SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '49ad4a06725f0f3515669a10d526afa9f6bac5538ed6c65345d910ad38a2c80b' 
  AND token = 'E/SUdXex2juFzLn+dKF7Z3t1GmoVNGLGo2ARZllwqdc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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