SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0d072ef74bb4f0637ed4f046969efb4cb83c64412cd3acc04ee7acb7a47b8fe' 
  AND token = 'kR5V//BXkH7aO5S2y7XSGljcVcNlozrXKCSVbHYly78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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