Amblyseius sakalava Blommers, 1976

Kreiter, S., Mailloux, J., Tixier, M. - S., Le Bellec, F., Douin, M., Guichou, S. & Etienne, J., 2013, New Phytoseiid Mites Of The French West Indies, With Description Of A New Species, And New Records (Acari: Mesostigmata), Acarologia 53 (3), pp. 285-303 : 290-291

Amblyseius sakalava Blommers

Amblyseius sakalava Blommers, 1976: 96 ; suspected junior synonym of Amblyseius largoensis (according to Ueckermann and Loots, 1988).

Biology — Amblyseius sakalava was first found in Madagascar on Corchorus trilocularis ( Blommers, 1976) and then in a search for native natural enemies of Tetranychus urticae Koch in Sri-Lanka, collected on Manihot esculenta and identified by Dr Viebergen ( Wijesekara, 2006). Its life history, reproductive performance on different foods and functional response to the prey were studied in the laboratory. At an average temperature of 29°C, when fed on pollen, A. sakalava completed its life cycle (egg to adult) in 4.5 days on average. The mean preovipositional period is 4.1 days and a female lays an average of 2.2 eggs per day when fed on T. urticae and 1.9 eggs per day when fed on pollen of Tridax procumbens (Asteraceae) . The predatory mite reproduces equally when fed on this pollen and a mixture of T. procumbens pollen and the prey mite. But the reproductive performance was significantly lower when the predatory mite was fed on Tetranychus urticae Koch mite alone or pollen of Tithonia diversifolia or a mixture of T. diversifolia pollen and the latter prey mite. Study of functional response showed a typical type 2 response ( Wijesekara, 2006).

Previous Records — Madagascar ( Blommers, 1976; Moraes et al., 2004b), Sri Lanka (Viebergen, in Wijesekara, 2006).

Specimens examined — Guadeloupe, Basse- Terre , RiviŁre Corossol, Route des Mamelles, 16°10’N, 61°41’W, alt. 221 m, 1 ♀ on Syngonium podophyllum, Kreiter coll., 22 Dec. 2008 .

Remarks — this is the first record of this species in the West Indies. The measurements of the single specimen collected fit rather well the measurements given by Blommers (1976). This species was considered as a junior synonym of Amblyseius largoensis (Muma) by Ueckermann and Loots (1988). We fully disagree with this claimed synonymy as to our knowledge it was not demonstrated and as several characters are different between the two species: A. sakalava has 30 % longer measurements for several setae, especially Z5, nearly two times longer cervix of the spermatheca, at least 7 poroids on the dorsal shield to up to 15 compared to none to three maximum in A. largoensis , and the posterior limit of the sternal concave instead of straight in A. largoensis . However as we have collected only one specimen, all these differences have to be examined carefully on more individuals and the potential synonymy studied with modern analysis means.

The measurements of the adult female presently found are as follow: dorsal shield smooth, dorsal shield length 365, width 258, 7 solenostomes (gd 1, 2, 3, 4, 5, 8 and 9), j1 35, j3 52, j4 5, j5 8, j6 8, J2 8, J5 13, z2 15, z4 13, z5 8, Z1 10, Z4 100, Z5 264, s4 93, S2 10, S4 8, S5 8, r3 10, R1 8, all setae smooth, st1- st1 65, st2-st2 70, st1-st3 68, posterior margin of the sternal shield straigth, metapodal 1 length 20, width 5, metapodal 2 length 15, width 1, ventrianal shield 108 long, 55 wide at level of anterior corners and 68 wide at level of anus, 4 poroids around the ventrianal shield and genital shield, JV5 63, spermatheca 33 long and 5 width, SgeI 45, SgeII 38, SgeIII 43, StiIII 40, SgeIV 118, StiIV 83, StIV 70, macrosetae whip-like, fixed digit of chelicerae 33, mobile digit of chelicerae 33, 11 denticles on fixed digit and 5 on mobile digit.