SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa6e5bc0227e9bc217f171dcff1acec1d0ea853dcf247f87b776a051402dae00' 
  AND token = 'EI+tf1PSrp2Ls0UfqO2JXGVE7LMymH/MAFa8q3lfx+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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