SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb69d3de33b76e60e9dc732dca1356bf84deb69272802907d4987caabf0e2009' 
  AND token = 'JqteJNYZQrQgZGShP9fXVivKGdkEboLHj1p+tW8b88c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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