SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34bc0befde77ed9dac60dad42656134b1608e54ad1864c0fcf9cf20111e9c118' 
  AND token = 'ihSeLChzcDDoy3e1PjgEW7TSiIqwCHeiSU9Zb37kYQ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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