SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '431a8b8f66327e62589b5213c4e21d4f8b456307df0f3c20d09f5309faa80726' 
  AND token = 'CcwkNq9BbWtlhfPBwzlNuB1HFYX/jPk158IoQ2gSvBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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