SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ee292ce360d2bfd8950e04ab88536b38597aea6f4d5783db6db89fc97313fd03' 
  AND token = 'XdVxra1v3c/r4+zZ52FIPC8sFqSVKFsjxgfvBimSshI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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