SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c3da363897db73f8b0d56df7f55f64405a3543bc40d5dbc44ad622b57325e2f' 
  AND token = 'uic+RLXwBeeIg+gYopT63CVEnJtnrc1tPIQiSVbW03o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}