SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed817352646c39ba9308e34504938f95f97b65d6484bcfd177841e97f3c5d67d' 
  AND token = 'Hql1BSPpFjHc1vGavtCTbT97TKPuy7qvXOzAMWd6mGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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