SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80e88c99a24464503aeeb82a09105a357362fca7d9dff5436e7b6e8d8ff9dbb6' 
  AND token = 'XYCJ0pbFADN9Qb3JsDrqZlqHT5Cyn+zyfvnlutwWq3c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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