SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b7b91bee8d034dd710c54031c717e36c1ecca8dffd519bf96cc508f01990ed41' 
  AND token = 'dPv5qs7fR77R047PYkkRWbJzKnDp8xSDPLbVerZqmmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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