SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd5680f7f0ed07d8014872091e8239d79d113ab7f6bbaaadffed7806e0dc23c5' 
  AND token = 'Oi1THSo4Pj14epxxlG4lCYwkodlISSMQAJvN67DetyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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