SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a1f060161a82a4f59bc00a76d037a3319fcf475dfdcaa16ad00622460ea4d73' 
  AND token = 'kFTrmcv+/qaIXABnriBua4xPYA0mYpIBvRQTKAb0qoY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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