Leptideini (Leptidea)

Castro-Gerardino, Diana Jimena & Llorente-Bousquets, Jorge, 2017, Comparative exploration of antennae in Pseudopontia, and antennal clubs of the tribes Leptideini and Dismorphiini (Lepidoptera: Pieridae), Zootaxa 4347 (3), pp. 401-445 : 415-416

publication ID	https://doi.org/ 10.11646/zootaxa.4347.3.1
publication LSID	lsid:zoobank.org:pub:610C16FC-0583-4325-B264-6D768E48BC88
DOI	https://doi.org/10.5281/zenodo.6002160
persistent identifier	https://treatment.plazi.org/id/4F018817-FF8C-145E-FF09-FF51D85CFA34
treatment provided by	Plazi
scientific name	Leptideini (Leptidea)
status

Treatment

We studied the following species (see the appendix): L. amurensis amurensis , L. amurensis emisinapis , L. darvazensis , L. duponcheli , L. gigantea , L. juvernica , L. morsei morsei , and L. sinapis sinapis .

ANTENNAL CLUB: In Leptideini the length of the antenna is considerably less than one-half the length of the forewing costal margin; the club is pyriform and slightly flattened ( Higgins 1975) ( Figs. 1A View FIGURE 1 and 6B View FIGURE 6 ). Regardless of the number of antennomeres, the scaleless club is longer in females than in males, especially in L. gigantea where the club of the female is almost twice the length of the male ( Figs. 6C, D View FIGURE 6 ).

ANTENNOMERES: The number of scaleless antennomeres is four to ten and may be the same number for both sexes: L. amurensis (4–5), L. darvazensis (4), and L. duponcheli (5–6); or one more in females (4 in the male; 5 in the female): L. morsei , L. juvernica , and L. sinapis . L. gigantea deviates from this pattern with 6 in the male and 10 in the female ( Figs. 6C, D View FIGURE 6 ). On the dorsal surface, the scaled area extends another two antennomeres in L. darvazensis ; reaches an additional antennomere in L. amurensis , L. duponcheli , and L. morsei ; and occupies an equal number of antennomeres as the ventral surface in L. sinapis and L. juvernica . The distal two or three antennomeres are fused (male of L. duponcheli , female of L. gigantea ), sometimes with an incomplete suture, especially on the dorsal surface. The last antennomere is almost twice as long as the preceding one, and sometimes the two or three distal sulci are separated or fused into a single long sulcus ( Fig. 6B View FIGURE 6 ). The basal antennomere is very wide and depressed, and the ratio in length or amplitude (l:a) is 1:5 ( Figs. 1A View FIGURE 1 and 6B View FIGURE 6 ). In L. gigantea this ratio is on average 1: 2 in both females and males ( Fig. 6C, D View FIGURE 6 ). The antennomeres are barrel-shaped (doliform), depressed, and flat. The proximal edge is wider, so the club is progressively reduced in amplitude ( Fig. 6B View FIGURE 6 ). In L. gigantea , although they are also barrel-shaped, they are much less depressed and their amplitude is constant; for this reason they are more like those of Dismorphiini ( Fig. 9B–D View FIGURE 9 ). The distal antennomere is slightly flattened and cupuliform with the most acute apex in some cases, where there is a ridge (male of L. amurensis ). In L. gigantea the last antennomere is also cupuliform but not flattened; in the male it is short, whereas in the female it is elongate ( Fig. 6C, D View FIGURE 6 ).

SULCI AND PSEUDOSULCI: Species of Leptidea possesses the trisulcate configuration (one central and two lateral or lateral-dorsal surface) but in some cases, the sulci are absenting in the first scaleless antennomere of the club ( L. duponcheli and females of L. gigantea , L. juvernica , and L. a. amurensis ) ( Fig. 1A View FIGURE 1 ). The number of central and lateral sulci is variable but does not always correspond to the number of antennomeres: L. amurensis (male: 3– 4 central and 8–9 lateral; females: 4 central and 8–9 lateral), L. darvazensis (males: 4 central and 8–9 lateral; females: 4 central and 9 lateral), L. duponcheli (4–5 central and 7–8 lateral), L. morsei (males: 3–4 central and 8 lateral; females: 4 central and 7–8 lateral), L. sinapis (males: 3–4 central and 7–8 lateral; females: 2–3 central and 7–8 lateral), and L. juvernica (3–4 central and 8 lateral). In L. gigantea the male has six central and eight lateral sulci, but these extend to the dorsal surface forming a continuous band like on the ventral surface ( Figs. 6C View FIGURE 6 and 9B View FIGURE 9 ); the female shows the highest number of central and lateral sulci of Leptideini (9–10 central and 18 lateral). They occupy more than three-fourths or the entire length of the antennomere, continuous with the anterior and posterior sulci ( L. sinapis , L. morsei , and L. juvernica : a true groove); in L. gigantea the central sulci occupy less than one-half the length of the antennomere ( Fig. 9B, C View FIGURE 9 ). They may be truncated vertical-elliptical ( L. sinapis , L. morsei , and L. juvernica ), but most are irregular. They also may be disaggregated (females of L. duponcheli and L. gigantea ) or aggregates of irregular outline and accompanied by several pseudosulci ( L. amurensis and L. darvazensis ). In the male of L. gigantea the central sulci are strongly truncated aggregates and semi-elliptic ( Fig. 12A View FIGURE 12 ). The lateral sulci are transverse or almost rectangular semi-elliptic and occupy one-half or less of the length of the antennomere; like the central ones, they can also appear disaggregated. In L. darvazensis and L. juvernica , they are practically hidden in the distal antennomere. They extend to the dorsal surface from the second antennomere without flakes of the club ( L. darvazensis , L. sinapis , L. amurensis females, L. morsei males, and L. juvernica females) or third antennomere ( L. duponcheli , males of L. amurensis , females of L. morsei , and females of L. sinapis ). Only in the males of L. juvernica and L. gigantea do the lateral sulci have a lateral-dorsal surface position from the first antennomere.

MICROTRICHIA: We found microtrichia m1, m2, and m4. Within the sulci they fuse with the elliptical cuticular ring of the trichoid sensilla. Within sulci, the ratio of sensilla to microtrichia (st:m) is usually 1:2, 1:3 or 1:4. In the first partially scaled antennomere ( L. duponcheli ), the m2 are flatter, larger, have fewer striations, and are more separated from each other. In the antennomeres union, m2 are shorter, almost smooth, and sometimes with a toothed apex.

TRICHOID SENSILLA: These sensilla are 14–29µm in length, usually shorter than the chaetic sensilla and longer than the basiconic sensilla. A cuticular ring surrounds them, and their stalk is inclined, pointing toward the apex of the sulcus that contains them. The bases of these sensilla are smooth or have sinuous tufts of cuticle, or the stalk appears to be embedded within a darker socket. In the cuticular wall there are some short striate and near them, a few tiny pores. The cuticular rings are partially fused with type 1 microtrichia (m1). In the male of L. juvernica , several excrescences or ornaments are present in the sulci as in Pseudopontia paradoxa , but packed more tightly due to the smaller space between the microtrichia ( Fig. 13B View FIGURE 13 ). In the female they are very rare. In the females of L. sinapis and L. gigantea , some of the trichoid sensilla are bifurcate from the middle or the distal one-third of the stalk.

BASICONIC SENSILLA: Basiconic sensilla are scattered outside the sulci, although they are not abundant. In the female of L. gigantea a few basic branched sensilla end in three apices; this structure does not occur in other species.

AURICULATE SENSILLA: Like basiconic sensilla, we found these outside the sulci in the scaleless antennomeres of the club; chaetic sensilla are abundant in Leptidea .

CHAETIC SENSILLA: In Leptidea there are the chaetic sensilla type 1 (sq1), which have an average length of 25µm ( Fig. 15B View FIGURE 15 ). In L. gigantea and female L. duponcheli we found shorter sensilla that usually do not exceed 20µm, whereas the rest of the sensilla are between 20 and 30µm. The chaetic sensilla in L. gigantea are frequently as long as the trichoid or only slightly shorter. Usually, there are six to ten per antennae on the ventral surface, located toward the middle between the central sulcus and the lateral sulci; also, there is always one under the latter. In L. gigantea they are in the upper half of the antennomere, on the periphery of the sulci, and do not always retain the typical lateral or lateral-mesial distribution of other species; they may be found within some central sulci. In the female they also exhibit a heterogeneous and random distribution. On the dorsal surface they are in the middle area of the antennomeres and are often more abundant in the apex of the last antennomere, except in L. gigantea where they are scarce.

COELOCONIC SENSILLA: These sensilla are more abundant on the dorsal surface of the antenna, usually scarce on the ventral surface and located toward the lateral surface of the antennomere, near the sulci lateral. Two types of sensilla were observed: type 1 (sc1) and type 2 (sc2) coeloconic sensilla ( Fig. 14A–C View FIGURE 14 ). In L. sinapis , L. a. amurensis , and L. darvazensis the two types can be found in pairs. In L. gigantea , only the female has coeloconic sensilla sc1.

OTHER SENSILLA: Unidentified sensilla 1 (sni1) occur in groups at the apex of the distal antennomere (female of Leptidea juvernica ) ( Fig. 16B View FIGURE 16 ). Unidentified sensilla 2 (ni2) is more common on the dorsal surface of the first scaleless antennomere of the club, but in L. gigantea it may be on the ventral side of the distal antennomere. Unidentified sensilla 3 (ni3) are at the apex of this antennomere ( Fig. 16D View FIGURE 16 ). The same types of sensilla were not always documented in all species because sometimes it was not possible to capture images of the dorsal surface of the antennae where sensilla may be confined to that region.

PORES: Pores are found throughout the antennal club, although they are only visible when the microtrichia are separated.