SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af4393c59e093c2699cbc21499533a72d17528ad5a222b410a9d887e6f924b3e' 
  AND token = 'tsUvEiSpgtw6efFWMe7HqLovnzsTq+M4paDz0KjSBog=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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