SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9eaa59314974e84162c71266b6ec2e5d0ace2e4bcedc76ad26b474e94dc1f67e' 
  AND token = 'taHqE2t7ekh/GF6AgBjCCbIXTp0EVRE4biCqS+FtRig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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