SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9db65a6460a987ee6ba1191184252c58dfe5c964be310f969d6717fa2636163e' 
  AND token = 'usjzzrAq1CkFcQehBNb/aypDf1siHaoPUeiVZ6jVZFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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