SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a95e937dd5796c1b43a827fdd31a5e849b8581d8c3ef602e5e3b5345c966b0b' 
  AND token = 'BnmBmcA0QLZ0pZ/t+2wPsJO2jQCyCXshL/7j/vq/Hzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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