SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a45d7c3d7189cb68b58dbf770126ab8245aa18506812bb0a5244a5839bcb78a' 
  AND token = 'YIl0w0t/OTdjJ/2q0g+GMj9XvuGQlxYcUwNc7t0HhAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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