SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f8fe09f073de11820ec77afcaaab8da556e3fe8ff016d38b403f54395dae299' 
  AND token = 'v0ZpJs1K2lx310jWanuPYonMTNRo1cTSy8ZxooD02wo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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