Hemigrapsus crenulatus

Last updated

Contents

Hemigrapsus crenulatus
Hairy handed crab Hemigrapsus crenulatus.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Brachyura
Family: Varunidae
Genus: Hemigrapsus
Species:
H. crenulatus
Binomial name
Hemigrapsus crenulatus
Synonyms   [1]
  • Trichodactylus granariusNicolet, 1849
  • Trichodactylus granulatusA. Milne-Edwards, 1853
  • Heterograpsus barbigerusHeller, 1862
  • Heterograpsus barbimanusHeller, 1865
  • Heterograpsus sanguineusLenz, 1902

Hemigrapsus crenulatus, the hairy-handed crab or papaka huruhuru, [2] is a marine crab of the family Varunidae, endemic to the New Zealand coast, although a taxon in Chile may be conspecific. [3] It is an intertidal species with semi-terrestrial tendencies. They are named by their characteristic setae, or patches of thick hair, on the chelipeds and legs. [4] They can range from green to brown in coloration. Adult crabs are generally 2–4 cm (0.8–1.6 in) wide at the carapace, [5] although the smallest mature crabs can be around just 1 cm (0.4 in) wide. [6] and are able to survive and reproduce in environments of widely varying salinities. [7]

History

There have been disputes throughout history about whether the two geographically distant populations were truly of the same species, beginning with Milne-Edwards' initial identification in 1837. He had access to specimens from both regions but did not specify the origin of the species he had named. [5] With the ambiguous nature of this identification, in the following century, a series of further research comparing specimens from both New Zealand and Chile would introduce competing perspectives, specifically due to a small anatomical discrepancy. There was a slight difference in a ridge below the eyes, known as the stridulating ridge. [8] A few names, now synonymous, have been given to both populations in the past. [8] [9] Mary J. Rathbun was the first to compare specimens from New Zealand and Chile and support the traditional view of a single species in 1918. [10] This view was confirmed in 2011 through extensive morphological and genetic analysis. [5]

Reproduction and Growth

The breeding season spans from June to January or February, with winter breeding being more common than summer breeding. [4] [6] The females are ovigerous, meaning they will carry the eggs on their undersides. [4] Females are also capable of breeding twice within a season. Molting is generally concentrated before and after the breeding season. In perfect conditions of temperature and salinity, the minimum incubation time for the eggs was 45 days, with time and egg size tending to increase with lower salinity. [6]

During the process of maturation, defined as possessing the ability to reproduce, male carapaces develop circularly while female carapaces develop elliptically, in a horizontal manner. This is done to increase the width of the abdomen in order to hold more eggs. The minimum carapace width of mature males is 1.3–1.5 cm (0.5–0.6 in) and that of mature females is 0.9–1.1 cm (0.3–0.4 in), with the general range being 1.2–2.0 cm (0.5–0.8 in). Mostly males account for the deviations outside this range. [6] Males will also grow for longer, faster, and larger than females, potentially up to twice the initial mature size. [5]

Appearance and Anatomy

Males and females are quite similar in appearance, both having a circular carapace that is slightly wider than it is long from the dorsal view. [6] [5] The New Zealand crabs are more green in coloration while the Chilean crabs are more brown. An array of pale spots can be seen on the carapace in a similar pattern for both sexes. Adult crabs have carapace widths of 2–4 cm (0.8–1.6 in) when they are fully grown. [5] Small granules, or protrusions, can be seen on the shell from the ventral view towards the front of the crab. Eye sockets are wide. Few small teeth can be seen along the rim of the front sides of the carapace. Male appendages tend to be more pilose (hairy) at the base of the claws and along the lengths of the legs. The thickness of the hair sometimes even interferes with the operation and function of the claw. The outer surface of the claw is granulate, with the fixed finger of the claw bent downwards and into the palm. The arm is triangular and has a transverse row of granules extending across the ventral surface. [4]

The stridulating ridge, a ridge situated below and across both eyes, can be seen from the anterior-posterior view. It is continuously granulate in females, but the patterning is more segmented in males. [4] Variations to this cross-sex positioning of granules and lobes was used in some arguments against the crabs from New Zealand and Chile being the same species. [8]

Ecology and Behavior

H. crenulatus can be found throughout mainland New Zealand [4] as well as the west coast of Chile. [11] They are euryhaline, meaning they are able to survive in environments with a wide range of salinities. These may include estuaries, brackish waters, and the intertidal. In one incidence reported by E.F. Stead, between 1910 and 1912, after a storm had introduced a large influx of salt water to a freshwater lake, H. crenulatus populated the surroundings until the salt levels resolved. [4] In the intertidal, there are rarely any below the low-water mark, although female crabs predominate at the lower levels. [4] [12]

They characterized as burrowing crabs, as they will hide under stones or burrow into sand and mud. Thus, they prefer softer substrates to help them avoid conditions of intense light, high temperatures, and high salinities. [13]

The semi-terrestrial aspect of these crabs means they will spend time away from the shore. For example, they will migrate up the shore along with the rising tide to feed in terrestrial areas at high tide before retreating with the falling water levels. [12]

Related Research Articles

<span class="mw-page-title-main">Fiddler crab</span> Genus of crabs

The fiddler crab or calling crab may be any of more than one hundred species of semiterrestrial marine crabs in the family Ocypodidae, well known for their sexually dimorphic claws; the males' major claw is much larger than the minor claw, while the females' claws are both the same size. A smaller number of ghost crab and mangrove crab species are also found in the family Ocypodidae. This entire group is composed of small crabs, the largest being slightly over two inches (5 cm) across. Fiddler crabs are found along sea beaches and brackish intertidal mud flats, lagoons, swamps, and various other types of brackish or salt-water wetlands.

<i>Hemigrapsus sexdentatus</i> Species of crab

Hemigrapsus sexdentatus, also called the “common rock crab” or “common shore crab,” is a marine crab indigenous to the southern shores of New Zealand. This crab is a member of the Varunidae family in the order Decapoda.

<i>Cyclograpsus lavauxi</i> Species of crab

The Smooth Shore Crab is a marine large-eyed crab of the family Grapsidae, found in New Zealand and the Juan Fernández Islands of Chile.

<i>Leptograpsus</i> Genus of crabs

Leptograpsus variegatus, known as the purple rock crab, is a marine large-eyed crab of the family Grapsidae, found in southern subtropical Indo-Pacific Oceans. It grows to around 50 millimetres (2.0 in) shell width. It is the only species in the genus Leptograpsus.

<i>Hemigrapsus sanguineus</i> Species of crab

Hemigrapsus sanguineus, the Japanese shore crab or Asian shore crab, is a species of crab from East Asia. It has been introduced to several other regions, and is now an invasive species in North America and Europe. It was introduced to these regions by ships from Asia emptying their ballast tanks in coastal waters.

<i>Ovalipes catharus</i> Species of crab

Ovalipes catharus, commonly known as paddle crab and Māori: pāpaka, is a species of crab of the family Portunidae. It is found around the coasts of New Zealand, the Chatham Islands, and in south-eastern parts of Australia. Individuals from shallow waters, 0.1–0.5 metres (4–20 in) deep, have a carapace width of only 10–15 millimetres (0.4–0.6 in), while those from 5–15 m (16–49 ft) are 100–140 mm (3.9–5.5 in) wide.

<i>Notomithrax ursus</i> Species of crab

Notomithrax ursus, known as the hairy seaweed crab, is a spider crab of the family Majidae.

<span class="mw-page-title-main">Purple shore crab</span> Species of crab

The purple shore crab is a common crab of the family Varunidae that is indigenous to the west coast of United States, Canada, and Mexico. H. nudus was first described in 1847 by Adam White, and in 1851, James Dwight Dana formally classified the species. H. nudus is a small, amphibious crab that is similar physically and behaviorally to Pachygrapsus crassipes and Hemigrapsus oregonensis. The purple shore crab is generally a dark purple color with olive green, red, and white spots. Mating season for H. nudus begins in mid-winter and larval crabs undergo 5 zoeal stages and a juvenile stage. Adult crabs mainly feed on algae but will occasionally scavenge other animals. H. nudus prefers inter-tidal and sub-tidal zones, and it can oftentimes be found sheltering under rocks or other debris. H. nudus demonstrates complex compensatory mechanisms to counteract fluctuating salinity and water oxygen concentrations, permitting it to live in a variety of different environments.

<i>Hemigrapsus oregonensis</i> Species of crab

Hemigrapsus oregonensis is a small shore crab of the family Varunidae; formerly classified under the family Grapsidae. It is known under several common names, including yellow shore crab, hairy shore crab, green shore crab, mud-flat crab, bay shore crab and Oregon shore crab. Despite its common name, the crab actually has a wide variety of coloration. It is found along the West Coast of the United States and Canada, specifically along shorelines and similar geographical areas. In 2009, H. oregonensis was included on a list of animals petitioning for the endangered species label, but there was not enough scientific information available for it to be considered as such, so it remains unevaluated to the present day.

<i>Hemigrapsus takanoi</i> Species of crab

Hemigrapsus takanoi, the brush-clawed shore crab or Asian shore crab, is a small crab of the family Varunidae that lives on rocky shores surrounding the Pacific Ocean, and which is invasive along the European coastlines. This crab is omnivorous and eats small fish, invertebrates and algae.

<i>Heloecius</i> Genus of crabs

Heloecius cordiformis is a species of semiterrestrial crab found in mangrove swamps and mudflats along the east coast of Australia. Adults are around 25 mm (1 in) wide, with males being larger and having larger and more conspicuously coloured claws. The males wave their claws to communicate with other crabs, giving them their common name of semaphore crab. They can breathe both in air and under water, and feed at low tide on detritus in the sediment. H. cordiformis is the only species in the genus Heloecius and the family Heloeciidae.

<i>Ocypode gaudichaudii</i> Species of crab

Ocypode gaudichaudii, also known as the painted ghost crab or cart driver crab, is a species of crab found on Pacific beaches from El Salvador to Chile as well as on the Galápagos Islands. The species was first described by Henri Milne-Edwards and Hippolyte Lucas in 1843.

<i>Hemigrapsus estellinensis</i> Extinct species of crab

Hemigrapsus estellinensis is an extinct species of crab, formerly endemic to the Texas Panhandle. It was discovered by Gordon C. Creel in 1962 and was probably already extinct before his description was published in 1964, after the Estelline Salt Springs where it lived were contained by the United States Army Corps of Engineers. H. estellinensis is closely related to species from the Pacific Ocean such as Hemigrapsus oregonensis, but lived 800 km (500 mi) inland in a hypersaline spring. It differed from its relatives by the pattern of spots on its back, and by the relative sizes of its limbs.

<i>Hemigrapsus</i> Genus of crabs

Hemigrapsus is a genus of varunid crabs comprising thirteen species native almost exclusively in the Pacific Ocean, but two have been introduced to the North Atlantic region.

<i>Chionoecetes opilio</i> Species of crab

Chionoecetes opilio, a species of snow crab, also known as opilio crab or opies, is a predominantly epifaunal crustacean native to shelf depths in the northwest Atlantic Ocean and north Pacific Ocean. It is a well-known commercial species of Chionoecetes, often caught with traps or by trawling. Seven species are in the genus Chionoecetes, all of which bear the name "snow crab". C. opilio is related to C. bairdi, commonly known as the tanner crab, and other crab species found in the cold, northern oceans.

<i>Guinotellus</i> Genus of crabs

Guinotellus melvillensis is a species of crabs in the family Xanthidae, the only species in the genus Guinotellus. It is a benthic crab with an ovate carapace within the subfamily Euxanthinae.

<i>Dyspanopeus sayi</i> Species of crab

Dyspanopeus sayi is a species of mud crab that is native to the Atlantic coast of North America. It has also become established outside its native range, living in Swansea Docks since 1960, the Mediterranean Sea since the 1970s, the North Sea since 2007 and the Black Sea since 2010. It can reach a carapace width of 20 mm (0.8 in), and has black tips to its unequal claws. It feeds on bivalves and barnacles, and is in turn eaten by predators including the Atlantic blue crab, Callinectes sapidus. Eggs are produced from spring to autumn, the offspring reach sexual maturity the following summer, and individuals can live for up to two years. The closest relative of D. sayi is D. texanus, which lives in the Gulf of Mexico; the two species differ in subtle features of the genitalia and the last pair of walking legs.

Perisesarma guttatum, the red-claw mangrove crab, is a crab species in the genus Parasesarma and the family Sesarmidae. It is distributed in coastal brackish water habitats of the western Indian Ocean.

<i>Pseudohelice subquadrata</i> Species of crab

Pseudohelice subquadrata is a species of crab in the family Varunidae. It is found from the eastern Indian Ocean to the western Pacific Ocean, north to Japan, south to Eastern Australia, east to French Polynesia, west to Indonesia and Thailand. It lives near mangroves, burrowing in firm soils, firm muddy sand or loose stones. Burrows are towards or above the high tide line on shores of estuaries and near river mouths of bays, and can have offshoots horizontal beneath the surface as long as three metres.

References

  1. Peter K. L. Ng; Danièle Guinot & Peter J. F. Davie (2008). "Systema Brachyurorum: Part I. An annotated checklist of extant Brachyuran crabs of the world" (PDF). Raffles Bulletin of Zoology . 17: 1–286. Archived from the original (PDF) on 2011-06-06.
  2. Peter K. L. Ng; Danièle Guinot & Peter J. F. Davie (2008). "Systema Brachyurorum: Part I. An annotated checklist of extant Brachyuran crabs of the world" (PDF). Raffles Bulletin of Zoology . 17: 1–286. Archived from the original (PDF) on 2011-06-06.
  3. "Hemigrapsus crenulatis[sic] (H Milne Edwards, 1837), hairy-handed crab, papaka huruhuru". Seafriends. Retrieved October 22, 2010.
  4. 1 2 3 4 5 6 7 8 Bennett, E.W. (1964). The marine fauna of New Zealand: Crustacea Brachyura. New Zealand Department of Scientific and Industrial Research (Bulletin 153) [Also published as New Zealand Oceanographic Institute Memoir 22.]
  5. 1 2 3 4 5 6 McLay, Colin L.; Hinnendael, Francis; Lavery, Shane; Riquelme-Bugueño, Ramiro B. (October 2011). "Morphological and Molecular Comparison of Hemigrapsus crenulatus (Milne Edwards, 1837) (Brachyura: Varunidae) from New Zealand and Chile: Was Miss Rathbun Right?". Journal of Crustacean Biology. 31 (4): 582–589. doi: 10.1651/11-3494.1 . ISSN   0278-0372. S2CID   84625206.
  6. 1 2 3 4 5 Clark, Rachel Louise (1987). Aspects of growth and reproduction of the hairy handed crab, Hemigrapsus crenulatus (Brachyura : Grapsidae) (MSc). University of Canterbury. doi:10.26021/8514.
  7. Hoskins, R. H. (1966). Sodium ion regulation in two bivalves and two crabs [Scholarly project]. In University of Canterbury. Retrieved March 26, 2021.
  8. 1 2 3 Bennett, E. W. 1930. Notes on New Zealand Brachyura and related crustaceans. Records of the Canterbury Museum 3: 255-261.
  9. Gay, Claudio; Johnston, I. M. (1844). Historia fisica y politica de Chile segun documentos adquiridos en esta republica durante doce anos de residencia en ella y publicada bajo los auspicios del supremo gobierno. Paris :||Chile, en el Museo de historia natural de Santiago: En casa del autor.
  10. Rathbun, Mary J. (1918). "The grapsoid crabs of America". Bulletin of the United States National Museum (97): i–461. doi:10.5479/si.03629236.97.i. hdl:10088/10180.
  11. Vega-Aguayo, Rolando; Figueroa-Muñoz, Guillermo; Retamal, Marco A.; De los Ríos, Patricio (2018). "Spatial distribution and abundance of Hemigrapsus crenulatus (H. Milne Edwards, 1837) (Decapoda, Varunidae) in the Puerto Cisnes estuary (44°S, Aysen region, Chile)". Crustaceana. 91 (12): 1465–1482. doi:10.1163/15685403-00003841. ISSN   0011-216X.
  12. 1 2 Walker, E. A. (1970). Distribution of three species of intertidal crabs [Scholarly project]. In University of Canterbury. Retrieved March 26, 2021.
  13. Jones, M. B. (December 1976). "Limiting factors in the distribution of intertidal crabs (Crustacea: Decapoda) in the avon-heathcote estuary, christchurch". New Zealand Journal of Marine and Freshwater Research. 10 (4): 577–587. doi: 10.1080/00288330.1976.9515641 . ISSN   0028-8330.