New species, new combinations, and morphological notes of South American Ambrysinae (Heteroptera: Naucoridae).

Although recent studies have been published on Ambrysinae (Naucoridae) from the Neotropical region, few efforts have been made to improve the taxonomic knowledge of this subfamily in Brazil. Two genera of Ambrysinae containing the greatest number of species in South America were recently established to accommodate species previously classified as Ambrysus Stål: Australambrysus Reynoso & Sites and Maculambrysus Reynoso & Sites. The subgeneric classification of Ambrysus has also changed, including the elevation of Melloiella De Carlo back to full generic status.

A new species of Maculambrysus Reynoso & Sites, 2021 (Hemiptera: Heteroptera: Naucoridae) from an aguaje palm swamp in southeastern Peru.

The neotropical saucer bug genus Maculambrysus Reynoso & Sites is currently represented by five species from Tabasco, Mxico to Par, Brazil. Presented here is the description of a sixth species, Maculambrysus gallicei n.sp.

Revision of Limnocoris Stål (Heteroptera: Nepomorpha: Naucoridae) of the Guiana Shield and Amazon regions.

The species of Limnocoris of the Guiana Shield and Amazon regions of South America are revised, including the descriptions of five new species: L. amazonensis n. sp.

Revision of the Ambrysus signoreti Stål species complex (Heteroptera: Naucoridae: Ambrysinae). Section 2.

The Ambrysus signoreti Stål species complex was recently diagnosed and subdivided into three sections based on morphology of the female subgenital plate. In the present study, the species in the second section, characterized by the posterior margin of the subgenital plate with central lobe extending posteriorly further than the posterolateral corners, are revised. Supplemental descriptions for four species described by La Rivers and Usinger are provided.

The Australambrysus plax (La Rivers, 1967) species complex (Heteroptera: Naucoridae), with descriptions of three new species.

The taxonomy of the neotropical saucer bug genus Australambrysus Reynoso & Sites, 2021 is poorly understood. Although 24 species have been described, the genus is in need of revision and many new species await description. A clade of species of Australambrysus exhibits a similar appression of the propleura to the prosternum as do species of the North American Ambrysus Stål, 1862 subgenus Syncollus La Rivers, 1965.

Notes on the morphology of two species of Limnocoris Stål (Heteroptera: Naucoridae) from South America.

In the present study, new distribution records and notes on the wing polymorphism of Limnocoris pallescens (Stål, 1861), a species distributed in Colombia and Venezuela, are presented. Also, after the discovery of two female paralectotypes of L. pectoralis Montandon, 1897 deposited at the Natural History Museum in London, ongoing uncertainty about the shape of the diagnostic mediosternite VII (subgenital plate) of this species has been resolved.

Revision of the Ambrysus signoreti Stål species complex (Heteroptera: Naucoridae: Ambrysinae). Section 1.

The species-rich Ambrysus signoreti Stål species complex is diagnosed and subdivided into three sections based on morphology of the female subgenital plate. The species in the first section, characterized by the posterior margin of the subgenital plate with posterolateral corners extending posteriorly further than the central lobe, are revised. The group includes four species: two previously described from Mexico (Ambrysus cosmius La Rivers, A.

Nomenclatural updates to the taxonomy of Naucoridae (Hemiptera: Heteroptera).

N/A.

The Naucoridae (Heteroptera: Nepomorpha) of Madagascar, with revisions of Temnocoris and Tsingala (Laccocorinae).

The island nation of Madagascar was surveyed extensively through a series of expeditions to determine the fauna of Naucoridae. Previously, 17 species in four genera had been reported from the country. All taxa previously recorded from Madagascar were re-collected, with the exception of three species, Macrocoris flavicollis Signoret, Temnocoris starmuhlneri Poisson, and Tsingala nossibeanus (Bergroth).

The Gyrinidae (Coleoptera) fauna of Thailand: Key to tribes and genera, with new records and keys to species of Dineutini and Gyrinini.

Eighteen species and four genera of the family Gyrinidae are recorded from Thailand. Seven species, belonging to three genera in the tribes Dineutini and Gyrinini, are here treated in detail. Dineutus sitesi Gustafson, Hjek Miller, D.

Review of the Patrus landaisi species group from Thailand with description of three new species (Coleoptera, Gyrinidae).

A survey of the whirligig beetles of the genus Patrus Aubé, 1838 occurring in Thailand belonging to the newly designated Patrus landaisi species group is presented. Three new species are described and illustrated: P. garuda sp.

Revision of Limnocoris Stål (Heteroptera: Nepomorpha: Naucoridae) of the tropical Andes.

The species of Limnocoris of the tropical Andes of South America are revised, including the descriptions of eight new species: L. chrysosetosus n. sp.

A review of emCryphocricos/em Signoret, 1850 (Naucoridae: Cryphocricinae) with descriptions of three new species.

The genus Cryphocricos Signoret, 1850 was recently determined in a molecular phylogeny to be distantly related to other taxa of the subfamily Cryphocricinae to the extent that it is now once again the sole member of the subfamily. This exclusively New World group of aquatic bugs lives in fast and usually turbulent current and respires by means of a plastron. Efforts to identify morphological features to distinguish among the species have largely fallen short, and some species have been established based on features that exhibit a high degree of intraspecific variation overlapping those of other species.

The Pleidae (Hemiptera, Heteroptera) of Thailand, with the descriptions of two new species and a discussion of species from Southeast Asia.

The family Pleidae is represented in Thailand by four species in the genus . Two of these species, and , are widespread and relatively common in Southeast Asia. Two other species, Cook, and Cook, , are described and only known from Thailand.

The larvae of Phaenandrogomphus Lieftinck, 1964 in Thailand, including the description of P. tonkinicus (Fraser, 1926) with a larval diagnosis and new province records of P. asthenes Lieftinck, 1964 (Odonata: Gomphidae).

The larva of Phaenandrogomphus tonkinicus (Fraser, 1926) is described for the first time based on several F-0 larvae collected in Chiang Mai and Nan provinces of Thailand. The larva of P. tonkinicus differs from that of P.

Revision of the American genus Steinovelia Polhemus amp; Polhemus, 1993 (Heteroptera: Gerromorpha: Veliidae).

The genus Steinovelia Polhemus Polhemus, 1993 is distributed from southeastern Canada to northeastern Argentina and has been considered to contain five valid species: S. permista (Drake, 1951a), S. placida (Drake, 1951a), S.

The probable larva of Anotogaster gregoryi Fraser, 1923, with new distributional records of the genus from northern Thailand (Odonata: Cordulegastridae).

The probable larva of Anotogaster gregoryi Fraser, 1923 is described for the first time by supposition based upon four F-0 larvae collected in the provinces of Loei and Phitsanulok, which are new province records for Anotogaster in Thailand.

Descriptions of four new species of the Ambrysus signoreti Stål species complex (Heteroptera: Nepomorpha: Naucoridae.

The genus Ambrysus Stål is the most species rich genus of Naucoridae. Multiple species groups in the genus have been proposed, including the North American Ambrysus signoreti Stål complex. Four new species belonging to the A.

Revision of Limnocoris (Heteroptera: Nepomorpha: Naucoridae) of North America.

The North American species of Limnocoris are revised and total 13 species after the present study. Four new species are described and illustrated: L. chaetocarinatus n.

The larva of Amphigomphus somnuki Hämäläinen, 1996 and the first records of the genus Stylogomphus Fraser, 1922 for Thailand (Odonata: Gomphidae).

The larva of Amphigomphus somnuki Hämäläinen, 1996 is described for the first time based on an emerged male specimen from Chiang Mai Province, and several F-0 larvae collected in other provinces of Thailand. The larva of A. somnuki is the smallest and differs from A.

Revision of the Ambrysus pulchellus Montandon species complex (Heteroptera: Nepomorpha: Naucoridae).

The Ambrysus pulchellus Montandon species complex is revised and includes A. buenoi Usinger, A. californicus Montandon, A.

Revision of the Ambrysus pudicus Stål species complex (Heteroptera: Nepomorpha: Naucoridae) with the description of a new species from southern Mexico.

The Ambrysus pudicus Stål species complex is revised, its species diagnosed, and an illustrated key is presented. The complex includes A. abortus La Rivers, A.

Revision of the Ambrysus hybridus Montandon species complex (Heteroptera: Naucoridae: Cryphocricinae) with the description of a new species from Mexico.

The Ambrysus hybridus Montandon species complex is revised and includes A. convexus Usinger, A. fuscus Usinger stat.

Revision of the Ambrysus guttatipennis Stål species complex (Heteroptera: Naucoridae: Cryphocricinae) with the descriptions of six new species from Mexico.

The Ambrysus guttatipennis Stål species complex is revised and includes A. arizonus La Rivers, A. bispinus La Rivers, A.

Revision of the Neotropical genus Carvalhoiella De Carlo (Heteroptera: Nepomorpha: Naucoridae).

The genus Carvalhoiella De Carlo, 1963 includes saucer bugs (Heteroptera: Naucoridae) that live predominantly on the vertical rocks next to falls and cascades of waterfalls. Thus far, it has been recorded only in South America and includes three described species. In the present paper, based on type specimens and additional material, we present detailed distributions and diagnostic information of the three described species of Carvalhoiella and the descriptions of two new species from central-western Brazil: C.