SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7c8600b7388ddb3d730222710e68a6906701bfdc4b670e8748ed7b35d7da8aa0' 
  AND token = 'BvVU3quWAzm/Ja47pTTn6jHoRs8xdlLlTLpJhlZBgK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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