SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a8e11e7ba0758dd258141cb7ef7cb22ea604f802e78a5bcca548ac768a945d3' 
  AND token = 'O0zT7OygYLFDOfdr7NOU8h98zZvwJLpygEPK3XuK5jg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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