Stigmella schinivora van Nieukerken

van Nieukerken, Erik J., Doorenweerd, Camiel, Nishida, Kenji & Snyers, Chris, 2016, New taxa, including three new genera show uniqueness of Neotropical Nepticulidae (Lepidoptera), ZooKeys 628, pp. 1-63 : 13-15

Taxon classification Animalia Lepidoptera Nepticulidae

Stigmella schinivora van Nieukerken sp. n.

Holotype male.

Argentina (Misiones), Cataratas del Iguazú. 27.viii.2000, 21J YM5645, E.J. van Nieukerken; leafmines, rather cultivated part of park; Schinus terebinthifolius , e.l. 11-12.ix.2000, RMNH/EvN no 2000148-1, Genitalia slide EvN3986, RMNH.INS.23986 (RMNH).

Differential diagnosis.

A completely leaden coloured species, with orange head and leaden edged scape, collar also leaden. The genitalia do not resemble any other Neotropical Stigmella species closely.

Description.

Male (Fig. 3). Head with frontal tuft yellow, collar leaden grey, scape white, edged grey posteriorly, pedicel white, flagellum leaden; antenna with 23-24 segments (n=3). Thorax and forewings uniformly shining leaden grey, smoothly scaled, hindwings slightly darker. Underside forewing dark grey. Abdomen without anal tufts.

Female (Fig. 4). Antenna with 20-21 segments (n=2). Scape hardly with grey edging, hindwings paler than in male, same colour as forewings.

Measurements. Male: forewing length 1.7-1.8 mm (n=2), wingspan: 4.0 mm (n=2). Female: forewing length 1.7- 2.0 mm (n=2), wingspan 3.9-4.2 mm (n=2).

Male genitalia (Figs 34-37). Total length vinculum 185-200 µm, valva 135µm, phallus 260-285 µm (n=3). Phallus asymmetric, anteriorly bending to the left, vesica with many small cornuti.

Female genitalia (Figs 38-40). Length of bursa ca 340 µm. T8 apically pointed, with ca 15-20 setae total. Posterior apophyses longer than anterior ones. No sclerotisations or signa observed in the single relatively poor genitalia slide.

Biology.

Host plants. Anacardiaceae : Schinus terebinthifolia Raddi, the Brazilian pepper tree.

Leafmines (Figs 41-43). The mine is a much contorted upper surface gallery, track often doubling back, usually confined to the small space between two lateral veins and the midrib; mine filled with black frass; larval exit hole on upperside. Mine poorly visible in transmitted light, or from underside, due to leaf thickness.

Egg. The egg is always deposited on leaf upperside, frequently against a lateral vein.

Larva: green.

Voltinism and habits. Larvae were collected in late August, adults emerged indoors in September, and were caught in malaise traps from late September to late October. We collected the mines on planted trees, together with large numbers of the then still undescribed Leurocephala schinusae Davis & McKay ( Davis et al. 2011).

Distribution.

Argentina: Misiones.

DNA barcode.

We barcoded two specimens from our reared series (not the Holotype), that appeared to match with a large number of records from the Malaise traps in Misiones, giving a total of 26 barcodes, all in BINBOLD:ACN0764. One specimen was also sequenced for other genes and will be used in a forthcoming analytical paper. Sequences may be retrieved in BOLD and later also in Genbank under voucher/sample ID RMNH.INS.24681.

Remarks.

Molecular analysis suggest that Stigmella schinivora is closely related to the North American Anacardiaceae feeding species in the Stigmella prunifoliella group, which suggests a single host-shift from Rosaceae or Rhamnaceae , but in some analyses it also groups with the European Stigmella diniensis (Klimesch, 1975) that feeds on Cistaceae . It is currently the only known Neotropical species of this group of species.

Davis et al. (2011) described four gracillariid leafminers of the Brazilian pepper tree, partly aiming at finding suitable candidates to release as biological control against the invading pepper tree in Florida. They did not report on any nepticulid, but we assume that Stigmella schinivora is also widespread with the host. It could be added to the list of potential control candidates, but we doubt its effectiveness, given the small size. Also the fact that several Anacardiaceae miners are not very host specific is a risk, as released control species might shift to native North American Rhus and Toxicodendron species.

Etymology.

Schinivora: an adjective, derived from the Latin noun Schinus (host genus), stem schin-, and verb voro (=devour).

Other material examined.

4♂, 3♀, 4 larvae, leafmines. Argentina: 1♂, 1♀, 3 larvae in alcohol, leafmines, Misiones, Cataratas del Iguazú. 27.viii. 2000, leafmines, rather cultivated part of park; leafmines on Schinus terebinthifolia , e.l. 11-12.ix.2000, RMNH/EvN no 2000148-1, E.J. van Nieukerken; Genitalia slides EvN3986, RMNH.INS.23986 (RMNH); 1♂, 1♀, 1 larva in alcohol, leafmines, same locality, but e.l. 14-15.ix.2000, RMNH/EvN no 2000149-1, Genitalia slides ♂ EvN4500, ♀ EvN4681, RMNH.INS.24500, 24681 (RMNH); 1♂, 1♀, in ethanol 96%, Misiones, Obera, CIAR, 26.ix.-3.x.2013, Pablo Tubaro, Malaise trap, GMP#05155, -27.445, -54.94, 147 m, DNA-barcoded, BIOUG13587-H11 & BIOUG13589-E08 (MACN), 1♂, ditto, but 24-31.x.2013, GMP#05157, BIOUG13956-F02, whole specimen mounted on slide, EvN4834 (MACN).

More data from BOLD

[specimens not examined, same BIN]. 21 adults, in ethanol 96%, Argentina, Misiones, Obera, CIAR, 23.v.-24.x.2013, Pablo Tubaro, Malaise trap: 1, trap GMP#05146, 23-30.v.2013, BIOUG12989-H09; 2 ad., trap GMP#05149, 26-4.vii.2013, BIOUG23823-E01, BIOUG23823-E11; 2 ad., trap GMP#05150, 11-18.vii.2013, BIOUG24501-C12, BIOUG24505-B08; 1 ad., trap GMP#04812, 18-25.vii.2013, BIOUG13317-B04; 4 ad., trap GMP#05151, 25-1.viii.2013, BIOUG24746-D11, BIOUG24746-E04, BIOUG24746-E06, BIOUG24746-H10; 5 ad., trap GMP#04813, 1-8.viii.2013, BIOUG13418-F06, BIOUG13418-G07, BIOUG13418-H11, BIOUG13420-A11, BIOUG13421-G02; 1 ad., trap GMP#04815, 22-29.viii.2013, BIOUG24913-G01; 2 ad., trap GMP#04816, 5-12.ix.2013, BIOUG25104-F01, BIOUG25104-F02; 1 ad., trap GMP#04817, 19-26.ix.2013, BIOUG25154-H01; 2 ad., trap GMP#04819, 17-24.x.2013, BIOUG24948-E10, BIOUG24952-A07 (all in MACN).