Capniidae terminalia

In addition to wing venation and thoracic sclerites (Figs. 53–57, Tables 1–2), the systematics of adult Capniidae is based mainly on the terminalia (Figs. 1–48, Tables 3–5). This study discusses the structure of the male epiproct, paraprocts, and the fusion plate. These structures are directly involved in mating. The general form and associated structures are illustrated in Figs. 1–31. These figures are shown to support new generic diagnoses that are presented. A ventral view of the male terminalia is depicted for all genera examined (Figs. 32–48). Terminology and comments are given below:

Basal sclerite (B-scl): The basal portion of the epiproct that can be divided or fused with the main and the laterobasal sclerites (Ep-scl, Lb-scl). It can be vestigial or lacking; its size is usually typical for the genera (Figs. 1–2, 5–6, 11–22, Table 3). In some genera the B-scl is developed into the Lower limb (Ll) of the epiproct, see below.

Laterobasal sclerite (Lb-scl): One of two lateral sclerites of the epiproct that are positioned caudally to the Bscl and laterobasally to the Ep-scl (see below). It can be divided or fused with both of those sclerites. The size is also typical for the genera (Figs. 1–6, 17–22, Table 3).

Main epiproct sclerite (Ep-scl): The main sclerite of the epiproct, sometimes called the upper limb of the epiproct (Nelson & Baumann 1987). It is open apically, usually divided in its dorsal portion, and can be divided or entire in its ventral and lateral portion; its ventral connection and lateral division are typical for the genera, as are the presence or absence of setae on its basocaudal portion (Figs. 1–22, Table 3).

Lower limb (Ll): An epiproctal sclerite is developed from the B-scl (Figs. 3–6, Table 3). It is large in Utacapnia Gaufin, 1970 and Capnura Banks, 1900, where the B-scl is completely formed into the Ll and the original sclerite is vestigial or lacking. In Allocapnia Claassen, 1928, a small Ll is present on the B-scl but not divided. However, the epiproctal portion previously termed Ll in this genus, is in fact the highly separated lower part of the longitudinally divided Ep-scl. A vestigial Ll also present on the vestigial B-scl fused with the Ep-scl in genus Capnia s.s. and in C. s.l. vidua Klapálek 1904 (Figs. 3–6).

Inner sclerite (I-scl): An epiproctal sclerite that is present in some genera, surrounded by the Ep-scl. It is not connected to the Ep-scl but to the membranes forming the epiproct’s inner funnel that fix the Fp and lead the sperm into the apical opening of the epiproct (Figs. 1–4, 11–18, Table 3).

Eversible crest (Ec): An eversible, membranous portion of the epiproct on its dorsoapical part, connected to the Ep-scl. Its absence or presence is typical for the genera, although it is difficult to recognize in its contorted state (Figs. 1–4, 8–10, 17–18, Table 3).

Fusion plate (Fp): As described by Klapálek (1896), this organ leads the sperm into the epiproct, and it is more or less fused with the paraprocts (Fig. 7, 9). In this study we note the relative length and width of the organ, and its division or fusion with a small basal sclerite, called the Retractoral plate (Rp) by Hanson (1946) (Figs. 23–31, 81, Table 4).

Paraprocts (Pp): The relative length and width of the apical part are typical for the genera, and it is usually related to the dimensions of the Fp (Figs. 32–48, 81, Table 4).

Subgenital plate (Sg): In males, its fusion or division with Sternite 9 (St 9) and through this to Tergite 9 (Tg 9) is typical for the genera. If a ventral vesicle is present, the Sg is always separated from the St 9 that is restricted to a well sclerotized arch connecting ventrobasal corners of Tg 9; the vesicle is located on this arch-like St 9, and not on the Sg (Figs. 32–48, Table 4).

.