SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27340d038f6f4d95cf03719fa9052c83c5b5c935833a5457fb9e17867fe19417' 
  AND token = 'k+tijyBUIRnK2PgHrBjs1v0wUKRFek1GBeTziZZxdoA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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