SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e86c69c583a7e7f9be34cb2d9410529fe38441f9df8d9b750aec3ae63500e62' 
  AND token = 'Zp3YfwuMnqO98NLDnDAMGsuFzYTm4rcGMzmCExfH6vo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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