SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cbb5cbac59b85a726bc37ab4b24bd4258983a88c75e8253778193b9a2af2226f' 
  AND token = '/YRZEVLqJJooQb51Zg+ZqsF27jGO0jx4RpBSYvQpVrk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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