Description of Telamoptilia grewiae sp. n. and the consequences for the definition of the genera Telamoptilia and Spulerina (Lepidoptera, Gracillariidae, Gracillariinae)

Abstract The new species Telamoptilia grewiae, reared from leafmines on Grewia biloba (Malvaceae) is described with details on adult and immature stages. The larval head and the pupa are described for the first time in Telamoptilia Kumata & Kuroko, 1988, and are illustrated with scanning electron micrographs and line drawings. Photographs of adult habitus, wing venation, male and female genitalia, as well as host plant and mines are provided. The apomorphic adult and larval characters of the new species in Telamoptilia are discussed in relation to the recognition of the genera Telamoptilia and Spulerina Vári, 1961.


Introduction
The genus Telamoptilia Kumata & Kuroko, 1988 is globally represented by five species that may be found in the Oriental and African regions. The type species T. cathedraea (Meyrick, 1908) is geographically shared by the Oriental Region and Madagascar (De Prins and De Prins 2014). Three species are currently known from China, including T. cathedraea, T. hemistacta (Meyrick, 1924), and T. prosacta (Meyrick, 1918).
The larvae of Telamoptilia species are leaf miners. Three plant families are known as hosts for Telamoptilia: Malvaceae, Amaranthaceae and Convolvulaceae (De Prins and De Prins 2014). Vári (1961) briefly described the biology of T. geyeri (Vári, 1961). Kumata et al. (1988) described the biology and the larval body chaetotaxy of three species: T. cathedraea, T. prosacta and T. tiliae (Kumata & Ermolaev, 1988). However, no larval head chaetotaxy and pupal features of Telamoptilia have been described so far.
Telamoptilia grewiae sp. n. is associated with Malvaceae and is described in the present paper from adult external characters, male and female genitalia, wing venation and immature stages. The larval head and pupal features are described for the first time in Telamoptilia.

Methods
Field investigations were carried out in Mt. Baxian National Nature Reserves (40°11'N, 117°32'E), 300−600 m, Tianjin, China, from May to September in 2013 and June 2014. Leaves containing mines with larvae were placed in sealed plastic bags, or rearing containers with moist cotton. Larvae removed from mines were immersed in nearly boiling water for 30 seconds, and then were kept in 75% ethanol for morphological examination. Last instar larval skins, pupae, and exuviae were kept in 75% ethanol. Pupae in rearing containers were placed outdoors to overwinter, and were transferred into the laboratory at 20 °C on February 6, 2014. Emergence successively occurred from March 9 to early-April 2014. Adults were collected chiefly by rearing from immature stages, and occasionally by light trap.
Adult photographs were taken with a Leica M250A stereo microscope. Genitalia and wings were dissected and mounted according to the methods introduced by Li (2002), but stained with Eosin Y and/or Chlorazol Black, and the illustrations were prepared by using a Leica DM750 microscope, and refined in Photoshop® CS4 software. For scanning electron microscopy, larvae and pupae were dehydrated in gradient ethanol, dried in vacuum and coated with gold in a SCD 005 Sputter Coater (BAL-TEC), then operated with a voltage of 15 kV using Quanta 200 environmental scanning electron microscope (SEM) (FEI, Oregon). Line drawings were outlined from the photos taken by the Leica M250A stereo microscope, using path tool in Adobe Photoshop® CS4 software. Photographs of host plant, mines and a live adult were taken in the field using Canon PowerShot G10 digital camera.
All the specimens studied, including the types of the new species and the vouchered larvae and pupae, are deposited in the Insect Collection, Nankai University, Tianjin, China.

Taxonomy
Telamoptilia grewiae sp. n. http://zoobank.org/584C70BC-8783-4E0E-A680-185E5EF7E1C7 Figures 1−32 Description. Adults (Figs 1−2) with wing span 6.0−8.0 mm. Head silvery white, tinged with gray on face. Labial palpus grayish white, colored blackish gray on outer surface of distal half of second segment and before apex of third segment. Maxillary palpus white, with middle or distal half blackish fuscous. Antenna with scape white on posterior half, blackish gray on anterior half and distal portion, flap blackish gray tinged with white, as wide as scape in frontal view; flagellum silvery grayish fuscous, with each unit blackish distally. Thorax and tegula blackish gray mixed with white. Legs mostly white; foreleg with coxa blackish fuscous basally and distally, femur and tibia blackish fuscous, tarsus blackish gray distally on each except last segment; midleg with coxa blackish fuscous distally, femur blackish fuscous, except white medially and distally on dorsal surface, with ventral scale expansion blackish fuscous, tibia blackish fuscous basally and distally, white medially, tarsus white, each except last segment dotted blackish fuscous distally; hindleg with coxa blackish fuscous distally, femur blackish fuscous distally on outer surface, tibia blackish fuscous basally and distally, tarsus with basal three segments blackish fuscous distally, fourth segment dotted blackish fuscous dorso-distally. Forewing grayish fuscous to blackish fuscous; costal margin with a white spot basally at about 1/10 and one before apex, the former sometimes touching fold posteriorly, with white stria at distal 3/10 and 1/6 obliquely outward, reaching middle of wing and near termen respectively; transverse white fascia from costal 1/3 and 1/2 obliquely outward, reaching dorsal 1/2 and before end of fold respectively, edged with blackish fuscous to black scales, inner fascia wider than outer one, widened on posterior half; small white dot on distal end of M 3 , two or three small white dots along termen; apex blackish fuscous; cilia mostly blackish fuscous basally, gray distally, white adjacent to white markings, white on basal 1/4, black on median part, gray distally at apex, gray along dorsal margin. Hindwing and cilia uniformly gray.
Variations. The white costal spot at about basal 1/10 is sometimes reduced to a small dot near the costa, the white costal stria at distal 3/10 is occasionally extended to unite the dot on the distal end of M 3 , the costal stria at distal 1/6 is sometimes wedgeshaped or absent, the white dot at the distal end of M 3 sometimes moves to near distal end of cell, and the small white dots along termen sometimes are absent.
Venation (Fig. 7). Forewing with R 5 totally untraceable, thus R 4 not stalked, otherwise matching the generic characters (Kumata et al. 1988), with most notably the absence of R 1 .
Diagnosis. The new species mostly resembles T. prosacta, especially in the male genitalia. However, it can be recognized by the male genitalia with the tegumen having 3−4 long setae on each lateral side, and the valva width does not change in the basal 3/4; in T. prosacta, the tegumen has 9−12 long setae on each lateral side and the valva is slightly wider at middle. In the female genitalia, T. grewiae sp. n. can easily be separated from all other Telamoptilia by the extremely short ductus bursae, not reaching the anterior margin of the seventh abdominal segment. The signum lacks a median process and is thereby more similar to signa in Spulerina, especially to that of S. parthenocissi Kumata & Kuroko, 1988, than to those in Telamoptilia.  24-vi-2013, emerged 6−7-vii-2013, 1♂, 1♀, larva coll. 29-vi-2013, emerged 5-vii-2013, 4♂, 3♀, larva coll. 8-viii-2013, emerged 19−20, 22-viii-2013, 1♂, 1♀, emerged 13, 22-ix-2013, 1♂, larva coll. 12-ix-2013, emerged iv-2014 (indoors) Biology. The larva mines on the upper surface of the host plant leaf. The mine begins as an epidermal silvery curved white line which soon enlarges to a whitish blotch. Yellowish-fuscous or fuscous lines can be found on the surface of the blotch. As the larva develops, the blotch usually incorporates the earlier linear mine. The last instar larva vacates the mine for pupation by chewing a semicircular opening near the margin of the blotch. No body colour transfer occurs in the full-grown larva of this species, compared to other Telamoptilia larvae which turn red when fully grown (Kumata et al. 1988). Some host plants can be seriously damaged by the mines in early September. Cocoons are usually found inlaid the leaf wrinkles, or occasionally in the corner of the rearing container. The cocoon is brown, with 2−3 brown minute bubbles on the surface. This species overwinters in pupa.
Etymology. The specific name is derived from the host plant genus Grewia, indicating the host of the new species.

Discussion
The forewing venation of T. grewiae sp. n. is unique within the Acrocercops group: R 1 and R 5 are absent, thus R 4 is not stalked with R 5 . The absence of R 1 is apomorphic for Chrysocercops Kumata & Kuroko, 1988 (occasionally present), Telamoptilia and Spulerina (Kumata et al. 1988, Kumata 1992. Although R 1 is also absent in Dendrorycter Kumata, 1978, it will not be discussed here since its status within the Acrocercops group is still debatable (Kumata et al. 1988). The forewing patterns and the genitalia of Chrysocercops are rather different from those of T. grewiae sp. n. All other Telamoptilia and Spulerina have R 5 , or at least R 5 is visible distally and stalked with R 4 (Kumata et al. 1988). Currently there is not enough evidence for assigning the new species without R 5 to a new genus. A comprehensive study of more species is required for further generic definition. Kumata et al. (1988) distinguished Telamoptilia from Spulerina by the antennal scape having a minute flap, the absence of the fan-shaped comb of the valva and the signum with median process. Telamoptilia grewiae sp. n. has a flap as wide as the antennal scape and a signum lacking a median process, which is most similar to S. parthenocissi as stated in the diagnosis section. Therefore the signum without median process is not an autapomorphy for Spulerina when defining Telamoptilia and Spulerina. The larval seta XD1 of T. grewiae sp. n. is placed near the anterior margin of the prothorax shield, which resembles that of Spulerina Vári, but differs from that of Telamoptilia that has XD1 of variable placement between D1 and D2 (Kumata et al. 1988). The fully grown larva of Telamoptilia and Spulerina changes body colour into red (Kumata et al. 1988), but colour transfer does not occur in T. grewiae sp. n. Consequently, the most important generic character to distinguish Telamoptilia from Spulerina is the absence of the fanshaped comb of the valva as defined by Kumata et al. (1988), and the minute antennal scape flap and the signum with median process should be excluded for generic definition when taking T. grewiae sp. n. into consideration. The position of seta XD1 and the feature of larval body colour transfer vary within Telamoptilia, thus should not be adopted as generic characters. Considering the unique characters of T. grewiae sp. n., its phylogenetic relationship to other species of the genus Telamoptilia requires further study.