SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e8981d98367e9fdc8b7a5edff2d76b82c11a55aa09474b9cbe1d63e23753fe6' 
  AND token = 'ieJVQjCE4UJKu9StSZna75Ecbm1VbprvZe/KwY32+3g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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