SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c83d5a8da511763df9b648b45de0437c3551ea0011ba027659e66004f5410933' 
  AND token = 'kGiNksERENCeeZ5ZK4/71wBBHge53sL+CrLsiGWVVho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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