SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecfdb6e53d0e6999a41b88217a219c151dd7cee17e5cae86b0fa2bd92da2aa98' 
  AND token = 'DvIBqfG7jmwHNK8w/Iox8R+Ss8JHGNhms6o+QEwCdXY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}