SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33d1cad7183958246cd3019ac874dccb240f4a3411743abea7bddb1c0f3e3486' 
  AND token = 'oSnxyCefoRcLLhGQmkjY9QpIdIA1HIAqtOZ9o1Nh7Ws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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