Oxycenus maxwelli ( Keifer 1939 )

Chatti, A., Kreiter, S., Lebdi-Grissa, K. & Ksantini, M., 2017, Phytophagous and predatory mites on olive trees in Tunisia. Catalogue, description of one new species and key for identification (Acari, Eriophyidae, Tetranychidae, Tenuipalpidae and Phytoseiidae), Acarologia 57 (2), pp. 233-254 : 235-236

Oxycenus maxwelli ( Keifer 1939)

Oxypleurites maxwelli Keifer, 1939: 152 .

Oxycenus maxwelli Keifer, 1961: 7 .

Common name — olive leaf and flower mite.

Distribution — Oxycenus maxwelli is recorded from Algeria, Armenia, Australia, Brazil, California, Egypt, Greece, Italy, Portugal and Spain ( Vacante 2016).

Material examined — Sfax: Aouled Msallem (34°58’21.97"N, 10°47’20.72"E), April 2008, 56 ♀♀ and 23 ♂♂ and immatures; Hageb (34°42’16.50"N, 10°39’18.97"E), April 2008, 23 ♀♀ and 17 ♂♂ ; Taous (34°56’02.88"N, 10°36’52.77"E), April 2008, 45 ♀♀ and 12 ♂♂ ; Ltayfa (34°44’58.23"N, 10°11’39.67"E) April 2008, 26 ♀♀ and 18 ♂♂ ; Jbenyana (35°03’14.28"N, 10°55’46.63"E), April 2011, 52 ♀♀ 15 ♂♂ and 5 immatures . Karkennah: Sidi Yousef (34°39’30.27"N, 10°59’42.70"E), June 2009, 16 ♀♀ ; Aouled Yaneg (34°40’22.19"N, 11°08’15.07"E), June 2009, 18 ♀♀ and 9 ♂♂ ; Ramla (34°43’17.06"N, 11°12’34.35"E), June 2009, 21 ♀♀ and 14 immatures ; Mellita (34°39’24.43"N, 11°1’59.42"E), June 2009, 26 ♀♀ and 13 ♂♂ ; Ataya (34°44’26.25"N, 11°18’8.47"E), May 2011, 29 ♀♀ and 2 ♂♂ . Gafsa: Oasis Gafsa (34°24’55.53"N, 8° 44’ 42.69"E), April 2008, 62 ♀♀ and 12 ♂♂ ; Guetar (34°20’16.39"N, 8°54’55.85"E), April 2008, 31 ♀♀ and 23 ♂♂ ; Bou Omran (34°21’38.47"N, 9°8’16.61"E), April 2008, 23 ♀♀ and 5 ♂♂ ; Bou Saad (34°21’57.24"N, 9°9’48.46"E), April 2008, 28 ♀♀ . Cap Bon: Grambalia (36°36’46.35"N, 10°31’30.59"E), 58 ♀♀ and 24 ♂♂ , February 2010, 22 ♀♀; Beni Kalled (36°36’44.77"N, 10°31’30.72"E), February 2010, 18 ♀♀ and 6 ♂♂ . Sidi Bouzid: Regueb (34°50’26.08"N, 9°47’49.20"E), May 2009, 17 ♀♀ and 5 ♂♂ ; Sidi Bouzid (35°02’03.70"N, 9°25’24.77"E), May 2009, 45 ♀♀ and 16 ♂♂ .

Notes — the only known host of O. maxwelli is Olea europaea L. This species commonly feeds on the upper surfaces of olive leaves but infests the undersurfaces when populations are high ( Keifer 1939). It also feeds on developing buds and shoots causing malformations and shortening internodes between young leaves (’witch’s broom’ effect). The infestation is most severe in young trees under high temperature and humidity. Heavy infestations of O. maxwelli can cause the premature fall of olive flowers, spotting and distortion of leaves ( Russo 1972).