SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca9eaf81bcbf362aa6c5d9b95d68bb03691a6ee3f3198c089914333a4a3136ef' 
  AND token = '2sHllQwCJGVuzkuElNnowHDWAOYMuv3wBwebDgb8MJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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