Justicia cubangensis & Justicia eriniae: Two new species of Water Willow from south-central Angola.

Water Willows, Justicia, are perennial herbs and shrubs found in tropical, sub-tropical, and warm temperate regions of the Americas, Africa and India. They typically have heavily veined leaves and white, cream, yellow, orange, or pink tubular flowers, which are attractive to Butterflies, making them widely cultivated as ornamental flowers, though they are not hardy and need to be kept under glass in areas prone to frosts. The genus Justicia is the largest in the family Acanthaceae, and was recently expanded to include the genus Monechma, after that genus was found to contain plants which were morphologically similar to one-another but not genetically monophyletic (i.e. not all sharing a common ancestor which isn't also the ancestor of other plants which are not placed within the genus), and it is likely that other genera will also be subsumed by Justicia in the future.

In a paper published in the journal Blumea on 3 May 2019, Iain Darbyshire of the Royal Botanic Gardens at Kew, and David Goyder of the National Geographic Okavango Wilderness Project at the Wild Bird Trust, describe two new species of Justica from southern Angola.

The first new species is named Justicia cubangensis, meaning 'from Cubanga' in reference to the Cubango River drainage, where it was discovered, part of the upper catchment of the Okavango system in Angola. This plant forms erect or trailing perennial herbs, 15-65 cm high, with annual branching stems arising from a woody base. The stems are quadrangular and hairy, the leaves lance shaped and up to 46 mm in length. Flowers are born on a spike 25-70 mm long and are 12–13 mm long and cream-white in colour, with the palate of the lower lip pink with white veins in raised ‘herring-bone’ pattern. The species was found in Cuando Cubango and Huíla provinces, growing in open grasslands within areas of Miombo (flood-plain) woodland. It was observed at only three locations, and was not abundant at any of these, but may be more widespread as Angola has been under-explored by botanists to date.

Justicia cubangensis. David Goyder in Darbyshire & Goyder (2019).

The second new species described is named Justicia eriniae, in honour of Erin Tripp of the Museum of Natural History at the University of Colorado, who collected the first specimen of this species. This is a brittle-stemmed herb reaching 50-75 cm in height, which has blade-shaped leaves up to 65 mm in length. and produces tubular flowers 18-18.5 mm in length on a flower spike 5.5-8.0 cm high. A single patch of these plants, less than 10 in number, was found growing by a road in Namibe Province, southwest Angola, in an area of lowland thornscrub, though it is unclear if this means the species is rare, since the area is poorly explored.

Justicia eriniae. David Goyder in Darbyshire & Goyder (2019).

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Ceratogyrus attonitifer: A new species of Horned Baboon Spider from Angola.

Baboon Spiders, Harpactirinae, are large Mygalomorph Spiders (Tarantulas) found in Africa. They inhabit silk-lined burrows on the ground, from which they ambush prey, and which they will defend aggresively against any percieved threat with a painful venemous bite; this bite is reputed to be so painful that even Baboons will leave these Spiders alone. Members of the genus Ceratogyrus are widespread in Southern Africa, and are given the popular name Horned Baboon Spiders due to a large foveal horn found on the sternum of some species.

In a paper published in the jouranl African Invertebrates on 6 February 2019, John Midgley of the National Geographic Okavango Wilderness Project of the Wild Bird Trust, the Department of NaturalSciences at the KwaZulu-Natal Museum, and the Southern African Forensic Entomology Research Laboratory at Rhodes University, and Ian Engelbrecht of the South African National Biodiversity Institute and the Department of Zoology and Entomology at the University of Pretoria, describe a new species of Ceratogyrus from the Okavango catchment of Angola.

The Okavango wetland system is best known from Botswana, where it has been a major tourist attraction for decades, as well as being home to numerous scientific studies and television documentaries, but the system actually falls across three counries, Botswana, Namibia and Angola, with the majority in Angola. This Angolan part of the Okavango has recieved relatively little outside attention due ro a civil war that statrted shortly after the collapse of the Portuguese colonial empire in 1974, and lasted into the twenty first century. The National Geographic Okavango Wilderness Project has been working in the area since 2015, and aims to study the entire ecosystem across the three nations of the Okavango, and promote conservation in the area.

The new species is named Ceratogyrus attonitifer, which means 'bearer of astonishment' in reference to the surprise invoked by the discovery of this Spider. The species is described from six female specimens, collected from an undisclosed location within Moxico Province, Angola, during a National Geographic Okavango Wilderness Project in 2016. These are 20.8-40.5 mm in length and golden brown in colour, with the foveal horn much larger than seen in any previously seen member of the genus Ceratogyrus, and soft rather than rigid in nature.

Ceratogyrus attonitifer. (A) Retrolateral view, (B) dorsal view, (C) ventral view. Scale bars are 10 mm. Midgley & Engelbrecht (2019).

Ceratogyrus attonitifer is found in burrows in sandy soil in open Miombo woodland in southeastern Angola. These burrows are near vertical and about 40 cm deep, with a horizonal section at the base. The burrow has a silk colar with local materials such as twigs or grass incorporated. Any object inserted into the burrow was attacked enthusiastically. The Spiders principally feed on Insects, though local people report that the bites can be  serious, and even potenrially fatal if medical help is not available.

Habitat, burrow and live habitus of Ceratogyrus attonitifer in south-eastern Angola. (A) Aerial view of habitat at the type locality showing a dambo (wetland) amongst Miombo (Brachystegia) woodland. The expedition campsite is to the right of the dambo. Specimens were collected primarily along the margins of the wetland area. (B) Live habitus, dorsal, showing full size of the foveal protuberance in life. (C) Specimen in defensive posture typical for Baboon Spiders; background is white sand at the type locality. (D) Burrow entrance amongst grass tussocks; entrance approximately 2 cm wide. Midgley & Engelbrecht (2019).

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