SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '88355c65ca8a79ad70ae6bf059e269ecd6f13ad7e02b017259642f70a5493d06' 
  AND token = 'Ovy9MlDxrwwggjTg2W38JNC9yCWhFwNbYtcNo+GvwEw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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