SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40f44977a14376a8919a984047bf6a1f059503b265d60765663f1458ba6b4d1f' 
  AND token = 'WZG4iLPEs9R7F4sM0OO1bSFm7GFgoNmcNfyF6djO8fY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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