Bocchus scobiolae Nagy, 1967

Guglielmino, A., Olmi, M., Vári, G., Capradossi, L. & Bückle, C., 2022, Description of the immature and mature larvae of Bocchus scobiolae Nagy (Hymenoptera: Dryinidae), Zootaxa 5195 (4), pp. 361-372 : 362-365

publication ID	https://doi.org/10.11646/zootaxa.5195.4.3
publication LSID	lsid:zoobank.org:pub:236399BC-88DE-4B76-A8FB-322DF177F199
DOI	https://doi.org/10.5281/zenodo.17627347
persistent identifier	https://treatment.plazi.org/id/2E6F87BE-833F-FF90-65A3-F9A1D6D74FCA
treatment provided by	Plazi
scientific name	Bocchus scobiolae Nagy, 1967
status

Treatment

Last immature larval instar (= fourth larval instar)

( Figs 1A, B View FIGURE 1 , 2 View FIGURE 2 , 3 View FIGURE 3 )

Length: 1.1–1.2 mm; width: 0.4–0.6 mm. Body dark brown, only slightly bent ventrad, and covered with discarded exuviae of previous larval instars forming a sac named “thylacium” (sensu Olmi 1994) ( Figs 1A, B View FIGURE 1 ). Anterior region immerged into host’s body, posterior one protruding from intersegmental membranes of host’s abdomen ( Figs 1A, B View FIGURE 1 ). Oral region ( Figs 2 View FIGURE 2 , 3 View FIGURE 3 ) with distinct, but still little sclerified whitish mouthparts, on each side with structure distally forming small oral vesicles and basally containing mandibles, and with finger shaped maxillae. Body with indistinct segmentation. Respiratory system peripneustic, composed of nine pairs of lateral spiracles, one thoracic + eight abdominal. Ventral process absent. During each moult, cuticle breaks along preformed mediodorsal line.

Mature larva (= fifth larval instar)

( Figs 1C View FIGURE 1 , 4–8 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 )

Length: ca. 3.5–4.5 mm. Larva apodous, creamy-white with well-developed head, three thoracic and ten abdominal segments ( Fig. 1C View FIGURE 1 ). Head prognathous, smooth, whitish, well sclerotized, its posterior part retracted partially under first thoracic segment ( Figs 6A–C, E View FIGURE 6 ). Antenna very simple in structure; antennal orbit circular, slightly convex, with two small conical sensilla medially ( Figs 4A View FIGURE 4 , 7A View FIGURE 7 ). Chaetotaxy of head characterized by four pairs of long slender sensory bristles: one pair posteriorly of antennae, one pair in anterolateral position and two pairs in frontoclypeal area ( Figs 4A View FIGURE 4 , 7A View FIGURE 7 ). Other sensory organs represented by small sensory pits: one pair located at midlength of head behind posterior bristles, one pair laterally of each antenna, three pairs near anterior margin, and one pair on anterolateral part of head (not visible from above) ( Figs 4A View FIGURE 4 , 7A View FIGURE 7 ). Frontoclypeal suture indistinct. Anterior margin of clypeus straight ( Figs 4A View FIGURE 4 , 7A View FIGURE 7 ). Labrum large, dorsally convex, apically narrowing and subrounded. Anterior half with two sensory pits and, near anterior margin one row of four long sensory bristles ( Figs 4C View FIGURE 4 , 6A–E View FIGURE 6 , 7B View FIGURE 7 ). Transition region between labrum and epipharynx with four to five short bristles ( Figs 4D View FIGURE 4 , 7C View FIGURE 7 ). Epipharynx with four cone-shaped sensilla in medio-distal region ( Figs 4D View FIGURE 4 , 7D View FIGURE 7 arrows) and thin hair-like setae; setae distally rather long, single or paired, proximally very small and arranged in transverse rows ( Figs 4D View FIGURE 4 , 7C, D View FIGURE 7 ). Mandibles strongly sclerotized, triangular, with broad bases and apical portions pointed and curved in medial direction. Each mandible with long slender sensory bristle near its base ( Figs 4B View FIGURE 4 , 6A–E View FIGURE 6 ). Maxilla weakly sclerotized, each one with maxillary palpus, three long sensory bristles arranged in semicircle near base of palpus and two other ones placed ventrolaterally in its proximal region ( Figs 5A View FIGURE 5 , 8A View FIGURE 8 ). Maxillary palpus subcylindrical, apex with area delimitated by cuticular edge including four sensilla of different size and shape: two (exceptionally three, see Figs 5B View FIGURE 5 , 8B View FIGURE 8 ) uni-articulated, small and cone-shaped and two bi-articulated consisting of long cylindrical basal segment and small cone-shaped apical article; in subapical position one medially placed sensory bristle and laterally one large sensory pit ( Figs 5B View FIGURE 5 , 6F View FIGURE 6 , 8B View FIGURE 8 ). Labium weakly sclerotized, distally with spinneret and subapically with labial palpi ( Figs 5A, C View FIGURE 5 , 6E, G View FIGURE 6 , 8A, C View FIGURE 8 ). Three sensory bristles in semicircle in proximity of base of each palpus. Labial palpus broad and well defined, similar in structure to maxillary palpus, with large proximal sensory pit and four distal sensilla structurally similar to those of maxillary palpus ( Figs 5A, C View FIGURE 5 ). Spinneret with one cone shaped sensillum on each side ( Fig. 5C View FIGURE 5 , arrows), opening apically by transverse slit ( Figs 5C View FIGURE 5 , 6E, G View FIGURE 6 , 8C View FIGURE 8 ).

Thorax and abdomen with sensory bristles, about eight on each side, arranged in transverse rows around each segment; thoracic sensory bristles long and slender (about 80–150 μm), abdominal ones very small (30–40 μm) ( Figs 8E, F View FIGURE 8 ). Tracheal system peripneustic, with 9 pairs of spiracles, of approximately equal size in thorax and abdomen. Atrium of spiracles bulb-shaped ( Fig. 8D View FIGURE 8 ). All spiracles simple, without bristles, hairs or other particular protection structures.