SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bd2c4274814f9e5bd32298823c1ab32e07989fcd28f4f07fbc6f5d4e08c844bc' 
  AND token = 'dmtSY/H1mw+T8eGvFohA1uZdvh3XhAR6ZUOrVT+S9Ak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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