SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11a258955d90515aee29c2e9b95ab703c6a5687281423f8654dfd8560901167d' 
  AND token = 'vlrSzcrFVzf6BsK4M+Igvg9FmVx0zTyJ1ZJ5Ha2cYGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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