Carlota, a new genus of Agrypnini from the Valdivian Forests of Chile (Elateridae, Agrypninae, Agrypnini)

Abstract Carlota gen. n., with one included species C. coigue sp. n., is described and illustrated from the Valdivian forests of Chile. The relationships of this genus to other Agrypnini from Chile are discussed and generic key for Chilean Agrypninae genera is provided.


Introduction
Up to now, the Chilean Elateridae includes 52 genera and 140 species (Arias-Bohart and Elgueta 2012). The canopy beetle faunas of Nothofagus spp., and Araucarian forests show at least 32 yet undescribed Elateridae taxa (Arias et al. 2008). From those representing unknown Elateridae collected by fogging I found several specimens of a new Agrypnini.

Materials and methods
This study is based on the specimens from multiple collecting trips of the Essig Museum of Entomology, University of California, Berkeley (led by E. T. Arias-Bohart) and private Chilean collections. The type specimens and loan material are indicated in the text. Acronysms of institutions and private collections follow Arnett et al. (1993).
Specimens from which the genitalia were removed were first relaxed in 10% KOH solution over 1 to 3 days.
For examination of the male genitalia, the last abdominal segments were removed and placed in water with a few drops of soap in a Petri dish and left overnight. Then genitalia were subsequently extracted and placed into a small vial with 90% alcohol, or glued on a card, or on a vial, and pinned under the specimen. Methods outlined by Becker (1958) were followed for examination of the female genitalia. After examination, female genitalia were placed in a small vial with glycerin and pinned under the specimen.
Measurements. Following measurements were made with the aid of a calibrated ocular micrometer as follows: total body length from the frontal margin to elytral apex; pronotal length and maximum width of the pronotum, when both sides are in focus, and elytral length and maximum width of the elytra, when both sides are in focus.
Label Information. Places and names of the material studied are from the original spellings from recorded specimen labels. The following symbols are used in the recorded label information as follows: / indicating line separation within label, // indicating label separation. Juan Enrique Barriga's collection labels include the following URL http://www.coleopteraneotropical.org, which I have excluded from the label information.
Drawings were made using a camera lucida on a Leica MZ7 dissecting scope. Type material has been databased with a unique number indicated on the label information consisting of the acronym EMEC and the identification number. For example, the holotype of Carlota coigue sp. n., has the unique number EMEC10005989 followed by the repository in brackets. Type information of the described material is available online at http://essigdb.berkeley.edu.
Etymology. The generic name Carlota (gender feminine) is dedicated to my mother Carlota Tobar Vega, who has always encouraged me in my study of nature and insects.
Description. Body about 3.72-4.22 times as long as wide, sides subparallel from anterior pronotal sides towards elytral sides, slightly narrowing posteriorly towards elytral apices. Dorsal vestiture short dense, fine, with some erect short well distributed hairs.
Prothorax subquadrate, about 0.70-0.90 times as long as greatest width. Sides almost straight or slightly expanded posteriorly, carinate and emarginate, not visible for their entire length viewed dorsally. Posterior angles short and stout, produced posterolateraly. Posterior edge with scutellar notch broad and sharply defined. Disc punctate, clothed with dense hairs. Prosternum more or less flat with deep punctures. Notosternal suture complete, straight for most of its length, open anteriorly; curved posteriorly. Prosternal process narrow near base, then gradually expanded posteriorly, following procoxae in lateral view, extending well behind procoxae. Hypomeron simple, with deep punctures. Procoxae subglobular.
Elytra dark brown or black, about 2.79-3.18 times as long at midline as greatest width and 4.09-4.90 times as long as pronotum. Humeri well developed; parallel-sided anterior 2/3rds, gradually converging posteriorly, apices rounded. Disc with 10 weakly defined puncture rows. Mesoventrite on same plane as metaventrite. Mesocoxae slightly projecting, mesocoxal cavities narrowly separated, open laterally to mesanepisternum. Metacoxae obliquely oriented, with plates not extending to lateral edges of coxae.
Hindwing about 2.83 times as long as wide. Apical field about 0.6 times as long as total wing length, with 2 lightly pigmented oblique linear sclerites. Radial cell well developed, elongate, 3.4 time as long as wide, with inner posterobasal angle forming a right angle. Cross-vein r 3 moderately short, horizontal and arising distally from r 4 , which is mostly linear and complete. Base of RP very long, extending to wing base. R-M loop forming a narrowly acute angle; medial spur slightly curved. Medial field with five free veins. MP 3+4 not branching in 2 veins (Figs 14,16,17).
Prothorax anteriorly black and posteriorly with a reddish triangular area, with long gold semi-decumbent hairs, 1.36 times as long as wide. Punctate, punctures separated by more than one own diameter. Pronotal hypomeron base straight posteriorly.
Scutellum orange at middle. Elytra black or dark brown, 3.04 times as long as wide. Legs brown, vestiture black. Tarsomeres 2 and 4 more or less equal in length, tarsomere 4 only half as long as 1.

Discussion
The subfamilyAgrypninae is considered one the most ancient subfamilies in Elateridae (Gurjeva 1969, Dolin 1978. However, even though several workers have treated this subfamily, its placement within the family is still insufficiently settled since most of the characters used to establish genus-level taxa in more advanced subfamilies of Elateridae show high variability within the Agrypninae at both the generic and specific level (Prosvirov and Savitsky 2011). Hayek (1973) studied the characters to separate the genera of Agrypninae based on the structure of the middle coxal cavity, and was followed by Nakane and Kishii (1956) who also included the size and shape of the second and third antennal segment. Later, Gurjeva (1974) demonstrated the importance of the characters of the prothorax and metathorax, as well as those characters found on the bursa copulatrix as important in establishing natural supraspecific and suprageneric groups. Also, Gurjeva (1974) indicated that the rearward extent of the lateral lobes of the mesosterinite was a subfamily character. I also found important the shape of the lateral lobes of the mesosternite, the shape and depth of the groove of the mesothoracic cavity important.
Carlota appears to be closely related to the genus Candanius because they share the following characters: short antennal grooves, not angulate articulate surfaces of mesososternite (Fig. 11, white arrow). Mesocoxal distances more than four times the mesocoxal diameter, and wing vein MP 3+4 , curves towards major vein MP 1+2 , without branching in two short veins (Figs 16, 17).
Carlota differs from Acrocryptus by the following (contrasting characters for Acrocryptus in parentheses): short antennal grooves not well developed for the reception of the antennae (Fig. 5) (long antennal grooves for the reception of the antennae extending beyond the anterior half of the prosternopleural suture, Fig. 2), lacks grooves on propleura, metasternum and abdominal sternite for anterior, middles, and hind tarsomeres (posses grooves on propleura, metasternum and abdominal sternite for anterior, middles, and hind tarsomeres, Fig. 8), third and fourth tarsal segments without lobes (third and fourth tarsal segments with lobes).
Carlota differs from Dilobitarsus by the following (contrasting characters for Dilobitarsus in parentheses): short antennal grooves not extending beyond the anterior half of the prosternopleural suture, (Fig. 5) (antennal grooves extending beyond the anterior half of the prosternopleural suture, Fig. 6), mesosternal cavity sides anterior half region not parallel, (Fig. 11) (mesosternal cavity sides anterior half region parallel, (Fig. 12), third and fourth tarsal segments without lobes (third and fourth tarsal segments with lobes), wing R cell less than 2 times its width, (Fig. 17) (wing R cell more than 4 times its width, Fig. 18).
Based of the appearance of the prothorax, Hayek (1973) concluded that the retention of Lacon and Dilobitarsus could not be justified. However, I consider these two genera valid based on the following: Dilobitarsus differs from Lacon by the following (contrasting characters for Lacon in parentheses): walls of anterior half of the mesosternal cavity sides mostly parallel (walls of anterior half of the mesosternal cavity sides divergent), posterior region of the mesosternal cavity subquadrate, (Fig. 12) (posterior region of the mesosternal cavity V-shaped, Fig. 13), tarsomeres with lobes (tarsomeres without lobes), bursa copulatrix subglobular (bursa copulatrix globular), sclerotised structure of bursa copulatrix about 0.4-0.5 times the diameter of bursa copulatrix, (Fig. 22) (sclerotised structure of bursa copulatrix about 0.3 times the diameter of bursa copulatrix, Fig. 23).
Discovery of the larvae of the above genera will likely help clarify the systematic position of the tribe Agrypnini and its members.