Eretmocerus lannae Shih & Polaszek, 2015

Shih, Yuan Tung, Polaszek, Andrew, Dubey, Anil Kumar, Chen, Shu-Pei, Yang, Ping-Shih & Ko, Chiun-Cheng, 2015, New species of Eretmocerus Haldeman (Hymenoptera: Aphelinidae) parasitizing Crenidorsum turpiniae (Takahashi) and Aleurothrixus floccosus (Maskell) (Hemiptera: Aleyrodidae) from Taiwan, Journal of Natural History 50, pp. 377-391 : 381-385

publication ID	https://doi.org/ 10.1080/00222933.2015.1075622
DOI	https://doi.org/10.5281/zenodo.4329420
persistent identifier	https://treatment.plazi.org/id/03FD422B-9070-CA6D-FEF4-B4F1FE57FD98
treatment provided by	Carolina
scientific name	Eretmocerus lannae Shih & Polaszek
status	sp. nov.

Treatment

Eretmocerus lannae Shih & Polaszek , sp. nov.

( Figures 1 – 3 View Figure 1 View Figure 2 View Figure 3 )

Diagnosis

Females of Eretmocerus lannae sp. nov. can be identified by having 6 setae on the mesoscutum; a single seta on each mesoscutal side lobe; a short, pale yellow, cylindrical antennal clava, 4.7 – 5× as long as wide ( Figure 1C View Figure 1 ); and prominent frenal arms (circled in Figure 3 View Figure 3 ).

Description (female holotype)

Length, 0.71 mm. (Paratypes, 0.61 – 0.73 mm (n = 10).

Colour. Head yellow. Mesosoma pale yellow. Gaster yellow. Antenna pale yellow. Wings hyaline. Legs pale yellow except basal margin of mid and hind femur.

Head. Vertex with 12 – 13 pairs of setae. Face and occiput with transverse substrigulate sculpture, interscrobal area vertically substrigulate. Face with 24 – 26 setae. Supraclypeal area with 10 – 12 setae. Clypeus with 3+3 setae, 2 short setae on mid margin. Upper posterior head with 26 – 28 setae, 3 pairs of long and robust setae present in a row across the head. Lower posterior head with 15+14 setae, one short seta on the mid part ( Figure 1B View Figure 1 ). Antenna ( Figure 1C View Figure 1 ): radicle 3.8× as long as wide; scape 3.7× as long as wide, 1.94× as long as radicle, 1.76× pedicel length, 0.52× clava length; pedicel 2.21× as long as wide, 1.10× as long as radicle, 0.56× scape length. Funicle I trapezoid, dorsal length 0.5× ventral length. Funicle II 1.4x as wide as long. Clava cylindrical, narrowed at apex, 4.9× as long as greatest width, 1.87× scape length, 3.23× pedicel length. Clava with 5 articulated spines.

Mesosoma ( Figure 2A View Figure 2 ). Mid lobe of mesoscutum with 6 setae, anterior part with cellular reticulate sculpture, remainder with faint elongate reticulations. Side lobe with 1 seta, anterior margins with faint reticulations; axilla with 1 seta, faintly reticulate. Scutellum with 4 setae, anterior pair shorter, 0.87× posterior pair; 2 placoid sensilla placed laterally equidistant from both paired setae, Scutellar reticulation similar to that of mesoscutum. Frenal arms long and exceeding metanotum. Metanotum slightly narrower centrally than propodeum. Propodeum with faint transverse reticulations, central lobe broad and smooth.

Wings. Fore wing ( Figure 2D View Figure 2 ) 2.42× as long as maximum width of disc. Longest posterior marginal fringe seta 0.24× disc width. Base of wing with 1 seta, distal portion of costal cell with 1 seta. Marginal vein with 2 long setae, 11 – 14 setae present between marginal vein and partial linea calva. Submarginal vein 1.11× as long as marginal vein and 3.13× stigmal vein length. Marginal vein 2.52× stigmal vein length.

Legs ( Figures 1D–F View Figure 1 ). Mid tibial spur 0.52× basitarsus length. Hind tibial spur 0.52× basitarsus length.

Gaster ( Figure 2B View Figure 2 ). Gastral tergite I with reticulations on lateral margins; tergites 1 – 6 with paired setae as follows: 1, 1, 1, 2, 2, 2. Syntergum (T7) with 4 setae. Ovipositor somewhat prominent, weakly exserted, 0.86× clava length, subequal to mid tibia; 1.62× scape length.

Male. Unknown.

Holotype ♀ (on slide), Taiwan: Dayuan, Taoyuan, ex Aleurothrixus floccosus on Psidium guajava, 20 February 2013, Y. T. Shih ( NTU).

Paratypes. 10 ♀♀ (on slides), data same as the holotype . (1♀, BMNH; 9♀, NTU) .

Distribution

Taiwan: Dayuan, Taoyuan.

Host

Hemiptera : Aleyrodidae : Aleurothrixus floccosus (Maskell) .

Remarks

The female of Eretmocerus lannae sp. nov. is unusual in having a single seta on the mesoscutal side lobe, a character observed for the first time in the genus Eretmocerus . Generally, Eretmocerus species have 2 – 3 setae on the side lobe. The new species is close to E. trialeurodis Hayat , but differs from it in the length of ovipositor, which is 0.86× clava length and subequal in length to the mid tibia, and in having the mid tibial spur 0.52× the basitarsus, and with fewer setae on the vertex.

Eretmocerus lannae sp. nov. is a potential biocontrol agent of A. floccosus ; the parasitoid population was found to be abundant. Although A. floccosus was infesting heavily both the golden dewdrop ( D. repens ) and guava (P. guajava), only the population on guava was parasitized by E. lannae . The reason for this selective host preference could be plant secondary metabolites, or possibly that the population of A. floccosus on golden dewdrop secretes more wax than the guava population, creating unfavourable conditions for parasitization.

Etymology

The species name lannae is derived from ‘lanna’ a Latin word for ‘ lobe ’, reflecting the prominent frenal arms.