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Saturday 29 June 2024

Caprimulgus ritae: A new species of Nightjar from Timor and Wetar.

The Wallacean bioregion lies between the Asian and Australian continents, and has been recognised as significant for our understanding of evolution and biogeography since the nineteenth century. The islands of Wallacea are separated from the Asian and Australian landmasses by areas of deep water, and have never been connected to either area by a land-bridge, which means that every Animal and Plant there is descended from individuals that managed to cross by sea or air, leading to a huge number of endemic species (species not found anywhere else). Despite this significance, many groups of organisms are relatively understudied in Wallacea, and new species are still discovered there on a regular basis.

Nightjars are nocturnal Birds with highly cryptic plumage, seldom observed by Humans despite a near-global distribution. Their highly unobtrusive nature, combined with the similar appearance of different species of Nightjar makes them extremely hard to study, although in recent years, some progress has been made on differentiating Nightjar species by their songs, aided by the fact that Nightjars will respond to the recorded calls of members of their own species, but not those of other species.

The islands of Timur and Wetar, in the Lesser Sunda Islands, are known to be home to a form of Long-tailed Nightjar (Caprimulgus sp.), which is small in size, leading to the suggestion that it might be a population of Caprimulgus manillensis, otherwise known from the Philippines, Caprimulgus celebensis, otherwise known from Sulawesi, or Caprimulgus macrurus, which is distributed from Pakistan to Australia, and generally accepted to be a species complex rather than a single species.

In a paper published in the journal Ibis on 24 June 2024, the late Ben King of the Department of Ornithology at the American Museum of Natural History, George Sangster of the Department of Bioinformatics and Genetics at the Swedish Museum of Natural History, and the Naturalis Biodiversity Centre, Colin Trainor of the College of Engineering, IT and Environment at Charles Darwin University, Martin Irestedt, also of the Department of Bioinformatics and Genetics at the Swedish Museum of Natural History, Dewi Prawiradlilaga of the Museum Zoologicum Bogoriense at the Cibinong Science Centre, and Per Ericson, again of the Department of Bioinformatics and Genetics at the Swedish Museum of Natural History, formally describe the Nightjars found on Timor and Wetar islands as a new species.

King et al. compared recordings of Nightjars from Timor and Wetar to recordings of Nightjars from other areas, finding that these calls were quire distinct. They then compiled a genetic phylogeny for the genus Caprimulgus including two museum specimens collected from Timor and Wetar, again recovering these as a separate species, most closely related to Mees's Nightjar, Caprimulgus meesi, which is found on Flores and Sumba islands, but separated from this by a mean sequence divergence of 5.8%, considered sufficient to differentiate species (the mean sequence divergence between Humans and Chimpanzees is only 1.23%).

The new species is named Caprimulgus ritae in honour of Rita Bobbin, a long-term friend of Ben King. It is described on the basis of four museum specimens in the collections of the American Museum of Natural History and the Naturalis Biodiversity Centre.

Male Caprimulgus ritae, Wetar, 13 October 2014. James Eaton in King et al. (2024). 

Caprimulgus ritae is brownish in colour with a white and cinnamon speckled pattern and a distinct white bar on its tail. It is found only on the islands of Timor and Wetar. It is a forest specialist, although it appears to be quite flexible about the forests it will live in, having been recorded in a range of environments from tall evergreen forest to highly deciduous dry forest. It generally appears to favour lowlands, but has been recorded as high as 1500 m above sealevel. 

The island of Wetar still retains more than 95% of its original vegetation cover, including extensive areas of forest, while both West Timor and Timor-Leste have extensive forest reserves, which appear to form primary habitats for the Nightjar, which King et al. estimate to have a population probably numbered in the hundreds or thousands.

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Comet 13P/Olbers appoaches perihelion.

Comet 13P/Olbers will reach its perihelion (the closest point on its orbit to the Sun) on Sunday 30 June 2024, when it will be approximately 1.18 AU from the Sun (i.e. 118% of the distance from the Sun to the planet Earth, or 176 525 500 km). At this time the comet will be 1.92 AU from the Earth, in the constellation of Lynx, having a magnitude of 6.1, which means that it may be possible to view it from the Northern Hemisphere with a small pair of binoculars in the early evening, although it will be no more than 13° above the horizon at dusk, and set shortly thereafter.

The orbits and relative positions of comet 13P/Olbers and the planets of the Inner Solar System on 30 June 2024. JPL Small Body Database.

Comet 13P/Olbers was discovered by German astronomer Heinrich Wilhelm Matthias Olbers on 26 April 1815.  The designation 13P/Olbers implies that it was discovered by Olbers, that it is a Periodic Comet (defined as a comet with a period of less than 200 years, beyond which it becomes impossible to predict the return of comets reliably), and that it was the 13th such body discovered.

Comet 13P/Olbers observed from Manciano in Italy on 17 June 2024. The image is a composite of fifteen 120 second exposures, taken in the early evening, when the comet was less than 15° above the horizon and the moon was bright. Gianluca Masi/Virtual Telescope Project.

Comet 13P/Olbers has an orbital period of 67.9 years and a highly eccentric orbit tilted at an angle of 44.6° to the plain of the Solar System, that brings it from 1.16 AU from the Sun at closest perihelion (116% of the distance between the Earth and the Sun, and inside the orbit of Mars) to 32.1 AU from the Sun at aphelion (32.1 times as far from the Sun as the Earth or a little outside the orbit of the planet Neptune). As a comet with a period of less than 200 years, 13P/Olbers is considered to be a Periodic Comet, and a comet with a period of more than 20 years but less than 200 years, it is also considered to be a Halley-type comet.

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Friday 28 June 2024

Greco-Roman tombs uncovered near Aswan, Egypt.

A group of Egyptian and Italian archaeologists have uncovered a series of tombs dating to the Greco-Roman period near Aswan in southern Egypt, according to the Egyptian Ministry of Tourism and Antiquities. The archaeologists, from the Egyptian-Italian Mission At West Aswan uncovered the tombs on a series of terraces on a rocky hillside close to the Aga Khan Mausoleum, during a series of excavations in the area following reports of illegal excavation in the area. To date 33 of the tombs have been excavated, with an estimated total of about 300, scattered over an area of about 20 000 m².

A team of Egyptian and Italian archaeologists surveyed the area around the Mausoleum of Aga Khan to map out 300 ancient tombs. Egyptian-Italian Mission At West Aswan/Egyptian Ministry of Tourism and Antiquities.

Significantly, the tombs did not belong to pharaahs or other high ranking individuals, but to ordinary Egyptian families, and were in use between about 900 BC and 300 AD, a period which covers the occupation of Egypt by first the Persian Empire, then the Ptolemaic Greeks, and finally the Romans. Piacentini Patrizia, of the University of Milan, who has been leading the investigations, suggests that during this interval Aswan would have been a prosperous trading centre, connecting Egypt and the Mediterranean world to Nubia and the kingdoms of the African interior.

The interior of one of the newly discovered tombs near Aswan. Egyptian-Italian Mission At West Aswan/Egyptian Ministry of Tourism and Antiquities.

The tombs reveal much about the lives, and particularly the health, of ordinary Egyptians during the period. Between 30% and 40% of the Human remains uncovered so far belong to children and infants, suggesting a fairly high infant-mortality rate. Many of the bodies have pathologies indicative of diseases, including malnutrition, anaemia, tuberculosis and osteoarthritis. Several adult women had undergone limb amputations.

Remains of mummies from the late Greek and Roman period discovered in tombs near Aswan, Egypt. Egyptian-Italian Mission At West Aswan/Egyptian Ministry of Tourism and Antiquities.

Some of the dead from the tombs were buried within coffins or sarcophagi, but many more were preserved as mummies wrapped in linen and covered by painted cartonnages (a kind of papier-mâché made of linen or papyrus and plaster). The tombs have also yielded a wide range of other artefacts, including offering tables, painted statuettes, figurines, and terracotta lamps.

A cartonnage mask, which would have once covered a mummy, from the Aswan Necropolis. Egyptian-Italian Mission At West Aswan/Egyptian Ministry of Tourism and Antiquities.

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Wednesday 26 June 2024

Magnitude 6.0 Earthquake off the north coast of the Paria Peninsula, Venezuela.

The United States Geological Survey recorded a Magnitude 6.0 Earthquake at a depth of 87.4 km, slightly  off the  north coast of the Paria Peninsula on the north coast of Venezuela, slightly before midnight on Sunday 23  June 2024 local time (slightly before 4.00 am on Monday 24 June GMT). This was a large quake, but at some depth as well as offshore, and there are no reports of any casualties or damage, though the quake was felt over a large area, with people reporting feeling it across much of northern Venezuela, and northeastern Guyana as well as on the Caribbean islands of  Trinidad, Granada, St Vincent.

The approximate location of the 24 June 2024 Paria Peninsula Earthquake. USGS.

The Paria Peninsula forms part of the southern margin of the Caribbean Plate, which is moving eastward compared to the South American Plate, upon which the rest of Venezuela sits. This is not a smooth process, the two plates constantly stick together, then break apart as the pressure builds up, causing Earthquakes in the process. 

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Sunday 23 June 2024

Thismia malayana: A new species of Parasitc Plant from Peninsula Malaysia.

Thismias, Thismia spp., are a curious group on Monocotyledonous Plants found in the evergreen forests of tropical and subtropical Asia, northern and eastern Australia to New Zealand, the north-central USA, Costa Rica and southern tropical America. They are Mycoheterotrophs, obtaining nutrition parasitically from the network of Mycorrhizal Fungi which exchange nutrients with the Plants of the forest, but contributing nothing themselves to the relationship. Thismias do not photosynthesize, enabling them to live on the darkest parts of the forest floor, and live most of their lives below ground, occasionally producing intricate, but often inconspicuous, flowers at most a few centimetres high, which are pollinated by Fungus Knats or similar small Insects.

In a paper published in the journal Phytotaxa on 31 May 2024, Mat Yunoh Siti-Munirah of the Forest Research Institute Malaysia, independent researchers Chin Hardy-Adrian, Sharipudin Mohamad-Shafiq, and Zainuddin Irwan-Syah, and Abd Halim Hamidi of the Negeri Sembilan Forestry Department, describe a new species of Thismia from Peninsula Malaysia.

The new species is named Thismia malayana, where 'malayana' is derived from 'Malaya' the old name for Peninsula Malaysia. The species is described from a specimen collected in the Kuala Pilah District of Negeri Sembilan State, Malaysia, on a trail leading to Gunung Angsi mountain, in February 2023.

Thismia malayana (A) flowering plant (A1) floral tube, inner surface (A2) annulus and stamen filaments, view from inside (B) inflorescence with anthetic flower and several young fruits (B1) style and stigma (B2) annulus, top view (C) flower, side view (D), (E) stamens, view from inside and from outside, (E1) stamen supraconnectives: one pair of club-shaped inwards-pointing, one pair of acute outwards-pointing, and one central appendage (F) stamen supraconnectives, apical view (G) stamen tube, view from below (H), (H1) fruit after dehiscence, top view, (H2) seeds I shoot base with roots. Siti-Munirah et al. (2024).

Thismia malayana exists as a vermiform root, light brown, unbranching and about 1 mm in diameter, which produces a light brown herbaceous Plant, reaching a maximum height of about 10 cm. This above-ground Plant comprises a stem about 6 cm long and 0.2 cm in diameter, from which grow 2-4 scale-like brown leaves, and 1-4 asymmetrical, tube-shaped flowers, up to about 7 mm long and 5 mm in width, brown-to-off-white in colour, with orange longitudinal ribs, and an opening surrounded by six triangular tepals. 

Thismia malayana with scales (the finest grade is 0.5 mm) (A) side view (B) top view (C) the size compared to the 20-sen coin (23.59 mm in diameter). Photos by Chin Hardy-Adrian from uncollected plants. Siti-Munirah et al. (2024).
 
Thismia malayana is known from only two localities, one in the Gunung Angsi Forest Reserve in Negeri Sembilan State, and the other in Tengku Hassanal Wildlife Reserve in Pahang State. In both locations it grows in moist, shady areas of Diptocarp forests, at elevations of 200-450 m above sealeavel, usually producing flowers and fruit between December and February (although flowering in June has also been observed). 

Habitat (in situ) of Thismia malayana in Ulu Bendul Recreational Park in Gunung Angsi Forest Reserve (A), (B) and the Tengku Hassanal Wildlife Reserve (C)–(E). (A) Thismia malayana at its habitat, which is located right next to the main trail to Gunung Angsi. (B) Mat Yunoh Siti-Munirah showing the habitat of Thismia malayana. (C) Path to Lata Bujang and Gunung Benom (D) The plants growing on rotten wood (E) Sharipudin Mohamad-Shafiq observing a Thismia malayana in its habitat. Photos by Mat Yunoh Siti-Munirah (A), (B) and Sharipudin Mohamad-Shafiq (C)–(E). Siti-Munirah et al. (2024).

Thismia malayana is known only from two locations, with less than 10 individual Plants observed. Both locations are in protected areas, although on is quite close to a forest trail, where it might be disturbed by visitors. The species is extremely cryptic in nature, making it likely that is exists in other areas and has not been discovered. For these reasons, Siti-Munirah et al. recommend that the species be classified as Vulnerable under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species

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