SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce4b98d15f50e64dc66274bccff3ea9e41f31f77e4a73e38d4285fd6de5b3319' 
  AND token = '9EVKnEHWRqvJmWsmbmSi28ifZcKh05Gz/DyCMhKzzXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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