SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f62bc8d9db851f3afbef9f26b63046aaeab4c1aeff369c7e68ffc313c310aece' 
  AND token = 'JRsQm2lK3Za21AYfNGNmdLPc6EfsszwjwFvGqbEefYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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