Prohydrometra teatara D. Polhemus, 2022

Polhemus, Dan A., 2022, Two new genera and six new species of Terrestrial Hydrometridae (Hemiptera: Heteroptera) from French Polynesia, Zootaxa 5190 (1), pp. 69-98 : 87

Prohydrometra teatara D. Polhemus n. sp.

Figs. 22 , 26 , 29

Apterous male. Length 5.85, width 0.50.

Color. Ground color brown; abdominal mediotergites light-brown, matte. Head broadly tinged with blackish on both anteocular and postocular parts. Thorax medially light colored dorsally, metanotum with median light area spreading along anterior margin of abdomen; each laterotergite with light area anteriorly. Venter of thorax and abdomen dark. Legs light-brown, antennae light-brown to brown; coxae and trochanters mostly light-brown.

Structure. Head relatively long (2.30), widest at antennal tubercles (0.35); set with bristly setae beneath; gular lobe large, rounded; labium reaching well caudad of eyes, onto prosternum; head with anteocular portion slightly longer than postocular portion, ratio of anteocular/postocular portions: 1.35/0.90; interocular space/width of an eye: 0.10/0.08; anteclypeus small, broadly rounded anteriorly. Antennae with lengths of antennomeres I:II:III:IV = 0.28: 0.35: 2.08: 1.30. Pronotum length 0.73; remainder of thorax 0.48 (to lateral suture behind metacetabula); abdomen length 2.40. Wing pads, if present, very small, not visible, hidden under pronotum. Thoracic and abdominal sterna with short bristly setae, about equally dense on all segments. Distance between anterior and middle coxae (measured between closest margins) 0.20; between middle and hind coxae 0.28. Acetabula without pits. Venter without black denticles.

Proportions of legs as follows: Femur, tibia, tarsomere I, tarsomere II, tarsomere III of fore-leg, 2.10: 2.48: 0.05: 0.35: 0.22; of middle-leg, 2.30: 2.67: 0.05: 0.40: 0.20; of hind-leg, 2.70: 4.20: 0.05: 0.50: 0.22.

First abdominal segment short, transverse, clearly delineated by a suture posteriorly. Mediotergites longer than wide. Male abdominal sternum VII with two patches of erect bristles, set close together, but separated from the anterior margin ( Fig. 22 ); segment VIII cylindrical, unmodified, without distal process.

Micropterous female. Length 6.80, width across abdomen 0.75. Similar in most respects to male, but abdomen broader, deeper; tergum VIII distally truncate, without distal process; margins of laterotergites without setae. Abdominal terminalia simple, without modification.

Brachypterous and macropterous forms. Unknown.

Type material examined (all micropterous). Holotype, male: FRENCH POLYNESIA, Society Islands , Tahiti , Tahiti Iti, Mts Teatara, 1085 m, 17°47'48"S, 149°14'18"W, 7 September 2006, Lot 01, pyrethrin fog of horizontal mossy log, J. K. Liebherr ( CUIC) . Paratype: FRENCH POLYNESIA, Society Islands , Tahiti : 1 female, Tahiti Iti, Mts Teatara, 1080–1100 m, 17°47'47"S, 149°14'20"W, 17 September 2006, Lot 07, pyrethrin fog on mossy Weimannia trunk, J. K. Liebherr ( CUIC) .

Distribution. French Polynesia, Society Islands, endemic to Tahiti, on Tahiti Iti ( Fig. 29 ).

Etymology. The species name “ teatara ” is a noun in apposition, and refers to the Teatara massif type-locality, on the island of Tahiti.

Discussion. Prohydrometra teatara is the smaller of the two Prohydrometra species known from Tahiti, with a male body length less than 6.0 mm, and a female body length of less than 7.0 mm. It may be easily distinguished from P. gagnei , the other Tahitian species, by the structure of male abdominal ventrite VII, which bears two small patches of black bristles ( Fig. 22 ), rather than the large, hooked, sclerotized processes seen in P. gagnei ( Figs. 19, 20 ). The other two Prohydrometra species that bear patches of bristles on male abdominal ventrite VII either have these patches far more elongate, as in P. tohiea from Moorea ( Fig. 23 ), or far more widely separated, as in P. johnpolhemi from Raiatea ( Fig. 24 ).

Ecological notes. The two known specimens of P. teatara were obtained by light pyrethrin fogging of mossy logs or Weinmannia L. tree trunks, indicating that it has a terrestrial ecology similar to other Prohydrometra species.

Figures

FIGURE 29. Distribution of Prohydrometra n. gen. species in the eastern Society Islands. Triangle = P. tohiea n. sp.; circle = P. moorea n. sp.; squares = P. gangei; pentagon = P. teatara n. sp.

FIGURES 19–24. Prohydrometra n. gen. species, male ventral terminal abdomen. 19. P. gagnei, specimen from Tahiti, Mt. Marau. 20. P. gagnei, specimen from Tahiti, Mt. Mauru, showing yellowish-brown coloration. 21. P. moorea n. sp., specimen from Moorea, Mt. Tohiea. 22. P. teatara n. sp., specimen from Tahiti, Mts. Teatara. 23. P. tohiea n. sp., holotype, specimen from Moorea, Mt. Tohiea. 24. P. johnpolhemi n. sp., specimen from Raiatea, Trois Cascade.

FIGURES 25, 26. Photographs of habitat for Prohydrometra n. gen. species on Moorea and Tahiti. 25. Mt. Tohiea summit area, CL 7500, habitat for P. moorea n. sp. and P. tohiea n. sp.. 26. Tahiti Iti, Mts Teatara, 1080 m. mossy Weimannia trees providing habitat for P. teatara n. sp..