SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78b8f1a78c18fd481b58c627a756537adecfaad5d37a68f895cdc421f637c6c5' 
  AND token = '9G5C1NhdC33yCz0uGVkpQL+ATcBWnuranqOTaOt6I+c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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