SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'df207e0b9acd506142c5d2b2dc98eddc725bdc96ade69480581822fbd8b8c533' 
  AND token = 'FPojUDy4eH90XJKWydHuj8WuKXQZc9Lo++6huE/Xy3Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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