“Flying” or digging? The trapdoor spider genus Neocteniza Pocock, 1895: Redescription of three species, new records from Brazil, notes on natural history and first record of ballooning for Idiopidae (Araneae, Mygalomorphae)

The Neotropical trapdoor spider genus Neocteniza Pocock, 1895 is distributed throughout Central and South America. The genus currently comprises 18 species and little is known about the biology of these spiders. We provide an amended diagnosis for the genus Neocteniza and the species: N. minima Goloboff, 1987, N. australis Goloboff, 1987 and N. toba Goloboff, 1987, and also redescribe them. We include new records of these species from Brazil and notes on natural history of N. toba, providing data on burrow structure, diet, development and the first record of ballooning behavior for Idiopidae. We propose a terminology for the genitalia and consider homology among genital structures and among possibly stridulatory structures. We also discuss relationships of Neocteniza with other Idiopidae, stressing the uniqueness of the genus and its differences from all other Idiopidae including other Genysinae.

Analysis and description of burrow structure in four species of freshwater crayfishes (Decapoda: Astacoidea: Cambaridae) using photogrammetry to recreate casts as 3D models

Freshwater crayfishes use burrows for predator avoidance, desiccation prevention, foraging, and brood care. Based on their burrow ecology, crayfishes can be categorized as tertiary, secondary, or primary burrowers, with primary burrowers being semi-terrestrial and highly dependent on burrows for survival; secondary and tertiary burrowers have decreased burrow dependence and complexity. There has been limited investigation into the specifics of burrow structure. We investigated the factors that influence the structure of crayfish burrows including habitat structure and crayfish through the use of burrow casting and photogrammetry to recreate casts as 3D models. Examined species include the primary burrowing Lacunicambarus aff. diogenesGirard, 1852 and Creaserinus fodiens (Cottle, 1863), and the tertiary burrowing Faxonius rusticus (Girard, 1852) and Faxonius propinquus (Girard, 1852). Crayfish burrows (N = 17) were filled with polyester resin and cured burrow casts were excavated, and photogrammetry was used to recreate casts as 3D models. Burrow depth, number and widths of openings, number and widths of chambers, and number of ancillary tunnels were recorded. Differences in burrow features were analyzed by field site/habitat and crayfish species using stepwise linear regression, MANOVAs, and multiple factor analysis (MFA). From stepwise linear regression, “species” was a better predictor than “habitat of burrow structure.” Burrows constructed by L. aff. diogenes were significantly larger and have more chambers than burrows constructed by the other species examined; burrows of C. fodiens were significantly deeper than those of tertiary burrowers. Each species also created a stereotyped burrow shape. The morphometric differences between burrows of primary and tertiary species illustrate the relevance of these informal classifications. Differences between primary and tertiary species may be related to the species social behavior and ecology.

Biological characteristics, feeding and structure of tunnels of the greater mole-rat (Spalax microphthalmus) in the area of the regional landscape park “Velikoburlutskyi Steppe”

New data on the greater mole-rat’s biology in the territory of the Regional landscape park «Velikoburlutskyi steppe” (Kharkiv region, Ukraine) concerning nutrition, burrow structure and social structure are presented. The greater mole-rat has only one litter consisting of 1–3 pups during the year. Contrary to the prevailing general opinion that mole-rats lead solitary way of life we have found cohabitation of a female, a male and their young of the current year at three of the seven areas of our study. Young mole-rats settle in a new place at the end of June – early July. They can be found above ground often at this time. In the greater mole-rat population from the Regional Park “Velikoburlutskyi steppe” males are characterized by the body length of 220–260 mm, by hind foot length of 27–30 mm, by the body weight of 219–520 g. For adult females the average body length is 200–250 mm, the hind foot length is about 26–30 mm, the body weight ranges from 284 to 409.6 g. Many greater mole-rat specimens on the forehead or occiput have an individual light spot (yellowish-white) or a white longitudinal strip by which we can identify individuals at repeated catching. Eating the underground parts of plants, the mole-rat makes very long tunnels conducting by them horizontally and closely to the surface and throwing along them the large piles of soil (up to 0.5 m in diameter). Soil emissions marking feeding tunnels had a base diameter of up to 50–60 cm. In the nest part of the hole the number of habitable chambers and chambers for stocks can be up to 10, and they are located at the depth of 3.5 m. Digging activity of the mole-rat grows in late March – early April and in the autumn at the end of September – early October. We have repeatedly noted the appearance of emissions in the winter during the thaw. Mole-rats harm the agriculture with their digging activity (damage cultivated areas, digging under the plants and so on); in addition, mole-rats sometimes directly eat potato tubers, onion and other root vegetables. The total weight of one mole-rat stock can reach 16 kg. In one of burrows excavated by us near the vegetable gardens of locals in Nesterivka village of Velikoburlukskyi district in Kharkiv region we found 8 kg of potatoes, 4 kg of carrots, 3 kg of greater burdock roots, 0.6 kg of couch grass roots.

The platypus nest: burrow structure and nesting behaviour in captivity

The platypus nesting burrow, where females lay eggs and rear their young, has not been well studied. We have little knowledge of its structure and the process of construction. This study aimed to investigate nesting behaviour of breeding females and to describe the structure and features of the burrow. We used infrared cameras to record behaviour of captive breeding female platypuses during the nest-building period, over nine years. After the young had become independent, we excavated 11 nesting burrows and mapped their structural features. Nesting behaviour was observed 7–15 days after mating and was an indicator of gravidity. Females invested an average of 8 h 18 min over 3.5 nights, gathering and transporting wet nesting material to their burrows. The nests were composed mostly of native mat-rush leaves. Nesting burrows varied in length from 3.2 to 10.4 m. They contained narrow tunnels, ‘pugs’ of backfilled earth, dead ends, multiple entrances and a chamber at the end that contained the nest. Appropriate nesting sites and nesting materials must be provided to female platypuses for captive breeding programs to succeed.