SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6455e539f3ca0e432af195ae4c05ce7aadfcddffd42ffd19e151015ae569ce8e' 
  AND token = 'jL2TH+P2dakAebRXQTx/49PuQmlICW2RPi6MGFIMyoA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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