SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd64fbc491d0b13ef4fe75a5ca10a4ee872683847c32b876fcfc0af02f347a5d1' 
  AND token = 'zNkFGThIjBKp74oWZWPXWzYXwrR9EiiWm5KYFwuZxig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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