SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e09c5538caac8f337f040d546545646bc82a0cee6e7a4b497f2c83190e8feda3' 
  AND token = 'CqLb5F00zZ3F7sKBblJDFPAupWoLF1ZY+pDsUXTxV0s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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