SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '57696a0e6d7bc24411bb36e7f90c07a2228bdac7211711acc034279809fd90f5' 
  AND token = 'X3j5GL4alqB1YXQOioJWSVuJeuzNBvgLjiul3oLbu00=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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