SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '954a24763b464485ddee802dcbe19cf785eaad5e1d288b6745839a99427ef5da' 
  AND token = 'qXOA+Txc1V6ta1GZ5c7T8HCFyojD18sXmLuctaQ5aYg=' 
  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"
    }
  }
}