SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d7edf9455859e065d6c998a32c871e7b7e4ebb6c69cfa85dd91698494820c48' 
  AND token = 'oh3CJuTprSKS4aOWNQdxPuiuJll3PY93Wdj85iQoyXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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