SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ccc1f94fa2033fbe49fa6c64cd465d243f1e86b3e615c808b96a2d1ee05d135' 
  AND token = 'Xnj2Hzgw0IGEd+g3wiAkryeOWqRyacFtFEV062bHrz0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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