Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fcbed9fad010db37520c7bcb7267031d89e36abdb6baa7c9ca960418547a141' 
  AND token = '/SaGUK+UAQ3PJT4XL9tMG8teNZwMZw6LKRAQCQI4JF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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