I don't really like "mandarin orange" as an English term. It sounds like "apple pear" or "plum peach".

These are the actual changes I was arguing for. (forgot to add them)

@@ -19,2 +19,4 @@
-<gloss>satsuma mandarin (Citrus unshiu)</gloss>
-<gloss>satsuma orange</gloss>
+<gloss>mandarin (esp. the satsuma mandarin (Citrus unshiu))</gloss>
+<gloss>mandarin orange</gloss>
+<gloss>tangerine</gloss>
+<gloss>clementine</gloss>
@@ -26 +28 @@
-<gloss>citrus (Citrinae spp.)</gloss>
+<gloss>citrus (Citrus spp.)</gloss>

sense 1:
native informer
daijs:ウンシュウミカン・キシュウミカンなど多くの品種がある
nikk: 古くから栽培されウンシュウミカン・キシュウミカンなど品種が多い。
eij: clementine クレメンタイン、クレメンティーン◆小さな甘いミカン。
eij: tangerine juice
タンジェリンジュース◆タンジェリンというミカンから作られたジュース。
kenkyu readers: tangerine 1 a 〘植〙 タンジェリン(の木)《米国・アフリカ南部に多く産するミカン》

sense 2: daijr says "柑橘類" (Citrinae) but all the examples listed (ウンシュウミカン・ナツミカン・ダイダイ・オレンジ・ザボン) are in the 
Citrus genus.
koj 1: ミカン科のうちの特にミカン亜科ミカン属の樹、またその果実の総称。 (ミカン属 = Citrus)
nikk: ミカン科ミカン属の植物の総称。
meikyo: ミカン科ミカン属に属する一群の柑橘類の総称。 (meikyo is unusual in stating it doesn't apply to everything in ミカン属)
shinmeikai on the other hand: "〔広義では、柑橘カンキツ類を指す〕〔ミカン科〕" (ミカン科 = Rutaceae)

Several sources do say that みかん refers to either Citrus unshiu or anything in the Citrus genus, but I think it's actually the case 
that it commonly refers to any relatively small thin-skinned orange, including 紀州みかん (有田みかん), tangerines, clementines (and 
occasionally to other somewhat similar fruits such as (thick-skinned) oranges), but basically never to for example lemons or daidai, 
despite these being listed as examples. What I think the kokugos are saying with their "Citrus spp." senses is just "member of ミカン
属", i.e. in a scientific context (though meikyo is the odd one out here). So I think there's a nuance we're missing when we follow 
the kokugo's example of saying "it's either Citrus unshiu or anything in the same genus/tribe".

I'm inclined to agree that on balance we're better off without the "orange" gloss in the second sense.

…
Every single one of the sources that Marcus Richert cited, in his rejection, were definitions stating the senses of 1) satsuma or 2) citrus fruit.
NOT citrus fruits, resembling the orange. (and you will not find any definition of the English "orange", that is any more broad than that …and that definition is very vague and oversimplified, BTW. It is, after all, from a dictionary, with the flaws and limitations inherent in dictionaries)
You cannot possibly claim that, e.g., a lime, lemon, or sudachi, at all resembles an orange.
A blood orange does, certainly …but a kabosu? A citron? (both of which count as mikan, under the second sense) Most certainly not.

@@ -27 +26,0 @@
-<gloss>orange</gloss>

since "satsuma" by itself is a thing. (I agree it doesn't have to lead)

@@ -20,0 +21 @@
+<gloss>satsuma</gloss>

All quiet.

GG5: a mandarin orange; a tangerine (orange).
中辞典: a mandarin (orange); a tangerine; 《英》 a satsuma (orange)
ルミナス: (日本のみかん) Japanese orange; (中国原産の小ぶりで木の枝も細い種類) mandarin (orange).　★一般的には tangerine, 英国などでは satsuma (orange) とも呼ぶ. 
https://en.wikipedia.org/wiki/Mandarin_orange
https://en.wikipedia.org/wiki/Citrus_unshiu

I've always regarded 蜜柑 as meaning "mandarin", and the JEs agree with that. To me "satsuma" is the Brit word for mandarin (it has a bit of history, relating to Japanese exports to the UK), but I agree it was called that in the US well before then.
Since 蜜柑 is Citrus unshiu, I think it's appropriate to have satsuma in the gloss (distinguishing it from Citrus reticulata), but I think "satsuma mandarin" is probably the best thing to lead with, as per Rene's edit last year.

@@ -19,2 +19 @@
-<gloss>satsuma (Citrus unshiu)</gloss>
-<gloss>satsuma mandarin</gloss>
+<gloss>satsuma mandarin (Citrus unshiu)</gloss>

It seems "satsuma" is the most common term, maybe both in Europe and the US
(found 2 pages at site:nytimes.com where they were referred to just as "satsuma" for instance)

Does "orange" make sense in sense 2? I think Japanese people often translate "mikan" into "orange" and also call things 
I'd call "oranges" "mikan".
See the chujiten entry for instance:
みかん３ 蜜柑
【植物, 植物学】 a mandarin (orange)

a tangerine

《主に英国で用いられる》 a satsuma (orange)

みかん 1 房

a segment of a tangerine.

蜜柑色

orange

tangerine

蜜柑畑

a tangerine orchard [plantation]

an orange grove.

(and "orange" is a pretty ambiguous word that can be used for a lot of citrus fruits, see 
https://www.dictionary.com/browse/orange )

@@ -19 +19,3 @@
-<gloss>satsuma mandarin (Citrus unshiu)</gloss>
+<gloss>satsuma (Citrus unshiu)</gloss>
+<gloss>satsuma mandarin</gloss>
+<gloss>satsuma orange</gloss>
@@ -24,0 +27 @@
+<gloss>orange</gloss>

https://citrusvariety.ucr.edu/citrus/citrus.html

restoring correct gloss. 

"citrus (genus citrus)" does not even get the binomial capitalization correct, which is pretty much the most rudimentary thing someone learns about taxonomy.  "citrus (genus)" incorrectly suggests that this refers to the genus; it doesn't.  it refers to members of the genus.

@@ -24 +24 @@
-<gloss>citrus (genus)</gloss>
+<gloss>citrus (Citrinae spp.)</gloss>

@@ -24 +24 @@
-<gloss>citrus (genus citrus)</gloss>
+<gloss>citrus (genus)</gloss>

I don't have a problem with sp. or spp. (https://en.wikipedia.org/wiki/Species#Abbreviations)
We have guidelines on these sorts of entries: http://www.edrdg.org/wiki/index.php/Editorial_policy#Names_of_biological_species

@@ -24 +24 @@
-<gloss>Citrus (genus citrus)</gloss>
+<gloss>citrus (genus citrus)</gloss>

koj, daijirin, daijisen
https://ja.wikipedia.org/wiki/柑橘類
and from that:
https://en.wikipedia.org/wiki/Kumquat
https://en.wikipedia.org/wiki/Trifoliate_orange
https://en.wikipedia.org/wiki/Clymenia_(plant)#Taxonomy
https://en.wikipedia.org/wiki/Citrus_glauca#Taxonomy

Taking a closer look at some dictionaries, and Japanese Wikipedia, it would seem that mikan is, indeed, also used for citrus fruits. Interesting.

Citrinae covers far more than citrus, however.
Mikan does appear to cover more than just citrus fruits, but still far less than all of citrinae ...and when I looked up the other genera that are considered as part of what mikan covers, I discovered that they are now considered as part of citrus (though there is some debate)
As such, just simply defining it as citrus, should be fine.

Also, "ssp" should either be included among the explained keyword abbreviations, or strictly avoided. It's hardly common knowledge.
Of course, neither are many of the other keywords, many of which even seem to be particular to JMdict/Edict. This is not a criticism. These things are needed, in dictionaries.
So as I said:
If explained, it's fine. If not, it'd mostly just confuse.

@@ -24 +24 @@
-<gloss>citrus (Citrinae spp.)</gloss>
+<gloss>Citrus (genus citrus)</gloss>

koj, meikyo, shinmeikai

in fact, i think the original sense was not broad enough.  perhaps more clearly handled as two senses

@@ -19 +19,6 @@
-<gloss>mandarin orange (esp. the satsuma mandarin, Citrus unshiu)</gloss>
+<gloss>satsuma mandarin (Citrus unshiu)</gloss>
+</sense>
+<sense>
+<pos>&n;</pos>
+<misc>&uk;</misc>
+<gloss>citrus (Citrinae spp.)</gloss>