SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1531187c84426f5d362caf52b72f60e344ded2b66b380d33efff6df27674a63' 
  AND token = 'q1mXmpPg1adyPGdMjN3WoJFAS6uvnUMzpGHe0wFTb2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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