SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91118b1ae51ec5ed21d85abce106cc7b4863f05da74768684d950ab52d71f97f' 
  AND token = 'DpDMXxCzOJfHt3YaEfEtgrLlOUa5R6Hp0OuvsjXn02Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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