SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95986fb50d2d1c3fde64a0d0de7ed2c608d976ff44536df474f91abaa716a3b1' 
  AND token = 'BMxijfkhpSwUAfm8ioGYVnOpYhZpPYJ1PagBCaCu6Ro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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