SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6be397a9a73ffe1a8b4690121ddb98e3b9b32569259129423d1e5c73d2225930' 
  AND token = 'o087L8Vz9g7TVP0qmygQu8cdad/o4Vtgrsd8JX8j5mU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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