SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6e38a12f75f3532740b678d971bef4591cf1167f13f30d6104f9e0d2f30f6a69' 
  AND token = 'Jyc+VvYNp98XdP4lTCh4IdFR2oNmtX5C9idQyzKBueU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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