SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '062423cb9db7499ee8e1c2288f172adfb9d48507c508bea946dfff5feda5349e' 
  AND token = 'K4v0mLVe2byPMpOSgx5a+13tE7cQRkFbOVlvPQm7lN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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