SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2f7e8e53e85c3feb7398ab1d5d70a7847fd21d339becf47359cd63815987385d' 
  AND token = '8pOHxjE4KTjhPxe8pklDlRfGScBjkG56BI2pTtQF58g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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