SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc057668f22b081fd7aa458078afac854f5a73c1c941e398cb7ceb5040b0d2a7' 
  AND token = 'bvIWn/KRaLiGsuPxpZbe946Pn+BekDXiy9+biG2lljE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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