SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd20e55f08ea666ad60281f46c3d559ffca03b9a467543d6344ca494842db9469' 
  AND token = '1AsTal80fAK+c+yTcFTGqol5jknPRPZA0CDBgXGVop0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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