SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1de6f6d2fa36dc11bc1fd8ea889c7d983ea153c239408a6117e674462ef28cb7' 
  AND token = 'jCi7z7b3euFZ0vcYKm4SQ15zcj/MRR1Xw/sgPH+5F5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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