Two New Species Of Orcovita (Crustacea: Decapoda: Brachyura: Varunidae) From Anchialine Caves On Christmas Island, Eastern Indian Ocean
Author
Davie, Peter J. F.
Author
Ng, Peter K. L.
text
Raffles Bulletin of Zoology
2012
2012-02-29
60
1
57
70
journal article
10.5281/zenodo.4508467
2345-7600
4508467
KEY TO THE GENUS
ORCOVITA
1. Carapace appearing distinctly rectangular; posterolateral margins almost straight, subparallel, not distinctly convergent towards posterior carapace margin ..................................................... 2
– Carapace appearing more hexagonal; posterolateral margins concave, distinctly convergent towards posterior carapace margin .................................................................................... 3
2. Junction between antero- and posterolateral margins rounded; posterolateral margin smooth; lengths of 3P and 4P propodus 4.3 and 3. 1 times width, respectively, lengths of 3D and 4D 7.8 and 5.5 times width, respectively (Kakaban:
Indonesia
) .. ...............................................................................
O. saltatrix
– Junction between antero- and posterolateral margins angular; posterolateral margin granulated; lengths of 3P and 4P 5.4 and 3.7 times width, respectively, lengths of 3D and 4D 16.1 and 6.6 times width, respectively (Coron:
Philippines
) ................. ..............................................................................
O. angulata
3. Male chela with thick patch of setae at base of gape; exorbital tooth always clearly separated from rest of anterolateral margin by deep, distinct cleft, margin never entire ……………………………………………… 4
– Male chela without an obvious thick patch of setae at base of gape (at most some sparse short setae along edge; exorbital tooth separated from rest of anterolateral margin by small cleft, sometimes absent, with margin appearing almost entire ...... 8
4. Anterolateral margins with 2 teeth behind exorbital angle (second may be reduced to only a broad lobe) .................................. 5
– Anterolateral margins with only a single distinct tooth behind exorbital angle (Loyalty Islands) ......................
O. mcneiceae
5. Carapace relatively broad (ca. 1.4 times wider than long); ambulatory legs relatively longer, more slender (4M ca. 5.7 times longer than wide) (
Niue
) .........................
O. gracilipes
– Carapace narrower (ca. 1.2 times wider than long); ambulatory legs relatively shorter (4M ≤4.3 times longer than wide) .... 6
6. Anterolateral teeth both acute; ambulatory legs relatively short, stout (4M 3.9 times longer than wide); sixth male abdominal somite about 2.3 times wider than long; male telson 1.5 times length of sixth abdominal somite ........................
O. holthuisi
– Anterolateral teeth broadly rounded; ambulatory leg proportions not as above; sixth male abdominal somite about twice as wide as long; male telson 1.1-1.2 times length of sixth abdominal somite .................................................................................... 7
7. Anterolateral teeth both clearly defined, similar in prominence (Ryukyus:
Japan
) ....................................................
O. miruku
– First anterolateral teeth deeply notched, prominently projecting, second tooth in form of broad lobe, not defined by distinct notch (Christmas Is.) .........................
O. orchardorum
,
new species
8. Ambulatory legs relatively long, slender, length of 3P about 5 times width or more .............................................................. 9
– Ambulatory legs relatively shorter, length of 3P 4.2 times width, lengths of 3D and 4D 9.1 and 6.2-6.9 times width, respectively (Panglao:
Philippines
) .............................................
O. fictilia
9. Supraorbital margin relatively straight, without distinct lateral concavity such that exorbital tooth low, not appearing markedly produced; anterolateral tooth of carapace marked by only indistinct notch, or obsolete; length of 3P 5.2 times width, lengths of 3D and 4D 12.9 and 7.6 times width, respectively; small species (<
15 mm
c.b.) (
Guam
) ..................
O. mollitia
– Supraorbital margin sinuous, markedly concave laterally such that exorbital tooth appears more prominently produced; single anterolateral tooth of carapace marked by strong V-shaped notch; length of 3P 4.8 times width, lengths of 3D and 4D 11.0 and 6.4 times width, respectively; larger species (>
15 mm
c.b.) (Christmas Is.) .....................................
O. hicksi
,
new species