SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fb4b65e41cf368f8c251a7594aa18c7c6c0b56032eed98ea06ab5d162c6ba253' 
  AND token = 'xNn3fHlPLc435T3hlqvT+tuKkJyiUbFjREemP/bgS78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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