SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8393b8faf72b0d917ec13dab702116645c4fd100a9fc59706628875ac89835d7' 
  AND token = 'IeBTIcNoYuykZbHoUIdCATvNi1h2PJquO+fxGkzUupc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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