SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f1ae3ded8606ef95df23e3d6ac57b5951b9db974731013453456f3c008e0bf7' 
  AND token = 'TTqz1I2pbHiIJbVpW5WNciSFEXMcoibRI9y+5cGtdSw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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