SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a30a656923ad905cb28901fc7575f6f42e687143425009e531199974683744cb' 
  AND token = 'nRR9KBaWTmote2/vrZUOZ5Ej3sJIToDQ35zLGHrruT0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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