SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '53abae73386d239398fa653d0a6e67e134b31d45f10108ec0259519a56adaab0' 
  AND token = 'C0Nq+VK+rs9Jza+ipBJQks9fOIQHBX+TmchZHYthl18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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