OCHTERIDAE Kirkaldy, 1906

Polhemus, Dan A. & Polhemus, John T., 2012, Guide To The Aquatic Heteroptera Of Singapore And Peninsular Malaysia. Ix. Infraorder Nepomorpha, Families Ochteridae And Gelastocoridae, Raffles Bulletin of Zoology 60 (2), pp. 343-359 : 344

Family OCHTERIDAE Kirkaldy

Discussion. — The Ochteridae , or velvet shore bugs, comprise a small family containing three extant genera: the widespread Ochterus , which is pantropical and the only genus occurring in Singapore and Peninsular Malaysia; Megaochterus, endemic to Australia; and Ocyochterus , confined to the Neotropical region.As a whole, the Ochteridae exhibit two major geographic foci of species radiation, in South America ( Schell, 1943) and Melanesia ( Baehr, 1990a, 1990b; Kormilev, 1971, 1973) respectively. In the Eastern Hemisphere, species richness diminishes markedly west of Huxley’s Line ( Schell, 1943; Kormilev, 1971, 1973; Gapud & San Valentin, 1977; Gapud, 1981, 1995; Baehr, 1990a, 1990b; Nieser & Chen, 1992), although the fauna of Singapore and Malaysia is undersampled and contains new species, as described below.

Ochteridae are recognised among the nepomorphan families by their large eyes, presence of ocelli, slender four-segmented antennae, transversely rugose frons and clypeus, long labium with segment III much longer than the others, slender legs with the fore femora enlarged, a tarsal formula of 2-2-3, the forewing membrane with several closed cells but no anastamosing veins, and unique genitalia with the right paramere greatly enlarged in relation to the left and bearing distal appendices. Despite being superficially similar in external appearance to members of the Leptopodomorpha, and inhabiting similar littoral and hygropetric habitats, the Ochteridae possesses a suite of character states typical of Nepomorpha , including the short, ventrally inserted antennae and asymmetrical male genitalia, as well as a tubular spermatheca (Schuh & Slater, 1995). The primary characters currently used for species separation are the shape of the male right paramere ( Figs. 5–7 , 10, 11 , 13, 14 , 17, 18 , 23, 24 , 26, 27 ), the shape of the medial process on the male pygophore ( Figs. 8, 9 , 12 , 15 , 19 , 25 , 28 ), the striations on the frons and clypeus ( Figs. 29–34 ), and the dorsal colour pattern ( Figs. 1–4 , 21, 22 ).

Ochterids are usually beautifully marked with spots and flecks of blue, lavendar, green, orange, or yellow on a darker background, and such markings are often distinctive among species and useful in taxon separation. The markings consist of two distinct types: depigmented integument (as in the case of yellowish or whitish spots), and pruinose patches of bluish, purplish, or greenish structural colouration occurring on the surface of the integument. The former can become less conspicuous over time in specimens stored for many decades in alcohol, which fades dark colors, while the latter can be degraded or lost in specimens killed by use of ethyl acetate, or pinned through the body so that internal greases and oils spread across the body surface, thereby compromising the structural colors. The best preservation of colour patterns is therefore obtained by collecting specimens directly into 80% ethanol, and then drying them under a lamp in the lab and point-mounting them for long-term vouchering as dry pinned specimens. The photographs of dorsal colour patterns in this work are taken from specimens prepared using such methods.

The family name Ochteridae was first proposed by Kirkaldy (1906). Because Latreille (1809) had earlier proposed the unnecessary replacement name Pelogonus for Ochterus , this family is treated under the name Pelogonidae in many works published prior to Kirkaldy’s checklist.

Figures

Figs. 5–9. O. marginatus (Latreille), male, structural details. 5, Male right paramere, specimen from Vietnam, CL 4368.6, Superior appendage of right paramere, specimen from Vietnam, CL 4368. 7, Superior appendage of right paramere, specimen from Indonesia, Bali, CL 2170. 8, Medial process of pygophore, specimen from Vietnam, CL 4368. 9, Medial process of pygophore, specimen from Indonesia, Bali, CL 2170.

Figs. 10–12. O. signatus, new species, male, structural details, specimen from Malaysia, Perak, CL 2081. 10, Male right paramere. 11, Superior appendage of right paramere. 12, Medial process of pygophore.

Figs. 13–16. O. pseudomarginatus, new species, male, structural details, specimen from Malaysia, Perak, CL 2078. 13, Male right paramere. 14, Superior appendage of right paramere. 15, Medial process of pygophore. 16, Endosoma.

Figs. 17–20. O. singaporensis, new species, male, structural details, specimen from Singapore, Bukit Timah. 17, Male right paramere. 18, Superior appendage of right paramere. 19, Medial process of pygophore. 20, Endosoma.

Figs. 23–25. O. thienemanni Jaczewski, male, structural details, specimen from Indonesia, Bali, CL 2170. 23, Male right paramere. 24, Superior appendage of right paramere. 25, Medial process of pygophore.

Figs.26–28. O. noualhieri Baehr, male, structural details, specimen from Indonesia, Celebes, CL 2127. 26, Male right paramere. 27, Superior appendage of right paramere. 28, Medial process of pygophore.

Figs. 29–34. Ochterus species, colour photographs of head, anterior view, showing pattern of striations on frons.29, O. marginatus (Latreille), female, specimen from Vietnam, Cao Bang Prov., CL 4368. 30, O. thienemanni Jaczewski, female, specimen from Indonesia, Bali Prov., CL 2170. 31, O. signatus, new species, female, specimen from Vietnam, Lam Dong Prov., CL3085. 32, O. pseudomarginatus, new species, female, specimen from Malaysia, Perak, CL 2078. 33, O. noualhieri Baehr, female, specimen from Indonesia, Sulawesi Utara Prov., CL 2114. 34, O. singaporensis, new species, male, specimen from Singapore, Bukit Timah.

Figs. 1–4. Ochterus species, colour photographs of dorsum. 1, O. marginatus (Latreille), specimen from Thailand, Chonburi Prov. 2, O. signatus, new species, specimen from Malaysia, Perak, CL 2081. 3, O. pseudomarginatus, new species, specimen from Malaysia, Pahang, CL 2072. 4, O. singaporensis, new species, specimen from Singapore, Bukit Timah.

Figs. 21–22. Ochterus species, colour photographs of dorsum. 21, O. thienemanni Jaczewski, specimen from Indonesia, Bali, CL 2170. 22, O. noualhieri Baehr, specimen from Indonesia, Celebes, CL 2127.