SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'be466b6b37749537fe37e2ab5d84609c342262c909928dc8db9c3ceaba7ade10' 
  AND token = 'dkMMomVQxA+SkYWtPBrzeIAF/uwGfMHTmvtyo4p2d/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}