SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdd59b532c6704c3698d05964283a8d8d2a74d4b235105fde32202f6b104c612' 
  AND token = 'hz7J+sm39bjDImREWCjkOc/w0T7/Icoo5xggGiF/7Yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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