SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14e679aeb96a6d6560b424b97d65bd424d31fcf9e673ec14fbcd8b0feba3f932' 
  AND token = 'iDYuqZDiUe79RjIEV7KLDf/GLziECkZojddHxRuxISw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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