Tachycines asynamorous

“Greenhouse camel cricket”

Figures 65 (lateral), 66 (dorsal, ventral)

Plates 41 (lateral), 42 (dorsal, ventral)

A single camel cricket, Tachycines asynamorous, was scanned, but substantial fluid infilling of tracheae resulted in assessing homology of many branches difficult. Although of suboptimal quality, this specimen was included because of its placement within Orthoptera and the relative modifications of the mesothoracic tracheae, specifically how they relate to modifications for sound reception. Identifiable tracheae are labeled and described here but should be considered preliminary.

Our mesothorax assessments differ from Ander (1939), particularly with H-DCT and H-VCT. Ander identifies most of the larger tracheae extending into head as multiple branches of H-VCT and the small branch as H-DCT, whereas we have determined the small dorsal branch is T2-VB, the next ventral branch is H-DCT, followed by H-VCT, which does have a split into H-VCT and a smaller anterior trachea that has T1-AL ventrad.

DESCRIPTION: HEAD: T1-DLT partially visible and likely extending into head capsule. H-DCT and H-VCT both thick, with dorsal-ventral connection likely but not visible. Several air spaces visible, likely preservational artifacts. H-VCT splits into two branches, large dorsal one and smaller ventral, which proceeds anteriorly with T1-AL ventrad.

THORAX: T2-S with five branches: T2-DB, T2-VB, H-DCT, H-VCT, and T1-PL. T2-DB running dorsad and anteriad, extending into head capsule after broad curve along prothorax. H-DCT thick, extending anteriad through prothorax into head capsule. H-VCT splitting into two branches: large dorsal trachea, extending anteriad into head, and a smaller ventral branch, extending anteriad into head with T1-AL ventrad. T2-VC not visible but likely present; many ventral thoracic tracheae infilled with fluid. T2-DB runs dorsad, with T2-AL branching in hairpinlike turn ventrad into T2-L. Remaining branches of T2-DB not visible. T2-VB partial, with T-shaped intersection with T2-VLT. H-DCT and H-VCT both large, of similar size, extending into head as described above. T1-PL running directly ventrad, partial, likely joining with T1-AL but not visible in this scan. T3-S branches largely infilled and difficult to differentiate, appearing to include: T3-DB, T3-VB, T3-lvl, T2-PL, and T3-suf. T3-DB partial, with T3-AWL visible, leading to T3-AL, dorsad before curving sharply ventrad and posteriorly into hind leg. T3-VB running ventrad, joining with T3-VLT. T3-lvl extending mediad, joining with T3-VLT, with small branch posteriad connecting with T3-PL. T3-suf partial, extending mediad and slightly anteriorly. T3-VL possibly visible on specimen left side; T3-VL likely present but infilled.

ABDOMEN: A1..8-S present. A1-S modified from subsequent abdominal segments, with large ventral T3-PL branch. A n -VB visible on most segments, leading to partially infilled A n -VLT. A n -DB likely present but infilled and not visible. A n -DLT likewise probably present but not visible, likely infilled. Several visceral tracheae present from all A n -S.