Pyrrhopyge charybdis charybdis Westwood, 1852

Carneiro, Mielke, Olaf H. H. & M, Mirna, 2013, Thorax and abdomen morphology of some Neotropical Hesperiidae (Lepidoptera), Insecta Mundi 2013 (327), pp. 1-47 : 5-10

Pyrrhopyge charybdis charybdis Westwood, 1852

Cervix and Prothorax. The cervical sclerite is composed by a pair of T-shaped slim sclerites whose bases are inserted into the episternum. It possesses two pairs of ventral-anterior arms, the dorsal pair is long and connected to the concavity of the tentorial bridge, while the ventral pair is about half the size of the dorsal and does not blend ventrally ( Fig. 1 ). In the second basal quarter of the dorsal arm, there is a well developed sensitive cervical organ ( Ehrlich 1958a), containing relatively long bristles, and denominated cervical organ.

The first thoracic segment is reduced to small sclerotized areas within the pleural membrane, anteriorly delimited by the cervical sclerite and posteriorly, near the spiracle, by the scutum II and the episternum II. The notum has two lateral plates and a dorsal plate ( Fig. 1 and 5), the latter being lobular, posteriorly elongated and dilated on the posterior margin, presenting a distinctly sclerotized central line, bifurcated on the middle, forming a distinctly melanized triangular posterior area. The lateral plates are anterior-posteriorly flattened, reaching the apical portion of the episternum.

Posteriorly, the patagia form slightly bulging sclerotized lobes between the head and the thorax, articulated on two points with the dorsal prothoracic membrane, and carry scales that cover all the cervical-prothoracic area. Likewise, the parapatagia, which are also sclerotized, are located over the membrane and extend lateral-ventrally towards up to near the first thoracic spiracle, which is elongated and located on the pleural membrane. The surface of the parapatagia presents two bands with distinct sclerotization and texture, the anterior is rugged and slightly translucent, and the posterior is more melanized, hard and smooth, without insertion of scales. Additionally, a pair thin bars, parallel to the parapatagia, is found on the posterior limit of the dorsal membrane of the prothorax, anteriorly to the prescutum II and the scutum II ( Fig. 5). Most likely, due to its frailty and difficulty in visualization, no mention of this structure by other authors was found.

The episternum I is oval, ventrally delimited by the articulation with the trochantin, and dorsally by a slightly more melanized region that is also distinct, which is connected to the lateral bar of the pronotum. Its lateral-posterior portion presents an internal crease, which might be a manifestation of the pleural suture of the epimeron I or can be characterized as a simple crease of the episternum (also visualized in the mesothorax). The trochantin I ( Fig. 1 , 9 and 62 ), a small elongated structure which is also near the preepisternum, is located between the coxa and the episternum.

Anteriorly, the preepisternum I forms a convex shield anterior-ventrally to the episternum I, and is ventrally projected as a slim extension which is posteriorly connected to the furca I. Ventrally ( Fig. 9 ), this structure forms a triangular plate, where there is a unique concavity, which forms two internal apophyses for the adhesion of thoracic muscles responsible for part of the leg movement. It is posteriorly connected to the spina I, which connects the prothoracic segment to the metathoracic one via two long structures, forming an articulation similar to a spring. This mechanism allows all of the tagma to be adhered to the mesothorax, offering more support to a segment that is formed, to a great extent, by membranes. Posteriorly, it is articulated to the paraepisternum II through small slim articulations.

Mesothorax. The notum II is divided into four sclerites: prescutum II, scutum II, scutellum II and postnotum II. The first forms a triangular structure (in dorsal view) blended to the scutum by the prescutoscutal suture ( Fig. 13 ). Laterally, its view is blocked by the anterior-lateral development of the scutum II and by the concavity of its anterior-ventral margin ( Fig. 17 ). The scutum II covers great part of the thorax, and forms an elongated dorsal hemispheric capsule that laterally presents three apodemes and a sulcus along each side of the weak mesoscutal suture. A pair of oblique sulci occurs medianlaterally, which might be related to movement and/or support of the tegulae. Posteriorly, the W-shaped scutoscutellar suture II separates the scutum II from the scutellum II, posteriorly giving a bilobed appearance to the former.

Laterally-ventrally, three processes surge for the articulation with the axillary sclerites, two from the scutum II (anterior and median) and the other from the scutellum II (posterior). The anterior one, the anterior notal process II is wide, strongly developed towards the subalare and separated from the scutum by an evident suture. The smaller median notal process II, composed of a bidentate projection, with the posterior apophysis which is more developed and anteriorly projected, under the small anterior dentation. The posterior notal process II, originating from the anterior arm of scutellum II, forms a simple and small expansion and its internal portion connects to the median process via a suture that is not visualized laterally, nor is it mentioned in any morphological descriptions from the literature. The median notal process II, which is difficult to visualize, is sometimes omitted in a few illustrations found in the literature.

The scutellum II, which is imbedded between the scutum II and the postnotum II, reaches the posterior portion of the thorax, dorsally covering the scutum III and the postnotum II itself, which is ventrally hidden ( Fig. 17 ). Lateral-anteriorly, two parallel arms meet the post-wing portion of the epimeron II and the anterior arms of the postnotum II. The axillary cord II rests along this arm. The phragma II, which is blended to the postnotum II, extends ventrally-posteriorly (entering part of the first abdominal segment) as a convex shield where muscles responsible for moving the wings are inserted. Its surface contains tegumental creases which dorsally blend to the internal creases of the scutum III.

The subtegula is elongated, dorsally circling the basalare II, located on the pleural membrane, between the anepisternum II and the anterior notal process of the wing. Posteriorly, the subalare II plate is well developed and completely surrounded by the pleural membrane. Its anterior-posterior ends are sharpened and separated, in the median area, by a transversal suture. The tegulae, located dorsal-laterally to the mesothorax, form mobile lobed structures, articulated to the subtegula by a circular orifice located on its inferior face ( Fig. 21 ), where a short median suture is originated, although not observed in the other species.

The anepisternum II is approximately square-shaped ( Fig. 54 ), and partially blended to the katepisternum II through the anepisternal suture II, which has approximately 3/4 of the width of the katepisternum II. Dorsally, it presents a tegumental crease that is directed towards the interior of the body. The longer katepisternum II is ventrally extended, and is partially blended to the basisternum II due to the presence of an incomplete and apically curved paraepisternal suture II ( Fig. 9 ). The anterior portion of the katepisternum II is arched towards the internal part of the body and it is weakly delimited by a suture, especially on the dorsal-anterior portion. The paraepisternum II is triangular, presenting a small invagination on the median-posterior region so that it can articulate with the spina I.

The marginopleural suture II is short, originating on the coxal suture and directed towards the basisternum II, ending at the discrimen II. The basisternum II is triangular, dorsal-ventrally flat, longitudinally sectioned by the discrimen II. It tapers off posteriorly into a median crest, which connects itself internally with the furca II projections (both diagonally project themselves inside the body and blend with the postalare region of the epimeron II). In the ventral portion of the furca II, there are a pair of small projections, the coxal ventral articulations II, which are responsible for the connection of the internal margin of the coxae II to the pleural sclerites. Coxopleural articulations II are visualized through a depression on the dorsal portion of the eucoxa II and the meron II, connected to the basicostal suture.

The epimeron II is irregular, possessing a membranous dorsal portion and an anterior membranous transversal lobe projected on the epimeron II, which, in lateral view, covers a narrow extension parallel to the pleural suture II of the epimeron II, itself ( Fig. 17 ). Posteriorly, its dorsal margin is undulated. There is an additional tegumental crease, directed towards the inside of the body (which connects ventrally to the furca II projection), and there is yet another small triangular membranous portion ventrally, next to the meron II.

Metathorax. It is similar to the mesothorax, basically being made up of the same structures, though different in shape and size. Two concave triangular plates, median-posteriorly connected by a thin extension, form the scutum III, located lateral-ventrally to scutellum II. It presents two ventral projections directed towards the pleural membrane: anterior notal process III and posterior notal process III ( Fig. 25 ).

The scutellum III and the postnotum III are anterior-posteriorly flat, and precede the first abdominal tergum. Lateral extensions of the scutellum III, which support the axillary cord III, stretch out parallel to scutum III, while the postnotum III extends laterally along the epimeron III. The basalare III is small and thin, and offers support to the hind wing.

The anepisternum III, which is separated from the katepisternum III, is oval and hides the spiracle II. The katepisternum III is semi-trapezoidal and ventrally-anteriorly separated from the paraepisternum III by the paraepisternal suture, as well as by a tegumental crease that fixes this structure to the other anterior sclerites of the mesothorax. A crest on the internal side of the katepisternum can be seen by transparency, dorsally-ventrally crossing the katepisternum III, where a bundle of muscles directed towards the hind wing is attached to it. Perpendicular to the pleural suture III, there is the complete marginopleural suture, forming a triangular sclerite right above the eucoxa III ( Fig. 25 ). Ventrally, there is no suture that separates the katepisternum III from the basisternum III ( Fig. 9 ).

The epimeron III is geometrically similar to the epimeron II and ventrally presents a longitudinal suture that separates it from a narrow triangular sclerite, which contains a non-sclerotized ventral portion. Such a division of the epimeron III was not found in any other species ( Fig. 25 ).

Legs. The anterior pair is smaller, without any modifications or reduction of sclerites in any of the five articles. They do not present a basicostal suture. The coxa I is long and tubular, with a slightly wider base, without any evident articulation points on its internal dorsal margin ( Fig. 29 ). The articulation zone with the trochantin I does not present any evident differentiation. The trochanter I is triangular, small, and presents a dorsal concavity. The femur I is tubular and a little longer than the coxa. The tibia I is less than half the length of the femur I, and is provided with a baton-shaped, internally curved, median epiphysis, which is probably related to the antenna cleaning behavior ( Fox, 1967). The tarsus I is composed of five tarsomeres, the proximal one being larger than the others (by around six times). The fourth tarsomere is smaller in males and even smaller in females. Along the entire tarsus, three series of ventral thorns of different sizes are present. The last tarsomere presents few and small lateral-ventral spines, has almost no scales and is provided with a pair of sensitive bristles at its apex area.

The other pairs of legs maintain basically the same aspect, though the coxae II and III are subdivided into eucoxa II and III (anterior ones) and meron II and III (posterior ones) by the basicostal suture II and III, respectively. They are slightly curved and dorsally contiguous to the pleural sutures II and III ( Fig. 17 , 25 respectively). These coxae are conical, a little shorter than the anterior coxae, unlike tibias II and III, which are longer on the mesothoracic and metathoracic legs (comparatively to the femurs) and possess spurs at the same position as the epiphysis on tibia I, a pair of mesothoracic apical spurs on tibia II and a pair of apical spurs plus a pair of mesothoracic subapical spurs on tibia III, all of which are asymmetrical ( Fig. 29 ).

The distitarsus is similar in all legs, presenting arolium, pulvilli, and tarsal claws intermingled with the unguitractor plate, which is cylindrical and short. The arolium is connected to unguitractor plate by a fan shaped and vertical stretched peduncle, which is apically dilated. The tarsal claws are bifid, presenting a curved and needle-like apical projection, while the base is truncated next to the pulvillus, which is also bifid and presents small bristles ( Fig. 58 ).

Wings. Triangular mesothoracic wings presenting fourteen longitudinal veins, of which only the 3A vein does not extend up to the margin ( Fig. 33 ). The costal vein (C) extends from its insertion at the base until it anastomoses with Sc ( Fig. 39 ). In the remaining costal portion of the wing, its presence is dubious and deserves detailed histological studies. The Sc vein freely originates on the base of the wing without branching, ending a little over half the length along the costal margin. The radial vein also parallel to coastal margin and super-exposed at its base, has all its branches differentiated starting from the main branch, except for M1, which, in males, is originated next to the bifurcation of R4 and R5, while in females its origin lays anteriorly.

The discal cell is elongated ( Mielke, 2001), longer than the anal margin or more than 2/3 of the size of the costal margin. At its apex there is a thin and small prominent vein (dcs) which is joined to the base of the M1 and then branches in the medial portion of the M2 vein. The dcm vein is slightly longer than the dci, making the origin of M2 closer to M3 than to M1. The dcm and dci veins are barely visible and completely close the discal cell on its distal margin. In the posterior area, the 2A and 3A veins originates independently at the base of the wing, the latter blending with 2A near the first ramification of the cubital vein.

The metathoracic wings present softer angles and only eight longitudinal veins. The costal vein provides structure to the humeral angle, continuing towards the bifurcation of Sc and R. It is dorsally adorned of differentiated scales that are similar to those on the ventral anal area of the mesothoracic wing ( Fig. 42 and 43 ). Sc, R, and CuA originate from a single branch, after which the first vein to diverge is the Sc+R1 which extends to the apical angle of the wing. Rs is also parallel to the costal margin and originates from the base and from the Sc+R1, bifurcating from M1 before the apex of the discal cell. The CuA vein is similar to the forewing. However, the dcm vein does not originate from M2, which is absent. The 2A and 3A veins are again separated at the base and end at the anal angle of the hind wing. There is no evident humeral vein, though there is a small projection directed towards the base.

Abdomen. It is thick and fusiform, and is represented by ten segments. Due to the reduction of the last two or three segments to form the genitalia, only eight segments in males and seven in females are visible ( Fig. 66 and 67 ). The number of segments follows the number of spiracular orifices in the pleural region, the first pair being relatively more developed than the others, and partially covered by the tergal lobe. There is no spiracular orifice in the eighth abdominal segment of males.

Anteriorly, the tergal lobe is characterized as a circular evagination of the membrane, which is slightly sclerotized and projected over the first spiracle (its location may be influenced and effected by the specimen preparation). The prespiracular bar is thin and articulated to the sternum by a small ventral concavity that separates it from the anterior-lateral apodeme of the first sternite. Dorsally, the prespiracular bar does not reach the tergopleural bar. Likewise, the postspiracular bar, which is reduced to a lateralventral extension of the second tergum, does not reach the dorsal margin of the sternum. Over the first tergum there is also a bar (tergopleural bar), which is blended to the anterior-lateral margin of the second tergum and responsible for the sclerotized integumental connection between the abdomen and the thorax. Longitudinally, the tergopleural sulcus traverses the tergopleural bar, which is positioned ventrally to the first tergum.

The first tergum is anterior-posteriorly compressed between the thorax and the second tergum, which gives it a scale-like shape ( De Jong et al. 1996; Ackery et al. 1999; Mielke 2001). In the first and second sterna (topographically blended sclerites) it is possible to see a small median ventral prominence similar to a keel, which gradually disappears posteriorly on the other abdominal sterna.

The subsequent terga are partially juxtaposed to the posterior ones, following the schematic aspect of secondary sclerotization proposed by Snodgrass (1935). The entire dorsal-distal tergal portion located on the posterior tergum is membranous. The sterna do not present such a conformation.

The other pregenital segments, although basically similar, do not present specializations or substantial changes in their external morphology, except for the last one (eighth in males and seventh in females), which presents significant differences, including sexual dimorphism. The pregenital segment presents a tergum provided with a membranous posterior invagination, which is semicircular in males and C-shaped in females ( Fig. 74 to 77). The sternum is distinctly reduced in males to a small sclerotized thin bar, while in females it is rectangular and has round edges. There is a thick spot on the posterior margin of the terga where long bristles, which reach the base of the genitalia, are inserted.

Male Genitalia. The two terminal segments of the male are modified for the formation of the genitalia, the ninth tergum corresponding to the tegument, the sternum to the saccus, and the tenth to the uncus and the gnathos. Dorsally, the tegument forms a bulging structure on the dorsum, provided with posterior-lateral bifid apophyses, which are developed, strongly sclerotized and projected in parallel towards the uncus, which is also bifid ( Fig. 98 ). Ventrally, a M shape membranous orifice can be seen on the uncus. The gnathos can be observed as being composed of a pair of triangular parts glued to the membrane and presenting a thin longitudinal expansion that gives ventral support to the anal orifice. The fultura inferior is distinctly developed on a lobular plate, flattened on the median-frontal area and present a strong dorsal depression, which is responsible for supporting the aedoeagus ( Fig. 102 ).

The saccus is anterior-dorsally projected as a lobe, reaching about half way up the ninth segment. It is curved parallel to the basal portion of the valva, containing a small lobe over it ( Fig. 90 ). The lateraldorsal projections of the saccus continue until they blend with the tegument, on its lateral-ventral projections.

The valva is well developed, somewhat bulging, anteriorly narrow, dilating posteriorly to the insertion point of the tegumen. The harpe covers all the internal apical face of the valva, slightly pointed posteriorly until it reaches a round apex which is provided with a cluster of relatively long bristles; its dorsal margin is full of small spines, as well as an evaginated arm sheltered between it and the large basal portion of the valva, forming a crease in the median portion of the valva. The homology of this crease with the ampulla described by Sibatani et al. (1954) is discredited, once this crease originates directly from harpe. In the median area of the valva there is also an almost oval-shaped internal orifice, from where the membranous creases inside the valva are viewed. The costa is represented by a posterior crease of the valva, next to the harpe, which is absent on the dorsal margin of the valva. The sacculus is well developed and surpasses more than half the height of the entire valva ( Fig. 91 ).

The aedoeagus is relatively small and thin ( Fig. 106 ). Anteriorly to the opening of the ejaculatory duct there is the coecum penis, which is developed, semi-oval, and slightly curved dorsally to the right. The ejaculatory bulb is globular and membranous. On the opposite end, there is a small triangular crease turned to the right ( Evans, 1951), which presents small apical spines and covers the base of the vesica, which is oval, long and does not present cornuti.

Female Genitalia. Composed by the eighth, the ninth, and the tenth abdominal segments, the whole female genitalia forms two main structures: the isolated eighth sternum and the anal papilla (represented by the ninth and tenth segments). The former is surrounded and sustained by the strong sclerotization of the vaginal lamellae, which, in this case, form a tubular sterigma, where three extensions are present in its opening, two aculeate dorsal ones, and a truncated ventral one ( Fig. 110 and 114 ). It is possible to observe a great variation in these extensions of the sterigma, which need further studies in order to infer about its importance in the differentiation of species or populations.

Laterally to the sterigma duct there is another pair of strongly sclerotized and pointed spines that reach about half the length of the duct, and are fixed to an also sclerotized lobe which is laterally articulated to the duct. Dorsally, the arched projection of the sterigma reaches the ventral portion of the anal papilla and possesses an apically circular orifice whose function is yet unknown. The eighth tergum occurs anterior-dorsally, and is distinctly reduced and almost completely blended to the dorsal portion of the sterigma.

From the duct of the bursa, a dilatation is developed anteriorly to the body that is denominated cervix of the bursa, which precedes the bigger, oval, completely membranous and without signa dilatation, which is the denominated corpus of the bursa. It was not possible to observe the presence of spermatophores among all the specimens observed. The anal papilla corresponds to two lateral plates which together form a cylinder external to the anal (dorsal) and vaginal (ventral) orifices and are apically covered by several bristles.

Figures

Figures 1-4. Lateral view of cervical sclerite and prothorax. 1) Pyrrhopyge charybdis charybdis; 2) Urbanus teleus; 3) Pyrgus orcus; 4) Synapte silius.

Figures 9-12. Ventral view of cervix and thorax. 9) Pyrrhopyge charybdis charybdis; 10) Urbanus teleus; 11) Pyrgus orcus; 12) Synapte silius.

Figures 58- 65. Lateral view of last tarsomere and pretarsum I (Fig. 58 to 61), and trochantin I (Fig. 62 to 65). 58, 62) Pyrrhopyge charybdis charybdis; 59, 63) Urbanus teleus; 60, 64) Pyrgus orcus; 61, 65) Synapte silius. a: trochantin I.

Figures 13-16. Dorsal view of mesothorax and metathorax. 13) Pyrrhopyge charybdis charybdis; 14) Urbanus teleus; 15) Pyrgus orcus; 16) Synapte silius.

Figures 17-20. Lateral view of mesothorax. 17) Pyrrhopyge charybdis charybdis; 18) Urbanus teleus; 19) Pyrgus orcus; 20) Synapte silius.

Figures 21-24. Lateral view of internal surface of tegula. 21) Pyrrhopyge charybdis charybdis; 22) Urbanus teleus; 23) Pyrgus orcus; 24) Synapte silius.

Figures 50- 57. Lateral view of anepisternum II (Fig. 50 to 53) and coxopleural articulation II (Fig. 54 to 57). 50, 54) Pyrrhopyge charybdis charybdis; 51, 55) Urbanus teleus; 52, 56) Pyrgus orcus; 53, 57) Synapte silius.

Figures 25-28. Lateral view of metathorax. 25) Pyrrhopyge charybdis charybdis; 26) Urbanus teleus; 27) Pyrgus orcus; 28) Synapte silius.

Figures 29-32: Internal surface of prothoracic, mesothoracic and metathoracic legs (left to right). 29) Pyrrhopyge charybdis charybdis; 30) Urbanus teleus*; 31) Pyrgus orcus; 32) Synapte silius*. *External surface illustrated.

Figures 33-36. Dorsal view of clarified mesothoracic and metathoracic wings of males (left) and females (right). 33) Pyrrhopyge charybdis charybdis; 34) Urbanus teleus; 35) Pyrgus orcus; 36) Synapte silius.

Figures 37- 41. Details of wings of some observed Hesperiidae. 37, 38) Pyrgus orcus; 39, 40) Synapte silius; 41) Urbanus teleus. a. costal fold; b. costal fold without protection scales (Barth 1960); other letters refer to vein terminology.

Figures 42- 49. Details of wing-coupling mechanism viewed on ventral mesothoracic wingbase (left) and dorsal metathoracic wingbase (right). 42, 43) Pyrrhopyge charybdis charybdis; 44, 45) Urbanus teleus; 46, 47) Pyrgus orcus; 48, 49) Synapte silius.

Figures 66-69. Lateral view of male (Fig. 66 and 68) and female (Fig. 67 and 69) abdomens. 66, 67) Pyrrhopyge charybdis charybdis; 68, 69) Urbanus teleus.

Figures 74-89. Dorsal view from last tergum (two left columns) and ventral view from sternum (two right columns): 74 to 77) Pyrrhopyge charybdis charybdis; 78 to 81) Urbanus teleus; 82 to 85) Pyrgus orcus; 86 to 89) Synapte silius.

Figures 98-105. Dorsal (left) and ventral (right) view of ninth and tenth tergum of male genitalia. 98) Pyrrhopyge charybdis charybdis; 99) Urbanus teleus; 100) Pyrgus orcus; 101) Synapte silius. 102-105. Posterior view of fultura inferior. 102) Pyrrhopyge charybdis charybdis; 103) Urbanus teleus; 104) Pyrgus orcus; 105) Synapte silius.

Figures 90-97. Lateral view of external surface of male genitalia (left), and internal surface of valvae (right). 90, 91) Pyrrhopyge charybdis charybdis; 92, 93) Urbanus teleus; 94, 95) Pyrgus orcus; 96, 97) Synapte silius.

Figures 106-109. Different views of the penis: left lateral, right lateral, ventral and dorsal views (top to bottom). 106) Pyrrhopyge charybdis charybdis; 107) Urbanus teleus; 108) Pyrgus orcus; 109) Synapte silius.

Figures 110-113. Lateral view of eighth, ninth and tenth segments which form the female genitalia 110) Pyrrhopyge charybdis charybdis; 111) Urbanus teleus; 112) Pyrgus orcus; 113) Synapte silius.

Figures 114-117. Ventral view of female genitalia. 114) Pyrrhopyge charybdis charybdis; 115) Urbanus teleus; 116) Pyrgus orcus; 117) Synapte silius.