SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b6f5ef5c0e7a7b625ab431acc9977b312e35dcde7632424ebb49e5d1b19d163a' 
  AND token = 'tvOICQSE9x/NWCpCUC2YG0fg0zpitRj+5rLqM9TAKMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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