No 14352, Tuesday 10 Dec 2024, Arden

 Solution to 19A has been deliberately left unsolved and is to be answered only by a non-regular / novice commenter, with proper annotation. Those who have answered earlier in the week, please give others a chance.
Open for anyone to answer, if not solved by 1 PM.

ACROSS

9 American city in the past (7) CHICAGO {CHIC}{AGO}

10 Ruffian holds aliens, releases (4,3) LETS OUT {L{ETS}OUT}

11 Root of a plant embryo said to be progressive (7) RADICLE {~RADICAL}

12 Apathy for Maoist's involvement in blast (7) BOREDOM {BO{RED}OM}

13 Napoleon's skeleton - keeping away from each other (9) BONAPARTE {BON{APART}E}

15 Left in a primitive accommodation to give birth (5) CALVE {CA{L}VE}

16 Envoy to a lesser degree (7) DIPLOMA {DIPLOMAt}

19 Hector and you close to the capital (7) Y?O?N?E YAOUNDE {AND YOU}*{thE} See Comments

20 Fight to catch river fish (5) SPRAT {SP{R}AT}

21 Elation when you're on it (5,4) CLOUD NINE {CD}

25 Herb is in a shortage (7) ANISEED {A}{N{IS}EED}

26 Play a role - is it a part of your face? (7) EARLOBE {A ROLE}*{BE}

28 Bengali became European (7) BELGIAN*

29 Arden is perhaps a swimmer (7) SARDINE*

DOWN

1 Extremely symbolic horse beetle (6) SCARAB {SymboliC}{ARAB}

2 Called POTUS to protect democrats (6) BIDDEN {BID{D}EN}

3 Clatter raising some powdery stuff (4) TALC {T<}

4 Question about you - finally he is affected (6) POSEUR {POSE{yoU}R}

5 Fat novice stops by (8) BLUBBERY {B{LUBBER}Y}

6 Impending danger gets slum doctor worried (5,5) STORM CLOUD*

7 "Died in building lobby" - one wrote a song (3,5) BOB DYLAN {D in LOBBY*+AN}

8 Frank readies regular flight (8) STAMPEDE {STAMP}{rEaDiEs}

14 Experts' treatise on the addition of a sound or syllable at the beginning of a word (10) PROSTHESIS {PROS}{THESIS}

16 Danube winding around quietly in the capital (8) DUSHANBE {DANUBE* around SH} 

17 It's tiny parking, clear it somehow (8) PARTICLE {P}{CLEAR IT}*

18 Stress involving mind - it's regular tragedy (8) ACCIDENT {mInD inside ACCENT}

22 Songs on South American port (6) ODESSA {ODES}{S}{A}

23 Famous and active - essentially nice at the top and bottom (6) ICONIC {nICe}{ON}{nICe}

24 Cricket team will stay in the hotel eventually (6) ELEVEN {T}

27 Capital is half-half, that's uncommon (4) RARE {haRARE}

REFERENCE LIST

In=Chic, Aliens= ETs, Maoist=Red, Left=L, River=R, Is=Be, Democrats=D, Died=D, Expert=Pro, Quietly=Sh, Parking=P, South=S, American=A.