SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0090560b209176abd7cb7da0bdb985accf6a93545b4dab767be4bc1a2dbdcaf' 
  AND token = 'fi8JhcOI5WV52yeI0HYD/ZmynLpcNMbxVWx6oZb4bK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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