SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f11d6fa54126397c053a87a2085e9d0bef6f22fca1a1672bc8578e21ffd78dc' 
  AND token = 'L3vP8DEf3aHWpZGYOK6sPDkDr/c1mNXu+9KmtiUgwU8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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