SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aad6667ef244e3a4eb4acf3fbc736ee10903c56027c66dc51913837c24510fb4' 
  AND token = '4EUG37Kh006fAUZ6+1HyvvJat81ruenb/6zntrg4iPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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