SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f420a913e7c42b651cc05b77d221ef3aba29bfc6a50228ec5c6f620bd9f0b89e' 
  AND token = '/z6gw+NLiSsW30HKCIlrELOywHqYXF9OMQEt1CGWK5M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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