SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4577de6f6b2962727fc5f9d85e89c8927e8a5edd86f7e3ca53ec43d223f3f045' 
  AND token = 'EWoQauS5aZhGGqpRCVXu4Y9/vOlIQIXB1dXnis7xAXY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}