SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11d7ea9d5ca254a7a570f011a22a1fc49e60a35e82c0e81238053b2182ebb713' 
  AND token = 'KE73thlQJFsArfhdVbwn1GsxhrgJcaLj2IDc3S0pwuA=' 
  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"
    }
  }
}