SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bee754d0ddad1d6441c14fc773b4e9dc2f68236fa9d0ab637d257e061b22a7fe' 
  AND token = 'cfhF3BZoQw8jNW98sZVL+Zvwb6yydc9ppxvFnKhA110=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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