SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '54c93f9497aa12e57bf53e948a358801eb17bd1cbb6f750fa5862def9edf8aba' 
  AND token = '++QyyizUpJz3xGNRTK9JrVvtMKILmjQaDxgtQhTp66Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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