SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b4d28f953ce8895c05ad54974d0612e5ce71c35b88f1246c2e67520629a74f9' 
  AND token = 'mw/0fIkXYhP0HjCIBfZpPOE/bfMic/2JNGdB2HiVe9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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