SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '073012fdf9b95b2221d853f2831fa5349b66ee66e412821d1940b5d648298196' 
  AND token = 'yjjBLv1gDlA+Js0g4URsrGcEnOUVBuX5F5ae8HVYWYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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