Panorpidae Latreille 1805
Creators: name: Szpila, Krzysztof
name: van de Kamp, Thomas
name: Sontag, Elżbieta
name: Krzemiński, Wiesław
name: Kopeć, Katarzyna
name: Soszyńska, Agnieszka
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Mecoptera
Panorpidae

description: Family: Panorpidae Latreille 1805
Diagnosis: Larva with eruciform body shape, compound eye, mandibulate mouthparts, antenna with swollen pedicels, thor - acic legs four -segmented with triangular tibial lobe, abdominal segments with dorsal annulated processes and eight pairs of abdominal prolegs, dorsal annulated processes on the abdom - inal segments A1–A7 short, dorsal annulated processes on the abdominal segments A8–A10 strong and long, ventral prolegs small.
General morphology of the larva: The larva is eruciform, with three pairs of thoracic legs and eight pairs of abdominal prolegs (Figs 1A, 2A–C, 3A–C); intersegmental membranes of the segments are not clearly visible; the antennae are three - segmented (Figs 2B, 4B, C, 5A, B); mandibulate mouth - parts (Figs 4C, 5B); compound eyes situated dorsolaterally between the vertex and gena (Figs 2B, 3A–C, 4A), the right eye protruding, left eye slightly damaged, flattened (Fig. 4B, C); ommatidia of the right eye are distinctly visible (Figs 2B, 4A); the thoracic segments each bear pairs of four -segmented legs (Figs 2B, 3A, 4A, D), the first thoracic segment features a prominent, prothoracic shield covering the entire dorsal surface of the segment (Figs 2B, 3A, 4D); the abdominal seg - ments are equipped with paired erect subdorsal annulated processes on A1–A9 and a single mid -dorsal annulated pro - cess on A10 (Figs 2A, C, 3A–C, 4E); the respiratory system not visible, but one prothoracic, and one spiracle of the ab - dominal segment A1 present (Fig. 4A, D).
Size: 4.9 mm length.
Head capsule: Head well -sclerotized, width 0.9 mm (Figs 2A, B, 4A–C); the coronal and frontal sutures join together, forming an inverted Y -shaped ecdysial line, with the stem medially extending from the occipital foramen and the lateral arms diverging down - ward to the frontoclypeal suture (Figs 4B, 5A); the anterior and posterior tentorial pits not visible; nine pairs of setae were iden - tified that are distributed on the cranium symmetrically (Figs 4A, B, 5A, B); the slightly trapezoid clypeus is separated from the frons by the distinct frontoclypeal suture, clypeus is subdivided into the basal sclerotized postclypeus and the apical anteclypeus, between postclypeus and antyclypeus is a slightly sunken line with a transverse row of four setae (Figs 4B, 5A).
Compound eyes, antennae, and mouthparts: Eyes with about 30 om - matidia (Figs 2B, 4A); antennae located between compound eye and clypeus (Figs 2B, 3A–C, 4B, C), with three segments: basal scape, pedicel, and distal flagellum (Figs 4C, 5A); the scape is in - serted into the antennal socket supported by a raised antennal sclerite (Fig. 5A, B), flagellum is the longest and more slender than the pedicel and the basal scape; the mouthparts are typ - ical mandibulate type, the labrum trapezoid and slightly notched midapically, and articulated proximally with the anterior region of the clypeus (Figs 4B, C, 5B), with only one pair of long labral setae (outer) (Fig. 4C); the membranous epipharynx barely visible; the paired mandibles strongly sclerotized and curved inward with pointed tips, uniting to the subgena at the clypeal base (Figs 4C, 5B); the mandibles taper toward the apex, with two long, subequal setae visible on their lateral surfaces (Figs 4C, 5B); the paired max - illae each consist of the basal cardo -stipes, galea, lacinia, and a three -segmented maxillary palp (Figs 4C, 5B); the cardo -stipes is kidney -shaped and distally connected to the galea and lacinia medi - ally and bears the palp laterally, setae on the maxillae not visible; the galea broadly connected with the lacinia at the base (Figs 4C, 5B), comparatively small; the maxillary palp inserted on a palpifer, the basal two segments roughly equal in length and shorter than the distal one (Figs 4C, 5B); the labium is greatly reduced in size, ligula absent, most parts of the labium retracted into the capsule, a pair of two -segmented labial palps visible between the cardo -stipes bases (Figs 4C, 5B); the salivary duct spens between the divided prementum; the distal segment of the labial palp much longer than the basal one (approximately 1.5 times) (Fig. 4C).
Thorao: Prothorax with prothoracic shield and paired spiracles and specific chaetotaxy (Figs 2B, 3A, B, 4A, D); the prothoracic shield saddle -like and broad, with several setae along the margin; the prothoracic spiracle situated at the posterolateral corner of the prothoracic shield (Fig. 4A, D); meso - and metathorax similar in morphology and chaetotaxy, and lack of spiracles; the thoracic legs with four segments: coxa, femur, tibia and tarsus (Figs 2B, 4A, D); the triangular tibial lobe present (Figs 2B, 4A).
Abdomen: Abdomen with 11 segments, each segment with short setae on the pinacula and erect subdorsal annulated processes in - serted on stout basal protuberances (Figs 2A, 3A, B); the annu - lated processes paired and moderately long on segments A1–A7, strong and elongated on segments A8–A9 (Figs 2A, C, 3A–C, 4E), the last abdominal segment bears single annulated process on the mid -dorsal line of A10 (Figs 3A–C, 4E); A1–A7 roughly similar to each other in morphology and chaetotaxy (Fig. 1A), A8–A10 have much longer processes, thinner, and differ consid - erably from the others in chaetotaxy (Fig. 3A, 4E, 5C); A1–A8 with paired lateral spiracles and ventral prolegs (Figs 2A, C, 3A, C, 4E); the spiracles barely visible (Figs 2A, C, 4A, E); the stout prolegs unsegmented, and not arranged in a longitudinal line with the thoracic legs (Figs 2A, C, 3A, C, 4E); A11 reduced.
The chaetotaoy: The position of numerous small setae was not possible to detect. The chaetotaxy of the prothorax different from the meso - and metathorax, which are similar to each other (Figs 4D, 5C); the first seven abdominal segments (A1–A7) bear similar chaetotaxy, while terminal segments (A8–A10) in - dividually distinct (Figs 4E, 5C).
Prothorao (T1) (Figs 4D, 5C): Three setae (xd1, xd2, and sd2) along the anterior edge of the prothoracic shield are, one seta (sd1) situated at the posterior edge of shield, seta d1 absent; the distance between xd2 and sd2 slightly longer than that of xd2 and xd1; L1 on the lateral pinaculum, anteroventral to the spiracle; two long setae (sv1 and sv2) on a crescent pinaculum dorsal to the coxal cavity; microsetae on this pinaculum not vis - ible; spiculate ventral seta (v1) not visible.
Meso- and metathorao (T2 and T3) (Figs 4D, 5C): Two clavate setae (d1? or d2?, and sd1) and one microseta (msd1) on dorsal pinaculum; microseta md1 not visible; ventral to the dorsal pinaculum three pinacula, each accompanied respectively by one long seta (sd2, l1, and l2); microseta ml2 present; subventral setae (sv1 and sv2) located on two detached subventral pinacula.
Abdominal segments A1–A7 (Figs 4E, 5C): The annulated pro - cesses short on A1–A7, three setae (d1, d2, and sd1) and one detectable microseta (msd1) on the dorsal pinaculum; ventral to the dorsal pinaculum, another pinaculum accompanied by long seta (sd2); posterior to the spiracle a long lateral seta (l1); L2 located together with ml2 on a lower lateral pinaculum; three setae (sv1–sv3) on two subventral pinacula; ventral setae (v1 and v2) not visible; seta d2 two times shorter than d 1 in length; setae sd1 and sd2 roughly in the same length as l1; setae sv2 and sv3 half as long as sv1.
Abdominal segment A8 (Figs 4E, 5C): The setae on the basal protuberance of the annulated process are not visible; setae l1 and l2 long; subventral pinacula with long setae (sv1–sv3); seta l1 about 1.5 times as long as l2 and markedly shorter than sv1; anteriorly to the ventral prolegs, setae v1 and v2 present.
Abdominal segment A9 (Figs 4E, 5C): The setae on the basal protuberance of the annulated process are not visible; setae l1 and sv1 almost equal in length.
Abdominal segment A10 (Figs 4E, 5C): The setae on the basal protuberance of the single mid -dorsal annulated process are not visible; seta d1 and microsetae msd1 and msd2 well visible; other elements of chaetotaxy are not visible.
description: Published as part of Szpila, Krzysztof, van de Kamp, Thomas, Sontag, Elżbieta, Krzemiński, Wiesław, Kopeć, Katarzyna & Soszyńska, Agnieszka, 2024, The hidden world of fossil larvae: description and morphological insights of an immature scorpionfly (Mecoptera: Panorpidae) from the Baltic amber, pp. 1-11 in Zoological Journal of the Linnean Society 202 (3) on pages 3-6, DOI: 10.1093/zoolinnean/zlae009, http://zenodo.org/record/14291022