SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a98eac9ed292b4e90e76efd3162e841767c6227bd301f3b081ad57de2c65f089' 
  AND token = 'v8UaXKSXqKFvyt+p0OhtIBKytiYCjOiiG0cDJ4g7/OE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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