SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ef945b403648466466f6f7e8dbfa985797b04ddd2aa92fd67c53dfa5d85c7260' 
  AND token = 'uua7qKLISBszDMzfrJIwvhhguy3h6CC0zBIzs2MZp1M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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