SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e64c15b2778044b57dd955ac8f246f46dca9a04f1cc799235342f679bb3b71ea' 
  AND token = 'qaglL1kNurt5zw0LCltP4C4WqEM0iu8bisq6QrhXspQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}