SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb268c0bdd35622fe7e169642ddb0195222952b3cf874289aff0ba7165f2ef59' 
  AND token = 'zrh9qG739HwvqYVLfwybLRh+XJqZHw1HxzaDuJnku4A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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