SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dde71e727e56b10249ec4f666096cbee69ebb7228332d2e0657061cb392f669' 
  AND token = 'KKBJAGFVeZX3MkiPGZaZabFafbhc4scg/Ki2dPI2FAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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