Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fd50451858d7fb0f6891d25d6c83044562aeea26e9636e2c3b000b796d40843' 
  AND token = 'UpwidlK0iiR45mMbnrayzlzjHDTyvRZbnKVbv5kChD0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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