SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb48ca60d874829c74a9cdb21dff6dfa04529c2460ae25bf983bfd8ea34917b6' 
  AND token = 'lQD4qyBrZVzhM9VmzdReua7AHgFLIaXP7tRW6xMVFpc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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