SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '606aac04d9e946d6358ef28a3e4eb81db49f4c288b1f856a77a376000c3ad5b5' 
  AND token = 'zOGisA7x96P9S+7cw3B+PbCS/zvJqryHgBEhNL33kDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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