SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '98b98d31d622bcce4456a5383837ab40b49cdd9db6e15358acca546d6a1b9851' 
  AND token = 'GtZEekI3EoPgEildq0CRZSF+4XEX60zRaDcYoNXDos0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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