SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfd5a1da52611ddc09206227b5c13899e3ef5ebba6b3a85975a6c3f3b9ea2418' 
  AND token = '2+8vJdgzO5B/G6phlGQlePFrXzgeLK0bNABbuGa1J+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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