SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '582ebe2882a8e55eecc0ad642ca19bfd297a9e039fc1219e7d300a825743d3d6' 
  AND token = 'YRuSEZwNvRAQjiYiropkNLgz/r628vT7vh4bGbTZO8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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