SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6249c54fa970964e3d8651eaa8238f4b2c1945a4fa03f1f434f2b86eea297196' 
  AND token = 'EUaf8/R0ahkObITJ+ZbSROq5AfLc9MUQX+rs87iU0XU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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