SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9666efa54e198af99acf73c497c3beafe59aa1450f0f0c9d2ea6d27aeba4fd5e' 
  AND token = '0S6yldDeFXgd8oGLvkYuogSCIkYhDiDf7FjECOS3KaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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