SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28187cf371c4c2697ecf0817e35d0ab0465a45060e347c7acb438d1f252785c5' 
  AND token = 'SqiVPjTbYffgMEFDsqvI54Mus8qvLyPlW3fzTHco30o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}