SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff27fcfa54cf667a5f85d55d594febce0b8c0fa7229521a24f6a462315f05020' 
  AND token = 'hRgR1mUeICfqpxBUV8ev+7Cof9KZ1pIHsl6NN/Dv6Ww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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