SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e613fbdaa6826beb1d37162145364ccec967c238ad1bdd345b8b1b3c42b14fb' 
  AND token = 'X4pzDLuNQs2L9aJpUanIATdVpwG9Zn3e7UjvPkBmS9k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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