Gender Identification and Classification of Drosophila melanogaster Flies Using Machine Learning Techniques

Drosophila melanogaster is an important genetic model organism used extensively in medical and biological studies. About 61% of known human genes have a recognizable match with the genetic code of Drosophila flies, and 50% of fly protein sequences have mammalian analogues. Recently, several investigations have been conducted in Drosophila to study the functions of specific genes exist in the central nervous system, heart, liver, and kidney. The outcomes of the research in Drosophila are also used as a unique tool to study human-related diseases. This article presents a novel automated system to classify the gender of Drosophila flies obtained through microscopic images (ventral view). The proposed system takes an image as input and converts it into grayscale illustration to extract the texture features from the image. Then, machine learning (ML) classifiers such as support vector machines (SVM), Naive Bayes (NB), and K -nearest neighbour (KNN) are used to classify the Drosophila as male or female. The proposed model is evaluated using the real microscopic image dataset, and the results show that the accuracy of the KNN is 90%, which is higher than the accuracy of the SVM classifier.

Three new species of Oxyethira Eaton, 1873 (Trichoptera: Hydroptilidae) from New Caledonia

Oxyethira Eaton, 1873 is one of the most diverse genera of Hydroptilidae, comprising over 240 species distributed in all biogeographical regions. Here three new species of Oxyethira (Trichoglene) Neboiss, 1977 are described and illustrated from male specimens collected in New Caledonia: O. (Trichoglene) hamus sp. nov., recognized by the hook-shaped apex of the long inferior appendages in lateral view and by the posterior margin of segment IX with a trilobed appearance in ventral view; O. (Trichoglene) rectangulata sp. nov., recognized by the rectangular shape of the inferior appendages, which are totally fused and with two pairs of small setae on the inner face; and O. (Trichoglene) spiralis sp. nov., recognized by the strongly curvilinear shape of the subgenital process in dorsal and lateral views and by the long process spiralling around the ejaculatory duct at the phallus apex.

A new species of Epeorus (Caucasiron) (Ephemeroptera, Heptageniidae) from Azerbaijan and Iran

A new species, Epeorus (Caucasiron) hyrcanicussp. nov., is described based on larval morphology and molecular data (COI) containing sequences from all Caucasian Caucasiron species described to date. The species is distributed in the Hyrcanian forest of southeastern Azerbaijan and northwestern Iran. Based on our wide-range sampling, the new species is likely endemic to this area. The most pronounced larval morphological diagnostic characters are the coloration pattern of abdominal sterna (a pair of oblique stripes and stripe-like medio-lateral maculae) and terga (triangular medial maculae), poorly developed projection of the costal margin of gill plates III, presence of hair-like setae on the surface of abdominal terga, and relatively wide shape of gill plates VII (in natural position from ventral view). The diagnostic characters are compared to related species, and primary information to habitat is provided.

Description of fifteen new species of the Hypoxys balteatus species group (Hemiptera: Heteroptera: Pentatomidae)

Hypoxys Amyot & Serville, 1843 (Hemiptera: Heteroptera: Pentatomidae: Edessinae), for a long time considered a synonym or subgenus of Edessa Fabricius, 1803, was recently revised and reinstated to the generic rank. This genus comprises 17 described species divided in four species groups: H. quadridens, H. oxyacanthus, H. triangularis, and H. balteatus species group. Also, there is a large number of new species yet to be described. The H. balteatus species group is diagnosed by: pronotum with posterior stripe smoky brown to black with black punctures within, sometimes these punctures are surrounded by small dark spots; punctures of the pronotal disc smaller and paler than those of the posterior stripe; anterolateral margin of pronotum yellow; anterior half of scutellum with punctures large, sparse, and also on dark spots; connexivum uniformly green, without dark spots; thorax ventrally with two pairs of brown to black rounded spots; apex of pseudosutures with black to brown round spots. This species group included so far only H. balteatus (Walker, 1868). Here we describe and assign 15 new species to this group: H. amyoti sp. nov. (Suriname: Powakka; French Guiana), H. aspilogaster sp. nov. (Brazil: Minas Gerais, Espírito Santo and Rio de Janeiro), H. belenensis sp. nov. (Brazil: Pará), H. bergrothi sp. nov. (Venezuela: Amazonas; French Guiana: Saint-Elie), H. breddini sp. nov. (Bolivia: Santa Cruz and San Carlos), H. caquetensis sp. nov. (Colombia: Caquetá), H. favachae sp. nov. (Suriname: Sipaliwini; Brazil: Amapá and Pará), H. gaucho sp. nov. (Brazil: Rio Grande do Sul), H. hyalinofasciatus sp. nov. (Ecuador: Sucumbíos), H. immaculatus sp. nov. (Bolivia: Beni), H. nigroantennatus sp. nov. (French Guiana: Roura), H. santarensis sp. nov. (Brazil: Pará), H. servillei sp. nov. (Brazil: Mato Grosso and Goiás), H. stysi sp. nov. (Suriname: Coronie, Sipaliwini; French Guiana: Cayenne), and H. venustus sp. nov. (Bolivia: Cochabamba). Descriptions, measurements, photos of dorsal and ventral view of each species, and of external genitalia of both sexes, an identification key, and distributional maps are presented.

Cryptaphelenchus abietis n. sp. (Tylenchomorpha: Aphelenchoididae) isolated from Cryphalus piceae (Ratzeburg) (Coleoptera: Scolytinae) emerged from Abies veitchii Lindl. (Pinaceae) from Nagano, Japan

Summary An undescribed Cryptaphelenchus species was isolated from a bark beetle, Cryphalus piceae that had emerged from a dead log of the Veitch’s fir, Abies veitchii, collected from Sugadaira Montane Research Center, University of Tsukuba, Nagano, Japan. The new species is characterised by its female post-vulval uterine sac (PUS) of less than one vulval body diam. in length and female posterior body end (tail) conical with elongate posterior part and variably shaped tip, seven male genital papillae, which are composed/arranged as a precloacal P1, P2 pair slightly anterior to cloacal opening, and two small pairs of glandpapillae near tail tip and very narrow bursal flap-like cuticular extension surrounding the male tail. In addition to these characters, the male apophysis appears wing-like in ventral view. In possessing an elongate posterior part, Cryptaphelenchus abietis n. sp. shares the female tail shape with C. borlossi, C. leptocaudus and C. sutoricus, and shares a short PUS with C. iranicus, C. varicaudatus, C. baujardi and C. paravaricaudatus. However, the new species can be distinguished from these species by other typological and morphometric characters and its molecular phylogenetic status. Phylogenetically, the new species is closest to Bursaphelenchus minutus, but can be clearly distinguished by morphological and molecular sequence characters.

Description of Heteracris lecoqi Yetchom-Fondjo & Kekeunou sp. nov. and Heteracris hannai Wandji & Kekeunou sp. nov. and redescription of Heteracris guineensis (Krauss, 1890) (Orthoptera: Acrididae) with comments on its ecology in the Southern part of Cameroon

The specimens studied were collected with sweep net and pitfall in the forests, agro-forests, herbaceous fallows, and crop fields of 14 localities in the southern part of Cameroon, from August 2015 to February 2018. The results show that Heteracris hannai sp. nov. and Heteracris lecoqi sp. nov. differ from previously known species of the same genus by the pattern of coloration and the details or shape of the phallic complex. H. lecoqi sp. nov. is characterized by light brownish body; male cercus with flattened, downcurved and obtuse apex; lophus strongly curved; interlophal space with V shape; apodeme of cingulum bow, convergent, with V-shape; valve of cingulum in lateral view longer than apical valve of penis; ramus in ventral view joined. H. hannai sp. nov. is distinct to other species by brown to grey body; male cercus with apex rounded, curved inside; lophus curved; interlophal space with U-shape; apodeme of cingulum thick, slightly parallel, with U shape; valve of cingulum in lateral view hardly longer than apical valve of penis; ramus in ventral view opened. The characteristics of H. guineensis are closer to H. hannai sp. nov. than to H. lecoqi sp. nov. H. lecoqi sp. nov. was collected only in the fallows while H. hannai sp. nov. was collected in the forests, agro-forests, fallows, and crop fields. Compared to H. guineensis, both new species are scarce in the natural vegetation and their distribution area is limited to two and four localities respectively for H. lecoqi sp. nov. and H. hannai sp. nov. All these three grasshopper’s species were recorded as accidental species in all types of vegetation.

Two new species of Flintiella Angrisano 1995 (Trichoptera: Hydroptilidae: Stactobiini) from northern Brazil

Two new species of Flintiella Angrisano 1995 are described and illustrated from specimens collected with light traps in the states of Pará and Roraima, northern Brazil. Flintiella serrana sp. nov. can be distinguished from all other species in the genus by the subgenital plate with incised apex, and two pairs of ventral processes. Flintiella triaena sp. nov. is distinctive with no clearly similar congeners and can be distinguished from all known species in the genus by the trident-like subgenital plate in ventral view. Additionally, we record the genus Flintiella for the first time in Roraima State.

A new species of the large-headed coastal marine turtle Solnhofia (Testudinata, Thalassochelydia) from the Late Jurassic of NW Switzerland

Background The large-headed turtle Solnhofia parsonsi is known by a handful of specimens from the Late Jurassic of Germany and Switzerland (maybe also France). Solnhofia parsonsi is traditionally regarded as a “eurysternid” Thalassochelydia, a group of small to medium sized, mostly lagoonal or marginal turtles found almost exclusively in the Late Jurassic of Europe. More recently, Solnhofia parsonsi has been proposed to be a close relative of Sandownidae, an enigmatic group of Cretaceous to Paleogene turtles characterized by a derived cranial anatomy and a wider geographical distribution. Sandownids may therefore have evolved from thalassochelydian ancestors such as Solnhofia parsonsi. Methods We herein describe new material of Solnhofia from the Kimmeridgian (Late Jurassic) of Porrentruy, NW Switzerland. The bulk of the material consists of an association of a cranium and over 180 shell bones found together in a block of marly limestone. A second cranium and a mandible from slightly younger, but nearby localities are also described. Results We refer the new material to Solnhofia brachyrhyncha n. sp. The new species shares with Solnhofia parsonsi a relatively large head, an extensive secondary palate formed primarily by the maxillae, a greatly developed processus trochlearis oticum with a contribution from the parietal and quadratojugal, a large jugal-palatine contact in the floor of the fossa orbitalis, and a posteromedial process of the jugal running on the dorsal surface of the maxilla and pterygoid. Some of these characteristics are also present in sandownids, but our morphological study clearly shows that Solnhofia brachyrhyncha is closer to Solnhofia parsonsi than to any sandownids. Discussion Solnhofia brachyrhyncha differs from Solnhofia parsonsi in many aspects, notably: a shortened and broader cranium, a shorter and posteriorly broader upper triturating surface with a slightly sinusoidal lateral margin and without contribution from the palatine, a processus trochlearis oticum more oblique in dorsal or ventral view and less concave in anterior view, choanae that do not extend posteriorly on the pterygoids, a more developed processus pterygoideus externus, a condylus mandibularis situated anterior to the level of the occipital plane, a greater ventral exposure of the parabasisphenoid, a mandible about as wide as long, a relatively short symphysis, a lower triturating surface widened posterolaterally thanks to the presence of large laterally projecting dentary tubercles, a stouter and shorter coronoid process, a splenial positioned more anteriorly along the mandibular ramus, costo-peripheral fontanelles extending more anteriorly and posteriorly along the costal series, and an escutcheon shaped central plastral fontanelle formed mostly by the hypoplastra. In addition to the morphology of the new species, we also briefly discuss about observable ontogenetic variations and possible taphonomic origin of the assemblage.

New species of caddisflies (Trichoptera: Psychomyiidae, Hydropsychidae, Leptoceridae) from Mekong tributaries, Cambodia

Males of four new species of caddisflies from Kampong Speu and Siem Reap provinces, Cambodia [Psychomyia kimcheangi n. sp. (Psychomyiidae), Macrostemum siemreapensis n. sp. (Hydropsychidae), Leptocerus angkorwatensis n. sp. (Leptoceridae), and Trichosetodes kampongspeuensis n. sp. (Leptoceridae)] are described and illustrated. Psychomyia kimcheangi n. sp. can be distinguished from other species by characters of the inferior appendages. The main body of each inferior appendage has two branches that are separated near its base but are parallel and close together until the end. In Macrostemum siemreapensis n. sp. the dorsal tip of the phallus has no curved hooklet but instead a knot-like protruding structure in ventral view and looped-like structure in dorsal view. Leptocerus angkorwatensis n. sp. can be distinguished from others by the characters of long needled-like preanal appendages. Trichosetodes kampongspeuensis is distinguished from others by the characters of segment IX in ventral view, which is asymmetrical, and inferior appendages that are not divided and asymmetrical.