Porirualia megarostrum, comb. nov.

• Main Authors: Huys, Rony, Mu, Fanghong
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2021
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Hexanauplia; Harpacticoida; Parastenheliidae; Porirualia; Porirualia megarostrum; Antarc*; Antarctica
• Online Access: https://doi.org/10.5281/zenodo.5572482; http://treatment.plazi.org/id/951887EAFF80FFDAFF51D602E723FD16

Porirualia megarostrum (Wells, Hicks & Coull, 1982) comb. nov. Parastenhelia megarostrum Wells, Hicks & Coull, 1982 Original description. Wells et al. (1982): 159–164; Figs 5–6; Table 2. Type locality. New Zealand, North Island, Wellington; Porirua Harbour, Pauatahanui Inlet (since renamed to Te Awarua-o-Porirua Harbour); intertidal beach some 200 m north-east of the State Highway 1 bridge; fine sand with some silt. Differential diagnosis . This coincides with Wells et al. ’s (1982) excellent description of Parastenhelia megarostrum . See below for differences with its only congener, Po. pyriformis comb. nov. Notes. Wells et al. (1982) remarked that, despite discrepancies in his illustrations, based on locality and collection details, it appears that Thomson’s (1883) Thalestris forficula is conspecific with Po. megarostrum comb. nov. This claim is considered highly unlikely for a variety of reasons: (a) Thomson’s female specimens are significantly larger (1 mm vs 665 μm); (b) there is no mention of the large rostrum which is one of the most conspicuous characters of Po. megarostrum comb. nov. (c) the antennule is more slender; (d) P1 exp-2 is elongate, about 2.5 times the length of exp-1 ( vs subequal to exp-1); and (e) P1 enp-1 is comparatively longer and its inner seta shorter. Thomson (1883) also stated that the central caudal setae (seta V) are “… swollen just beyond their basal articulation, and marked along the greater part of their length with annular articulations” while in Po. megarostrum comb. nov. all caudal ramus setae are unmodified. As stated above it is conceivable that T. forficula sensu Thomson (1883) is conspecific with Microthalestris antarctica comb. nov. Porirualia megarostrum comb. nov. is so far endemic to New Zealand where it is found on fine silty intertidal sandbanks in practically all of the country’s major estuarine and harbour systems (Wells et al. 1982; Wells & Hicks in Dahms & Hicks 1996). Additional records from Porirua Harbour, including Pauatahanui Inlet, have ...