SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c674dfe32359b2587f490d4700cba46df3ece4cc2f6c0857ee49de4520a19d3' 
  AND token = 'Zuzflj5lDMFK57suchv99kC5rQyWhTF6LtCFVlQR6Co=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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