SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b025611f2d6e975263a8828a4b8471a77a3ba011d998579e89e1256f0458e37' 
  AND token = 'govAdNX+wQmePmJV1MavBxM1ZT/aHxgv2nez6uurKhA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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