SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae0980c7bc52d9fd739b25d49a4a24be9243052ae61ce7da10e435ab376b403a' 
  AND token = 'jGxUM+uzFkGYlLsoaUKmI35da6eqpn+vld06uxBpb3c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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