SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d6bcae6788e01e798a4d6191ff5e56431f0042a43d51f20eee1a4f9974328ff' 
  AND token = 'puYMJALujvwehfqyKZNdghLTZUMuMd7Uv7kvT83VzSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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