SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c0b14126f668576a961670579a3d35a32088f56c3f9a6c3ddf410df829164dc' 
  AND token = 'tPJHnKmvJYAl4ltznXvaKCPNycLNUscw0bHTPI0TNcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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