Gomphomacromia signata, Tennessen, 2024

Tennessen, Kenneth J., 2024, Gomphomacromia signata sp. n. from the Andes Mountains in Ecuador (Odonata: Synthemistidae), International Journal of Odonatology 27, pp. 19-25 : 20-24

publication ID	https://doi.org/10.48156/1388.2024.1917256
persistent identifier	https://treatment.plazi.org/id/03A2E731-F016-FF88-FCBF-79EAFC359F88
treatment provided by	Felipe
scientific name	Gomphomacromia signata
status	sp. nov.

Treatment

Gomphomacromia signata sp. n. Tennessen

( Figures 1–6 View Figure 1 View Figure 2 View Figure 3 View Figure 4–6 , 9 View Figure 9 , 10 View Figure 10 )

Etymology

Name formed from the Latin ‘ signum’ (adj., bearing marks, signs, or flags), referring collectively to the yellow spots on the frons, the isolated oval yellow spot on the anterolateral part of the mesepimeron and the forked metepisternal and metepimeral yellow stripes, a unique combination within the genus.

Holotype ♂ Ecuador, Napo Province, hillside seep along Hwy. E20, about 5.5 km E of Papallacta in a straight line (0.37436 S, 78.07705 W, 2716 m a.s.l.), 5 November 2013, K. J. Tennessen leg. Deposited in Florida State Collection of Arthropods. GoogleMaps

Description of holotype male

A dark brown medium-sized dragonfly with yellow markings on the postfrons, thorax and abdomen ( Fig. 1 View Figure 1 ).

Head. Eyes in life green dorsally, brown anteriorly and laterally, pale gray ventrally ( Fig. 2 View Figure 2 ); labrum orange-tan, clypeus and antefrons dark brown, postfrons mostly yellow with brown medially, vertex brown; labium mostly tan, darker distally; mandibles and maxillae orange-tan; rear of head orange-brown.

Thorax. Total surface closely beset with long dark setae. Prothorax brown, middle lobe light brown. Pterothorax: middorsal carina narrowly yellow, mesepisternum dark brown but with a small, narrow anterior and posterior yellow spot ( Fig. 2 View Figure 2 ); mesepimeron dark brown with a large oval yellow spot on anteroventral (lower) portion; metepisternum brown with a wide yellow stripe, narrow ventrally, widening dorsally and forked at upper end, the dorsal prong short, blunt and extending upward onto mesepisternum; metepimeron brown with a yellow rectangular stripe with an upper extension ( Fig. 1 View Figure 1 ); mesinfraepisternum and metinfraepimeron brown; venter of pterothorax gray-brown. Legs varying shades of medium to dark brown, coxae partly yellow, femora yellow at bases, darker apically; keel on prothoracic tibia extending along distal 0.57 of tibia; metathoracic femur 4.7 mm long, metathoracic tibia 5.1 mm long.

Wings. Hyaline, venation brown; dark brown spot in basal cells between costa,subcosta and RA;yellow wash in subcostal space ( Fig. 1 View Figure 1 ); triangles free; hw anal loop 5-celled; fw Ax 9, hw Ax 6; fw Px 8, hw Px 9; pterostigma orange-brown, surmounting 1.6 to 1.9 cells.

Abdomen. Color pattern dark brown, paler laterally, dorsum with yellow spots: S1 with a posteromedial yellow spot; S2 with a pair of anterolateral yellow spots and another pair of submedial yellow spots just past midlength; S3–7 with a pair of submedial yellow spots divided by dark transverse carina, anterior part of yellow spot larger than posterior part, the spots largest on S3 & S4, diminished in size on S5 & S6, very small on S7; S8 with pair of large, round submedial yellow spots; S9 & 10 dark brown ( Fig. 1 View Figure 1 ); posteroventral corner of S1 tergum broadly curved, lacking denticulate process; auricles brown, prominent, 6–8 black denticles on posterior margin; S10 deeper than S 9 in lateral view ( Fig. 5 View Figure 4–6 ). Anterior hamule laminate with a square notch; posterior hamule in ventral view slightly curved, a very short, blunt process at midlength directed medially and a longer, darker, rounded, denticulate distal lobe 0.45 mm long ( Figs 3 View Figure 3 , 9 View Figure 9 ). Anal appendages dark brown, with many dark setae; cercus in dorsal view nearly straight, apical fourth angled inward so that the pair converges distally, tips narrowed ( Fig. 4 View Figure 4–6 ), in lateral view slightly arched, ventrolateral margin with a minute sharplytipped denticle at 3/10 length ( Fig. 5 View Figure 4–6 ); epiproct about 0.7 times length of cerci, in dorsal view of the appendages with tips visible beyond lateral margins of cerci ( Fig. 4 View Figure 4–6 ) in normal repose, in ventral view as wide distally as basally, with lateral margins slightly incurved, distal margin sinuous, tips protruding posterolaterally ( Fig. 6 View Figure 4–6 ), in lateral view tips recurved, tooth-like ( Fig. 5 View Figure 4–6 ).

Measurements (mm). Total L 39.4, head W 5.3, hind wing L 26.3, abdomen L (excluding cercus) 26.9, cercus L 1.7, pt L 1.67–1.8.

Female

A female of the new species was photographed by Cary Kerst at the same location and on the same day that I collected the male ( Fig. 7 View Figure 7 ); it was not collected. The image shows that the color pattern is similar to that of the male holotype, although the eyes have only slight greenish reflections dorsally, the yellow spots on S2–7

are larger and S8 is totally brown. The yellow spots on the postfrons and large yellow spot on the lower mesepimeron are evident in the photograph (females of G. fallax have a completely dark postfrons and mesepimeron, and the paired yellow spots on the abdomen are smaller than in G. signata ). The tip of the abdomen of G. signata as shown in dorsolateral view in the photograph ( Fig. 7 View Figure 7 ), does not allow a definitive view of the vulvar lamina. However, the lobes of the vulvar lamina appear to be short, possibly much shorter than in G. fallax (see Fig. 2i View Figure 2 in von Ellenrieder & Garrison, 2005).

Diagnosis

Gomphomacromia fallax is a darker species than G. signata, lacking yellow on the postfrons and having less yellow on the thorax and abdomen. In particular, the thoracic pattern of G. fallax differs in lacking an oval yellow spot on the lower part of the mesepimeron and the metepisternal and metepimeral stripes are unforked. The abdominal pattern of G. fallax is similar to that of G. signata , although the submedial yellow spots are much smaller ( Fig. 8 View Figure 8 ).

In G. signata , small dark brown spots are present in the base of all four wings and there is a yellow wash in the rows of cells between the costa and vein RA ( Fig. 1 View Figure 1 ); the wings bases and anterior rows of cells in males of G. fallax are clear ( Fig. 8 View Figure 8 ).

The distal lobe of the posterior hamule is longer in G. signata (0.45 mm) compared to G. fallax (0.25– 0.32 mm, n = 9 from Ecuador and Bolivia) ( Fig. 9 View Figure 9 ). The anterior hamule of the G. signata holotype has a square notch whereas the notch in G. fallax is usually much less conspicuous ( Fig. 10 View Figure 10 ), but at least one specimen of G. fallax from Ecuador had a square notch. The epiproct is rectangular in G. signata compared to elongate and tapered in G. fallax (see von Ellenrieder & Garrison, 2005). Epiproct shape in G. signata resembles that of G. nodisticta .

The length of the keel on the prothoracic tibia exceeds half the length of the tibia in G. signata (0.57) and G. fallax (0.50–0.66); the keel is shorter (0.33–0.50 length of tibia) in the southern species, G. chilensis , G. nodisticta and G. paradoxa (von Ellenrieder & Garrison, 2005).