SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '26a46293300c81705b757feb4d2fd73f910ff018285d585ff1bb93a15fe3f873' 
  AND token = 'iWvrNBYwN+9Al0FHQ0AQ5qQH/KzS9gKtRlS8icCoNzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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