SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '442ec632c8609240f58dc87ced4d855241da574809adec15d9919e5e057a6a1a' 
  AND token = 'lOPNHChzAqB+0VWg2WoB0zkNwI9+L/Jx0ZQqoL6/2NQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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