Microgloma nhanduti
| Notice: | This page is derived from the original publication listed below, whose author(s) should always be credited. Further contributors may edit and improve the content of this page and, consequently, need to be credited as well (see page history). Any assessment of factual correctness requires a careful review of the original article as well as of subsequent contributions.
If you are uncertain whether your planned contribution is correct or not, we suggest that you use the associated discussion page instead of editing the page directly. This page should be cited as follows (rationale):
Citation formats to copy and paste
BibTeX: @article{Benaim2011ZooKeys152, RIS/ Endnote: TY - JOUR Wikipedia/ Citizendium: <ref name="Benaim2011ZooKeys152">{{Citation See also the citation download page at the journal. |
Ordo: Nuculanoida
Familia: Nuculanidae
Genus: Microgloma
Name
Microgloma nhanduti Benaim & Absalão, 2011 sp. n. – Wikispecies link – ZooBank link – Pensoft Profile
Holotype
MNRJ 19.113 (Figs 26, 28).
Type locality
Campos Basin, #54, 12/12/2002, 750m, 21°57'17,5"S, 39°56'01,1"W.
Paratypes
IBUFRJ 14991 (# 54, 2002), 2 valves and 1 specimen; IBUFRJ 19176 (# 64, 2003), 1 specimen; MZSP 99980 (# 54, 2002), 5 valves; USNM 1156944 (# 54, 2002), 5 valves; MNHN 24597 (# 54, 2002), 2 valves 1 specimen.
Etymology
Nhanduti is a Tupi–Guarani term (the language spoken by the largest groups of native people living in Brazil prior to the European colonization) for a spider web–like structure, similar to those present on the prodissoconch of this species. The species epithet is proposed as a noun in apposition.
Material examined
IBUFRJ 15140 (# 69, 2002), 17 valves and 2 specimens; IBUFRJ 15283 (# 69, 2002), 6 valves; IBUFRJ 19115 (# 33, 2002), 1 valve; IBUFRJ 19116 (# 64, 2002), 16 valves and 1 specimen; IBUFRJ 19117, (# 49, 2003), 7 valves; IBUFRJ 19118, (# 54, 2003), 1 valve; IBUFRJ 19119, (# 59, 2003), 10 valves and 2 specimens; IBUFRJ 19121, (# 34, 2002), 1 valve; IBUFRJ 19122, (# 37, 2002), 1 valve; IBUFRJ 19123, (# 38, 2002), 1 valve; IBUFRJ 19124, (# 64, 2003), 12 valves and 1 specimen; IBUFRJ 19125, (# 75, 2003), 2 valves; IBUFRJ 19126, (# A7, 2008), 4 specimens; IBUFRJ 19127, (# A7, 2008), 1 valve; IBUFRJ 19128, (# A7, 2008), 1 valve and 3 specimens; IBUFRJ 19129, (# D7, 2008), 1 specimen; IBUFRJ 19130 (# H7, 2008), 2 specimens; IBUFRJ 19131 (# D6, 2008), 3 specimens; IBUFRJ 19132 (# H7, 2008), 1 specimen; IBUFRJ 19133 (# H7, 2008), 4 valves; IBUFRJ 19134 (# D6, 2008), 1 specimen; IBUFRJ 19135 (# I7, 2008), 1 specimen; IBUFRJ 19136 (# A7, 2009), 2 specimens; IBUFRJ 19137 (# A7, 2009), 6 specimens; IBUFRJ 19138 (# D6, 2009), 4 specimens; IBUFRJ 19139 (# H7, 2009), 10 specimens; IBUFRJ 19140 (# CANAC7, 2009), 5 specimens and 2 valves; IBUFRJ 19141(# CANAC7, 2008), 1 specimen; IBUFRJ 19142 (# I7, 2008), 2 specimens; IBUFRJ 19143 (# CANAC7, 2008), 6 specimens; IBUFRJ 19144 (# D7, 2008), 1 specimen.
Diagnosis
Shell minute, ovate. Entire margin slightly thickened. Hinge plate moderately thick. Prodissoconch with web–like striae.
Description
Shell minute, ovate, H/L ratio about 0.78 (n 29, min 0.74, max 0.81), Width of both valves/H ratio about 0.7 (n 11, min 0.67, max 0.77), inequilateral, translucent, glossy; umbones moderately prominent, large, posterior to midline, orthogyrous. Antero–dorsal margin convex and oblique; anterior margin rounded and projected. Antero–ventral margin convex, postero–ventral margin shorter and rising up to short and rounded posterior end; postero–dorsal margin convex, but forming a small shoulder. Entire shell margin slightly thickened. Surface with subtle commarginal growth lines. Hinge plate with 5–7 anterior and 4–5 posterior teeth, interrupted by a shallow rectangular hinge plate. Width of both anterior and posterior row of teeth occupies about 70% of width of hinge plate, which is thick for its size (whp/H approximately 0.14). Posterior part of the hinge plate shorter than anterior one. Prodissoconch surface nacreous, with several radial striae, resembling a spider’s web. Prodissoconch length approximately 246 µm.Maximum adult shell length 1.16 mm. {| class="wikitable" ; style="width: 100%" |+ Table 4. Measurements of the type material. * Width = width of a single valve. |- ! Microgloma nhanduti sp. n. |- ! !! Length !! Height !! Width* |- | MNRJ 19.113 || 1.12 || 0.90 || 0.29 |- | IBUFRJ 14.991 || 1.11 || 0.84 || 0.24 |- | IBUFRJ 14.991 || 1.04 || 0.82 || 0.29 |- | IBUFRJ 14.991 || 1.09 || 0.89 || 0.29 |- | IBUFRJ 19.176 || 1.13 || 0.89 || 0.29 |- | MZSP 99.980 || 1.09 || 0.82 || 0.29 |- | MZSP 99.980 || 1.09 || 0.82 || 0.27 |- | MZSP 99.980 || 0.98 || 0.76 || 0.24 |- | MZSP 99.980 || 1.09 || 0.82 || 0.27 |- | MZSP 99.980 || 1.11 || 0.82 || 0.27 |- | MZSP 99.980 || 1.11 || 0.84 || 0.22 |- | USNM 1156944 || 1.11 || 0.87 || 0.27 |- | USNM 1156944 || 1.11 || 0.87 || 0.29 |- | USNM 1156944 || 0.96 || 0.78 || 0.27 |- | USNM 1156944 || 1.07 || 0.80 || 0.24 |- | USNM 1156944 || 1.11 || 0.89 || 0.27 |- | MNHN 24596 || 1.07 || 0.87 || 0.22 |- | MNHN 24596 || 1.07 || 0.87 || 0.22 |- | MNHN 24596 || 1.09 || 0.80 || 0.22 |}
Remarks
Microgloma nhanduti sp. n. is similar to Microgloma pusilla and Microgloma tumidula in the oval outline. but has more prominent umbones (Figs 26–28). Compared to Microgloma macaron sp. n. and Microgloma yongei, Microgloma nhanduti sp. n. has a more elongated outline, a longer anterior area, and a more evident prodissoconch sculpture, with a web–like pattern (Figs 29–30). In Microgloma nhanduti sp. n. the umbo is not as prominent and the shell margin not as thick as in Microgloma macaron sp. n.Untill now this species is reccorded solely in Campos Basin.
Original Description
- Benaim, N; Absalão, R; 2011: Microgloma Sanders & Allen, 1973 (Nuculanidae) and Pristigloma Dall, 1900 (Pristiglomidae) (Pelecypoda) in the Campos Basin of Brazil ZooKeys, 152: 1-20. doi
Images
|
