SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11ff9862afd54c99d55979ac3316deb38f11397ebbeccfc3d5cb9335dfda9ba3' 
  AND token = '6ne82i0meM0oxI3u0OPGMz6umrK0TjHdxDwMrm7Fxqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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