SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab042813c2d0c850e185a4d7b47800d391422d25540173d68092e0ff3922e193' 
  AND token = 'DRAPW4zG0qq1gv5mUEzkOtKCou3qkjD9FSXqIBpepOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}