SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e5f3413c834310f37283d773fc21a3b97e39ea7d5571fd52905b5c9ab9189733' 
  AND token = 'MhKdraRrGO49iP3g2D2tZOdAPYnqVUEy+GK8ZlzPsts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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