SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e429f36962fe673c9da7595dea61538750c11dd320295cbef12ecee3d6a10925' 
  AND token = 'rIZTrOKcxV3i0USLQjFGZwNXL4nDV7eYMgPKcwPCgQ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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