New find of Houia (Arthropoda: Euchelicerata) from the Lower Devonian of Guangxi, South China

Abstract

Houia is a possible annectent form between horseshoe crabs and eurypterids (sea scorpions). However, fossils are rare, previously only known from a single locality. Here, we report a new species of this genus, Houia guangxiensis sp. nov., from the Lower Devonian Cangwu Formation of Guangxi Province, South China. This discovery extends the geographical distribution of Houia from the Yangtze to the Cathaysia Block, supporting the living age of this genus in the Early Devonian (Lochkovian-Emsian). It not only adds to the record of this rare 'intermediate' form but also suggests potential relationships of shallow-water species in the Yangtze and Cathaysia blocks.

New insights into the South China Lower Devonian flora based on fossils from Hezhang, Guizhou Province

“…All plant fossils were preserved in coastal or near shore settings, the palaeoenvironment of which can also be verified by shallow marine fossils associated with the plants, such as the Limulus from the Lower Devonian of both eastern Yunnan (zone I) and Cangwu (zone III), with the presumed dispersal of the animals through sea [55]. However, all the Early Devonian plants were terrestrial and spore bearing, such that their dispersal relies on spore spreading by means of wind.…”

Shallow-marine testate amoebae with internal structures from the Lower Devonian of China

“… 13 Our testate amoeba co-occurs with several types of plant remains and more recently reported Houia (Euchelicerata) ( STAR Methods ), the latter of which has been considered to live in marine habitats. 67 , 68 , 69 It can be suggested that the fossil-bearing horizon represents a shallow-water marine environment ( Figure 4 ). Our fossils, then, would play a significant role in extending the record of marine VSMs into the Early Devonian, during which the earliest freshwater testate amoebae occurred.…”

“… 74 Recently, the euchelicerate Houia was found in the Shiqiaofeng Member of the Cangwu Formation. 67 In the overlying Hanzhen Formation, more animal fossils have been reported, including bivalves Glossites sp., Leptodesma schiqiaoensis , Modiomorpha sp. and Praecardium sp., and a species of ostracod— Paramoelleritia xiangzhouensis 75 , 76 that is regarded to indicate an age from late Emsian to Eifelian.…”

Silurian freshwater arthropod from northwest China

“…2015; Wang et al . 2021), they were all buried in the littoral environment or marine tidal flats, suggesting that these Devonian arthropods could not completely live out of the sea. In this paper, we describe a new species of freshwater arthropod from the late Silurian strata in western Junggar, Xinjiang, northwest China, and discuss its implications for the origin and evolution of early non‐marine arthropods.…”