SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e023e11d2f251dab9111b15ece5b3b26fccf3799a544c84db0ad8c19f8fb3254' 
  AND token = 'xN1JaGtc02NCxBptmGFERV0x/OGCY8o+31RTT0cg0LQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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