Neoseiulus houstoni Schicha, 1987

Kreiter, Serge, Payet, Rose-My, Douin, Martial, Fontaine, Olivier, Jacques, Fillâtre & Bellec, Fabrice Le, 2020, Phytoseiidae of La Réunion Island (Acari: Mesostigmata): three new species and two males described, new synonymies, and new records, Acarologia 60 (1), pp. 111-195 : 121-124

Neoseiulus houstoni Schicha

Neoseiulus houstoni, Schicha 1987: 111 ; Chant & McMurtry 2003a: 23; Moraes et al. 2004a: 123.

Neoseiulus recifensis Gondim Jr. & Moraes 2001: 77 ; Chant & McMurtry 2003a: 23; Moraes et al. 2004a: 140, new synonymy.

Neoseiulus barreti Kreiter, in Furtado et al. 2005: 135 , new synonymy.

These three species belong also to the cucumeris species group of Neoseiulus like previous species. However, whereas Chant and McMurtry (2003a) classified N. recifensis in the cucumeris species subgroup, N. houstoni was placed in the paraki species subgroup (also in the cucumeris species group), despite the two species having identical spermathecae ( Chant and McMurtry 2003a). Neoseiulus barreti was described later than 2003, is not mentioned in Chant and McMurtry (2007) but the spermatheca is also identical to that of the two former species.

Neoseiulus houstoni was the first species collected and described in 1987 on Vigna unguiculata (L.) Walp. in Queensland, Australia ( Schicha 1987).

Neoseiulus recifensis was discovered for the first time in Brazil in 2001 (Gondim Jr. and Moraes 2001), collected on Cocos nucifera L. in Recife and Itamaraca , Pernambuco, Brazil. It was collected then in 2007 and 2008 in Brazil in the states of Alagoas, Bahia, Cera, Paraiba and Rio Grande do Norte (Fiaboe et al. 2007; Lawson-Balagbo et al. 2008). Finally, it was collected in La Réunion Island in 2011 within a survey investigating potential predators of R. indica on coconut (Moares et al. 2012).

Two females of N. barreti were collected, only one time, in Brazil in 2004 on Solanum paniculatum L. in Itapaje , Ceara, Brazil and described later ( Furtado et al. 2005).

Biology of the three species remain unknown. Males of the three species are unknown.

Specimens examined: 37 ♀♀ + 8 ♂♂ + 4 im. in total, 24 ♀♀ + 8 ♂♂ measured. Langevin – Jacqueline Waterfall (aasl 5 m, Long 55°64’40” E, Lat 21°38’69” S), 4 ♀♀ + 2 ♂♂ on Casuarina equisetifolia L., and 3 ♀♀ + 1 im. on Scaevola taccada Vahl , 19/7/2017 ; Saint- Pierre – Bassin-Plat CIRAD Research Station (aasl 153 m, Long 55°29’18” E, Lat 21°19’25” S) , 1 ♀ in plot H, 12/4/2016; 1 ♀ on B. pilosa , 1 ♀ on Euphorbia hypericifolia Lam. , and 1 ♀ on P. maximum , 20/2/2017; 1 ♀ on Artocarpus heterophyllus Lam. , 5 ♀♀ on C. equisetifolia , 1 ♀ on Acacia mearnsii De Wild. , and 2 ♂ on Crotalaria retusa L., 27/2/2017; 4 ♀♀ + 2 im. on B. pilosa , 2 ♀♀ on L. leucocephala , 1 ♀ on Malvastrum coromandelianum (L.), and 8 ♀♀ + 4 ♂♂ + 1 im. on Parthenium hysterophorus L., 30/3/2017; 1 ♀ in plot CC, 3/04/2017 and 1 ♀ in plot CC, 6/04/2017 ; 1 ♀ on B. pilosa , 19/6/2017; 1 ♀ on A. viridis , 20/6/2017.

We have also examined the following type or additional material:

• The holotype of N. houstoni ;

• The holotype, paratypes female and additional female material of N. recifensis ;

• One paratype female of N. barreti .

Remarks: character measurements of the 24 females collected in La Réunion ( Table 5 ) agree very well with those obtained from females of N. barreti or N. recifensis from Brazil and females of N. houstoni from Australia described previously (Gondim Jr. and Moraes 2001, Schicha 1987, Furtado et al. 2005). We consider so far that our specimens can be anyone of the three species and that examination of the specimens collected in this study can lead to anyone of the three species. Consequently, the morphometrics strongly suggest synonymy.

There are however some discrepancies between our measurements and observations and previous descriptions of the three species. In the three descriptions:

• Dorsal shield is reticulated in the description of N. barreti in the anterior lateral margins and starting to the back of s4 and on all the posterior part of the dorsal shield except the center;

• VA shield has straight slightly convex margins in Schicha 1987 and not in the two other species as a concave part exists in this margin just after ZV2 position;

• Z4 and Z5 are progressively tapered in drawings of N. barreti and Z5 seems longer ( Furtado et al. 2005) vs for other species they are blunt/rounded apically (or more regularly parallel-sided);

• Macrosetae SgeIV, StiIV and StIV are mentioned as setaceous for N. recifensis ( Moraes and Gondim Jr 2001) but seem slightly knobbed on illustrations of the species. SgeIV and StIV are slightly knobbed for N. barreti and N. houstoni and StiIV is not mentioned for N. houstoni;

• two teeth on the fixed digit and no tooth on the movable digit are mentioned for N. barreti and N. recifensis but three teeth for fixed digit and one recurved tooth for the movable digit are mentioned for N. houstoni ;

• Spermathecae of N. barreti and N. recifensis are mentioned as trumpet-shaped but as bellshaped for N. houstoni ;

• Setae JV5 seem longer in N. barreti description and shorter in those of N. houstoni and N. recifensis ;

• 6 poroids around genital/ventrianal shield are drawn for N. recifensis but only 4 for N. barreti and 0 for N. houstoni ;

• Occurrence of JV3 is mentioned in the text of description of N. barreti but not illustrated ( Furtado et al. 2005). These setae are not indicated for description of N. houstoni and N. recifensis .

• Chaetotactic formulae are not precised in the description of N. houstoni but mentioned only for genu II for N. barreti and for genua II and III for N. recifensis .

Our examination of the type material for N. barreti (one paratype ♀), N. houstoni (the single specimen found, the ♀ holotype) and N. recifensis (the ♀ holotype, one ♀ paratype and seven additional ♀) shows:

• dorsal shields of the three species present exactly the same reticulation as drawn in Furtado et al. (2005) for the description of N. barreti ;

• VA shield present only a slight concavity after ZV2 position in N. houstoni ;

• Z4 and Z5 are progressively tapered regularly parallel-sided in the three species and Z5 is of the same length (see table 8);

• Macrosetae SgeIV, StiIV and StIV are: rounded apically for SgeIV, pointed apically for StiIV and slightly knobbed for StIV for the three species;

• Three teeth on fixed digit (two strong anterior and one small tooth posterior to pilus dentilis) and one small recurved tooth in the anterior part of the movable digit for the three species, just as drawn by Schicha (1987);

• Spermathecae of N. barreti and N. recifensis are drawn exactly in the same way in original descriptions ( Schicha 1987; Moraes and Gondim Jr. 2001; Furtado et al. 2005) and are identical in the three species after our examination (and “bell-shaped” seems more appropriate for the shape description);

• Setae JV5 are of similar length for the three species (see table 5);

• 6 poroids are present around genital/ventrianal shield for the three species;

• The mention of JV3 was an error in the text of the description of N. barreti . This seta is not present in the venter of that species and also not present in the two others;

• Chaetotactic formulae are identical for the three species: Genu II: 2-2/0 - 2/0-1 (seven setae); Genu III: 1-2/1 - 2/0-1 (seven setae).

Considering all these information, we can conclude that the three species are synonyms. Consequently, our specimens are identified as the first species described among the three species, N. houstoni . The valid species name is thus Neoseiulus houstoni (Schicha) . Previous specimens collected in La Réunion Island and identified as N. recifensis are renamed N. houstoni . Consequently, this is the first report of that species in La Réunion Island.

The male (for the three species) being unknown, it is herein described for the first time, based on La Réunion specimens.