SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7bac702de5c975219cc39b798d648fc4b5b27f6d39b5000431169aa0ebd2a615' 
  AND token = 'ZXx2HR0NNgZTpgDeYk50iz+LJ3ZsPCutLtsLW/QnQHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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