.xi.2014, leg. P. Lombard (MT; OPPC) ; 1♀, Mid-City , 34.047°N, 118.334°W, 27.ix–4.x.2014, leg. S. Oxborough (MT; OPPC) ; 1♀, Gardena , 33.876°N, 118.288°W, 29.xi–6.xii.2014, leg. B. Defibaugh (MT; OPPC) ; 1♀, Highland Park, 34.125°N, 118.189°W, 29.xi– 6.xii.2014, leg. C. Franco (MT; OPPC) ; 3♀ & 2♂, Silverlake , 34.093°N, 118.274°W, 27.ix–4.x.2014, leg. W. Renwick (MT; OPPC) ; 1♀, Silverlake , 34.093°N, 118.274°W, 30.viii–6.ix.2014, leg. W. Renwick (MT; OPPC) ; 2♀ & 1♂, University Park , 34.034°N, 118.281°W, alt. 63 m, 1–8.x.2014, leg. P. Hentschke (MT; OPPC) . 1♀, San Pedro, 3171 N. Gaffey Dr., Defense Fuel Support Point , coastal sage scrub, 24.iv–26.v.2002, leg. J. George (MT; CNCI) ; 1♂, Rancho Palos Verdes , 5.vii–2.viii.2003, leg. J. George (MT; CNCI) ; 1♀, Hawai’i, Kohala Forest Reserve, 20.0577°N, - 155.6339°W, 11–18.vii.2005, leg. Luc Leblanc (MT, CNCI).

AUSTRALIAN: AUSTRALIA: 1♀, Australian Capital Territory, Canberra, Nature Park, Black Mountain , Aranda Bushland , - 35.2648°S, 149.0846°E, 27–28.xi.2002, Eucalyptus forest, leg. George-Munro & Owen (MT; CNCI); 6♀ & ♂, Queensland, Brisbane Forest Park, - 27.4177°S, 152.8300°E, 30.xii.1997, leg. N. Power (MT; CNCI); 1♀, South Australia, N. Renmark , 263m, - 32.8833°S, 140.7166°E, leg. D.C. Darling (MT; CNCI); 2♀, Victoria, Mitcham,?. ii.1983, leg. C. Lai & D. Yu (MT; CNCI); 1♀, Western Australia CSIRO Perth , - 32.333°S, 115.8166°E, 11–23.xi.2002, leg. J. Pinto ( CNCI). NEW ZEALAND: 11♀ & ♂, Nelson, 11.ii.1960, leg. E.W.

Valentine (reared from eggs of Siphanta acuta ; CNCI); 1♀, Auckland, Symonds Str. Cemetery, 36.858 ° S, 74.765°E, 24–25.iii.2010 , leg. L. Masner ( YPT; CNCI) 1♀, Pohara , 23.ii.1993 , leg. L. LeSage (sweep coastal vegetation— Macropiper sp.; CNCI).

Comments. There are few data on the distribution of Aphanomerus . Perkins (1905), Brues (1908), Dodd (1914) and Kieffer (1926) found Aphanomerus only in Australia; Masner & Huggert (1989) confirmed the presence of Aphanomerus in Australia and recorded it also from New Zealand, New Guinea and Sulawesi; Vlug (1995) considered Aphanomerus to be an Australian and Oriental genus. Aphanomerus rufescens was described from Australia by Perkins (1905), and A. pusillus, Perkins was introduced from Australia into Hawai’i in 1904 as a biocontrol agent of Siphanta acuta (Walker) (Flatidae) (Fouts 1936; Lai 1988; Denoth et al. 2002; Gruner 2004). Aphanomerus pusillus was found in New Zealand (Gourlay 1930; Jamieson et al. 2009), where it was probably also introduced.

We consider that Aphanomerus rufescens is not native, but introduced to the USA. The use of Aphanomerus (especially A. pusillus ) in classical biological control of leafhoppers from the early twentieth century has likely contributed to its spread, though we have found no documentation that it was intentionally introduced into the United States of America.

The descriptions of Aphanomerus rufescens (Perkins 1905; Dodd 1914; Kieffer 1926) were insufficient for reliable identification at species level, and consequently our determination was made only after examining photographs of the type specimen of A. rufescens Perkins (BPBM). Because of this, and because Aphanomerus contains parasitoids of some important pests ( Siphanta ) we consider it necessary to redescribe this species.

Description. Female. Colour: head and mesosoma black; metasoma brown with T2 darker than the rest of tergites; head and mesosoma covered with silvery short hairs; legs including coxae, yellow with a reddish tint in some specimens; antenna with the same colour as the legs, but clava brown as in T2.

Head in dorsal view wider that long, subellipsoidal with a coriaceous-imbricate sculpture and sparse long hairs; frons, above toruli, with an alutaceous sculpture; frons in the middle smooth almost without sculpture; occipital and hyperoccipital carina absent; postgenal sulcus and median sulcus of the postgenal bridge absent; postgenal pit present; eyes appearing glabrous, but under high magnification with minute, fine scattered hairs; malar sulcus absent, gena not striate; interantennal process not prominent; clypeus very narrow and short, not wider than the inter-mandibular space, with a row of strong and long setae; mandible bidentate; maxillary palp 2- segmented; labial palp 1-segmented; antenna 7-segmented, with abrupt, massive, compact 4-segmented clava, sensillar formula 1:2:2:1.

Mesosoma with pronotal shoulders clearly visible in dorsal view, but not angular; mesoscutum and mesoscutellum with a clearly visible coriaceous-imbricate sculpture; skaphion and skaphion carina present, clearly visible; antero-admedian line and parapsidal line absent; notauli present, percurrent, rather superficial, not crenulate and convergent posteriorly; terminal, any notaulus with a conspicuous pit; transaxillar carina short but visible; axillular carina not visible; posterior scutellar sulcus deep and wide laterally, not visible medio-posteriorly; metanotum narrow, smooth, not foveolate; metascutellum not visible, overlapped by posteromedial margin of mesoscutellum; propodeum with no foamy structure, with some sparse hairs at sides, glabrous in middle, with clearly visible parallel lateral propodeal carinae; metasomal depression small, with some short hairs and a median carina; clearly visible propodeal spiracle; propodeum with a strong transverse carina posteriorly; along the posterior transverse propodeal carina there is a strong crenulate sulcus, interrupted by lateral propodeal carinae; transverse pronotal sulcus shallow and glabrous; lateral propleural area smooth and lustrous with some sparse hairs, without depression; netrion absent; transaxillar carina in lateral view with one or two striae; mesopleuron smooth, almost glabrous, with a shallow, rather absent mesopleural depression; pleural pit not visible; transpleural sulcus almost transverse, deep and sharply incised; speculum smooth, lustrous and glabrous; femoral depression small; mesopleural carina, present, clearly visible; metapleuron not sculptured, lustrous, rather glabrous, only ventrally near the posterior coxa with some sparse hairs; metapleural pit continuous with a clearly visible, deeply incised metapleural sulcus; metapleural carina, well developed; fore wing with a straight tubular submarginal vein, truncate knob and with nebulous Rs+M (but this is barely visible even on a microscopic slide at 400x); costal and submedian cells glabrous; submarginal vein without setae; hind wing with short stem of tubular submarginal vein; tibial spur formula 1-2-2 and with fore spur bifid.

Metasoma no longer than head and mesosoma combined, hardly convex dorsally, with 6 visible tergites, terminally pointed; T1 trapezoidal, without horn; anterior pits of T1 clearly visible, the space between these pits with strong costae, the length of these costae not surpassing the posterior border of anterior pits of T1; laterally, in the area of the anterior pits, T1 is covered with sparse long setae, but in middle, in the area with sculpture it is glabrous; T2, the largest tergite almost rectangular, smooth, with anterior pits clearly visible; T3–T5 without sculpture, almost glabrous, with only a few sparse hairs; T6 well developed, triangular with sparse hairs; length of T6 the same as the combined lengths of T3–T5; laterotergites present, relatively narrow, almost 1/10 maximum width of S2; ventrally metasoma almost glabrous, with few sparse hairs on S1 and S6; anterior pits of S2 clearly visible without hairs; the felt field of S2 almost absent, indicated only by a hardly visible microsculpture.

Male: with the same colour as female, but the head and mesosoma dark brown or brown. Differs from female in the antenna (8-segmented) and the shape and length of metasoma.

Metasoma shorter than head and mesosoma together (length of head + length of mesosoma = 1.4–1.5× length of metasoma). T2 distinctly trapezoidal and apex of metasoma obtuse. Laterotergites 1/6 maximum width of S2 and wider than those of the female.

Morphological variability. Usually intraspecific variability is shown in the colour of the metasoma, from dark to light brown. Usually the darkest tergite is T2, T1 being sometimes yellowish. Pilosity of T2 also varies, in some specimens the anterior pits of T2 being covered with a dense pilosity. In this case some sparse hairs can be seen on the lateral sides of T2, in contrast to specimens where the anterior pits of T2 have a few hairs and the rest of T2 is glabrous. The shape and size of T2 are also variable. In some cases T2 is long, with sides almost parallel so this tergite is almost rectangular. There are also specimens with T2 a shorter, with sides divergent and in this case the shape of T2 is almost trapezoidal (in these females, the shape of T2 is like the shape of T 2 in males). Although we did not make a rigorous statistical analysis, there was not a clear correlation between the variability of colour, size/ shape of T2 and overall size, and no suggestion of allometry.

Our specimens are a new record of this genus for the continental Nearctic Region.

Figures

FIGURES 25–30. VARIABILITY IN FEMALES OF Aphanomerus rufescens PERKINS.

FIGURES 31–36. Aphanomerus rufescens PERKINS: 31, 32. VARIABILITY OF MALES; 33. FEMALE ANTENNA, LIGHT MICROSCOPY; 34. MALE ANTENNA,LIGHT MICROSCOPY;35. FEMALEANTENNA,SEM, EMPHASIZING THE SENSILLAR FORMULA (35A); 36. FORE AND HIND WINGS.

FIGURES 37–43. Aphanomerus rufescens PERKINS, FEMALE (SEM): 37. HEAD, FRONTAL VIEW; 38. BACK OF THE HEAD; 39. FORE- TIBIAL SPUR;40. MESOSOMA,DORSAL VIEW;41. MESOSOMA,LATERAL VIEW; 42. METASOMA,DORSAL VIEW;43. METASOMA,VENTRAL VIEW.

FIGURES 44–45. Aphanomerus rufescens PERKINS,MALE (SEM): 44. METASOMA,DORSAL VIEW;45.METASOMA,VENTRAL VIEW.

FIGURES 46–48. DISTRIBUTION OF:46. Platyscelio africanus; 47. Tetrabaeus americanus; 48. Aphanomerus rufescens (YELLOW DOTS—PAST RECORDS;RED DOTS—NEW RECORDS).