SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48a20a06ba4370f5605d9eff8123193b569a627363052b27f14cde68186e51e5' 
  AND token = 'hPo9m9sPy31Eb+nxUaKpGwBjlgn1oUfCbFGvvIPDUv0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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