SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5cbfbb5210da67d75de0594ab74833b1dedbd619cfb088e7c554d8394827601a' 
  AND token = 'dLz0zH52rAKoS2KyXf0hHNSQVgUAveUjFrtKMyfHgyM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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