Agistemus riograndensis Johann and Ferla,

Johann, Liana, Carvalho, Gervásio Silva, Majolo, Fernanda & Ferla, Noeli Juarez, 2013, Stigmaeid mites (Acari: Stigmaeidae) from vineyards in the state of Rio Grande do Sul, Brazil, Zootaxa 3701 (2), pp. 238-256: 247-250

publication ID

http://dx.doi.org/10.11646/zootaxa.3701.2.6

publication LSID

lsid:zoobank.org:pub:C424582D-0578-43EF-947C-D673EB1DF571

persistent identifier

http://treatment.plazi.org/id/03E0BF64-FFAD-4C3A-FF67-FF1CFC524011

treatment provided by

Plazi

scientific name

Agistemus riograndensis Johann and Ferla
status

sp. nov.

Agistemus riograndensis Johann and Ferla  sp. nov.

( Fig. 5View FIGURE 5)

Description. FEMALE. Gnathosoma  . Palp coxae with 1 spiniform setae; trochanter without setae; femur with 3 long and serrate setae, 1 of them more robust; genu with 1 long seta reaching distal claw; tibia with 2 setae, 1 claw and 1 accessory claw robust, tarsus with 4 setae, 2 solenidia and 1 trifurcated sensillum ( Fig. 5View FIGURE 5 B). Infracapitulum with 2 pairs of long setae and 2 pairs of adoral setae distally. Idiosoma  . Oval outline. Dorsum: 7 smooth dorsal shields with setae inserted on small tubercles. Prodorsal shield with 3 pairs of long and serrate setae, 1 pair of eyes and 1 pair of post-ocular bodies. Hysterosomal shield with 5 pairs of long and serrate setae. Seta c 1 reaching the base of d 1. 4 small shields each with 1 lanceolate seta (setae c 2 and f). Suranal shield with 2 pairs of setae, h 1 and h 2. Podocephalic canal starting between the base of palps and leg I, extendig to base of leg II. Venter: 3 pairs of slender setae between coxae, 1 a at level of coxa II, 3 a anterior to coxa III and 4 a at level of coxa IV. Anogenital regions with horseshoe-shaped shield that surrounds genital opening ( Fig. 5View FIGURE 5 C) anteriorly, with 2 pairs of agenital setae (ag 1 and ag 2). Genital region with 4 pairs of setae (g 1, ps 3, ps 2, and ps 1). Seta g 1 reaching base of ps 3. Setae ps 3, ps 2 and ps 1 robust and slightly serrate. Leg I – IV setation ( Fig. 5View FIGURE 5 D): coxae 2 (1)- 1-2 - 2; trochanters 1 - 1 - 1 - 1; femora 5 - 4 - 2 - 2; genua 4 - 1 -0-0; tibiae 5 (1)- 5 (1)- 5 (1)- 5 (1); tarsi 12 (1)- 9 (1)- 7 (1)- 7.

MALE. Gnathosoma  . As in female. Idiosoma  . Oval outline. Dorsum: 5 smooth dorsal shields and setae inserted on small tubercles. Prodorsal shield with 3 pairs of long and serrate setae, 1 pair of eyes and 1 pair of postocular bodies. Hysterosomal shield with 6 pairs of long and serrate setae, including seta f. 2 humeral shields with setae c 2. Suranal shield with 2 pairs of setae, h 1 and h 2. Venter: 3 pairs of slender setae between coxae, 1 a at level of coxa II, 3 a anterior to coxa III and 4 a at level of coxa IV. Terminal anogenital region with 5 pairs of setae. Leg I – IV setation: coxae 2 (1)- 1-2 - 2; trochanters 1 - 1 - 1 - 1; femora 5 - 4 - 2 - 2; genua 4 - 1 -0-0; tibiae 5 (1)- 5 (1)- 5 (1)- 5 (1); tarsi 12 (2)- 9 (2)- 7 (1)- 7 (1).

Measurements of this species are provided in Table 4.

Character measured Female holotype Female (n= 14) Male (n= 5) Type material. CAS-03 (MCN). Female holotype from Candiota, V. vinifera, Alfrocheiro  cultivar, 5 March 2007, coll. L. Johann. 4 female paratypes from Bento Gonçalves: 1 female from V. vinifera, Cabernet Sauvignon  cultivar, 7 November 2006, coll. L. Johann; 1 female on same host, Chardonnay cultivar, 5 March 2007, coll. L.B.

Oliveira; 1 female on same host, Merlot cultivar, 7 November 2006, coll. T.B. Horn; 1 female on same host, Pinot Noir cultivar, 3 January 2007, coll. L. Johann; 6 female and 1 male paratypes from Boqueirão do Leão: 2 females and 1 male from V. vinifera, Cabernet Sauvignon  cultivar, 24 April 2006, coll. T.B. Horn; 1 female from V. labrusca, Bordeaux  cultivar, 8 January 2006, coll. T.B. Horn; 1 female with same data, 16 March 2006, coll. T.B. Horn; 2 females with same data, 30 January 2007, coll. T.B. Horn; 2 female and 1 male paratypes from Dois Lajeados: 1 female from V. labrusca, Bordeaux  cultivar, 17 April 2006, coll. T.B.Horn; 1 female and 1 male from V. vinifera, Cabernet Sauvignon  cultivar, 15 January 2006, coll. F.Diel; 1 female and 3 male paratypes from Encruzilhada do Sul, V. vinifera, Pinot Noir  cultivar, 13 February 2007, coll. L. Johann.

Type deposition. Holotype and all paratypes in MCN.

Differential diagnosis. This species is similar to A. brasiliensis  by c 1 setae longer than the distance between the base of c 1 and the base of d 1. In Agistemus riograndensis  sp. nov., setae sci, c 1, d 1, and d 2 are 25 % longer than those in A. brasiliensis  ; the distance between the bases of ve setae is shorter than in A. brasiliensis  ; and the ratio between ve/ve-ve is 2.8–5.8; g 1 setae exceed the bases of setae ps 3, but do not reach the bases of ps 2. In A. brasiliensis  , ve/ve-ve ratio is 1.2–3.4 and gl setae exceed the bases of ps 2 setae. In addition, the measurements of Agistemus riograndensis  sp. nov. are similar to those of Agistemus inflatus Meyer, 1969  . Agistemus riograndensis  sp. nov. bears four setae on genu I and the bases of the dorsal setae are not inflated, whereas A. inflatus  has three setae on genu I and the bases of the dorsal setae inflated.

Etymology. The species name comes from the type locality – the State of Rio Grande do Sul (“ riograndensis  ”).

Remark. The new species was observed together with Panonychus ulmi  ( Tetranychidae  ) and Calepitrimerus vitis  ( Eriophyidae  ), and it is possibly a predator of these phytophagous.

TABLE 4. Measurements of Agistemus riograndensis Johann & Ferla sp. nov.

        Min       Min
    50.9       58.5    
    48.1       13.4    
    43.3       43.4    
    4.1 12.0