SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dcd13b4d4fce0480ba293997032d9c5c3e499584dbd0137fd19bbfacb0056d7' 
  AND token = 'Js1htFqG+jz93LKulgFxG/8UhlhVu+dc/lrAm0IgBUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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