Introduction
The Chapala lake, around which the collections were performed, is home to many endemic species, being the largest lake in Mexico with a surface area of 114,659 ha, is located at coordinates 20°13'N and 103°03'W and is considered a Ramsar site since February 2009 with assignment number 1973 (Ramsar Sites Information Service, 2022).
The geographic location of Mexico often presents a rich mixture of Nearctic and Neotropical arthropod faunas (Davis, 2000); however, the study of lepidopteran leafminers in Mexico has been scarce, as there are a large number of undescribed species, particularly among the smaller micro-moths such as leafminers (Heppner, 2004). Lopez-Muraira et al. (2020) report Antispastis xylophragma (Meyrick, 1926) as a leaf miner of Solanum umbellatum (Solanaceae) and also records Rifseria fuscotaeniaella (Chambers, 1878) mining the leaves of Montanoa tomentosa (Asteraceae) (Lopez-Muraira et al., 2022). To these contributions is added Phyllocnistis psittacanthusella (Heppner & Lopez-Muraira, 2020),a gracillariid that mines the leaves of Psittacanthus calyculatus, a parasitic plant of the Loranthaceae family.
The Gracillariidae family has 2,016 species recognized worldwide and despite the wide diversity of habitats in our country, only 14 species have been recorded to date for Mexico and it is estimated that there are close to 450 species yet to be discovered (Heppner, 2004; Heppner & López-Muraira, 2020).
Of the genus Caloptilia, 322 species have been reported worldwide (De Prins & De Prins, 2006-2022), but there are only 20 species known for the Neotropical Region and only two species reported for Mexico, C. burserella (Busck) and C. perseae (Busck), both as avocado leafminers (De Prins et al., 2016; De Prins et al., 2019). Caloptilia persea is considered a minor pest of avocados in Florida (Glenn et al., 2003).
Within the mining microlepidoptera, the genus Caloptilia contains the largest moth species of Gracillariidae (Núñez & Barro, 2011) for example, the species C. hemidactylella (Denis & Schiffermüller), C. theivora (Walsingham), and C. stigmatella (Fabricius) can reach up to 14 mm in wing spread (Corver et al., 2011; Park & Han, 1986; Shin et al., 2015). This genus has been reported worldwide feeding on a great diversity of plant species, including members of the families Sapindaceae, Betulaceae, Anacardiaceae, Lauraceae, Fabaceae, and Euphorbiaceae; The Caloptilia stigmatella (Fabricius) larva has been found feeding on several species of the Salicaceae family, especially the genera Salix and Populus, although it has also been reported on several species of the Fabaceae and Myricaceae families (De Prins & De Prins, 2006-2022). In this study, the presence of this gracilarid species for the first time in Mexico, and although other species of Caloptilia, were reported, whose larvae have been reported feeding on plants of the Sapindaceae family, this is the first report on Serjania racemosa.
Material and Methods
During the period from November 7th, 2021 to January 16th, 2022, eight foliage collections were made to search for the larvae of microlepidopteran leafminers of the climbing species known as bejuco or bejuco three-in-one, identified as Serjania racemosa (Figure 1) using the taxonomic key of Rzedowski & Rzedowski (2006). Plant samples were collected near Mezcala town (20°19'58 "N 103°03'10 "W) in the municipality of Poncitlán, Jalisco, Mexico. The plant material, consisting of leaves and branches, was placed in plastic containers of 9.5 cm diameter by 14.25 cm high with a 30 mesh lid and placed in an incubation chamber with a controlled temperature of 25°C and 55 % relative humidity for three weeks and with daily inspections to obtain the adults of the leafminer microlepidopteran species.
Serjania racemosa reported as a medicinal plant (Andrade-Cetto & Heinrich, 2005; Casanova-Pérez et al., 2022) is characterized as a climbing plant of the Sapindaceae family. They are shrubs that present petioles 6 cm long, biternate leaves 17 cm long and 23 cm wide; sub-rhombic leaflets up to 7 cm long and 5 cm wide; serrate margin; thyrses up to 14 cm long and 2. 5 cm in diameter; white or yellow flowers (Figure 2) with 4 petaloid sepals, the outer ones 2 mm and the inner ones 2.3 to 3.5 mm long, petals up to 3.5 mm long; fruit up to 3 cm long (Figure 3). In the study area, it remains green all year round and therefore represents a nutritional source for many insects.
A total of four adult male specimens of the species determined as Caloptilia stigmatella (Fabricius) were obtained, using for their identification the external morphological descriptions and male genitalia published by Park & Han (1986) and Shin et al. (2015). The insects were deposited in the entomological collection located within the CREG Herbarium of the Instituto Tecnológico de Tlajomulco in Jalisco, Mexico. Previous records of Gracillariidae in Mexico were consulted using as a basis the publication of Davis & Miller (1984), showing no previous record of Caloptilia stigmatella (Fabricius) in Mexico, finally the classification scheme of Kawahara et al. (2017) and De Prins et al. (2019), were used.
Results and discusión
Family: Gracillaridae Stainton, 1854
Subfamily: Gracillariinae Stainton, 1854
Caloptilia stigmatella (Fabricius, 1781).
Tinea stigmatella Fabricius, 1781:295-296
Type locality: England
Examined material:
Mexico, Mezcala, Jalisco. 4 males deposited in the entomological collection located in the CREG Herbarium of the Instituto Tecnológico de Tlajomulco in Jalisco. Cat.: ITTJ071121M1, ITTJ071121M2, ITTJ160122M3 and ITTJ091022M4. H.R. Iruegas leg, new record for Mexico.
Caloptilia stigmatella has a worldwide distribution, mainly in the Holarctic Region, and although originally described for England, it is found throughout Europe and Asia, Canada, and on the Atlantic slope in the United States of America, including Florida and Texas (De Prins & De Prins, 2006-2022).
Description:
Adult males (Figure 4) have an average wing spread of 11.875 mm (±0.479 mm) and are easily distinguished given that the forewings are dark brown in color and have a light yellow sub-triangular spot extending from the costa of the wing at its widest part and narrowing posteriorly; there is also a small yellow spot at the base of the anal area of the wing. Hindwings are narrow and uniformly light brown, with long tufts of piliform silks of the same color. The male genitalia (Figure 5) has a narrow, triangular vinculum, dilated apically and 1.2 times shorter than the valves, the latter are covered with piliform silks that become longer apically. The aedeagus (Figure 6) is pointed at the apex and has a membranous covering. The larvae produce an almost rectangular-shaped lesion that undermines the leaves forming an interveinal spot (Figure 7), subsequently rolling the leaf to prepare to form the pupa (Figure 8).
Discussion
The analysis of this study indicates that Caloptilia stigmatella stands out for its worldwide distribution, especially in cold regions. Halffter & Morrone (2017), reported that insect migration from the Nearctic Region is mainly through the Mexican Transition Zone comprising the Sierra Madre Occidental, Sierra Madre Oriental, Sierra Madre del Sur, and the Trans-Mexican Volcanic Belt. The presence of this species in Mexico suggests the use of these geographic corridors. The various bibliographic consultations did not record any report on a Neotropical distribution of Caloptilia stigmatella, so it is likely that due to its dispersal capacity, it could be distributed towards southern Mexico, this is possible since this species is found in most of the territory of the United States of North America, including the border states of California and Texas (Moth Photographers Group, 2019). Likewise, Halffter & Morrone (2017), mention that the genera Onthophagus and Copris (Scarabaeidae), as well as Bombus (Hymenoptera:Apidae), which present a Paleoamerican distributional behavioral pattern, are an example of this phenomenon since they have species that arrived to North America from Eurasia and present taxa in the Mexican Transition Zone.
Conclusions
To date and including the present study, only 15 species of gracilarids have been reported for Mexico, which represents 0.75 % of the total number of species recorded worldwide, which indicates that this group is scarcely studied in our country. This publication is part of the effort to identify the present species of this group of leafminers and to define their host plants in the State of Jalisco. The Caloptilia genus maintains feeding preferences on plants of the Salicaceae family, including C. stigmatella; however, in the present study, Serjania racemosa (Sapindaceae) is added as another host species for Mexico, and the geographic distribution of C. stigmatella, which in America was only known for Canada and the United States of America, is extended.