SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0dd8f1285bfa9c26bc5c8eacc1ec63b6b4627a6b19695074db7348b57c2c2d2' 
  AND token = 'F6L2HS10t1OPmnPAjPxqkFxUdEEejnKtaWiBYupJ16o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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