SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f041ca85b0ce0fc4994751161f8d3c1caa657fa7f9f8446942a08b3c9395de61' 
  AND token = '8jjTejjyZocBlriru27o/Mygv7i4ILlS9umqbw2z9ps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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