Gryllus sp.

Herhold, Hollister W, Davis, Steven R, Degrey, Samuel P & Grimaldi, David A, 2023, COMPARATIVE ANATOMY OF THE INSECT TRACHEAL SYSTEM PART 1: INTRODUCTION, APTERYGOTES, PALEOPTERA, POLYNEOPTERA, Bulletin of the American Museum of Natural History 459 (1), pp. 1-184 : 1-184

Gryllus sp.

“Field cricket”

Figure 58 (lateral), 59 (dorsal), 60 (ventral)

Plates 35 (lateral), 36 (dorsal), 37 (ventral)

The prothorax features a cagelike network referred to as a “pronotal rim” (prt) by Ander, which we interpret here as T1-DVi.

DESCRIPTION: HEAD: Three paired trunks extending into head: H-DCT and H-VCT present, with additional ventral H-VLT branch from prothorax. Head branches highly networked and cagelike, with multiple dorsal-ventral and lateral connections, making assessment of homology challenging. Mouthparts, H-Ant, and H-Oc determined, but remaining tracheae are highly networked and not homologized here. Readers are referred to online digital models for interactive viewing and further research.

THORAX: T2-S positioned just posterior of foreleg with split opening, typical T2-S dorsal and secondary T2-VS ventral. T2-S with four branches: H-DCT, H-VCT, T2-DB, T2-VB. H-DCT thick, extending dorsad and medially, curving anteriad and extending into head; T1-DVi branching laterally and dorsad from H-DCT close to dorsal margin of T2-S, dividing into cagelike network of T1-DVi tracheae along pronotal wall. H-VCT with short T1-Cx running just anteriad of spiracular opening, extending anteriad and ventrally into forecoxa with multiple branches in a cagelike network similar to pronotum. H-VCT extends medially, curving anteriad and extending into head; T1-AL running ventrad at this curve. T2-DB runs dorsad, curving medially and ventrad as start of T2-DLT, T2-AWL extending laterally and dorsad near this curve, bifurcating into T2-Wbr posteriad and T2-AL ventrad, extending posteriorly toward T3-S; fanlike tracheae extend posteriorly from T2-DB, likely into flight muscles. T2-Wbr with T2-W-c-r branching dorsad into wing, while T2-Wbr continues ventrad, connecting with T3-DB. T2-VB runs ventrad, linking with T2-VLT; similar to T2-DB, fanlike flight muscle tracheae extend posteriorly from T2-VB. T2-VLT running posteriad, with T2-VC2 possible. T1-AL with posterior branch extending into forecoxa and linking with T2-Cx network; anterior branch running dorsad into prothorax. Multiple expanded visceral tracheae along venter; T1-VC possible but networked morphology makes homologies uncertain. T2-VS thick, extending directly mediad as T2-VC, meeting at midline with circular T2-Sept present; see figure 61 for internal cut-away view showing medial septum, and figure 62 for ventral view with legs removed for clarity. Large T1-PL runs dorsad and lateral from T2-VC, extending into foreleg as T1-L; T1-AL and T1-PL join only via smaller tracheae extending from T1-Cx network. T1-L-Ty tympanum present at proximal end of tibia. T3-S with five branches: T3-DB, T3-lvl, T3-suf, T2-PL, T3-VB. T3-DB runs dorsad, with connection to T2-Wbr just dorsal of T3-S; T3-DB continues dorsally, with T3-AWL splitting dorsad and slightly lateral; T3-DB connecting in Y-shaped junction with T2-DLT from anteriad and T3-DLT posteriorly. T3-DB-Vi dorsal, extending posteriad, ending blind with several small tracheae posteriad. T3-AWL with sharp curve ventrad and laterally, with dorsal branch to T3-Wbr at apex of curve; T3-Wbr with small T3-W-c-r branch posteriad; T3-AL thin, joining with T3-PL ventral from A1-S and continuing as very thick T3-L. Additional T3-VL branching laterally from T3-VLT, extending into hind leg, and joining in multiple-tracheae junction with T3-L; extremely large T3-Fm extending dorsad into hind femur; smaller T3-Fm2 almost linear from T3-VL along ventral part of hind leg. T3-VC1 and T3-VC2 anterior and posterior, respectively, along T3-VLT. T3-lvl proceeds medially from T3-DB for a short distance before splitting into two branches, both joining with T3-VLT, one anteriad and one more posteriad. T3-suf running mediad, curving ventrally to connect with T2-VLT. T2-PL runs mediad before curving laterally, extending into midleg. T3-VB extends directly ventrad, connecting to T3-VLT near T3-suf connection.

ABDOMEN: A1..8-S present; A1..2-S modified, remaining A3..8-S all similar. A1-S with two additional connections: T3-PL, running ventrad with connection to thin T3-AWL before continuing into hind leg; and T3-PWL, connecting anteriorly from T2-S. A1..8-DB present, running directly dorsad from spiracle and leading to A n - DLT, arcing posteriorly to link with subsequent A n -DB. A1..4-DLT with paired A n -DLT-Vi, wide but flattened, extending medially; anterior A3,4- DB-Vi smaller. A5..8-DLT with single A n -DLT- Vi. A1..8-DC absent; however, a few A n -DLT-DVi with small lateral commissure to opposite side present. A1..8-VB present, running directly ventrad and mediad, following sternite wall and connecting with straight A n -VLT, spanning length of abdomen. A n -VC absent. Numerous visceral tracheae extending into gut, with many Vi spanning several segments and some connecting spiracles, including A3-Vi, linking with A6-Vi on specimen left side. Several visceral branches lie close to others, appearing to join but remaining separate, such as A3-Vi close to A8-Vi on right side. Several visceral tracheae are labeled in the plates and figures; readers are directed to the online 3D supplemental models for additional detail. Notably large A-Cr extending from A8-DB.

Figures

FIGURE 58. Gryllus sp (Orthoptera: Gryllidae), lateral view.

FIGURE 59. Gryllus sp (Orthoptera: Gryllidae), dorsal view.

FIGURE 60. Gryllus sp (Orthoptera: Gryllidae), ventral view.

FIGURE 61. Gryllus sp interior left side thorax cutaway. See inset for location of cut.

FIGURE 62. Gryllus sp thorax, ventral view. Leg tracheae have been removed for clarity.