SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd1e2f03b2ba0e2466b9db4f7137733c3c2191ffabffa6a882cb65fba6ffa155' 
  AND token = 'suXQhxfXSMBKy4GvQ08H+nYzzZukJOfl2VLCbLWB4oY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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