SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ecb432fda76e91a1c9f23c4e0573b42e3224d737a13e1bdacd256968350b084' 
  AND token = 'YcUTjj6vX6IsRNUkPhqjK/9+VQJYzOegpV7tYyp+oc8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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