SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd765100904440258871eb38bf7c550ec78b8f249078bf950d16708ebbed69f9d' 
  AND token = 'KXtcfkmZKOOgh+EZk6yJaK4+bRMUt/4lNxS5AO5ASiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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