SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae657fd878512439b2b0b62eb614a9ea3a8811ccd8029b60fe96c6d8c000a50b' 
  AND token = 'srwouKBBqS+vnJ99kyAHjjKV65Xk+cTqfa3DqFTM22E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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