SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd29b0e7502cabb8adbb0d5f591536f8c8eb4197bce032aa7ef3d0e90d31e849' 
  AND token = 'BC5vcyQ5o7H7naWUb2NsTfYuFL31DnUxu0yj8XhpLg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}