SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e494229e6abadb2c91399955d6a1f1fe412a06e9241d285fe8d4b56df3aafc66' 
  AND token = 'E570aC1v4I1x9m+6Fp3H4O8QPuWm1GvxqqYwocBSZyA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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