SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca0ba9f8426ef84478aa0f86a35f6807e11d49d99313540bf58b9bc73c83ed68' 
  AND token = 'ZnvkSuuM/vByNBQab9Xt5ofpmvnc6Vg4co7I7MWfeLY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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