SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2674ab7fd1c2a2fdc877965efa894b8eb4b51b522df100bd36615afb452f5db' 
  AND token = 'BqROKjj3K0/fluyZ6jt6hS+zNh/cNwidwsZDit7GX6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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