SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df9bf58cdb708194efd33c9521eaa3b4b63c36f13c74f572587f5e592ffcc20e' 
  AND token = 'G2LUgwErliAM23IHTAsT3sOlB9MlUiv95KqSHSoLkKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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