SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5f3a3df86004a16ea2339a3af202f71ce783a4c8c75be1e986492ff419c7a4a' 
  AND token = 'hKiTgvYSFluX4LAoKKDtZpRUvx2YBiTE6840GmYgjCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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