SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa785e109708e87e3346f9acb8ad4dcb76d6f6abf4da1f1bdd4e74e92ca29c8e' 
  AND token = 'hCzrxLQ2AhjI/U0wwccJyMfPFdLvgi2DgOJFRIaDsS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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