SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9801e018e5cc1843d21042e69fa0a42f7d8fcc553e5d162cacfd815392fae5bf' 
  AND token = 'nXBkXhrgCrCILO66IpknSWgWm4NiqNAiEHgWBTKikB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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