SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e15e627a7ab8ffd9c87248010f09a217ca6446f15ff8bba72c36328f73a7c4f0' 
  AND token = '571bjs7OH3fTKTrD9DnUgtQf2CobMfeJfvQs5UYwrZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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