SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '895a88a13430c132eabb0f1cc85de24adfb33888f6f4d7f9d0e4a859e152366e' 
  AND token = 'KnuBFOjty0/fqE3ffFd0alUBj+7Fv4cSVqQrsoAVaJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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