SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f47fdd0084149640c715f2856459ed8aefa91c4bd4a1d25b7818eefff5af10e5' 
  AND token = 'Kf8OEsHZWO8EYwpbMgwneJj/kVi0a/DvIr+aes5BRtQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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