Cardiocondyla compressa, Seifert, Bernhard, Okita, Ichiro & Heinze, Jürgen, 2017

Seifert, Bernhard, Okita, Ichiro & Heinze, Jürgen, 2017, A taxonomic revision of the Cardiocondyla nuda group (Hymenoptera: Formicidae), Zootaxa 4290 (2), pp. 324-356 : 351-353

Cardiocondyla compressa sp. nov. Seifert

Tab. 2, Figs. 17 – 19

Etymology. The species epithet refers to the extremely narrow petiole.

Type material. The holotype worker and one paratype worker without gaster are on the same pin labelled "TORRES STRAIT Hammond I. 10.33Sx142.12E", " 4 – 8 July 1974 H. Heatwole et E. Cameron" and "Holotype (top specimen) & Paratype Cardiocondyla compressa Seifert ". The types are deposited at SMNG.

Description of worker caste. Worker ( Tab. 2, Figs. 17 – 19 ): Small body size, CS 410 µm. Head elongated, CL/ CW 1.200. Postocular distance large, PoOc/CL 0.476. Eyes small, EYE 0.225. Frontal carinae immediately caudal of the FRS level parallel or slightly converging. Sculpture on head, mesosoma and waist much weaker than usually seen in the C. nuda group ( Figs. 17 – 19 ); foveolae on vertex less deeply impressed, of 14 – 19 µm diameter, and with an inner corona (a flat tubercle) of 7 – 9 µm diameter having the base of a decumbent pubescence hair in its center. Longitudinal sculpture on vertex almost absent, 1 – 2 weak longitudinal carinulae run parallel to frontal carinae in short distance to these. Weak semicircular rugae are found around the antennal fossae. Lateral mesosoma on whole surface regularly microreticulate-foveolate; longitudinal sculpture except for 4 – 6 weak and short carinulae on metapleuron completely absent; dorsal mesosoma rather shining ( Fig. 19 ) and with shallow reticulate-foveolateshagrinate microsculpture. Sides of petiole with a weakly sculptured microreticulum, dorsal petiole and postpetiole with shining, with only a delicate microreticulum. Cuticular surface of first gaster tergite rather smooth and shining but on its whole surface with a well-developed microreticulum. Pubescence hairs on gaster tergites moderately long, PLG/CS only 5.88%. Metanotal depression very shallow, MGr/CS 1.1%. Propodeal spines short but clearly longer than in the C. mauritanica species complex. Dorsal propodeum sloping down to base of spines under an angle of 20°. Petiole very narrow, PEW/CS 0.250; petiole node much longer than wide. Postpetiole in dorsal view with convex (not angulate) sides and rather low, PPH/CS 0.327; postpetiolar sternite not bulging, thus approaching the condition in the C. mauritanica complex. Head, mesosoma, waist and appendages yellowish, gaster significantly darker. For morphometric data of 2 workers see Tab. 2.

Geographic range. Australia. The only known site is Hammond Island (-10.55, 142.20] in the Torres Strait in North Queensland.

Diagnosis. The species is characterized by a very narrow petiole, small size and reduced sculpture. Comments. The arguments for describing C. compressa as species different from C. atalanta are presented in section 4.4.

Figures

FIGURE 17. Head of the holotype of Cardiocondyla compressa sp. nov. in dorsal aspect.

FIGURE 18. Holotype of Cardiocondyla compressa sp. nov. in lateral aspect.

FIGURE 19. Holotype of Cardiocondyla compressa sp. nov. in dorsal aspect.