SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bf2c816e23340af8f00af9cc870fedece0e5b1867ab99be4e75aca3926d1049d' 
  AND token = '0rOdcCnE+kvjqtXu40rFqX1eb+mQtLGiDWy6X6md8l8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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