SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '221e451d25932df0aa50e9307006d8244123d1ea62673a8fb4fccec841010d19' 
  AND token = 'bj7Mcn0Qe0h2AnztIKAt8dyEePvQJz8B1DVFcek9pm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}